Course Handbook

SAAD National Course in Conscious Sedation for Dentistry

COURSE HANDBOOK

Society for the Advancement of Anaesthesia in Dentistry

Introduction

The handbook which follows has been produced to complement our National Courses, and so reflect the syllabi set out in current national guidance. We have designed our courses to help provide both dental and medical participants who are ‘new starters’with the necessary knowledge, skills and attitudes ahead of supervised clinical practice with an approved supervisor. This is a mandatory requirement prior to independent clinical practice.

The focus of our courses is to ensure that all members of the clinical team are able to deliver safe and effective conscious sedation for their patients who require it, such as those with high levels of anxiety, during potentially unpleasant and distressing surgical procedures or in other situations that might require conscious sedation as an adjunct.

The provision of effective pain and anxiety control as part of an agreed and consented treatment plan is a great attribute. In the UK, both the General Dental Council and the Department of Health consider conscious sedation to be an integral and fundamental aspect of the modern practice of dentistry.

For those who are already employing sedation in their practice, we hope our courses provide a useful update and stimulus to further advancement.

I do hope you will enjoy the course and find this handbook useful.

Stephen Jones President of SAAD

Editors Leah Adams and Zahra Shehabi

Acknowledgments The editors would like to thank the SAAD Faculty for their contributions to this handbook.

Table of Contents

1. Anatomy and physiology 4 2. Principles of pharmacology 10 3. Patient assessment and treatment planning 20 4. Local analgesia: tips and techniques 24 5. Intravenous sedation with midazolam 29 6. Inhalational sedation (Relative Analgesia) 35 7. Monitoring 41 8. Management of sedation related complications 47 9. Paediatric sedation techniques 50 10. Alternative sedation techniques 56 11. Sedation for medically compromised patients 61 12. Psychological approaches 67 13. Legal and ethical issues 74 14. Standards of good practice 80

1 Anatomy and Physiology

Introduction It is important for the sedationist, dental nurses, therapists and hygienists to understand the principles of cardiovascular and respiratory anatomy and physiology in order to appreciate the changes made to these systems by the administration of sedative drugs.

CARDIOVASCULAR ANATOMY AND PHYSIOLOGY

The circulatory system comprises the: • heart • arteries • arterioles • capillaries • veins

Its main function is to deliver oxygen and other cellular nutrition to the tissues while removing the waste products: carbon dioxide and water. The heart acts as two separate pumps working in parallel. The right heart pumps venous blood to the lungs, where oxygen is taken up and carbon dioxide given up (pulmonary circulation). The left heart pumps blood to the tissues/organs where it gives up oxygen and takes up carbon dioxide (systemic circulation).

Coronary circulation The myocardium receives its arterial blood supply via the left and right coronary arteries and their branches. The sinoatrial node (SAN) and atrioventricular node (AVN) are mainly supplied by the right coronary artery (90%), with the remainder supplied by the left circumflex artery. Venous drainage is via the coronary veins which drain into the right atrium.

Nerve supply to the heart The heart has an autonomic nerve supply. The sympathetic supply is via cardiac branches of the sympathetic trunk while the parasympathetic supply is via cardiac branches of the vagus nerve. Under resting conditions, the heart is under vagal tone (this reduces the heart rate). Stimulation of the sympathetic system is part of the normal response to fear, producing increased heart rate and force of myocardial contraction.

Average adult resting heart rate = 70-80 beats per minute Average heart rate for a small child = 130 beats per minute

Tachycardia (defined as a heart rate of > 100/min) and bradycardia (defined as a heart rate of < 60/min) can occur in the absence of pathology e.g. the tachycardia associated with exercise and anxiety; the bradycardia associated with sleep.

Electrical conduction system The sinoatrial node (SAN) is the origin of the impulses responsible for normal heart rhythm (‘sinus rhythm’). The atrioventricular node (AVN) regulates the frequency of conduction to the ventricles - the delay in conduction between the SAN and AVN allows the ventricles to fill with blood as they depolarise, prior to ventricular contraction. From here the bundle of His fibres radiate out into the Purkinje network.

Heart valves and chambers There are four heart chambers: • right atrium • right ventricle • left atrium • left ventricle

These are separated by four main valves: • Two atrioventricular valves (tricuspid [left heart]; mitral [right heart]) • Two ventricular outflow valves (aortic; pulmonary)

Circulation During systole (atrial and ventricular contraction), blood is pushed through the heart chambers and into the pulmonary and systemic circulation. During diastole the heart muscle is relaxed and the heart fills with blood. Blood returns to the heart from organs and tissues down a pressure gradient with the help of the muscular pump (contraction of calf muscles pushes blood through venous valves) and the respiratory pump (‘bellows’ action of the diaphragm on the inferior vena cava). This venous return is also influenced by other factors such as blood volume and gravity. The circulating blood volume of an adult is 5-6 litres.

Cardiac output Cardiac output, the volume of blood circulated in one minute, is approximately 5 litres/min and is dependent on heart rate and stroke volume:

Cardiac Output = Heart Rate x Stroke Volume

Adult stroke volume is approximately 70mls at rest. It is dependent on end-diastolic pressure after the ventricles have filled with blood (preload) and peripheral resistance (afterload). Increased preload causes increased stretch of cardiac muscle fibres which results in increased force of contraction and increased stroke volume (Starling’s Law of the heart). As blood pressure falls, afterload falls so allowing greater shortening of cardiac muscle fibres, greater power of contraction and a corresponding increase in stroke volume. This system is under neuro-endocrine control and is affected by many drugs e.g.most anaesthetic drugs decrease the contractility of heart muscle.

Heart rate is modified by multiple factors, including: • pain and anxiety • vagal tone • endocrine system, e.g. thyroxine, adrenaline • chemoreceptors (hypoxia and hypercarbia) • baroreceptors (sensitive to fall in blood pressure)

Blood pressure The pressure generated by blood circulating in the major blood vessels is determined by cardiac output and peripheral resistance. ‘Normal’ blood pressure is 120/70 mmHg. In the management of patients with hypertension, the target clinic blood pressure is 140/80 mmHg (diabetic) or 140/85 mmHg (non-diabetic).

Blood Pressure = Cardiac Output x Peripheral Resistance

Blood vessel diameter, particularly small vessels, is controlled by the sympathetic nervous system and circulating catecholamines. An increase in sympathetic activity increases vascular tone while a decrease causes vasodilatation.

Factors affecting blood pressure

HYPERTENSION HYPOTENSION obesity drugs (antihypertensives and antianginals) smoking dehydration high salt/fat intake fitness family history normal pregnancy steroids anxiety recent exercise pregnancy (pre-eclampsia)

Arteries, veins and capillaries Arteries carry oxygenated blood from heart to organs in a pulsatile flow. This high-pressure system is a low-volume one, carrying only ~ 20% of circulating blood volume. Veins carry deoxygenated blood back to the heart and are a low-pressure, high-volume system, carrying ~ 75% of circulating blood volume. Gas exchange occurs in the capillary beds.

RESPIRATORY ANATOMY AND PHYSIOLOGY

The respiratory system comprises: • upper respiratory tract: nose, nasopharynx, larynx • lower respiratory tract: trachea, bronchi • lungs: respiratory bronchioles and alveoli

The lungs have a combined surface area of some 500m2 and are directly open to the outside environment.

The acinus (branching respiratory bronchioles and clusters of alveoli) is the unit of gas exchange. Blood flows through a rich capillary network intimately related to the acini, so facilitating gas exchange and ensuring that oxygen enters the bloodstream and carbon dioxide is removed. Optimal gas exchange relies on good ventilation and good perfusion of the lung fields.

Inspiration and expiration Inspiration is an active process in which muscle contraction works to enlarge the ribcage. The diaphragm is the main muscle of inspiration, assisted by the intercostal muscles. Expiration, however, is usually a passive process of elastic recoil of the lungs and chest wall. Active expiration involves abdominal muscles, diaphragm and intercostal muscles.

Lung capacities and volumes These depend on the size of the lungs and thorax and the degree of inspiratory/expiratory effort.

Tidal volume is the volume of air moved in one normal breath, usually ~ 500mls.

Respiratory rate is ~12 breaths per minute for an adult at rest.

Minute volume of ~6 litres/min is the volume of air moved in one minute of normal breathing (this is the volume that the flow rate of an inhalation sedation machine must meet

for each patient).

Minute Volume = Tidal Volume x Respiratory Rate

Vital capacity ~5 litres is the expiratory reserve volume (to maximum expiration) plus the inspiratory reserve volume (to maximum inspiration).

Functional residual capacity ~ 2 litres gives an estimate of oxygen reserve. It allows for breath holding and maintains the pressure of oxygen in the lungs, preventing lung collapse.

Dead space volume (~150 mls) is an estimate of the area of the respiratory system which is not available for gas exchange. If a patient is taking very shallow breaths, then tidal volume can < dead space volume, leading to little or no gas exchange. Shallow breathing commonly occurs with CNS depressants such as opioid analgesics and midazolam.

Composition of air CONSTITUENT INSPIRED EXPIRED AIR oxygen 20-21% 16% carbon dioxide 0 4% nitrogen 78% 78% water vapour yes yes

Gas exchange Gas exchange occurs down a diffusion gradient at the alveolar-capillary membrane which is some 0.06mm wide. Exchange rate depends on the concentration gradient as well as ventilation and perfusion ratios.

Oxygen is carried in blood almost entirely bound to haemoglobin, an iron-containing protein, each molecule of which has the capacity to carry four oxygen molecules. The haemoglobin molecule changes its stereochemistry with the bonding/debonding of each oxygen molecule. These stereochemical changes affect the affinity of haemoglobin for oxygen and result in the characteristic shape of the oxygen dissociation curve (the curve which represents the relationship between O2 partial pressure in the blood and the % saturation of haemoglobin with oxygen). The curve’s sigmoid shape means that a small drop in alveolar oxygen tension results in a large amount of oxygen being released into the tissues, keeping them maximally oxygenated.

Carbon dioxide is carried in solution in blood as bicarbonate ions which dissociate, liberating hydrogen ions. Any changes in CO2 levels will therefore result in pH changes.

Control of respiration Involuntary control of respiration is based in the respiratory centre within the medulla of the brain. The centre receives signals from chemoreceptors within the brain and major blood vessels, sensitive to rising carbon dioxide concentrations, and from stretch and irritant receptors within the lungs.

When chemoreceptors sense an increase in carbon dioxide (changes in blood pH), respiratory drive is increased (rate and depth of breathing). CNS depressants reduce the sensitivity of chemoreceptors.

Voluntary control of breathing involves the cerebral cortex sending signals to the muscles of respiration to override the autonomic nervous system.

CONCLUSION

A knowledge of basic cardio respiratory physiology is essential for the effective and safe practice of conscious sedation.

2 Principles of Pharmacology

Introduction The safe administration of any drug requires knowledge of its pharmacology. Pharmacology involves consideration of a drug’s pharmacokinetics and pharmacodynamics. Some useful definitions: • Pharmacokinetics – a description of drug absorption, distribution, redistribution, metabolism and excretion (how the body affects drugs). • Pharmacodynamics – a description of the effects of drugs (how drugs affect the body). • Half-life – the time it takes for the plasma concentration to fall to half its original value. Complete elimination involves removal of the drug from the receptor sites (sometimes called the redistribution half-life) and then metabolism and excretion (the elimination half-life). Redistribution time is usually shorter than elimination time. • First-pass metabolism – the portion of a drug which is broken down by the liver on first passage through the portal circulation (applies to orally-administered drugs).

The drugs most commonly used for dental sedation are the benzodiazepines (for oral, intravenous and transmucosal sedation) and nitrous oxide and oxygen (for inhalational sedation). Drugs which produce conscious sedation and analgesia may be administered by a variety of methods. The choice of route depends on the properties of the drug and how quickly a response is required. These include: • Intravenous • Inhalational • Oral • Transmucosal (intranasal/buccal)

Drugs administered parenterally (by injection) or by inhalation are quickly absorbed and usually act quickly. Oral absorption is unpredictable and time-consuming because the rate of gastric emptying is altered by anxiety, disease, other drugs and the presence of food, and drugs are also subject to first-pass metabolism. The transmucosal route can be almost as fast as the parenteral route. It is important to remember that whatever the initial route, all sedative drugs travel to their target sites via the systemic circulation.

A consideration of pharmacokinetics and pharmacodynamics is important when choosing the most appropriate drug for each individual patient.

Pharmacokinetics The degree of protein binding of a drug alters its availability. A portion of the drug dose is dissolved in plasma (the active form) whilst the rest is bound to plasma proteins and is not free to combine with receptor sites. Some disease processes change the proportion of bound drug. Similarly, two drugs can compete for the same binding site and thereby increase the free concentration of one or both agents. Either of these mechanisms may increase or decrease the expected clinical effects.

Drugs are eliminated by a variety of routes. Most of the inhalational agents used for sedation are excreted through the lungs. For benzodiazepines, the most important organs are the liver and the kidneys which metabolise and excrete these drugs. The measure of elimination of the drug is the half-life.

The properties and route of administration of different drugs determine the speed of absorption and distribution and hence the speed of onset of the sedative effect. A drug with rapid metabolism and excretion produces a swift recovery and earlier discharge for the patient.

Pharmacodynamics Pharmacodynamics describes the effect the drug has on the patient and includes both desirable and undesirable effects. The definitions of ‘desirable’ and ‘undesirable’ effects are not fixed but depend upon what one is trying to achieve. Most sedative drugs elicit a response via receptors which are specific to each drug. Receptors are located in cell membranes. All benzodiazepines have a common core structure with individual differences which determine their solubility and precise actions.

When drugs bind to receptors in the central nervous system these are altered, and the activity of the cell is either stimulated or inhibited. These drugs are called agonists. Midazolam is a benzodiazepine agonist. Drugs which act to displace agonists from the receptor sites thus terminating their effects are known as antagonists. Flumazenil is a benzodiazepine antagonist.

Properties of the ideal sedative drug: • Comfortable, non-threatening method of administration • Rapid onset • Predictable sedative/anxiolytic action • Controllable duration of action • Analgesic • No side-effects • Rapid and complete recovery

INTRAVENOUS SEDATION

Benzodiazepines The benzodiazepine group of drugs has a number of desirable pharmacodynamic properties which make these agents useful drugs for conscious sedation: These include: • Anxiolysis • Sedation • Muscle relaxation • Anterograde amnesia

For the sedationist, the most significant undesirable property of these drugs is respiratory depression, which is usually easily managed but requires careful monitoring. Although benzodiazepines have the potential to produce dependency, this is not a problem with the use of midazolam for conscious sedation.

Diazepam Diazepam produces excellent sedation and was for many years the drug of choice for dental sedation. However, it has a number of disadvantages which have resulted in its being superseded by midazolam.

Midazolam Midazolam is currently available as several injectable preparations which are stable in aqueous solution, and is non-irritant on injection. In line with current guidance, SAAD recommends the use of low concentration midazolam, which comes as a 5mg/5ml solution. The higher concentration formulations (10mg/5ml and 10mg/2ml) are not recommended as the risk of midazolam-related incidents is more likely. Midazolam should be titrated, which means administering the drug slowly in small-volume increments whilst assessing the patient’s response. This mode of administration ensures that patients receive an adequate but not excessive dose of the sedative agent. It is impossible to predict the correct sedative dose of intravenous midazolam for any individual patient on the basis of his weight, height, Body Mass Index or the apparent degree of anxiety.

Properties of midazolam

Water soluble Yes

Solvent Aqueous

Irritant No

Presentation 5mg/5ml, (10 mg/5 ml and 10mg/2ml although not recommnended for routine sedation) Distribution half-life 6-15 mins

Elimination half-life 1.5-2 hours

Usual dose 2-7.5 mg

Late active metabolites None

Analgesia No

Within the United Kingdom midazolam is available in several formulations. Traditionally, high concentration midazolam (10mg/2ml) was mixed with other liquids for oral use. However, alternatives are available in syrup form (2.5mg/ml) and should be used where advocated. Midazolam may also be administered intranasally via a Mucosal Atomisation Device attached to a 1ml syringe. Between 0.25mls and 0.3mls of 40mg/ml concentration is recommended. However, bolus administration needs to be approached with caution, particularly when treating older patients.

