FIRST AID KIT

• A first aid kit is a collection of supplies and equipment for use in giving first aid

• can be put together for the purpose or

• purchased complete. Variation in the contents of first aid kits is based on:

• knowledge and experience of those putting it together • the differing first aid requirements of the area where it may be used, and • variations in legislation or regulation in a given area. Identification of FIRST AID KITs

• The international standard for first aid kits is that they should be identified with the ISO graphical symbol for first aid (from ISO 7010) which is an equal white cross on a green background • many kits do not comply with this standard, either because they are put together by an individual or they pre-date the standards.

ISO First Aid Symbol Alternate version of the first aid symbol Symbol of the Red Cross • all kits should be in a clean, waterproof container to keep the contents safe and aseptic

• Kits should also be checked regularly and restocked if any items are damaged or expired Containers

• plastic boxes • fabric pouches • wall mounted cabinets. **The type of containers vary depending on purpose, and they range in size from wallet sized through to large containers. Contents • Commercially available first aid kits available via normal retail routes have traditionally been intended for treatment of minor injuries only. • Typical contents include: – adhesive bandages – regular strength pain medication – gauze and – low grade disinfectant. Specialized first aid kits • are available for various regions – Vehicles – Activities, • may focus on specific risks or concerns related to the activity. • For example, first aid kits sold through marine supply stores for use in watercraft may contain seasickness remedies. Trauma injuries

– Bleeding – Bone fractures or – Burns • are usually the main focus of most first aid kits, with items such as: – bandages and – Dressings • being found in the majority of kits. Adhesive bandages

– band-aids, – sticking plasters • can include ones shaped for particular body parts, such as knuckles

– Moleskin— for blister treatment and prevention • Dressings - sterile, applied directly to a wound – Sterile eye pads – Sterile gauze pads – Sterile non-adherent pads, containing a non- stick teflon layer – Petrolatum gauze pads, used as an occlusive ( air-tight) dressing for sucking chest wounds, as well as a non-stick dressing

Bandages For securing dressings, not necessarily sterile- • Gauze roller bandages - absorbent, breathable, and often elastic • Elastic bandages - used for sprains, and pressure bandages • Adhesive, elastic roller bandages (commonly called 'Vet wrap') - very effective pressure bandages or durable, waterproof bandaging • Triangular bandages - used as slings, tourniquets, to tie splints, and many other uses

• Butterfly closure strips - used like stitches to close wounds, usually only included for higher level response as can seal in infection in un-cleaned wounds.

• Saline • -for cleaning wounds or washing out foreign bodies from eyes

• Soap - used with water to clean superficial wounds once bleeding is stopped

• Antiseptic wipes or sprays (iodine, alcohol) -for reducing the risk of infection in abrasions or around wounds. -Dirty wounds must still be cleaned for antiseptics to be effective. • Burn dressing -which is usually a sterile pad soaked in a cooling gel • Adhesive tapes, hypoallergenic • Hemostatic agents may be included in first aid kits, especially military or tactical kits, to promote clotting for severe bleeding.

Personal protective • Varies by equipmentkit, depending on its use and anticipated risk of infection. – Adjuncts to artificial respiration – Gloves - single use and disposable to prevent cross infection – Goggles or other eye protection – Surgical mask or N95 mask to reduce possibility of airborne infection transmission (sometimes placed on patient instead of caregivers. – Apron

Instruments and equipment • Trauma shears/scissors- for cutting clothing and general use • Tweezers • Lighter - for sanitizing tweezers etc. • Alcohol - pads for sanitizing equipment, or unbroken skin. -This is sometimes used to debride wounds, however some training authorities advise against this as it may kill cells which bacteria can then feed on

• Irrigation syringe - with catheter tip for cleaning wounds with sterile water, saline solution, or a weak iodine solution. - The stream of liquid flushes out particles of dirt and debris. • Torch/flashlight • Instant-acting chemical cold packs • Thermometer • Space blanket (lightweight plastic foil blanket, also known as emergency blanket/thermal blanket) – used to reduce heat loss

Medication • Life saving medications , which may be commonly found in first aid kits used by paid or assigned first aiders for members of the public or employees • Painkillers , which are often found in personal kits, but may also be found in public provision • Symptomatic relief medicines , which are generally only found in personal kits. • Life saving - Aspirin primarily used for chest pain and as an anti-coagulant

- Epinephrine autoinjector- often included in kits for wilderness use and in places such as camps, to treat anaphylactic shock.