Temazepam Temazepam is no longer considered to be the drug of choice as an oral alternative for intravenous or inhalational sedation in the dental surgery. It may, however, have a place in the management of pre-appointment anxiety. For example, temazepam may be prescribed to ensure a satisfactory night’s sleep prior to a dental visit. It has been produced in various forms: tablet, gel-filled capsule, and an elixir for oral administration.

The different formulations have different rates of absorption, but temazepam is reasonably rapidly absorbed following oral administration. The sedative effects are usually clinically apparent for at least 45 minutes. Temazepam has a relatively short elimination half-life (5-11 hours) which makes it a useful drug for conscious sedation.

Flumazenil Flumazenil (Anexate) is a specific benzodiazepine antagonist. It has the same core structure as all other benzodiazepines. However, as it has a stronger affinity for the receptors than most agonists, including midazolam, it will displace them. Flumazenil reverses the anxiolytic, sedative and respiratory depressant effects of midazolam but has no clinically apparent sedative or stimulant effects. It does not reverse the anterograde amnesia induced by midazolam. Therefore, the loss of memory of unpleasant events which took place before reversal with flumazenil is retained. Flumazenil is used for the emergency reversal of sedation but can be used electively in selective cases (e.g. patients with learning disabilities or mobility problems). Reasons for its use must be justified and recorded.

Flumazenil has a shorter half-life than midazolam. However, ‘re-sedation’ is not a clinical problem as the cessation of action of flumazenil (approximately 50 minutes) coincides with the point at which patients would normally be expected to be fit for discharge. Allergy to the benzodiazepines is rare.

Mechanism of action of benzodiazepines Benzodiazepines act throughout the central nervous system. Specific benzodiazepine receptors are located on nerve cells within the brain. All benzodiazepine molecules have a common core shape, which enables them to attach to these receptors. The effect of attaching benzodiazepines to cell membrane receptors is to alter an existing physiological 'filter'.

The normal passage of information from the peripheral senses to the brain is filtered by the GABA system. GABA (gamma-amino-butyric acid) is an inhibitory neurotransmitter which is released from sensory nerve endings as a result of nerve stimuli passing from neurone to neurone. When released, GABA attaches to receptors on the cell membrane of the post-synaptic neurone. This stabilises the neurone by increasing the threshold for firing. In this way, the number of sensory messages perceived by the brain is reduced.

Benzodiazepine receptors are located on cell membranes close to GABA receptors. The effect of having a benzodiazepine in place on a receptor is to prolong the effect of GABA. This further reduces the number of stimuli reaching the higher centres and produces pharmacological sedation, anxiolysis, amnesia, muscle relaxation and anticonvulsant effects.

All benzodiazepines, which are central nervous system depressants, have a similar shape with a ring structure on the same position of the diazepine part of each molecule. By contrast, flumazenil, the benzodiazepine antagonist, does not have this ring structure and has a neutral effect on the workings of the GABA system. Flumazenil is an effective antagonist, as it has a greater affinity for the benzodiazepine receptor than the active drugs and therefore displaces them.

Metabolism of benzodiazepines takes place in the liver. Midazolam has no metabolites which are active once the parent drug has been removed. The water-soluble metabolites of the benzodiazepines are excreted via the kidneys.

The anterograde amnesia produced is a desirable effect in terms of reducing the patient’s memory of treatment but, paradoxically, is less helpful when trying to ‘wean’ patients away from treatment under sedation. The most profound amnesia occurs immediately after induction, but some disturbance to short-term memory may persist for several hours or even until the following day.

The muscle relaxant effect of benzodiazepines contributes to the difficulty in standing, walking and maintaining balance experienced by many patients following treatment.

Respiratory effects of benzodiazepines Benzodiazepines produce respiratory depression. This is usually mild in healthy patients if the drug is administered intravenously by slow titration. It can, however, be a significant problem in unwell or elderly people. Even in a fit, healthy individual, a fast injection or a large quantity of midazolam has the potential to depress respiration to the point of apnoea.

There are two mechanisms by which ventilation is depressed. First, relaxation of the muscles of respiration causes a dose-related reduction in the rate and depth of breathing. Second, the reduction in sensitivity of the central carbon dioxide and oxygen chemoreceptors decreases the ability of the respiratory centre to increase the respiratory drive in the presence of hypercarbia and/or hypoxia.

Benzodiazepine-induced respiratory depression affects all patients who are sedated with these drugs by any route of administration. For this reason, it is important to monitor respiration and oxygen saturation levels throughout sedation, particularly with intravenous sedation, but also after the oral or transmucosal administration of benzodiazepines.

Cardiovascular effects of benzodiazepines Benzodiazepines have few significant effects in healthy people. There is a decrease in mean arterial pressure, cardiac output, stroke volume and systemic vascular resistance. This may present as a small fall in arterial blood pressure immediately following induction of sedation. However, this is normally compensated by the baroreceptor reflex and is of negligible clinical significance, except in people with compromising cardiovascular disease.

Propofol Propofol (Diprivan 1%) is a synthetic phenol anaesthetic induction agent which was introduced into clinical use in the 1980s. It is extremely lipid soluble but virtually insoluble in water. Each 20ml ampoule contains 200mg of propofol (10mg/ml). The solution is sometimes painful on injection particularly when a small vein is used.

The pharmacokinetics of propofol make it an ideal agent for certain dental procedures. The redistribution half-life is approximately two to four minutes. In order to maintain sedation at a constant level, it is therefore necessary to administer propofol by continuous infusion. Metabolism takes place in the liver and metabolites of propofol are excreted by the kidneys. The elimination half-life is about 60 minutes in fit patients.

Propofol is very useful for short procedures when sedation is required for only a few minutes, for example, in the extraction of a single tooth. Recovery occurs rapidly after the drug is discontinued. It may also be used for longer cases, particularly when only light sedation is required.

Propofol tends to depress respiration. The frequency of hypersensitivity reaction is similar to that of other anaesthetic induction agents. As its margin of safety is narrower than midazolam, propofol should be used only by those trained in advanced sedation techniques.

Opioids For some patients, the use of a single agent does not provide an adequate degree of sedation to enable treatment to be provided. In these cases, a combination of agents may make treatment possible, thereby avoiding the need for general anaesthesia. The most frequently used combination of agents is an opioid and midazolam. Individual opioids, like benzodiazepines, act through CNS receptors and have either agonist or antagonistic actions. These drugs produce a number of therapeutic effects including analgesia, sedation and euphoria. Their undesirable effects include cardiorespiratory depression and nausea and vomiting. The most important of these in relation to conscious sedation is respiratory depression. Great care must always be taken when a combination of an opioid and a benzodiazepine is used for sedation.

If an opioid is used for sedation, the opioid antagonist naloxone (Narcan) must be available. Naloxone is a pure opioid antagonist and reverses respiratory depression, analgesia and sedation.

INHALATIONAL SEDATION

Inhalational agents are commonly used for dental sedation. Traditionally nitrous oxide has been the only gas used. Volatile anaesthetic agents are now being investigated and may have a role to play in the future.

Nitrous oxide Nitrous oxide is rapidly absorbed. The rate of absorption depends on a number of factors including the solubility of the drug in blood. Agents with a low solubility produce a rapid onset of sedation because the concentration of the drug in the blood, and therefore in the brain, rapidly equilibrates with the inspired concentration. When the agent is discontinued, recovery occurs quickly as the concentration of the agent falls.

The Minimum Alveolar Concentration (MAC) is a value (obtained experimentally) which represents the potency of an inhalational agent. Nitrous oxide has a high MAC, in contrast with most volatile anaesthetic agents. A high MAC indicates an agent of low potency, which is ideal for conscious sedation. In the UK, nitrous oxide is supplied in blue cylinders containing both gaseous and liquid phases under high pressure (5400 kPa or 800 psi).

Properties of nitrous oxide

Induction/recovery Rapid and smooth

Potency (MAC) Weak (105%)

Blood gas solubility Low (0.47)

Metabolism <1%

Usual dose 20-40%

Analgesia Yes

The nitrous oxide molecule is excreted unchanged almost exclusively by the lungs. It is therefore suitable for patients with (even advanced) liver or kidney disease. It has little effect on the respiratory system as it is non-irritant and does not increase bronchial secretions nor does it depress respiration centrally. The cardiovascular effects of nitrous oxide are insignificant in healthy patients.

The inspired concentration at which sedation occurs varies from patient to patient; in some people 70% nitrous oxide has no effect whereas in others (especially the elderly) 25% may produce unconsciousness, with loss of airway-protective reflexes. Traditionally, three 'Planes of Relative Analgesia' are described, based on Guedel's Stages of General Anaesthesia.

Planes of Relative Analgesia

Plane I Moderate sedation and analgesia. Usually obtained with concentrations of 5-

25% N2O Plane II Dissociation sedation and analgesia 20-

55% N2O

Plane III Total analgesia 50-70% N2O

Planes I and II are clinically useful for dental sedation but plane III is generally considered to be too close to general anaesthesia to be safe.

The low solubility of nitrous oxide in blood and tissues results in a rapid outflow of nitrous oxide across the alveolar membrane when the incoming gas flow is stopped. This reduces the percentage of alveolar oxygen available for uptake by up to 50%. This phenomenon, diffusion hypoxia, may be counteracted by giving 100% oxygen for two minutes at the end of the procedure.

Long-term occupational (or recreational) exposure to nitrous oxide is an area of increasing concern. Biochemical, haematological, neurological and reproductive side-effects have been reported. Nitrous oxide produces reversible inhibition of the enzyme methionine synthetase which is involved in the synthesis of vitamin B12. Clinically significant bone marrow depression can be detected after as little as six hours' exposure to 60% nitrous oxide (or after much lower percentages for much longer periods of time). Nitrous oxide has also been linked to an increase in the rate of miscarriage among dentists and dental nurses.

Effective waste gas scavenging (active scavenging at 45 l/m) appears to reduce the risks and daily exposure to very low concentrations (<100 ppm) is unlikely to cause serious problems. Regular (yearly) monitoring of staff exposure levels to nitrous oxide is necessary to ensure low exposure levels and a Time Weighted Allowance of <100ppm.

There are also concerns about the possible harmful effects of nitrous oxide on the environment, notably ozone-depleting ‘greenhouse gas’ effects.

The greatest potential danger when using inhalational sedation is the failure to deliver an adequate supply of oxygen to the patient, due to inappropriate or faulty equipment. No correctly maintained inhalation sedation machine should be capable of administering less than 30% oxygen. The air entrainment valve in the machines ensures that a minimum of 21% oxygen (from room air) is delivered in the event that the machine fails to deliver O2.

Sevoflurane Sevoflurane is a fluorinated derivative of methyl isopropyl ether which was first synthesised in the early 1970s. Sevoflurane has a MAC of 2% and a low blood gas solubility (0.6). These physical characteristics make sevoflurane a potent anaesthetic agent with rapid uptake and speedy recovery. It is used extensively in day case surgery where rapid recovery is important. It is pleasant to inhale, non-irritant and non-pungent.

The properties that make sevoflurane a useful anaesthetic agent also make it a promising sedation agent. However, a specially calibrated vaporiser is required in order to titrate low concentrations of sevoflurane (up to 1%) in oxygen (or nitrous oxide and oxygen). Sevoflurane is partly metabolised (5%) and so some care is required in people with severe liver or kidney disease.

At present, sevoflurane is not widely used for dental sedation because of the practical problems associated with attaching a vaporiser to any of the currently available inhalational sedation machines.

CONCLUSION

When selecting drugs, it is important to know and understand their clinical effects. This is the key to safe, effective conscious sedation.

3 Patient Assessment and Treatment Planning

Introduction A satisfactory first visit is crucial to the success of subsequent treatment under sedation. There is a great deal of information to be acquired from the patient. At the same time, it should never be forgotten that the patient is assessing the operator too! The first meeting should ideally be out of the surgery environment (although this is not often possible) and in the nature of an informal “chat”. Assessment should be done at a separate appointment but may need to be just prior to treatment if there is a need for urgent intervention.

The following points need to be covered:

Find out the problem It is often helpful to get the patient to complete a questionnaire asking the nature of their fears (see below). It breaks the ice, and other questions may be included so as to assist in steering the conversation in the right direction. A discussion of the reasons for being frightened of dentistry can be lengthy and occasionally upsetting. Be positive and try not to dwell on the unpleasant past. Criticism of previous dentists should be listened to but not necessarily acknowledged. Needle phobia is a common condition that requires some elaboration regarding patients’ acceptance of venepuncture.

The use of the Modified Dental Anxiety Scale (MDAS) can also be a useful tool to gauge the level of dental anxiety (Appendix 1). This questionnaire forms part of the Index of Sedation Need (IOSN) – a toolkit that can be used to help justify the use of sedation.

Medical history A full medical history should be taken in the same way as for all patients. From the sedation point of view, special note should be made of respiratory and cardiovascular problems, liver and kidney disease, psychiatric disorders and pregnancy. Drugs regularly taken can alert the operator to undisclosed conditions and raise the possibility of potential drug interactions. Some medicines can potentiate the effect of sedation drugs. Special note should be made of CNS depressants (including benzodiazepines), and antihypertensives (e.g. beta-blockers). The use of recreational drugs, including alcohol, tobacco and cannabis, should be enquired into. In some cases, it may be advisable to discuss the patient’s medical history with the General Medical Practitioner or hospital consultant. The ASA classification may be helpful in determining suitability of patients undergoing conscious sedation. Generally speaking, patients who are ASA I and II are suitable for treatment in primary care. More complex patients may need to be referred to community or hospital settings.

Dental history The patient’s experiences at the dentist over the years are important. We need to discover: • Whether they were able to have normal dentistry in the past • When they first became fearful of dentistry, and what provoked the fear • When they last visited the dentist • Whether they have had sedation before • What concerns them most about their teeth • Whether they are having symptoms from teeth

Social factors The patient’s domestic circumstances are relevant, as an escort is going to be required for sedation appointments. In addition, responsibilities such as children or elderly parents may make it difficult for some patients to attend and to recover safely at home. It should be emphasised that escorts must be able and reliable enough to care for the patient for the entire period of home recovery.

Examination Whilst some patients will allow a full intra-oral examination, the operator may have to be content with a visual examination only (no probe or blowing on the teeth). For a very few patients, intraoral radiographs may have to be postponed until a later date when the patient is sedated. Panoral techniques are usually accepted and can give valuable information at this early stage.

Discussion Once a preliminary treatment plan has been established, the following treatment options can be discussed with the patient:

• LA alone

• Cognitive Behavioural Therapy

• Inhalation sedation

• Intravenous sedation • Oral or transmucosal sedation • Combinations of the above • GA

A description of the types of sedation available should then follow. The reaction from the patient at this stage is important in deciding which sedation technique is most appropriate. The simplest technique which will enable treatment to be carried out, is generally the best.

Finally, as part of your pre-operative checks;

• Record: o Blood pressure o Oxygen saturations o Respiratory rate o Heart rate o BMI • Examine veins (if appropriate). • Get consent form signed (consent to include discussion of benefits, risks, and alternative options). • Give written and verbal instructions for both patient and escort (see below). • In general practice, a written provisional treatment plan with fees should be given to the patient. • Make appointment.

Treatment planning A preliminary treatment plan may have to be significantly altered once the degree of cooperation has been ascertained after the first sedation appointment. In addition, the patient’s oral hygiene and dental aspirations may improve once treatment is under way and the patient realises that dentistry is possible after all! It is best not to promise advanced restorative procedures until after the first sedation visit.

The first visit should be one of confidence building. Choose a procedure that is achievable, of considerable benefit to the patient (relief of pain or restoration of appearance), and predictable. It may be desirable to prescribe GA for some procedures (e.g. surgical removal of teeth that are not restorable) and to complete restorative treatment with sedation. In these cases, it may be preferable to provide initial treatment with sedation to find out level of cooperation as this may alter the treatment plan for GA. Some patients may prefer inhalation sedation for fillings and intravenous sedation for extractions.

Patient management Remember that patients selected for either inhalational sedation (IS) or intravenous sedation are more than usually anxious about dental treatment and may also have specific fears (e.g. the dental drill, pain, injections, loss of self-control). All the procedures must therefore be carried out in a particularly careful and considerate manner, e.g. reassuring explanations and the use of topical analgesia before the administration of LA. Remember, too, that in most children and in many adults, sedation (especially IS) may be used to facilitate behaviour modification so that the patients can learn to overcome their fears and phobias. Sedation should never be allowed to take the place of good patient management and satisfactory pain control.

Instructions

Before sedation: on the day of treatment • Take your routine medicines at the usual times • Have only light meals and non-alcoholic drinks (up to two hours before your appointment) • Bring a responsible adult with you to the surgery to escort you home and care for you afterwards

After sedation: until the following day • Do not travel alone – travel home with your escort, by car if possible • Do not drive or ride a bicycle • Do not operate machinery • Do not drink alcohol • Do not return to work or sign legal documents • Do not look after young children or adults who require personal care • Avoid internet use

CONCLUSION

Patient assessment can be the most challenging part of providing a sedation service. Carrying out the assessment in a structured way at a separate appointment is more likely to be successful. Planning dental care under sedation requires a different approach from treatment under local anaesthesia for a non-anxious person.

4 Local Analgesia: Tips and Techniques

Introduction The success of conscious sedation depends on the success of local anaesthesia. This section of the course aims to provide some tips that will help the successful use of conscious sedation rather than turn the participant into an expert in local anaesthesia.

Pain and anxiety are interrelated. Anxiety influences the perception of pain, and painful experiences can increase anxiety. Many patients will give a history of a painful experience as provoking anxiety. Commonly reported problems are related to failure of local anaesthesia and intravascular injection. More sedation appointments will fail as a result of inadequate local anaesthesia than as a result of inadequate sedation.

LOCAL ANAESTHETIC TECHNIQUES IN SEDATED PATIENTS

When to give the LA? This surprising question is frequently asked. Fear of injections is one of the most common anxieties in dentistry. The local anaesthetic is given when the patient is sedated and ready for treatment. It is possible to test for the efficacy of local anaesthesia on a sedated patient.

The use of topical LA Patients who are sedated with midazolam will often react to painful stimuli in a more extreme manner than “normal” patients. This can result in hyperactivity, crying or movements away from the painful stimulus. It is beneficial to give local anaesthetic injections as painlessly as possible. The use of topical anaesthesia is an effective way of reducing the pain of local anaesthetic injections. The following are available for use in dentistry: • Lidocaine 2% gel • Lidocaine 5% ointment Lidocaine 10% spray • Benzocaine 20% gel

The benzocaine topical has two main advantages: 1. It is more rapidly effective 2. It is poorly absorbed into the systemic circulation, and thus does not contribute to systemic toxicity

Choice of local anaesthetic The gold standard is still lidocaine with epinephrine (adrenaline) as the vasoconstrictor

• Lidocaine 2% with 1:80,000 epinephrine Effective in 2-3 minutes (infiltration) Duration approximately 45-60 minutes

Maximum dose 4.4mg/kg up to 300mg absolute maximum • Prilocaine 3% with 0.03 IU/ml felypressin Slower onset than lidocaine Similar duration of action Maximum dose 6mg/kg up to maximum of 400mg

• Mepivacaine 3% plain or 2% with 1:80,000 epinephrine Causes least vasoconstriction so can be used plain Duration of action 30 minutes More effective for block than infiltration Maximum dose 4.4mg/kg up to 300mg absolute maximum

• Articaine 4% with 1: 100,000 or 1:200,000 epinephrine Short half-life due to metabolism in plasma Serial use has lower toxicity than other agents Although non-surgical paraesthesia with inferior alveolar nerve blocks (IANBs) has been reported, there is evidence that these can also be produced by other local anaesthetic solutions. Opinion is divided as to whether there is an issue administering IANBs. Evidence of greater efficacy of articaine is just starting to emerge to support the clinical impression that it is more effective for infiltration over upper incisors and as an adjunct to IANBs when used as a buccal infiltration.

Maximum dose 7mg/kg

Techniques of local anaesthesia under sedation Anaesthesia is achieved in the same way as if the patient was not sedated. If a patient would require LA for treatment if they were not sedated, then they will also require LA for the same treatment under sedation. Any number of quadrants, can be anaesthetised , provided this stays within the maximum dose of LA.

Can use bilateral IAN Blocks • Unpleasant for the patient post-operatively • No risk of airway problems (posterior third of tongue has different innervation) • Allows decreased number of visits (removal of all four wisdom teeth in one visit) • Use can be reduced by using incisive (mental) nerve block when indicated • Intraligamentary LA particularly useful for extractions under inhalation sedation • Can cause postoperative pain when used for restorative treatment • Success is tooth-dependent

Does inhalation sedation provide enough anaesthesia to allow dental treatment? Nitrous oxide is a good analgesic, particularly for ischaemic muscle pain. It is less effective for the control of operative pain.

Overdose of nitrous oxide is unpleasant, and thus increasing the amount of nitrous oxide used to try and avoid the use of local anaesthesia should be approached with great caution.

Testing efficacy of local anaesthesia It is possible to test for the efficacy of local anaesthesia on sedated patients. Patients are also able to distinguish differences between sides (for example where an IAN Block has been given).

Local anaesthetic toxicity The best management for local anaesthetic toxicity is prevention. The best way of preventing toxicity is to stick to the maximum safe doses, remembering that the toxic effect of different local anaesthetics is an additive effect. Thus if 50% of the maximum dose of lidocaine is used and the operator wishes to add another local anaesthetic, they can only use 50% of the maximum dose of the second agent.

Toxicity can also be caused by a relative overdose if a large bolus of local anaesthetic enters the bloodstream. This is usually caused by an intravascular injection. This is best prevented by the use of syringes capable of aspiration for all injections.

Other considerations The amnesia produced by benzodiazepine sedation means that patients are unlikely to remember the administration of local anaesthesia. This coupled with the fact that many of the patients have little experience of dental treatment means that there is a greater need to warn patients regarding the effects of local anaesthesia and in particular the hazard of lip biting whilst still under the influence of benzodiazepines.

TOPICAL SKIN PREPARATIONS

There are two preparations available for topical skin anaesthesia to reduce the discomfort of intravenous cannulation.

EMLA Eutectic mixture of local anaesthetics. This preparation contains 2.5% lidocaine and 2.5% prilocaine. Onset of acceptable anaesthesia takes 60 minutes under an occlusive dressing. Side- effects: - profound vasoconstriction.

Ametop Amethocaine gel. This is an ester-type local anaesthetic. Onset of acceptable anaesthesia takes 45 minutes under an occlusive dressing. Side-effects: - skin reactions are common. Many patients have erythematous reactions, particularly if the preparation is on for longer than 45 minutes.

Clinical use Both preparations provide good topical anaesthesia of the skin. In clinical practice, they are probably more useful in children than adults. In adults the anxiety regarding cannulation is more about the process rather than the pain, and adults are less easy to distract. In children, effective distraction can be achieved if the topical anaesthetic is placed on both hands and the occlusive dressing is removed from the second hand as the first is cannulated. If topical skin anaesthesia is used regardless of which preparation is used, the author would advocate that the patients are taught to apply the gel and dressing so that excessive waiting in the dental environment is avoided.

An alternative is to use inhalation sedation with nitrous oxide. This has the advantage that in addition to analgesia, anxiolysis and vasodilation are produced.

USEFUL ADJUNCTS

Oraqix This product is a periodontal gel containing 2.5% lidocaine and 2.5% prilocaine. These are the same active agents as in EMLA. Oraqix is a thermosetting preparation designed to be used in periodontal pockets. It produces anaesthesia of the gingival tissue. There is sufficient anaesthesia to allow probing and scaling and root planing. The use of Oraqix can allow some needle-phobic patients to undergo nonsurgical periodontal treatment without recourse to conscious sedation.

If used in combination with conventional local anaesthesia, the dose of Oraqix must be included in the calculation of the maximum permissible dose. • Oraqix is a non-injectable dental local anaesthetic indicated in adults for localised anaesthesia in periodontal pockets for diagnostic and treatment procedures • Oraqix was launched in the UK in November 2005.

Computer controlled LA delivery systems There are two computer-controlled LA delivery systems – the Wand and the C Syringe. Both have the advantage of controlled pressure of delivery resulting in a more comfortable experience for the patient.

There are new techniques of LA administration possible with these devices, which reduce the amount of local anaesthetic required and the amount of soft tissue anaesthesia produced. Detailed descriptions of these techniques are beyond the scope of this course.

The Safety Plus system This is a system that removes the need to re-sheath LA needles. In theory this reduces the incidence of needle stick injuries. This system is being increasingly adopted in dental schools and primary care settings.

CONCLUSION

Effective local anaesthesia is of fundamental importance to the practice of conscious sedation in dentistry. More sedations probably fail as a result of poor LA than any other factor. An understanding of the maximum safe dose of LA which can be used allows the maximum benefit to be achieved at each sedation appointment. Local anaesthesia is still an advancing area.

5 Intravenous Sedation with Midazolam

Midazolam is almost the ideal drug for dental sedation.

Advantages of IV sedation with midazolam: • Rapid onset (five minutes or less) • Good patient co-operation • Good amnesia • Reasonably wide safety margin

Disadvantages of IV sedation with midazolam: • No clinically useful analgesia • Respiratory depression • Occasional disinhibition effects • Post-operative supervision for a minimum of eight hours is required • Elderly patients are easily over-sedated

INDICATIONS AND CONTRA-INDICATIONS

Indications: • Moderate to severe anxiety in adults and children • Unpleasant procedures e.g. oral surgery • Medically compromised patients e.g. angina • Hypersensitive gag reflexes • Patients with learning disabilities and challenging behaviour • When other sedation methods are contra-indicated • As an alternative to GA

Contraindications: The only absolute contraindication to the use of midazolam is allergy to any benzodiazepine. Fortunately, this is very rare.

In the following circumstances care and caution are needed: • Pregnancy and during breast-feeding. Midazolam should not be administered to a pregnant patient due to its effects on the unborn child. It is also excreted in breast milk so if a breast- feeding mother requires IV sedation she should not feed her child for eight hours post- sedation • Severe psychiatric disease, alcohol or drug abuse. The effects of IV sedation are unpredictable in people with mental health disorders or those accustomed to high levels of alcohol or illicit drugs. While they can be sedated these are not suitable patients for the inexperienced sedationist • Impairment of hepatic or renal function. People with reduced liver and kidney performance may take longer to metabolise and excrete midazolam

• Needle phobia. Here the success of treatment depends on the degree of phobia. Some patients may be able to accept cannulation with the application of topical anaesthetic cream (EMLA or Ametop) and / or nitrous oxide. Other more extreme phobias may require administration of midazolam orally or intra-nasally followed by cannulation. • Doubts about the ability to provide a suitable escort. A sedated patient must be taken home by a suitable escort who can stay with the patient until the evening. A patient cannot be sent home alone even by taxi. If they cannot provide an escort, then IV sedation cannot be offered. Most people faced with this ultimatum will find someone to accompany them. If not, alternative treatment options need to be considered

Patient checks before sedation On arrival the receptionist should ensure that a suitable escort is present. If the patient is known to the practice, then it may be acceptable to have a contact number to call the escort at discharge time. In other settings, it is better to ensure the escort is present before beginning sedation and ask them to wait.

The medical history and consent should be confirmed and pre-operative checks recorded – blood pressure, oxygen saturations, heart rate and respiratory rate. It is not necessary to starve before single drug IV sedation but for their comfort it is wise that the patient avoids eating for up to two hours before the appointment. Some sedationists like to give a glucose drink to patients who have starved.

Different practitioners have different approaches to alcohol before sedation. While it would be ill- advised to sedate someone who is drunk, some patients need the help of alcohol to reduce their anxiety before dentistry. Patients should also be asked to visit the lavatory before treatment.

Equipment These drugs and equipment should be made ready before the patient enters the surgery.

• Midazolam (5mg in 5ml) • Alcohol wipe • Flumazenil • Adhesive to secure cannula • Safety cannula • Tourniquet • 5 or 10 ml syringe for midazolam • Pulse oximeter • Midazolam label • Means of recording blood pressure • Blunt 21g drawing-up needle • Oxygen and nasal cannula • Saline • Cotton wool roll • Separate syringe for saline • Plaster • Saline label

Cannulation Novice sedationists are often anxious about achieving venous access. It is a skill which develops with time and although a description and practical advice are given here it does require lots of practice.

Any reasonably large vein can be used. Those most commonly used are the cephalic or median cephalic veins of the ante-cubital fossa and the superficial metacarpal veins of the dorsum of the hand. In situations where no veins can be palpated, the dorsum of the feet may be used. Experienced operators often have a preferred site as will some patients.

A tourniquet can be used to occlude venous return and make veins more prominent but it is sometimes more pleasant if an assistant maintains a steady grip around the limb, proximal to the intended point of cannulation. It also reduces the chance of the patient moving as the needle approaches. Pressure must be firm enough to prevent venous return but must not occlude the arterial supply. The venepuncture site must be below the level of the heart in order to encourage venous pooling. Patients who are cold and frightened may appear to have no veins. Gentle tapping over the site of the vein or placing the patient's hands in warm water can help. As a last resort, a sphygmomanometer cuff, inflated to a pressure between systolic and diastolic blood pressures can be used. It is worth taking time to locate a good vein, checking all four sites if necessary before selecting the best one. The use of inhalation sedation with nitrous oxide can help increase vasodilation and hence cannulation.

Most operators use a small, or a dual port IV catheter system such as BD Nexiva (20 - 24 g) safety cannula. Butterfly needles are no longer considered appropriate as the lumen rapidly becomes occluded by clotted blood thus making the administration of emergency drugs difficult or impossible. Butterfly needles also have a habit of ‘cutting out’ of the vein. While injecting the drug, the patient should be asked if any discomfort is felt. Also, care should be taken to ensure that the cannula remains within the vein during administration by securing it with non-allergenic tape. Saline can be used to flush through the cannula and check correct siting.

Method of administration Induction should be carried out with the patient lying supine. The pulse oximeter should be in place before induction and the reading noted. Supplementary oxygen and nasal cannulae must be available for use and, for some medically compromised people, should be in place before induction eg patients with angina.

It is not possible to determine the correct dose of midazolam on the basis of the patient's body weight or age and a titration technique is required. The dose will also vary for the same patient on different occasions.

The following regimen is appropriate for most fit adult patients: • 2 mg of midazolam over 30 seconds • Wait 90 seconds and observe the effect • Increments of 1 mg midazolam are then given at 30 second intervals until adequate sedation is achieved.

Care should be employed when sedating older people (>65) – think about both chronological and biological age. There is reduced plasma protein binding of drugs meaning that there is more free drug available to cause a sedative effect. The regime above should be adjusted in the elderly: • 1mg of midazolam • Wait four minutes to allow a longer circulation time • Additional increments of 0.5mg every two minutes

Some older patients are adequately sedated on as little as 2mg of midazolam.

Signs of sedation There is no specific end point to determine when a suitable sedation level has been achieved but the following are good indicators: • General muscle relaxation • Relief of anxiety • Drowsiness • Slurred speech • Slowed responses • Decreased motor coordination

It is an overall clinical impression, but another useful sign is how well the patient accepts the injection of local anaesthesia. Verbal contact must be maintained throughout treatment.

Maintenance of sedation Sedation usually lasts for 20-30 minutes but may be prolonged by further small increments of midazolam (e.g. 1 mg) titrated against the patient's response. This is particularly useful for long cases such as implant surgery when small increments can be given every 10 minutes or so.

If a patient ceases to respond to verbal command, treatment must be stopped immediately, the chair made horizontal and the patient's breathing supported until verbal contact returns. Loss of verbal contact means loss of consciousness, a potentially serious situation which requires maintenance of the airway and administering positive pressure ventilation with oxygen via a self-inflating bag. It should never happen when sedation is induced carefully using the method of titration described above with strict adherence to the intervals between increments.

In case the patient experiences a sexual fantasy, it is essential that a dental nurse or other chaperone is present at all times during the period of sedation and recovery.

Reversal of midazolam sedation Flumazenil reverses the sedative, cardiovascular and respiratory depressant effects but not the amnesic effects of midazolam. Flumazenil has a shorter half-life than midazolam. In spite of this, clinically significant re-sedation does not occur when midazolam is used for short clinical procedures. Elective reversal with flumazenil may occasionally be indicated for individuals who take longer than normal to recover, for a patient who has a difficult journey home or for a patient who has mobility difficulties. It should not be used routinely to reverse patients.