Pain killers

• Paracetamol (Acetaminophen) - one of the most common pain killing medication, as either tablet or syrup • Anti-inflammatory painkillers such as: –Ibuprofen –Naproxen or –other NSAIDs • can be used as part of treating sprains and strains

• Codeine which is both a painkiller and anti-diarrheal Symptomatic relief

• Anti diarrhea medication such as – Loperamide - especially important in remote locations where dehydration caused by diarrhea is a leading killer of children

• Oral rehydration salts (ORS) • Antihistamine s, such as – Diphenhydramine – Chlorpheniramine • Poison treatments – Absorption, such as activated charcoal – Emetics to induce vomiting, such as syrup of ipecac although first aid manuals now advise against inducing vomiting.

• Smelling Salts (ammonium carbonate ) - Relieve blocked nostils - Fainting Topical medications • Antiseptic ointment, fluid, moist wipe or spray, including; –benzalkonium chloride –Neomycin –Polymyxin B Sulfate or –Bacitracin –Povidone iodine is an antiseptic Topical medications

–Aloe vera gel - used for a wide variety of skin problems, including –burns, –sunburns, –itching, and –dry skin; used as a substitute for triple-antibiotic gel to keep a wound moist and prevent bandages from sticking Topical medications • Burn gel - a water-based gel that acts as a cooling agent and often includes a mild anesthetic such as; – lidocaine and – an antiseptic such as tea tree oil • Anti-itch ointment – Hydrocortisone cream – Antihistamine cream containing diphenhydramine – Calamine lotion • Anti-fungal cream • Tincture of benzoin - protects the skin and aids the adhesion of butterfly strips or adhesive bandages. Emergency treatment of poisoning

• Patients who have features of poisoning should generally be admitted to hospital.

• Patients who have taken poisons with delayed action should also be admitted, even if they appear well Delayed-action poisons include; – Aspirin – Iron – Paracetamol, – Tricyclic antidepressants, and – co-phenotrope (diphenoxylate with atropine); –modified-release preparations. • A note of all relevant information, including what treatment has been given, should accompany the patient to hospital. • It is often impossible to establish with certainty the identity of the poison and the size of the dose.

• Fortunately this is not usually important because only a few poisons such as: – Opioids – Paracetamol and – Iron • have specific antidotes; few patients require active removal of the poison. • In most patients, treatment is directed at managing symptoms as they arise. • knowledge of the type and timing of poisoning can help in anticipating the course of events. • All relevant information should be sought from the poisoned individual and from carers or parents. • However, such information should be interpreted with care because it may not be complete or entirely reliable. • Sometimes symptoms arise from other illnesses and patients should be assessed carefully.

• Accidents may involve domestic and industrial products (the contents of which are not generally known). Effects of poisoning on Respiration • Respiration is often impaired in unconscious patients. • An obstructed airway requires immediate attention. • In the absence of trauma, the airway should be opened with simple measures such as chin lift or jaw thrust. • An oropharyngeal or nasopharyngeal airway may be useful in patients with reduced consciousness to prevent obstruction, provided ventilation is adequate

• Intubation and ventilation should be considered in patients whose airway cannot be protected or who have respiratory acidosis because of inadequate ventilation; such patients should be monitored in a critical care area

• Most poisons that impair consciousness also depress respiration. • Assisted ventilation (either mouth- to-mouth or using a bag-valve-mask device) may be needed. • Oxygen is not a substitute for adequate ventilation, • In poisoning with carbon monoxide and irritant gases, oxygen should be given in the highest concentration possible • Respiratory stimulants do not help and should be avoided. Effects of poisoning on Blood pressure

• Hypotension is common in severe poisoning with central nervous system depressants. • A systolic blood pressure of less than 70mmHg may lead to irreversible brain damage or renal tubular necrosis. • Hypotension should be corrected initially by tilting down the head of the bed and administration of either: – sodium chloride intravenous infusion or – a colloidal infusion. • Vasoconstrictor sympathomimetics are rarely required • Fluid depletion without hypotension is common after prolonged coma and after aspirin poisoning due to vomiting, sweating, and hyperpnoea.

• Hypertension, often transient, occurs less frequently than hypotension in poisoning; it may be associated with sympathomimetic drugs such as: – Amphetamines – phencyclidine, and – cocaine. Effects of poisoning on the Heart

• Cardiac conduction defects and arrhythmias can occur in acute poisoning, notably with: – Tricyclic antidepressants, – some Antipsychotics, and – some Antihistamines. • Arrhythmias often respond to correction of underlying; – Hypoxia – acidosis, or – other biochemical abnormalities • Ventricular arrhythmias that cause serious hypotension require treatment.