At the end of treatment When treatment is completed, the patient must be kept under observation and monitored either in the surgery or in a properly equipped recovery area, until able to stand and walk without assistance. The recovery area should be separate from the waiting area and have somewhere for the escort to stay with the patient, as well as appropriate monitoring equipment, including; pulse oximeter, blood pressure monitor, oxygen, portable suction and a recovery chair /bed capable of going into a head tilt position if required.

Discharge For the majority of patients, it is usual to wait at least one hour after the last increment of drug was administered before assessing the patient for discharge. However, discharge must be based on an individual patient assessment.

Discharge criteria include: • walking without assistance • oxygen saturations returned to baseline • blood pressure back to near baseline • speech no longer slurred

Patients must only be discharged into the care of an escort, who must be given written and verbal instructions. Although the dental nurse may give postoperative advice it is the dentist’s responsibility to ensure the patient is fit for discharge and meets discharge criteria. The cannula should be removed just before discharge, not at the end of the procedure. Pressure should be applied to the injection site to avoid a bruise.

Multiple drug sedation For a few patients, single drug sedation does not provide sufficient cooperation and it is not possible to provide dental care. For these people multiple drug sedation may be considered. Using additional drugs such as opioids can increase the depth of sedation but also increases the risk of respiratory depression. Alternative drugs like propofol may provide better sedation for some patients. The use of these alternative techniques requires the practitioner to have suitable training and experience. Further description of the available drugs is covered in Chapter 10.

CONCLUSION

Intravenous sedation is safe, effective and easy to administer for the majority of anxious patients.

6 Inhalational Sedation (IS) Aka Relative Analgesia (RA)

PROPERTIES AND PRESENTATION OF NITROUS OXIDE

• A non-irritant, virtually odourless and colourless gas • A weak anaesthetic with a MAC of 105% • It is heavier than air • Produces anxiolysis, mood alteration, muscle relaxation and analgesia with little amnesia • Suppresses gagging but does not abolish protective reflexes like coughing • Has little in the way of side-effects in therapeutic doses • Is easily administered, rapidly acting and eliminated • Is suitable for all age groups • Has a wide margin of safety • Presented in blue cylinders compressed at 800 lb/in2 (43.5 bar) • Compressed, it is a liquid within the cylinders and sublimates to a gas on delivery

INDICATIONS AND CONTRA-INDICATIONS

Indications • Mild to moderate anxiety in adults and children • Unpleasant procedures in patients with low treatment experience • Medically compromised patients • Needle phobia • Gag reflexes • When other sedation methods are contra-indicated • As an alternative to GA (e.g. orthodontic extractions)

Absolute contra-indications • Acute and chronic nasal obstruction • First trimester of pregnancy • Inability to co-operate or understand – age or disability • Where the nasal hood and tubing makes it impossible to access the operating site/field

Relative contra-indications • Inability to breathe nasally with open mouth • Severe chronic obstructive airways disease – cyanosis at rest where respiratory drive may be dependent on low blood oxygen tension • Nasal or facial deformity

• Severe forms of medical conditions like Motor Neurone Disease, Parkinson's Disease, Myasthenia Gravis and Multiple Sclerosis • Severe psychological disorders and nasal hood phobia • Recent ocular surgery (due to risk of mild rise in intraocular pressure during IS) • B12 deficiency • Caution with patients on methotrexate therapy

Requirements The properties of nitrous oxide and its sedation technique easily conform to the definition of conscious sedation for dentistry. Inhalation sedation requires almost all the same medico-legal requirements as intravenous sedation, with the exception of the issue of escorts. Strictly speaking an escort is not an absolute requirement but the clinician needs to carefully assess whether one is required depending on the patient’s circumstances. Clinicians must have: • Undergraduate and/or postgraduate training and trained second appropriate person • Written, informed consent • Specific sedation assessment • Specific sedation contemporaneous record-keeping • Discharge criteria with written pre- and post-operative instructions • Health and safety requirements

ADVANTAGES AND DISADVANTAGES OF INHALATION SEDATION

Advantages • It is a non-invasive, simple technique (no extra needles for the patient) • It is suitable for all age groups • It has a rapid onset and the drug level is easily adjusted • It has few side-effects and sedation is easily discontinued • It is entirely excreted via the lungs, so recovery is rapid • No fasting is required • It provides some analgesia – generally soft tissue (not hard tissue) • It is very useful in patients with hypersensitive gag reflexes • Non-addictive • Useful for long procedures as the sedation is constantly supplied throughout

Disadvantages • It may not be suitable for severe anxiety • There is a degree of ‘technique dependence’ that requires psychological support • The amnesia is variable • Route of administration close to operating site • Nitrous oxide pollution risks

• Initial equipment set-up and maintenance costs • May cause nausea/vomiting at high doses

Equipment There is a wide range of dedicated inhalation sedation equipment available from several suppliers. • Piped or portable systems are available dependent on funds. Portables approx. £3600 + • Active scavenging systems are recommended • Plan the service costs into the financial assessment • Health and safety issues re: bottle carriage, storage and COSHH documentation • Peripheral costs include nasal hoods and tubing dependent on whether reusable or disposable systems are chosen

All portable systems are similar in that they contain a bottle-carrying device with a gas delivery head attached. The head contains the pressure-reducing valves and must be serviced annually. Each head unit has a flow dial and flow meter tubes for oxygen and nitrous oxide, mixture dial, air entrainment valve, oxygen flush button, pressure gauges and common gas outlet. Tubing and nasal hood systems vary dependent on the type of scavenging used. Portable equipment generally uses ‘E’ sized cylinders (680 litres oxygen). Oxygen is black with a white top and nitrous oxide is blue.

Safety features of dedicated nitrous oxide delivery units Current machines have several design features that ensure nitrous oxide cannot be delivered at the expense of oxygen. They include: • Nitrous oxide cut-out – if the oxygen runs out, the nitrous oxide is automatically shut off and the patient will breathe room air • Minimum concentration of oxygen deliverable is 30 % • If the gas delivery from the common gas outlet is insufficient then air will be allowed into the system through the ‘air entrainment valve’ • Pin index and colour coding of cylinder attachments and tubing • Air entrainment valve allows room air entry if demand outstrips supply

SCAVENGING

There are two types – passive and active

Passive • Open windows and doors • Fans • Place expiratory limb out of a window

Passive scavenging is no longer recommended for use with patients in a dental environment.

Active (at 45 l/m) • Dedicated built-in systems • Off-the-shelf systems requiring minor installation procedure • Tubing systems that plug into the surgery’s wet-line slow suction system

CLINICAL TECHNIQUE

Pre-sedation equipment checks This should be done before the patient enters the surgery: • Dental chair and equipment working properly • ‘In use’ and ‘spare full’ gas bottles correctly attached • Fail-safe oxygen cut out system • Reservoir bag, tubing and nasal hoods are intact and connected properly • Scavenging/venting system is working and switched on • Emergency equipment and drugs • Other equipment that may be needed – e.g. radiography equipment

Pre-sedation assessment Compliance with pre-sedation instructions and procedures is the same as for any sedation episode. • Dental and sedation history • General medical history and ASA status • Co-operation, social history and circumstances • Blood pressure (adults) • Available and appropriate escort – see earlier note • Specific written, informed consent • Pre-sedation literature • Patient is not starved • Correct nasal hood size

Procedure for inhalation sedation (first time) • Set machine mixture dial to 100% oxygen • Set flow rate dial to between 5 and 8 litres/min for adults or children (average 6l/min) • Patient is reclined in dental chair • Pass nasal hood and tubing passed over head and give to patient to place on own nose • Help patient to adjust nasal hood for comfort. Ensure good seal. Adjust the position of the tubes behind the head for comfort and seal • Ask patient to take some deep breaths and check reservoir bag is moving properly and filling adequately. If not, check for leaks and adjust flow rate accordingly • Check that the patient is comfortable and reassure. Discourage mouth-breathing (this will also reduce pollution) • Mixture dial is then turned to 90% oxygen (10% nitrous oxide will be introduced)

• Inform patient that they may start to feel symptoms of sedation: § Tingling of hands/feet/around mouth/lips (paraesthesia) § Visual and auditory changes § Feelings of lightness or heaviness § Feelings of temperature change (usually warmth) § Floating sensations/light-headedness • Be positive, calming and reassuring • Verbally reinforce slow, calm deep breathing through the nose. Avoid the patient talking too much as it lessens the sedative effect. Use ‘closed questions’ with simple yes or no answers • After one minute adjust the mixture dial to 80% oxygen (20% nitrous oxide will be introduced) • Wait for one minute • Introduce further increments of 5% nitrous oxide at one-minute intervals until the desired effect is reached • Concentrations between 20 and 50% are usual for adults • Continually monitor the patient – check: § Level of consciousness § Demeanour/actions/responses § Skin colour – 10% of patients vasodilate and may feel warm and sweat a little § Airway patency § Breathing rate and depth – as the patient relaxes their breathing and depth rates will change. Match the machine’s flow rate to the patient § Mouth opening on request

Signs of sedation Nitrous oxide at this concentration may be more anxiolytic than sedative. The patient may appear quite alert and responsive but will be relaxed and accept treatment. • Acceptance of treatment – reduction of fear and anxiety • Reduced body and facial tension – general ‘detachment’ • Slowed responses – reduced frequency of blinking • Speech and voice changes • Mood change – laughing/giggling/daydreaming • Reduced pulse and breathing rates

Signs of over-sedation Maintenance of mouth opening is important. If the patient is unable to do this, they may be too deeply sedated. • Muscle rigidity and mouth closure • Disorientation and apprehension – increasing anxiety • Irritability and hallucinations • Nausea (vomiting is rare) • Emotional outbursts and crying • Unresponsiveness

Dental treatment Introduce items of treatment slowly and progress to the next if accepted. Start with topical anaesthetic and if patient accepts local, move on to treatment. Under normal circumstances, a mouth prop is not used for inhalation sedation but may be necessary in exceptional circumstances when a mouth-open posture cannot be maintained normally. In these instances, monitoring for over-sedation should be rigorous.

Recovery and discharge • To avoid diffusion hypoxia, give minimum of 2 minutes of 100% oxygen prior to removal of nasal hood by turning the mixture dial to 100% • Praise and encourage the patient at this time complementing them on their acceptance of treatment • Remove the nasal hood • Slowly return the patient to the upright position to guard against postural hypotension by sitting upright too quickly • Transfer to recovery area when ready • Test for alertness and orientation prior to leaving premises • Standard written and verbal post-sedation instructions to patient and escort – no driving, operating machinery, contact sports etc • Routine dental warnings – e.g. LA, post extraction etc

Subsequent sedation visits • For nitrous oxide ranges between 30 and 50%, the standard routine given above will be adequate • For sedation below 20% nitrous oxide use 5% increment from the outset – young children may sedate at quite low levels • For patients requiring high concentrations (55 - 70%) give the first four increments in 10% stages one minute apart then continue with 5% increments to the desired level

Nitrous oxide sedation as an adjunct to other techniques Nitrous oxide can be used to relax needle-phobic patients prior to venepuncture for intravenous sedation or local anaesthetics. Once this has been achieved the flow dial is returned to 100% oxygen for two minutes and the inhalation sedation can be stopped (or left on as the patient wishes).

CONCLUSION

Sedation with nitrous oxide is a useful technique for the mild to moderately anxious patient and avoids the need for cannulation. It requires moderately expensive equipment and effective semi-hypnotic reassurance from the dental team.

7 Monitoring

AIM OF MONITORING

To maintain a continuous observation and evaluation of the patient’s physiological and psychological status, together with the response to any changes to the patient management. This may be achieved by clinical monitoring alone using principally observation, sound and feel, or in combination with the aid of electro-mechanical monitoring devices designed to measure specific functions.

A very high proportion of critical events are preventable and can be attributed to lack of vigilance, or proper understanding and evaluation of the patient’s condition. A comprehensive pre-operative medical history is mandatory in preventing a critical incident by paying special attention to the patient’s appropriate vital signs.

During treatment under sedation, the monitoring of the level of consciousness is achieved by talking to the patient and assessing their response. This is used as feedback to determine the correct end point during induction. The patient should always be able to respond to their normal methods of communication, which is usually verbal command.

The aim in monitoring a patient, whether sedated or not, is to increase the patient’s safety during the dental procedure. It should commence from the initial contact and continue to the discharge of the patient.

The six vital signs 1. Heart rate, rhythm, and character (pulse) 2. Blood pressure 3. Respiration 4. Temperature 5. Height 6. Weight

Patient’s demeanour and levels of anxiety should be included when considering monitoring for sedation.

PRE-OPERATIVE MONITORING

The pre-operative monitoring of the appropriate vital signs, together with anxiety levels, should form part of the initial assessment of the patient. This is because realistic resting levels of their vital signs are better achieved when the patient is less stressed at the assessment appointment. It also helps to choose the most appropriate form of sedation and dental treatment indicated for the patient. The appropriate pre-operative levels should be noted and form part of the patient’s contemporaneous records.

RESPIRATION

This is the most important of the vital signs to monitor as it is depression of respiratory function which leads to cardiac dysfunction. Early recognition and correction of respiratory inadequacy will prevent a more serious problem developing.

Adequate respiratory exchange can be monitored by:

1. Observing respiratory rate – 12-16 breaths per minute. Rapid breathing indicates anxiety or pain. Reduced breathing can result from an overdose or too rapid administration of a sedative drug.

2. Observing normal chest movements. Movement is not always a guarantee of respiratory exchange. Chest and diaphragm movement indicates that the patient is making the mechanical movements, but the airway may be blocked by the tongue or foreign material preventing respiratory exchange. A see-saw movement of the chest and abdomen, together with a tracheal tug and no breath sounds indicates total obstruction.

3. Listening to breath sounds. • Normal breathing at rest is silent. Breath sounds result from a partial obstruction of the airway • Snoring is an upper airway obstruction as a result of the soft palate and tongue relaxing and falling back to partially occlude the oropharynx. This is best corrected by lifting the chin which pulls the tongue forward • Gurgling, indicating that fluid from the mouth or vomit has accumulated in the oropharynx. This can be cleared by good quality suction to prevent inhalation • Crackling, caused by secretions accumulating in the upper bronchial tree. The patient has difficulty with removing the secretions by coughing. This may be noted in the later stages of a cold or flu. It is one of the indicators of COPD together with the use of accessory respiratory muscles in the neck and shoulders and a possible change in the colour of the patient • Wheezing is a lower airway obstruction caused by bronchospasm. It is treated by the use of a bronchodilator such as salbutomol inhalation if the patient is conscious or IM/IV if unconscious • Crowing / stridor. This is caused by a partial laryngospasm resulting in the passage of small quantities of air inhaled with effort past the vocal chords and can lead to complete obstruction. It is managed by suction and mechanical removal together with positive pressure oxygen ventilation

4. Observing colour: It is particularly important to note any change in colour of the patient. • Pale / white – anaemia or about to faint • Red – raised blood pressure or “pink puffer” in COPD • Blue – hypoxia • Grey – myocardial infarct

5. Observing movement of the reservoir bag if inhalation sedation or oxygen is administered.

CARDIOVASCULAR MONITORING

Pulse Pulse is detected where an artery is adjacent to a firm structure and is palpated by the fleshy tips of 1 or 2 fingers. Beats are counted for 15 or 20 seconds, and multiplied up to give beats per minute (bpm). Rate Normal 70 – 80 bpm Tachycardia > 100bpm Bradycardia < 50bpm

Rhythm Regular or irregular Note types of irregularity

Volume Normal Bounding Raised BP Feeble Low BP -? Faint

Sites of pulse • Radial – Lateral wrist • Brachial – Medial ACF • Carotid – Groove between sternomastoid and trachea • Facial – Lower border of mandible • Temporal – Anterior tragus of ear

Blood Pressure (BP) BP is measured using a stethoscope and a sphygmomanometer. Readings are in millimetres of mercury (mmHg) derived from the old mercury manometers that were originally used to measure BP.

Sounds are only heard when there is turbulence created by the blood being forced past the obstruction of the inflated cuff. The cuff is inflated to occlude the artery and then slowly let down.

Systole is the maximum pressure created by the contraction of the heart and is noted as the first sound is heard in the stethoscope, when the heart is just able to exceed the cuff pressure.

Diastole is noted when the sound disappears or becomes muted and the flow in the artery is unimpeded and returns to laminar flow. This is the resting pressure of the heart in between contractions.

Blood pressure is recorded as the systolic pressure over diastolic pressure. Normal adult blood pressure is 120mm / 80mm Hg.

Hypertension (raised BP) Systolic pressure > 180mm Hg Diastolic pressure > 105mm Hg

Hypotension (low BP) Systolic pressure < 90mm Hg Diastolic pressure < 40mm Hg

Laminar flow pushing past Turbulent Flow Laminar flow No Flow pushing past cuff No Sound No Sound obstruction creates sound

Patients that present with abnormal BPs should be referred to their GP for investigation prior to treatment.

Automatic battery-operated devices for measuring BP are becoming more popular. These are easier to use than the mechanical method and produce more consistent results when used by inexperienced staff. The devices work by sensing the pressure waves generated whilst the pulse passes along the cuff.

Pulse oximeter This is a non-invasive device which measures the oxygen saturation of arterial blood together with the characters of the pulse. It accurately reflects the patient’s cardio-pulmonary efficiency and can be set with alarms to warn the operator if the readings vary outside normal limits. It is mandatory to monitor all patients with this device when they are treated under IV or high-dose oral/intranasal sedation.

Method of operation Two light emitting diodes, one in the red spectrum of 680nm and one in the infrared spectrum of 940nm, transmit light across the patient’s tissue, usually across a digit using a simple probe with a sensor. The amount of light absorbed across the tissue is measured in both the wavelengths at 50 cycles per second. Only the variable signal caused by the absorption of arterial pulse flow is noted. By this method, variable anatomical features of patients are negated, such as the width of the finger or the pigment of the skin, and only the common factor of arterial pulsatile flow is recorded.

A complex algorithm within the machine calculates the red to blue ratio which results in the amounts of oxygenated (red) to reduced haemoglobin (blue) that are present in the arterial blood. The results are calculated over a period of 8 – 10 beats and averaged. This gives an accuracy of between 1 and 3%. The results are therefore always in the past and represent the patient’s state about 10 seconds previously.

Display The results are displayed on the machine as the % oxygen saturation (Sats) of the patient’s haemoglobin and together with the pulse rate, are displayed as figures on the face of the machine. These are accompanied by a beeping sound in rhythm with the pulse, the tone of which goes up or down to indicate the varying saturation levels of the patient’s blood.

Some machines show a graphical representation of the patient’s pulse, indicating rhythm and volume, and as such equate to monitoring the pulse by palpation. This allows the sedation team to monitor the patient both aurally and by visual reference to the display.

Alarms The machines have alarms built into the system to indicate if there are problems with recording the signal or if the patient’s values are falling outside normal levels. These alarms can be set by the operator. Low oxygen saturation <90% High pulse rate >150bpm Low pulse rate <40bpm Probe off the finger and no signal

Capnography Sampled exhaled gas or transcutaneous monitoring of carbon dioxide (capnography) instantaneously measures expired carbon dioxide and warns of hypoxaemia by up to 240 seconds in advance of pulse oximetry. Capnography may be indicated for some ‘at risk’ ASA III/IV dental patients, particularly those receiving supplemental oxygen and/or where ventilation cannot be directly observed. However, despite the growing pressure for it to be used universally in the UK, until the results of dentistry-specific research is available, its routine use for ASA I and II dental patients lacks high-quality scientific validation and cannot be recommended. Capnography is described as a ‘Developmental Standard’ by the AoMRC (2013).

PSYCHOACTIVE MONITORING

This is used to determine the patient’s general demeanour and level of anxiety. It is carried out at the initial assessment visit and can be aided by asking the patient to complete a series of questions such as ‘The Modified Dental Anxiety Scale’ or the ‘Venham Scale of Anxiety’. Whilst these may be of use, observation of the patient and the use of clinical experience is the best method of assessing the patient prior to treatment.

CONCLUSION Effective monitoring by the dental team is crucial for the safety of the patient treated with conscious sedation. Equipment is required but clinical monitoring is even more important and forms part of the role of the dental nurse.

8 Management of Sedation Related Complications

Introduction Serious complications are rare when using a single drug properly administered as described in this handbook. The risk of problems is also reduced by careful planning, updating the medical history and by the whole dental team keeping up to date. Minor problems do occur more frequently, but most can be dealt with by a well organised dental team.

SERIOUS COMPLICATIONS

Respiratory depression This can be caused by over-sedation due to either too rapid administration of midazolam or an overdose. It is recognised by the pulse oximeter alarm and if saturation drops significantly, the patient turning blue. All treatment should stop and the patient instructed to take deep breaths. If they fail to respond to this, the airway should be opened (head tilt/chin lift or jaw thrust) and high flow oxygen administered. This should not be via a nasal cannula but by positive pressure ventilation using a self-inflating bag. If this does not improve the situation, flumazenil 500mcgs should be administered. It is rare to have to take steps further than reminding the patient to breathe and opening up the airway.

Respiratory depression can also occur due to obstruction of the airway. This can be due to blockage by water and debris in the oropharynx or downward pressure on the mandible during extraction of lower teeth. Here the solutions are better suction and supporting the mandible during the extraction.

Allergy Allergy to midazolam is very rare. If a patient reports allergy to the benzodiazepines, then further investigation by a medical allergy specialist should be carried out before assuming that general anaesthesia is indicated. Allergy to latex does not preclude the use of IV or inhalational sedation as neither the cannulae nor mask contain latex.

If an allergic reaction to midazolam does occur, flumazenil must not be administered.

Cardiac arrest This is fortunately very rare and is more likely to be due to underlying cardiovascular disease than sedation.

MINOR COMPLICATIONS

Hypotension All sedative drugs cause a fall in blood pressure. This does not cause any particular problems during sedation but at the end of treatment, patients should be brought slowly back to the upright position.

Cannulation The most common problem is failure to find a vein. With experience this becomes less frequent. Some patients are very difficult – be wary of overweight patients or those who have had numerous cannulations in the past. It is worth taking time to find a good site and consider asking a colleague for help. Failed cannulation sites should have pressure applied to minimise bruising.

Hiccups This is usually associated with too rapid injection of midazolam or over-sedation. Unfortunately, midazolam induced hiccups may last longer than usual ones, making dentistry difficult. The only management is to try the usual remedies or wait for them to pass. When treating this patient in the future, midazolam should be given very slowly.

Paradoxical effects There are some people who become more difficult to manage and exhibit uncontrolled behaviour and disinhibition such as movement, and are noisy and often tearful. These tend to be younger people but there is no way of predicting who is going to react in this way. Inexperienced sedationists often think that they have under-sedated and administer more and more drug which only makes the patient more difficult to manage. The only course of action is to stop treatm,ent and reconsider, perhaps considering an alternative technique, general anaesthesia or another attempt with sedation on another day. A careful explanation must be given to the escort and to the patient. Prior warning to parents of adolescent patients that disinhibition may occur can often save embarrassment later.

Prolonged recovery There is no way of predicting which patients will be affected. Most people should show signs of recovery an hour after the last increment of midazolam. If not, then reversal with flumazenil may be indicated. For future appointments it would be sensible not to book the last appointment of the day.

Nausea and vomiting This is uncommon with IV sedation with midazolam, infrequent with nitrous oxide, but a common side effect of opioids. Nausea with inhalational sedation usually indicates over-sedation and the dose should be reduced. When dealing with a patient who feels nauseous, it is better to allow them to recover slowly in the dental chair. Occasionally, anti-emetics may be required.

Under- and over-sedation This usually occurs with the less experienced sedationist who initially under -edates patients, then as confidence grows over-sedates, and finally after more experience manages to judge the correct amount of drug. In the case of under-sedation, ‘topping up’ with further increments is very tempting but this can lead to over-sedation and an increased recovery time. Over-sedation is indicated by an unresponsive patient. In this case, the sedation can be lightened by administering a small amount of flumazenil (100mcg). This should improve consciousness and make it possible to carry on with treatment.

Adjusting the level of sedation is easy with nitrous oxide and involves simply adjusting the concentration. It is better not to allow the patient to remove the mask.

Sexual fantasies This is a recognised complication of the benzodiazepines particularly associated with over- sedation and highlights the importance of chaperoning. No one person should be left alone in a room with a sedated patient. This applies to both the dentist and the dental nurse. It does not matter what combination of genders is involved. Always having another person present will reduce the risk that a patient complaint will be upheld. Another option is to have the escort present throughout treatment.

MANAGEMENT OF CARDIAC ARREST

Please refer to Resus Council (UK) for latest guidance: https://www.resus.org.uk/resuscitation-guidelines/adult-basic-life-support- and-automated-external-defibrillation/#blsaed

9 Paediatric Sedation Techniques

Introduction

Many children perceive dental treatment to be stressful. The 2013 Child Dental Health Survey of self-reported anxiety across 12-15-year-olds in the U.K., found that 14% of 12-year-olds and 10% of 15-year-olds were classified as having extreme dental anxiety. A fifth of parents of 5-8-year- olds reported that their child had moderate to extreme anxiety. A visit to the dentist may include stress invoking components such as meeting new adults and authority figures, strange sounds, smells, sensations and tastes, having to lie down, holding one’s mouth open, discomfort and pain. Children with oral or dental pain are often frightened and uncooperative. This fear is often exacerbated by parental anxiety, separation anxiety and the actual or anticipated discomfort about the dental procedure itself. Children with behaviour management problems demand considerable time, patience and expertise. Not all children will be managed solely by the use of behaviour management techniques and sometimes a combination of behaviour management techniques and pharmacological sedation may be necessary. When behavioural management and therapies alone are insufficient for completion of treatment, sedation can reduce the need for a general anaesthetic.

Aim of sedation

To reduce anxiety and improve cooperation for dental treatment.

Objectives

• Provide high quality dental care • Manage disruptive behaviour • Quickly return the patient to a physiological state • To produce a positive psychological response to dental treatment

Paediatric sedation assessment

Assessment for paediatric sedation will include:

• Assessment of dental need • Assessment of patient cooperation and behaviour • Use of anxiety questionnaires, e.g. MCDAS • Assessment of parental cooperation and involvement • Preoperative medical assessment • Alternative treatment plans • Training and experience of the sedationist, dentist and staff • Consent • Provision of pre-operative instructions and information

For children under 12 years of age, behaviour management and inhalation sedation with nitrous oxide / oxygen is the sedation technique of choice for use by an appropriately trained dental team. The chronological age of the child, however is less important than the physical and psychological age of the child. The Resuscitation Council (UK) describes a child as between one-year-old and puberty. As puberty may be early or late, age should be considered in the context of physical and psychological maturity when assessing a patient for sedation.

If more advanced techniques are required, then referral to a facility equivalent to an NHS Acute Trust in England, with a team with skills equivalent to those expected of a specialist / consultant in paediatric dentistry and a consultant in anaesthesia competent in sedation for dentistry, would be necessary.

For a young person aged 12-16 years having dental treatment, the standard sedation techniques that can be used by an appropriately trained dental practitioner include: behaviour management, inhalation sedation, and intravenous midazolam sedation. If more advanced techniques are required, then a referral should be made to a facility equivalent to an NHS Acute Trust in England for assessment and treatment by a team with skills equivalent to those expected of a specialist / consultant in paediatric dentistry and a consultant in anaesthesia competent in sedation for dentistry.

Techniques used for treatment of paediatric patients may include:

• Inhalation sedation (IS) (or Relative Analgesia – RA) with nitrous oxide and oxygen • Intravenous sedation with midazolam • Intranasal sedation with midazolam • Oral sedation with midazolam • Oral or intranasal sedation combined with a titrated dose of nitrous oxide • Oral or intranasal sedation followed by intravenous sedation • Inhalation sedation with nitrous oxide and sevoflurane • Nitrous oxide and sevoflurane inhalation sedation followed by intravenous sedation • Intravenous sedation with propofol

No single sedation technique will be effective in all patients – the greater the range of techniques available to the practitioner, the greater the likelihood of a successful outcome.

The goal is to use the most controllable and least profound technique that is capable of providing the desired goal. Wherever possible, titration of drugs with a large margin of safety should be employed i.e. inhalation sedation or intravenous midazolam sedation – this eliminates the need for ‘guessing’ the most appropriate dose for the child. Whilst oral and intranasal sedation with midazolam are considered a standard technique for young people aged 12-16, their use has limited scope.

Inhalation sedation with nitrous oxide and oxygen

This remains the safest and most widely used sedation technique in children and young people who are mildly anxious and who are cooperative. The advantages of the technique are the same as with adults; children become very susceptible to guided imagery and can become very suggestible while under the influence of the gas. Nitrous oxide is titrated to response (as per Chapter 6), with concentrations between 25-35% nitrous oxide commonly producing the desired level of sedation.

Disadvantages: • The lack of potency may render the technique ineffective in the management of the more apprehensive and uncooperative (younger) patient • Requires a level of cooperation and maturity to continually breathe in and out through the nose during treatment • Some children object to the placement of the nasal mask • Children often have blocked noses and enlarged adenoids and find it difficult to breathe through their noses while their mouths remain open for treatment • Reduced access for treatment of the upper anterior teeth

Intravenous sedation with midazolam

Traditionally, the intravenous route has not been used in paediatric dental sedation as access to GA facilities was readily available prior to December 2001. No studies were conducted, and guidelines reported that IV sedation in children was contraindicated, as early attempts to sedate some children with midazolam IV precipitated a ‘paradoxical’ reaction and the assumption was made that the effects on children were unpredictable. Guidance also said that the therapeutic margin in children was narrow, but there was no evidence base for this assertion. Evidence from other studies where transmucosal midazolam has been used contradicts these statements.

Prior to cannulation, it is good practice to use some form of topical anaesthetic on the cannulation site. Midazolam may be titrated in small increments, i.e. 1mg loading dose followed by 60-second increments of 0.5mg until the patient is ready for treatment. (Dose range approx. 0.08-0.12mg/kg.) Midazolam produces anterograde amnesia.

Disadvantages: • Paradoxical effect and disinhibition • Requires cannulation • Longer recovery period needed than for inhalation sedation • Requires the help of an escort e.g. to help relay any information about post-operative care to the patient

Other techniques

Intranasal sedation Intranasal midazolam is administered in a syringe connected to an intranasal mucosal atomisation device (MAD). Research was carried out using 10mg/2ml concentrated midazolam at a dose of 0.2mg/kg (maximum dose 10mg). It was relatively easy to administer with half the volume up each nostril with the child encouraged to sniff up the liquid; however there were some difficulties due to the quantity of liquid necessary. Children experienced coughing, sneezing and spluttering as the liquid dripped down the back of their throat. Since then, a more highly concentrated 40mg/ml with 20mg/ml lignocaine has been developed. Midazolam is directly absorbed through the blood vessel rich nasal mucosa resulting in a reliable and predictable onset of action 5-10 minutes after administration. Intranasal midazolam has a 55% bioavailability. Sedation duration may last 15-20 minutes. Side-effects are minimal,except for the burning, stinging sensation on the nasal mucosa.

Midazolam oral sedation Oral sedation is a valuable technique when used as a sedation technique on its own or when prescribed as a pre-medication prior to using another sedation technique. Children have most likely already had experience of taking oral medications such as analgesics or antibiotics via this route. There is no need for a mask, however, after administration of oral sedatives, venous access should be obtained or carefully considered and justified if not obtained. Intravenous access would ensure that there is readily available access should flumazenil become necessary. The difficulty of this technique lies in the dose determination of the drug/drugs which are to be administered. There are various aspects that need to be taken into consideration when prescribing an oral dose: • Age and weight of the child • Anxiety level of the child • Level of sedation or pre-medication (target zone) • Activity of child – calm or hyperactive • Time of day – higher doses in morning vs afternoon • Cooperation of the parent / guardian

Disadvantages of the oral route: • Often drugs have a bad taste which needs to be disguised in a sweet-tasting drink e.g. blackcurrant juice or orange juice. In spite of this, children often spit it out. • Oral drugs have unpredictable absorption • Long latent period and onset of working • Duration of action could be prolonged • Cannulation must be considered • As oral drugs are filtered through the portal system, higher doses need to be administered. Bioavailability is 15-30%

• Some children become disinhibited. This ‘paradoxical’ reaction occurs with midazolam. Children can become violent, cry or scream and become uncontrollable. Children may kick and fight with parents or staff and use inappropriate language. Treatment may be impossible and may need to be abandoned • These drugs are often used ‘off licence’ – they are licensed for intravenous use but can be used orally

A dose of 0.3-0.5mg/kg (maximum dose 20mg) in squash is taken 20-30 minutes prior to the procedure. This causes anxiolysis, muscle relaxation, amnesia and eventually sedation. Patients need to be closely monitored clinically and with pulse oximetry. Children have a relatively high basal metabolic rate and the duration of action can be quite short. Use the 5mg/ml oral solution to reduce the quantity of liquid that must be swallowed. Side-effects include: reduced respiratory drive, hiccups and the paradoxical effect. This technique may occasionally be combined with inhalation sedation as an advanced technique.