• If the QT interval is prolonged, specialist advice should be sought because the use of some anti- arrhythmic drugs may be inappropriate.

• Supraventricular arrhythmias are seldom life-threatening and drug treatment is best withheld until the patient reaches hospital. Effects of poisoning on the body temperature

• Hypothermia

• Hyperthermia • Hypothermia may develop in patients of any age who have been deeply unconscious for some hours, • Hypothermia may occur particularly following overdose with; – barbiturates or – phenothiazines. • Hypothermia may be missed unless core temperature is measured using a low-reading rectal thermometer

• Hypothermia is best treated by wrapping the patient (e.g. in a ‘space blanket’) to conserve body heat. • Hyperthermia can develop in patients taking CNS stimulants; children and the elderly are also at risk when taking therapeutic doses of drugs with antimuscarinic properties.

• Hyperthermia is initially managed by removing all unnecessary clothing and using a fan.

• Sponging with tepid water will promote evaporation; iced water should not be used. • Both hypothermia and hyperthermia require urgent hospitalisation for assessment and supportive treatment. Convulsions • Single short-lived convulsions do not require treatment. • If convulsions are protracted or recur frequently, – lorazepam 4 mg or – diazepam (preferably as emulsion) 10 mg • should be given by slow intravenous injection into a large vein. • Benzodiazepines should not be given by the intramuscular route for convulsions.

• If the intravenous route is not readily available, – diazepam can be administered as a rectal solution or – midazolam can be given by the buccal route Removal and elimination of a poison from the body

• Prevention of absorption

• Active elimination techniques

• Removal from the gastro - intestinal tract Prevention of absorption

• activated charcoal given by mouth can bind many poisons in the GI system, thereby reducing their absorption. • The sooner it is given the more effective it is, • may still be effective up to 1 hour after ingestion of the poison • May be effective longer in the case of modified release preparations or of drugs with antimuscarinic (anticholinergic) properties. • • It is relatively safe and is particularly useful for the prevention of absorption of poisons that are toxic in small amounts, such as antidepressants Active elimination techniques • Repeated doses of activated charcoal by mouth enhance the elimination of some drugs after they have been absorbed • repeated doses are given after over -dosage with: – Carbamazepine – Quinine – Dapsone – Theophylline – Phenobarbital Dose of activated charcoal

• The usual in adults and children over 12 years of age is; – 50 g initially then 50 g every 4 hours. • Vomiting should be treated (e.g. with an antiemetic drug) since it may reduce the efficacy of charcoal treatment • In cases of intolerance, the dose may be reduced and the frequency increased

– e.g. 25 g every 2 hours or 12.5 g every hour but this may compromise efficacy . • In children under 12 years of age, activated charcoal is given in a dose of: • 1 g/kg (max. 50 g) every 4 hours • the dose may be reduced and the frequency increased if not tolerated. Other techniques to enhance the elimination of poisons after absorption

• haemodialysis for: – Salicylates – Phenobarbital – Methyl alcohol (methanol) – ethylene glycol, and – lithium; • alkalinisation of the urine for; – salicylates and – phenoxyacetate herbicides- e.g. 2,4-dichloro-phenoxyacetic acid

**Forced diuresis is potentially harmful and no longer recommended. Removal from the gastro- intestinal tract • Gastric lavage is rarely required • Useful for substances that cannot be removed effectively by other means (e.g. iron), • it should be considered only if a life-threatening amount has been ingested within the previous hour. • Gastric lavage should be carried out only if the airway can be protected adequately. • Gastric lavage is contra-indicated if a corrosive substance or a petroleum distillate has been ingested • May occasionally be considered in patients who have ingested drugs that are not adsorbed by charcoal, such as iron or lithium. • Induction of emesis (e.g. with ipecacuanha) is not recommended because there is no evidence that it affects absorption and it may increase the risk of aspiration. Poisoning by Specific drugs