Advanced techniques

This is an emerging field that requires further investigation to build a body of evidence in the area. Although not routinely used, techniques used within the UK include or have included:

Ketamine oral sedation Creates dissociation sedation with an analgesic component. Ketamine sedation is an area in which there is currently limited evidence. It has however been used successfully with and without midazolam (the latter being used to combat the paradoxical effect). 2-3mg/kg co-administered with 0.3mg/kg midazolam to combat the paradoxical effect, reduces the ‘emergence phenomenon’ and provides significant analgesia which helps with pain associated with intraoral injections and with cannulation. Side-effects include: nausea and vomiting in 5-10% of cases, blurred vision and hallucinations in 1% of children.

Advanced intravenous sedation Opioids: Fentanil and alfentanil have been used in combination with midazolam for surgical procedures. The rationale is to provide added sedation as well as analgesic benefits (we can then administer less midazolam). The potentially fatal side-effect, especially in children, is that severe respiratory depression can be produced resulting in respiratory arrest and asystole if not recognised early enough. Children need to be monitored very closely and early desaturation needs to be corrected instantly. Opioids should not be administered to children by anyone other than a consultant anaesthetist working within a team who are trained and experienced in providing paediatric sedation.

Ketamine: Ketamine in combination with titrated midazolam creates a dissociation-sedation. Analgesia is also obtained. There is bronchodilation and respiratory and cardiovascular stimulation in sedative doses. Side-effects include excessive salivation, but this is rare. Recovery is rapid- within 15-20 minutes. If children have large tonsils and a lot of water drips down the back of the pharynx, i.e. inadequate aspiration, the larynx could be stimulated, resulting in a potential emergency –laryngospasm. This fortunately happens rarely, but advanced airway skills in children are mandatory when using this drug. Again, the emphasis is on teams having the necessary skills, expertise and experience in the management of this group of sedated patients. Hallucinations in this group are rare, especially so when used in conjunction with a benzodiazepine.

Propofol: Propofol has been used for short procedures and also for long sedation procedures with the aid of an infusion pump. Most work is done in hospital at the moment. Advanced airway management skills are mandatory and this cannot be regarded as an operator-sedationist technique.

Advanced inhalation sedation: Sevoflurane + nitrous oxide and oxygen The addition of 0.1-0.3% sevoflurane, an anaesthetic volatile agent, increases the cooperation of children and allows dental treatment to be completed more successfully. This appeared to be a very safe technique and much more effective than nitrous oxide / oxygen inhalation sedation alone.

CONCLUSION

Sedation can help to facilitate comfortable dental experiences for children and young people. This is key, as the impressions about dentistry gained as a paediatric patient will shape a patient’s viewpoint on dental care for life. Sedation for children requires careful assessment and preparation of the child and parent / guardian as part of the treatment planning process. Generally, inhalational sedation with nitrous oxide/oxygen is suitable for most children; however, intravenous midazolam sedation for older children can also help improve cooperation for older children who may require further anxiolysis. Other techniques however may be useful for certain patients but require a suitable environment and teams. Whichever technique is used, team members must have appropriate training and experience. Advanced paediatric sedation is a developing field which may facilitate care for patients for whom the standard techniques are less suitable.

10 Alternative Sedation Techniques

Introduction Simple dental sedation techniques (e.g. intravenous midazolam and inhaled nitrous oxide/oxygen) are appropriate, safe and successful for the majority of fit and cooperative patients. However, it is important to recognise that some individuals may be better managed using alternative (sometimes called ‘advanced’) sedation techniques. These techniques are only suitable for use by practitioners with appropriate training and experience working in an appropriate environment.

FAILED SEDATION

Recognising failed sedation Sedation techniques are not always successful. Failure may occur for a variety of reasons relating to the patient, the operator and/or the technique chosen. The more challenging the patient and the more difficult the sedation and dental procedure, the greater the likelihood of failure. No sedationist achieves one hundred per cent success with all patient groups. The most common causes of failure include: • Incorrect patient assessment • Unrealistic expectations (patient or dentist) • Failure to accept that sedation is not the same as general anaesthesia • Poor dental treatment planning • Technique failure (eg. venepuncture, LA, psychological support) • Missing the IV sedation ‘window’ (e.g. hesitant dentistry) • ‘Bad sedation day’

Managing failed sedation As soon as it becomes clear that the chosen sedation technique is not going to allow the intended treatment to be completed to the satisfaction of both patient and dentist, it is advisable to stop and carry out whatever temporary measures are indicated so the patient can be discharged comfortably and safely. Continuing with treatment on a protesting patient is doomed to failure and likely to produce dissatisfaction and even complaints. Subsequent treatment may be made more difficult as the patient will have lost confidence.

The disappointment of failure must be overcome by adopting an honest, flexible and positive approach. If the patient is still sedated or upset, it is probably better to arrange another appointment for future treatment planning. When discussing this with the patient (and perhaps the escort), it is important to be reassuring whilst not promising the impossible. If there are appropriate facilities and expertise in the practice, alternative sedation techniques may be considered and the possible advantages outlined. If other techniques cannot be offered or it is clear that the patient does not wish to return, a referral should be made for treatment under alternative sedation techniques or even general anaesthesia.

ALTERNATIVE TECHNIQUES

Alternative (advanced) techniques include: • Intravenous midazolam preceded by an opioid • Intravenous propofol by infusion • Intravenous sedation by patient-controlled infusion • Inhalation sedation with sevoflurane • Oral sedation with benzodiazepines (standard technique subject to experience) • Intranasal sedation using midazolam (standard technique subject to experience)

Intravenous midazolam preceded by an opioid Individuals who are not adequately sedated using intravenous midazolam alone, may sometimes be successfully managed by administering a small bolus of an opioid drug prior to titrating the midazolam. Whilst it is usually preferable to use a single drug, using a combination technique may avoid the need for general anaesthesia. The opioid selected should ideally have a shorter duration of action than midazolam so as to avoid prolonged recovery. Pethidine, fentanil, alfentanil and nalbuphine have all been used (nalbuphine has recently been withdrawn and is no longer available).

Technique: • Slowly administer an appropriate dose of the chosen opioid • Wait for one minute • Titrate midazolam in appropriate increments • Note that the total dose of midazolam will probably be considerably less than that required if no opioid is given.

All opioid drugs have the potential to cause dangerous respiratory depression necessitating prompt and effective management from the dental team. Nausea and vomiting is a common side-effect of these drugs.

Intravenous propofol by operator-controlled infusion Propofol is a potent short-acting intravenous anaesthetic agent. In sub-anaesthetic concentrations it is a reliable and safe drug for intravenous sedation with a considerably shorter distribution half- life than midazolam. By comparison with midazolam, recovery is rapid and patients report feeling 'clear-headed' more quickly. Amnesia is often less profound. Propofol confers a greater degree of anxiolysis than sedation and patients appear less 'knocked out' than with midazolam. When administered by continuous infusion, propofol is more controllable than titrated midazolam and the depth of sedation may be varied during the procedure. It is particularly useful both for very short cases and for lengthy procedures. There are few contraindications to propofol but it should be avoided if there is a known or suspected allergy to any of its components or for patients with epilepsy.

Propofol infusion techniques are not suitable for use by an operator-sedationist. The technique may only be used by a second practitioner who has received specific training and is experienced. An example of a method for the administration of propofol sedation is: • 30mg (3ml) of propofol is given by slow manual injection • An infusion is then started using a syringe pump at an initial rate of 300mg (30ml) per hour • Sedation usually occurs within 1-2 minutes • The infusion rate may need to be adjusted during long procedures

Particular care is needed with procedures lasting longer than thirty minutes, in order to avoid too deep a level of sedation. Careful clinical monitoring and pulse oximetry is mandatory. Although respiratory depression may occur, it appears to be less marked than is the case with midazolam. As with all dental sedation techniques, the use of appropriate local analgesia is essential. The procedure for recovery is similar to that for midazolam. The criteria for discharge and instructions for after-care suggested for midazolam should be observed.

Intravenous sedation by patient-controlled infusion Both midazolam and propofol have been used successfully in Patient-Controlled Sedation (PCS) systems. An infusion pump with a demand system allows the patient to control the depth of sedation. Over-dosage is prevented by a time-based ‘lockout’. In addition to making the patient feel more ‘in control’, PCS may optimise the level of sedation and thus reduce the incidence of both under- and over-sedation.

Oral sedation with benzodiazepines Oral benzodiazepines may be useful where the patient is anxious about venepuncture or where cannulation is impossible due to lack of cooperation; for example, in the case of patients with certain physical or learning disabilities.

The sedation produced may sometimes be sufficient for simple dental procedures to be carried out. Alternatively, it may be employed to facilitate cannulation for intravenous sedation. The most commonly used drugs are temazepam (adult dose: 30 mg) or midazolam (adult dose: 20 mg). Temazepam is best administered as a proprietary oral syrup which is reasonably palatable, rather than as tablets, which may be difficult to swallow. The time to peak effect is variable. Typically, adequate sedation usually occurs approximately 30-45 minutes following ingestion of the drug. Sedation must be administered in the dental surgery under supervision of the dentist. Temazepam 30mg may be expected to produce a similar depth of sedation as is usually achieved with a correctly titrated dose of intravenous midazolam.

Oral midazolam is available in syrup form (Amsed) at a strength of 2.5mg/ml. For most adults, 20mg is recommended (8ml) and may be administered. The intravenous preparation (either 10mg/2ml or 10mg/5ml) could also be used mixed with fruit juice to improve its palatability. The time to peak effect is less variable than with temazepam. Using midazolam, sedation usually occurs approximately 10-20 minutes following ingestion of the drug. As with temazepam, sedation must be administered in the dental surgery under supervision of the dentist.

The management of patients who have received oral temazepam or midazolam is very similar to that for those who have had intravenous midazolam. As the depth of sedation is similar, clinical monitoring and the use of a pulse oximeter are mandatory and the discharge criteria are identical. Although midazolam does not have a UK product licence for oral administration, this does not mean that it cannot be used for conscious sedation in dentistry. The oral route is commonly used in other areas of sedation practice, for example, accident and emergency medicine. There is also a large body of published evidence relating to its safety and efficacy.

It is important to appreciate that the apparent simplicity of oral sedation belies the potential for undesirable effects in addition to the desired sedative effect. In particular, the risk of respiratory depression is every bit as great with oral sedation as it is with intravenous midazolam. Once sedation is established, a cannula should be inserted in order to be able to administer flumazenil in the event of serious problems or to top up the midazolam if required.

Intranasal sedation using midazolam Midazolam may also be administered intranasally. As with oral administration, this application is currently unlicensed. In adults, 10mg of the 10mg/2ml concentration is usually sufficient and is surprisingly well tolerated by patients. Higher concentration preparations of 40mg/ml midazolam are available from some hospital pharmacies. Intranasal midazolam is rapidly absorbed through the nasal mucosa directly into the circulation and therefore the peak effect occurs sooner than with the oral route, with approximately 80% bioavailability. The use of a mucosal atomiser device enables efficient and effective delivery of the drug intranasally. Patient monitoring and discharge criteria are identical to those for intravenous sedation with midazolam. Cannulation should be carried out as soon as possible to enable the midazolam to be topped up if necessary or for reversal with flumazenil. This technique finds particular application in patients with disabilities who are unable to cooperate sufficiently for more conventional routes of administration to be successful. As with oral sedation, the potential for adverse effects must be considered carefully. With such fixed-dose techniques there is always a risk of unpredicted under- or over-sedation.

Inhalational sedation with sevoflurane Inhalational sedation using sevoflurane in oxygen (or a mixture of nitrous oxide and oxygen) is currently receiving research attention. Sevoflurane is a potent volatile anaesthetic agent with favourable blood gas solubility and a low MAC. Induction is rapid and the relatively high potency controlled by a suitably calibrated vaporiser. At present, sevoflurane sedation must be administered only by people trained in anaesthesia.

Possible reasons for referral for general anaesthesia are: • Some medically compromised patients (eg. severe asthma, proven allergy to all LA) • People with disabilities who cannot be managed with sedation • Paediatric patients (e.g. pre- or un-cooperative children, extensive treatment) • Failed sedation • Adult patients requiring extensive, long or unpleasant treatment

CONCLUSION

Intravenous sedation with midazolam is probably the most widely used conscious sedation technique, but knowledge of alternative drugs and routes of administration may occasionally be helpful. Generally speaking, the simplest technique is usually the most appropriate. There remain sound indications for the use of general anaesthesia in dentistry.

11 Sedation for Medically Compromised Patients

Sedation for patients with significant medical problems is usually best provided by appropriately trained and experienced sedation teams.

ASSESSING RISK

When assessing a patient’s suitability for dental treatment under conscious sedation it is important to consider: • The patient’s degree of anxiety • The nature of the dental treatment required (duration, frequency, complexity etc.) • The nature, severity and stability of the patient’s medical conditions

Classification of medical fitness The most commonly used system for the classification of medical risk is the American Society of Anesthesiologists (ASA) Physical Status Classification System. This system, developed in the 1960s, is designed to estimate the medical risk presented by a patient undergoing a surgical procedure. This system stratifies the patient’s risk:

ASA I • a ‘normal’, healthy patient who is well able to tolerate physiological stress • has little or no anxiety • is normotensive

ASA II • an extremely anxious patient • a patient at the extremes of age • pregnancy • obesity (body mass index > 30) • mild systemic disease e.g. exercise induced asthma

ASA III • severe disease, limiting the patient’s activities but not incapacitating, e.g. stable angina; type 1 diabetes • hypertension < 199/114 mmHg

ASA IV • incapacitating disease which is a constant threat to life, e.g. unstable angina • hypertension > 200/115 mmHg

ASA V • a patient with end-stage disease not expected to live > 24 hours • a patient who is diagnosed with brain stem death awaiting organ retrieval

It is important to remember that most medical conditions are not static in their severity and the ASA assessment must be revised at each visit/course of treatment.

INDICATIONS FOR SEDATION

Sedation may be considered for medically compromised patients who: • have dental anxiety • have medical conditions potentially aggravated by stress, e.g. angina, asthma, epilepsy • have involuntary movements which potentially compromise the quality of operative care • require an operative procedure for which local analgesia alone is inadvisable

Sedation and cardiovascular disease Cardiovascular disease is common in the UK population and the severity and nature of disease very variable. In many cardiovascular conditions, there is a high risk of exacerbation if myocardial oxygenation is inadequate.

Angina pectoris Angina pectoris is a clinical syndrome which occurs whenever there is an imbalance between myocardial oxygen supply and demand. Coronary atheroma is its most common cause. Stable angina (ASA 3) is characterised by central chest pain, discomfort or breathlessness that is precipitated by exertion and other forms of stress and is promptly relieved by rest.

When treating a patient with angina, the clinician aims to minimise physiological and emotional stress while maximising myocardial oxygenation.

Oral pre-medication may be helpful if the patient has high levels of anticipatory anxiety about their dental treatment. Inhalational sedation would provide good stress reduction, analgesia and oxygenation level. Intravenous sedation with supplemental oxygen could be considered for the very anxious patient.

Acute coronary syndrome This term encompasses unstable angina and myocardial infarction (ASA IV/V). It may present as a new phenomenon or against a background of stable angina. The symptoms are similar to those of stable angina though usually more severe and not relieved by rest.

After having a myocardial infarction (MI), a patient is at high risk of a second MI, especially within six months of the first. It is therefore advisable to postpone any routine dental treatment until > 6 months post-MI. The patient may then be suitable for treatment under conscious sedation using the same techniques as for the patient with stable angina.

Hypertension 90% of patients in the UK with hypertension have essential hypertension, i.e. no specific underlying systemic condition can be found. Disease severity and control varies greatly (ASA II – IV). Patients with a blood pressure of > 200/110 mmHg require urgent investigation and treatment, often involving hospital admission. The blood pressure of hypertensive patients responds poorly to stress and this should be remembered when providing dental treatment with or without sedation. Those taking antihypertensive medication are susceptible to postural hypotension and so patient positioning should reflect this.

Oral, inhalational and intravenous sedation are all suitable for patients with stable disease.

Sedation and respiratory disease Respiratory symptoms are the most common cause of presentation to a GMP. Asthma occurs in 10% of the UK population, chronic obstructive pulmonary disease affects 15% of smokers, while bronchial carcinoma is the most common fatal malignancy in the developed world.

Asthma Asthma is responsible for ~1500 deaths in the UK per year. The cardinal features of asthma are: • airflow limitation • airway hyper-responsiveness • airway inflammation It is not a uniform disease, but a dynamic one with many clinical patterns, most of which include risk of exacerbation by stress. It is therefore important to establish the severity and degree of disease control (ASA II – IV). NSAIDs and opioid analgesics should be avoided in asthmatic patients.

All forms of sedation will produce anxiolysis without airway irritation and are therefore suitable for patients with stable asthma.

Chronic obstructive pulmonary disease (COPD) This condition encompasses chronic bronchitis and emphysema and has a close association with smoking. Symptoms include cough, breathlessness, wheeze and sputum. The disease is usually slowly progressive (ASA II – IV), with 50% of those with severe breathlessness (ASA IV) having a life expectancy < 5 years. Patients with COPD rely on hypoxic drive, i.e. fall in arterial oxygen rather than rising carbon dioxide levels to drive respiration. There is therefore a theoretical risk involved with inhalational sedation (which provides supraphysiological oxygenation) but in practice it is probably the most appropriate form of sedation in this patient group.

Sedation and neurological disease Some 10% of the population consult their doctor each year with a neurological symptom, while neurological disorders account for 20% of acute admissions to hospital.

Epilepsy Epilepsy means a tendency to have seizures and is a symptom of brain disease. After a single seizure, there is a 40% risk of subsequent seizures. It affects 3% of the general population and 30% of those with a learning disability, the most common form being tonic/clonic seizures. Seizure trigger factors such as sleep deprivation, alcohol, stress, hypoxia and infection have been identified.

Oral, inhalational and intravenous sedation are suitable for patients with epilepsy though care should be taken in using propofol for patients with epilepsy (there is evidence that propofol can induce, as well as terminate, seizures). It may be sensible to use supplemental oxygen with intravenous sedation.

Involuntary movement disorders This group includes cerebral palsies, multiple sclerosis and Parkinson’s disease. The conditions themselves range in severity and may be associated with additional medical problems. Variable cognitive ability may preclude inhalational sedation in some patients with involuntary movement, as may affect physical ability to comply with wearing the nasal hood. Oral and intranasal sedation often facilitates cannulation where movement is severe. Oral and intravenous sedation often reduce involuntary movements but are not guaranteed to do so. Indeed, in some instances the movements may increase.

Myasthenia gravis Myasthenia gravis is an autoimmune disease involving destruction of the post-synaptic acetylcholine receptors. This leads to a progressive inability to sustain a maintained or repeated contraction of striated muscle and fatigability of facial and respiratory muscles commonly occurs. Patients are best treated in periods of remission while emotional stress, which can cause a disease crisis, must be reduced. Inhalational sedation is the most appropriate form of sedation since it has no effect on respiratory effort or muscle tone.

Sedation and endocrine disease Diabetes mellitus is a clinical syndrome characterised by hyperglycaemia due to absolute (type 1) or relative (type 2) insulin deficiency. The disease occurs worldwide and has a UK prevalence of 3%. It is defined as a random blood glucose of >11mmol/l. Type 1 diabetes is a slow T cell-mediated autoimmune disease in which genetic factors account for ~ 30% of susceptibility. Onset typically occurs at <40 years and is relatively rapid. In type 2 diabetes, genetic factors are more significant than in type 1, while age of onset is usually > 40 years and symptoms take months/years to develop. Three treatment methods are available: diet control alone, oral hypoglycaemics and insulin. Most type 1 diabetics are controlled on insulin. Most type 2 diabetics are controlled via diet or diet + oral hypoglycaemics. Glycaemic control is best monitored by measuring glycated haemoglobin (HbA1c) which gives an accurate estimation of control over the previous 6-8 weeks.

Patients who take insulin and those taking sulphonylureas e.g. glibenclamide are at risk of hypoglycaemia (a blood glucose < 3.5mmol/l).

It is important to establish the patient’s degree of diabetic control before planning treatment under sedation. Some practitioners also check the patient’s random blood glucose (using the patient’s own glucose monitor) immediately prior to treatment to reduce the risk of an intraoperative hypoglycaemic episode. All forms of sedation are appropriate for the well-controlled diabetic patient though staff must remember that sedation may cloud the patient’s ability to recognise the early symptoms of a ‘hypo’ and be mindful of this possibility during their clinical monitoring. Paradoxically people with very well controlled diabetes are more at risk of hypoglycaemia than those whose control is poor, since poor control usually leads to hyperglycaemia.

Sedation and liver and kidney disease Renal and hepatic diseases vary greatly in severity. Liver disease may reduce drug metabolism; kidney disease may reduce drug excretion so leading to increased blood drug levels. While oral, inhalational and intravenous sedation are appropriate in all but severe disease, it is sensible practice to consult the patient’s renal/hepatic physician prior to treatment.

Sedation and older people Care should be employed when sedating older people – both the chronologically and the biologically older person. With increasing age, the body systems have decreasing functional reserve and patients often have multiple system disease. Older people have reduced plasma protein binding of drugs and so increased drug is available to cross the blood-brain barrier and produce a sedative effect. For this reason, it is wise to administer sedatives in smaller increments with larger time intervals than normal, with particular care taken to avoid hypoxia. Sedationists must also be mindful of the potential lack of appropriate post-operative support.

Treatment environment Stable patients, i.e. those who are classified ASA 1 and 2 are suitable for operator sedation in general dental practice.

ASA 3 patients are less stable and signs/symptoms of deterioration may be masked by sedation. It is therefore appropriate to treat such patients in a specialised sedation environment (in primary or secondary care). Sometimes a separate sedationist is required to heighten the level of clinical monitoring available throughout.

ASA 4 patients have significantly unstable disease. A thorough risk assessment should consider whether dental treatment under sedation is the best way forward on an individual patient basis. Sedation may be best administered in an environment where medical support is available in the event of complications related to the underlying disease.

CONCLUSION

Conscious sedation is not always contraindicated for patients with a medical condition. Careful assessment and discussion with the patient’s medical advisor is sensible. Sedation techniques may decrease the likelihood of complications arising.

12 Psychological Approaches

Recognised as one of the most common specific phobias,1 dental phobia is estimated to affect 11% of the UK population2. While dental anxiety is common, it is helpful to consider it on a continuum, becoming a phobia when it meets the criteria outlined by the Diagnostic and Statistical Manual of Mental Disorders (DSM-5)3 (see Table 1). Specifically, this means the phobia has a significant impact on an individual’s wellbeing in areas of physiological, psychological or social functioning; with marked avoidance and experience of significant distress associated with encounters related to the dental setting.

Table 1. Diagnostic Criteria for Specific Phobia

DSM-5 300.29 Specific Phobia (APA,2013)

A. Marked and persistent fear that is excessive or unreasonable, cued by the presence or anticipation of a specific object or situation (e.g., flying, heights, animals, receiving an injection, seeing blood).

B. Exposure to the phobic stimulus almost invariably provokes an immediate anxiety response, which may take the form of a situationally bound or situationally predisposed panic attack. Note: In children, the anxiety may be expressed by crying, tantrums, freezing, or clinging.

C. The person recognises that the fear is excessive or unreasonable. Note: In children, this feature may be absent.

D. The phobic situation(s) is avoided or else is endured with intense anxiety or distress.

E. The avoidance, anxious anticipation, or distress in the feared situation(s) interferes significantly with the person's normal routine, occupational (or academic) functioning, or social activities or relationships, or there is marked distress about having the phobia.

F. In individuals under age 18 years, the duration is at least six months.

G. The anxiety, panic attacks or phobic avoidance associated with the specific object or situation are not better accounted for by another mental disorder...

A quick nod to Cognitive Behavioural Therapy (CBT)

The National Institute for Health and Clinical Excellence, (NICE, 2004)4 advocate Cognitive Behavioural Therapy (CBT) for a range of psychological disorders, including specific phobia. Indeed, the use of Cognitive Behavioural Therapy (CBT) for the long-term management of dental phobia has been well documented5 and has a strong evidence-base for both its efficacy (i.e. how well CBT interventions treat dental phobia)6,7 and its effectiveness (i.e. how well these CBT interventions work in “real-world” clinical settings).8,9 In a publication in the Royal College of Surgeons (England) Faculty Dental Journal, the complementary use of CBT within a conscious sedation care pathway has been endorsed;10 in which conscious sedation is deemed to provide an excellent approach to deliver dental care to the anxious individual, with CBT providing the long- term cure of the anxiety itself.

The rehabilitative benefits of CBT within the sedation care pathway were demonstrated in a case report published in the SAAD Digest in 2017,11 and further the rationale for services to develop sustainable care pathways to both care for and cure dental phobia.

For more information about CBT services for dental fear and training options in the approach, the SAAD Digest of 201812 included an article on this topic.

Managing dental anxiety proportionately

In a key paper which underpins this part of the course, dental anxiety is regarded at different levels (low, moderate, high), for which pharmacological and non-pharmacological management interventions are considered in relation to anxiety level and dental treatment need.13 The proportionate model is demonstrated below:

Figure 1: Proportionate Management Model

Assessment of dental anxiety is key – and there are a number of measures available to measure dental anxiety in adults and children. The Modified Dental Anxiety Scale (MDAS) provides a quick, reliable and robust measure and is freely available. Devised by Professor Gerry Humphris,14 this five-point scale has specific items relating to different aspects of dental treatment. It is easy to score, and patient’s scoring ≥ 19 or more are considered to be phobic of dental treatment. Note that a number of patients might score below <1 9 but be very anxious about specific aspects of dental treatment, such as local anaesthetic injections. A version has also been made for children – the Modified Child Dental Anxiety Scale (McDAS) – with eight items and a smiley-face five- point scale; this has been validated for 8-12-year-olds.15

IMPORTANT! In addition to identifying the level of dental anxiety for proportionate treatment planning, research has demonstrated the importance of dentists’ communication and recognition of an individual’s dental fears using the MDAS; reducing anxiety when it is done well and increasing distress when ignored.16

Components of anxiety

In psychological terms, activation of the sympathetic nervous system can be summarised in this model (see Figure 2). Anxiety has five components comprising: situational factors which are the triggers of the anxiety response, unhelpful thoughts, unhelpful behaviours, physical symptoms and emotional responses; in CBT this is referred to as the ‘Five areas model’ or ‘The Hot Cross Bun’ Model.17

Figure 2: Components of Dental Anxiety (Hot Cross Bun model)

This model provides a useful snapshot of anxiety, where specific tools and techniques based on psychological approaches can target specific anxiety components in order to reduce it. Additional benefits of this can enhance the role of pharmacological approaches.

Psychologically informed tools and techniques

There are a number of approaches that can help intercept the vicious cycles involved in dental anxiety, which can be employed at various time points of the patient’s assessment and treatment (see Table 2). In addition to the recommendation of assessing a patient’s level of anxiety, this talk covers seven areas of consideration.

Table 2. When? What to do: Every visit 1. Rapport Building (Communication) 2. Environmental change Initial consultation 3. Enhancing patient control 4. Preparatory Information Anxiety education / normalise 5. Managing physiological arousal: - Relaxation & Distraction Techniques - Preventing a faint – applied tension Night before treatment Relaxation/distraction/exercise techniques General relaxation: bath, TV, reading Diet advice: avoid caffeine and stimulants Day of treatment Environmental control - Friendly staff welcome - Avoid waiting time Enhancing patient control Relaxation/distraction/exercise techniques Post-treatment 6. Retrospective control Achievement acknowledged 7. Feedback positive coping

1. Rapport Building Independent of which treatment modality is employed, the treatment of anxiety starts with establishing a good rapport. While essential for all treatment, the pharmacological effect of anxiolysis is enhanced and reinforced by a good relationship, empathy and tell-show-do.

Matching verbal and non-verbal communication is important. Research has shown that in the communication of feelings, only 7% is communication by words – the rest is shown in non-verbal language (55%) and tone (38%).

That said, what we communicate is helpful to think about. Botto’s (2014)18 “4 As of Anxiety” provides a structure to consider – rather than well-intended reassurance, which has actually been found to be ineffective. Ask and Assess further demonstrate the importance of measuring anxiety, with Acknowledgment of concerns and offering suggestions to Address specific fears.

2. Environmental Change Consider the waiting area – emotions are contagious! Also consider training needs among those front-of-house staff that welcome patients on their arrival to the appointment.

Dental instrument noises you are familiar with are sirens to the anxious patient – consider what can be done to limit sound transmission from the dental surgery to the waiting area.

The smell of lavender has been shown to reduce adult anxiety on the day of treatment, although this is without altering beliefs of their global anxiety.19

The types of images shown in the waiting area have been shown to reduce anxiety among children,20 based upon theories of social learning and cognitive restructuring.

3. Enhancing Control Increasing an individual’s perception of control is key to reducing anxiety – think of yourself in other situations for which you feel that you lack control and how you may react.

The use of a STOP signal is simple, yet so effective;21 it can also be modified to be used as a communication tool with a rising hand – whereby a resting hand is low anxiety and raising the hand before reaching a full STOP sign would indicate increasing levels, which can be monitored and recognised by dentist and nurse.

The perception of choice also affords some control for individuals, which has been shown to be effective in both medical and dental settings.22

Writing a letter to the dentist (a technique coined by Professor Newton) has shown effective results in our work with dental patients; it is also a helpful way to contain patient information and put the control in the patient’s hands to let you know what the triggers are, and what helps them cope.

4. Preparatory Information Uncertainty is anxiety-provoking in any situation – patients do not know what is normal, particularly if they are infrequent attenders. Providing relevant information, either in verbal or written form is important, where three particular aspects are most salient to cover: procedural information, sensory information and coping information.23

5. Managing Physiological Arousal Providing techniques for individuals to manage their own anxiety is both empowering for the patient and timesaving for the clinician. Techniques to manage the uncomfortable physiology triggered by an anxiety response can be helpfully employed to reduce anxiety escalation.

Controlled breathing techniques (or diaphragmatic breathing) and Progressive Muscle Relaxation (PMR)24 have an established evidence base for anxiety reduction by reducing the sympathetic nervous system’s response before time would naturally dissipate anxiety. There are a number of techniques freely available online – and it is worth checking if individuals already engage in such exercises that they could try in the dental setting.

Applied Tension is an evidence-based technique25 to reduce the fainting response, by increasing heart rate and reducing the fall in blood pressure associated with the vaso-vagal response. This is particularly helpful for patients prone to fainting at the sight of blood, injections or injury.

6. Retrospective Control Enhancing control continues even after treatment has finished. Retrospective control is about helping the patients understand what happened and why – particularly if things do not go to plan,

or if a patient experiences discomfort or expected sensations. Reducing anxiety in this way has been associated with reduced experiences of pain post-operatively.26 This is also an important consideration if pharmacological approaches do not work as they intended; explaining possible reasons for this to the patient may prevent them from misinterpreting the situation and developing catastrophic beliefs.

7. Feedback Positive Coping Receiving praise, encouragement and labelling success and specifically asking the individual to identify these areas, after an anxiety-provoking event, can support the creation of helpful memories – as opposed to dwelling on the ‘things that didn't go well’. This technique conducted after treatment has been specifically demonstrated with children.27

References

1. Oosterink, F.M., de Jongh, A., & Hoogstraten, J. (2009). Prevalence of dental fear and phobia relative to other fear and phobia subtypes. Eurpean Journal of Oral Science, 117, 135-143. 2. Humphris, G., Crawford, J., Hill, K., Gilbert, A., & Freeman, R. (2013). UK population norms for the modified dental anxiety scale: Adult Dental Health Survey 2009 results. BMC Oral Health, 13: 29. 3. American Psychiatric Association. (2013). Diagnostic and statistical manual of mental disorders (5th ed.). Washington, DC. American Psychiatric Publishing. 4. NICE. (2004). Anxiety: Management of anxiety (panic disorder, with or without agoraphobia, and generalised anxiety disorder) in adults in primary, secondary and community care (http://guidance.nice.org.uk/CG22/guidance/pdf/English). 5. Öst L, Skaret E. Cognitive Behaviour Therapy for Dental Phobia and Anxiety. London: Wiley. 2013. 6. Kvale G, Berggren U, Milgrom P. Dental fear in adults: a meta-analysis of behavioural interventions. Community Dent Oral Epidemiol 2004; 32: 250-264. 7. Wide Boman U, Carlsson V, Westin M, Hakeberg M. Psychological treatment of dental anxiety among adults: a systematic review. Eur J Oral Sci 2013; 121: 225-234. 8. Kani E, Asimakopoulou K, Daly B, Hare J, Lewis J, Scambler S, Scott S, Newton J T. Characteristics of patients attending for Cognitive Behavioural Therapy at one specialist unit for dental phobia in the UK and outcomes of treatment. Br Dent J 2015; 219: 501-506. 9. Porritt J, Jones K, Marshman Z. Service evaluation of a nurse-led dental anxiety management service for adult patients. British dental journal. 2016 May 27; 220(10): 515-20. 10. Newton T, Gallagher J, Wong F. The care and cure of dental phobia: the use of cognitive behavioural therapy to complement conscious sedation. Faculty Dental J 2017; 8 (4): 160-163. 11. Hare, J., & Newton, J.T. (2018). Cognitive Behavioural Therapy (CBT) for dental phobia: services and training options for dental professionals. SAAD Digest, 34, 69-71. 12. Hare, J. (2017). Combining sedation and cognitive behavioural therapy (CBT) to overcome dental phobia: a case report. SAAD Digest, 33, 29-33. 13. Newton, T., Asimakopoulou, K., Daly, B., Scambler, S., & Scott, S. (2012). The management of dental anxiety: time for a sense of proportion? BDJ, 213, 271-274. 14. Humphris, G.M., Morrison, T., & Lindsay S.I.E. (1995). 'The Modified Dental Anxiety Scale: Validation and United Kingdom Norms' Community Dental Health, 12, 143-150. 15. Howards, K.E., & Freeman, R. (2007). Reliability and validity of a faces version of the Modified Child Dental Anxiety Scale. International Journal of Paediatric Dentistry, 17, 281-288. 16. Humphris , G M , Spyt , J , Herbison , A & Kelsey , T. (2016). Adult dental anxiety: recent assessment approaches and psychological management in a dental practice setting. Dental Update, 43 (4), 388-394. 17. Padesky, C.A. & Mooney, K.A. (1990). Presenting the cognitive model to clients. International Cognitive Therapy Newsletter, 6, 13-14. 18. Botto, R.W., Donate-Bartfield, E., & Nihill, P. (2014). Chairside techniques for reducing dental fear. In D.I Motofski, & F. Fortune (Eds), Behavioural Dentistry (2nd Ed., pp. 141-151). Oxford: Wiley

19. Kritsidima, M., Newton, T., & Asimakopoulou, K. (2010). The effects of lavender scent on dental patient anxiety levels: a cluster randomised controlled trial. Community Dentistry & Oral Epidemiology, 38: 83–87. 20. Fox, C., & Newton, J.T. (2006). A controlled trial of the impact of exposure to positive images of dentistry on anticipatory dental fear in children. Community Dentistry & Oral Epidemiology, 34: 455–459. 21. Richardson, P.H., Black, N.J., Justins, D.M., & Watson, R.J. (2009). The use of stop signals to reduce the pain and distress of patients undergoing a stressful medical procedure: an exploratory clinical study. British Journal of Medical Psychology, 72: 397–405. 22. Wardle, J. (1982). Management of dental pain. York: Paper presented at British Psychological Society. 23. Auerbach, S.M., Kendall, P. C., Cuttler, H.F., & Levitt, N.R. (1976). Anxiety, locus of control, type of preparatory information, and adjustment to dental surgery. Journal of Consulting & Clinical Psychology, 44: 809–818. 24. Jacobson, E. (1970). Modern treatment of tense patients. Springfield, IL: Thomas. 25. Ost, L., & Sterner, U. (1987). Applied tension. A specific behavioural method for treatment of blood phobia. Behaviour Research and Therapy. 25, 25-29. 26. Thompson, S.C. (1981). Will it hurt less if I can control it? A complex answer to a simple question. Psychological Bulletin, 90, 89-101. 27. Pickrell, J.E., Heima, M., Weinstein, P., Coolidge, T., Coldwell, S.E., Skaret, E., Castillo, J., & Milgrom, P. (2007). Using memory restructuring strategy to enhance dental behaviour. International Journal of Paediatric Dentistry, 17: 439–448.

13 Legal and Ethical issues

Sedation is intrinsically a very safe procedure to assist in the management of dentally anxious patients. However, if anything untoward does happen, the consequences can be disastrous, both on a professional and a personal level, for anyone involved. It is therefore important to have meticulous attention to detail in order to ensure compliance with all contemporary guidelines and standards.

A risk management approach is about improving the quality of care overall as much as minimising the risks associated with the provision of any particular type of care.

What is risk management? Risk management is a process which involves a number of different stages. There are different risk management models that can be applied.

• Risk Awareness This involves an awareness of the potential difficulties, how they arise and (just as importantly) where they can end up. • Risk Control This is about developing systems and strategies to minimise the risk of something untoward happening. • Risk Containment This works on the basis that in any environment risks, difficulties and problems inevitably occur and as a consequence things do go wrong. It is important to have strategies in place to minimise the impact of things that can go wrong • Risk Transfer This involves a sharing of risk or calling in additional help if things are beyond one’s control.

Where do the problems come from? There are a number of common areas where problems arise in sedation. These include: • Referral systems • Patient selection • Pre-operative assessments • Non evidence-based procedures • Poor operative technique • Poor knowledge of regulatory or legal requirements • Inadequate or poor training of sedationist and other team members • Inappropriate or outdated equipment

• Inherent risks / side-effects not recognised • Poor post-operative care • Inadequate chaperonage • Lack of clarity on the interface between private and NHS treatment

Where do the problems end up? 1. Complaints In most cases when a patient is dissatisfied with the process or treatment and wishes to take something further, the most likely avenue is a complaint. In the UK, for example, complaints can involve:

• Practice “in-house” complaint procedures • NHS Commissioning Boards / Clinical Commissioning Groups / Health Boards • The General Dental Council’s Private Patient Complaints process (The Dental Complaints Service) • Care Quality Commission • The NHS Ombudsman • Health and Safety Executive.

2. Claims Patients may also decide to make a civil claim for negligence or breach of contract and seek damages (compensation).

3. Dental Council and other Regulatory Bodies Complaints about a dental team member’s action in relation to sedation (whether as part of a treatment process or directly related to the provision of sedation) can be made to the regulators – i.e. General Dental Council (in the UK) or the Dental Council (in Ireland and other countries). If deemed serious these complaints are often investigated under the regulator’s fitness to practice procedures as a performance or a conduct issue. Please remember that dental councils can consider complaints from a variety of sources, not just patients.

4. Criminal process In rare circumstances the criminal processes can become involved. Such matters would usually include issues such as health and safety breaches, allegations of indecent assault, allegations of manslaughter or other criminal actions.

Appropriate Indemnity For obvious reasons given the problems that can occur, it is important for all clinical members of the dental team (including dental nurses) who are involved in the treatment of patients under sedation, to have full and appropriate indemnity.

Please be aware that unlike the conventional mutual indemnity providers, some insurance policies do not automatically provide indemnity for some types of sedation. It is then very important to check the policy “small print”. Similarly, some insurance policies, including trade union policies, are purely administrative (rather like motor or home insurance) and provide no advice line backup where clinicians can raise any clinical or ethical concerns they may have. When you’re in a tight spot, such advice can be invaluable.

When clinicians and members of the dental team are employed by a third party under a contract of employment, indemnity is invariably provided through the employer. This indemnity, however, will only provide assistance in claims in negligence and will not provide assistance for regulatory matters, if a complaint is made to the relevant dental council. It is then recommended that further “top up” indemnity is purchased from an appropriate indemnity provider, who has experience in assisting members of the dental team.

Clinicians who use a third party to provide sedation (i.e. a medically qualified anaesthetist or dentist) should also check to ensure that these individuals are appropriately qualified and indemnified.

What controls can be put in place?

1. A high quality and robust consent process

It is important for all practitioners to take adequate steps to ensure that the appropriate valid consent is received for the sedation procedure itself, in addition to the treatment to be provided. This means that all the relevant treatment options (including no sedation or treatment where appropriate) alongside possible costs, need to be fully discussed and agreed before any treatment begins.

Problems can arise when there are extra or additional treatment requirements that become evident once the patient is sedated. (i.e. RCT or extraction rather than a simple restoration). Such treatment possibilities should have been anticipated, discussed in full and agreed with the patient before any sedation is undertaken. It is then important to think outside the box rather than concentrating on one treatment option. Similarly, where the treatment is being provided by a clinician other than the one providing the treatment, it is important to ensure the patient understands who has the primary role in relation to consent for sedation and treatment.

Bear in mind that information in relation to sedation and some more complicated treatment options are often best provided in writing (clinical information sheet) in addition to a verbal discussion. Both actions should be fully recorded in the records for the avoidance of any doubt. Recent research shows that patients often have a better understanding of treatment when it is additionally explained to them by a non-clinician (e.g. treatment coordinator). All treatment should be explained using plain English, rather than technical terms.

The Dental Regulators in the UK and Ireland expect that consent for treatment provided under sedation will be confirmed by the patient signing a written consent form. The form should contain an explanation of the reasons for both the sedation and the dental treatment. The warnings given to the patient verbally should be confirmed on the form. The consent form should be signed either by the patient, or, where the patient is a child, a person with the appropriate legal authority.

The essential elements of a good consent process include:

The patient is able to make a decision • Autonomy without coercion.

The person has the ability to understand, assimilate and process the information necessary to make a decision and to convey that decision to the clinician. The onus is on the practitioner to make a reasonable assessment of a person’s capacity. Please be aware that a patient’s competency can change throughout a treatment process. Assessing that competency and acting appropriately is important at each stage of • Competence treatment so that the consent remains valid.

In the UK children under the age of 16 can, in some specific circumstances, be regarded as competent to make a decision on the provision of treatment (Gillick competency). This is a difficult area of law and therefore clinicians should seek advice, either from their indemnity provider or a suitably qualified solicitor before relying on this process.

The patient has been provided with sufficient and appropriate information to enable appropriate consent to be given. Currently the legal test that is used in the UK is the Bolam or “professional” test, i.e. as long as the person exercises a reasonable level of skill and care in accordance with a • Information body of professional opinion which could be regarded as reasonable, responsible and respectable, then they shall not be held to be negligent. This is a very fluid area of law and things can change. Please then keep up to date and if in doubt, seek advice before providing any treatment.

2. Good customer care systems that fulfil patient needs

These include: • Dealing with patient expectations • Giving patients value satisfaction • Treating patients with TLC • Treating patients with respect and dignity • Building rapport and trust

3. Quality records

The clinical records must be of a very high standard, particularly in relation to: • Medical history • Pre-operative assessment • Consent process • Written consent form • Pre- and post-operative instructions given • Sedation process including drugs used • Monitoring of clinical condition • Treatment provided

• Post-operative care and discharge • Details of post-operative supervision arrangements

4. Clear administrative protocols for:

• All types of emergencies • Complaints handling • Maintenance of equipment and drugs • Training and updating of all the team. It is important that training for emergency situations is up to date and recorded. If multiple drug sedation is employed there must be very clear advanced life support protocols available. Particular care should be taken to ensure that all support staff receive the appropriate training in dental sedation

5. Chaperone

Apart from the clear need to have a second trained and competent person present in the event of an emergency, it is important to be aware of the side-effects of many sedative drugs which include the possibility of hallucinations and erotic dreams or fantasies. A significant number of allegations have been made in the past in relation to sexual impropriety whilst treating sedated patients. In the absence of a chaperone such allegations may be almost impossible to refute. As a consequence, a suitably trained dental nurse or other clinician should remain with the treating clinician, whilst treatment is being undertaken.

6. Knowledge of local rules

The rules concerning the treatment of sedation within the NHS changed significantly from 1 April 2006. Unless specifically stated in the individual NHS contract, sedation is now provided as an additional service under separate contractual arrangements. It is generally not possible to mix private sedation and NHS treatment: Paragraph 10, Part 2 of Schedule III of the NHS (General Dental Services Contract) Regulations 2005 (Statutory Instrument No. 3361).

CONCLUSION

All registered clinical personnel must comply with and keep up to date with the constantly changing medico-legal framework under which we provide care.

14 Standards of Good Practice

Adopting a high standard of practice is not only necessary for the safety of the patient but also to reduce anxiety and increase comfort during the patient journey. Sedation practitioners and their team should critically analyse the patient journey from telephone contact and the arrival of the patient on the first occasion, to discharge at the end of the course of treatment. An audit by critical assessment of the patient journey, the knowledge, skills and training of the dental team, patient selection, technique selection, provision of the course of treatment, and protection of the patient in aftercare is the necessary pathway to high professional standards.

Of prime importance are the initial training and ongoing education, knowledge and skills of the dental team. Practitioners should only undertake specific techniques of conscious sedation in which they have received specific training and mentored practice.

It is incumbent on the practising sedationist to ensure that the team is familiar with, understands and complies with current regulatory guidance and policies. (All current guidance and policies can be found on the SAAD ‘publications’ website.) Good practice of conscious sedation should adopt contemporary guidelines and evidential research. There is a multiplicity of guidance available for practitioners. Slavish adherence to the protocol of an individual institution is inappropriate. Practitioners of conscious sedation should adopt a balanced approach to the contemporary guidance available and evidence-based research. There should be a clear delineation between pre-medication and conscious sedation and practitioners need to be aware of professional responsibilities where pre-medication is provided. Consideration of the definition of conscious sedation should be considered where sedatives are used primarily for anxiolysis rather than an intended sedative approach.

Below are listed a number of facets of the practice of conscious sedation of which critical analysis should be made by audit. This list is not exhaustive and is intended for guidance.

The environment

A calm, clean, well-organised comfortable surgery or clinic with minimal clutter and minimal fuss. • Location of surgery • Location of recovery area • Location of toilets • Clear surgery surfaces • Well-maintained equipment

Knowledge, skills and training

All members of the dental team, the sedationist, the dental nurses, hygienist/therapist and reception staff • Documented ongoing training • Adoption of regulatory guidance • Specific training in individual techniques • Practical team training • Management of complications • Evidential research

Patient care

Involvement of the patient, management of the patient journey and good record-keeping • Patient needs • Patient desires • Justification for sedation • Consent • Pre- and post-operative written instruction • Patient preparation • Technique selection • Escort provision and provision of patient-specific aftercare instruction • Expectations of aftercare • Records including psychological profile, patient assessment, conscious sedation procedure and discharge

The technique

Selection of technique appropriate to needs and desires and the proposed treatment plan • Pre-medication • Pre-operative assessment • Route of administration • Procedural technique • Monitoring • Recovery • Discharge • Complications.

Some other issues

• Understanding of legislation and regulation • Certification • Equipment maintenance • Drug classification and storage • Gas storage • Safe use of gases • Practice evaluation protocols • Referral systems • Pollution issues • Portable appliance safety • Decontamination/cleaning/sterilisation

CONCLUSION

A good standard of practice is maintained by constantly questioning the process by which anxious patients are provided with anxiety and pain control and updating the process appropriately.

Appendix 1