• Alcohol • Acute intoxication is common in adults but also occurs in children. • The features include: – Ataxia – Dysarthria – nystagmus, and – Drowsiness • Alcohol intoxication may progress to coma, with hypotension and acidosis. • Aspiration of vomit is a special hazard and hypoglycaemia • Patients are managed supportively, with particular attention to maintaining a clear airway and measures to reduce the risk of aspiration of gastric contents. • The blood glucose is measured and glucose given if indicated. Aspirin • Main features of salicylate poisoning; – Hyperventilation – Tinnitus – Deafness – vasodilatation, and – sweating. • Coma is uncommon but indicates very severe poisoning. • The associated acid-base disturbances are complex. • Treatment must be in hospital where the following can be measured: – plasma salicylate, – pH, and – electrolytes • absorption of aspirin may be slow and the plasma-salicylate concentration may continue to rise for several hours • This requires repeated measurement of plasma-salicylate concentration. • Plasma-salicylate concentration may not correlate with clinical severity in the young and the elderly, and clinical and biochemical assessment is necessary.

• Generally, the clinical severity of poisoning is low below a plasma- salicylate concentration of 500 mg/litre (3.6 mmol/litre). • Activated charcoal can be given within 1 hour of ingesting more than 125 mg/kg of aspirin.

• Fluid losses should be replaced and intravenous sodium bicarbonate may be given to enhance urinary salicylate excretion (optimum urinary pH 7.5–8.5). • Haemodialysis is the treatment of choice for severe salicylate poisoning

• Haemodialysis should be considered when the plasma- salicylate concentration exceeds 700 mg/litre (5.1 mmol/litre) or • in the presence of severe metabolic acidosis. Mefenamic acid

• has important consequences in over-dosage • can cause convulsions • if prolonged or recurrent, the convulsions would require treatment Ibuprofen • Overdosage with ibuprofen may cause: – Nausea – Vomiting – epigastric pain and – Tinnitus • more serious toxicity is very uncommon. • Activated charcoal followed by symptomatic measures are indicated if more than 400 mg/kg has been ingested within the preceding hour Paracetamol

• Single or repeated doses totalling as little as: – 10–15 g (20–30 tablets) or – 150 mg/kg of paracetamol • taken within 24 hours may cause – severe hepatocellular necrosis and, – renal tubular necrosis (less frequent) • Patients at high-risk of liver damage include: – those taking enzyme-inducing drugs or – who are malnourished • may develop liver toxicity with as little as; – 75 mg/kg of paracetamol – (equivalent to approx. 5 g (10 tablets) • in a 70-kg patient) taken within 24 hours. Early features of paracetamol poisoning

–Nausea and –vomiting • usually settle within 24 hours. • Persistence beyond this time, often associated with the onset of right subcostal pain and tenderness, usually indicates development of hepatic necrosis. • Liver damage is maximal 3–4 days after ingestion and may lead to: – encephalopathy, – Haemorrhage – Hypoglycaemia – cerebral oedema, and – death . • Patients who have taken an overdose of paracetamol should be transferred to hospital urgently despite lack of significant early symptoms • Administration of activated charcoal should be considered;
if paracetamol in excess of 150 mg/kg or 12 g, • whichever is the smaller, is thought to have been ingested within the previous hour. • Acetylcysteine protects the liver if infused within 24 hours of ingesting paracetamol. • It is most effective if given within 8 hours of ingestion, after which effectiveness declines sharply Methionine

• In remote areas methionine by mouth is an alternative only if acetylcysteine cannot be given promptly. • Once the patient reaches hospital the need to continue treatment with the antidote will be assessed from the plasma-paracetamol concentration • Patients taking enzyme-inducing drugs e.g. – Carbamazepine – Phenobarbital – Phenytoin – Primidone – Rifampicin – Alcohol and – St John’s wort • may develop toxicity at lower plasma-paracetamol concentrations • Those who are malnourished e.g. – in anorexia – in alcoholism – HIV positive – following a few days of acute starvation, • may also develop toxicity at lower plasma-paracetamol concentrations

***If there is doubt about timing or the need for treatment then the patient should be treated with an antidote. Opioid Analgesics

• Opioids (narcotic analgesics) cause; – Coma – Respiratory depression, and – pinpoint pupils • The specific antidote naloxone is indicated if there is coma or bradypnoea • Since naloxone has a shorter duration of action than many opioids; – close monitoring and – repeated injections • are necessary according to the respiratory rate and depth of coma. • When repeated administration of naloxone is required, it can be given by continuous intravenous infusion instead and the rate of infusion adjusted according to vital signs. • The effects of some opioids such as buprenorphine, are only partially reversed by naloxone

• Dextropropoxyphene and methadone have very long durations of action patients may need to be monitored for long periods following large overdoses. • Naloxone reverses the opioid effects of dextropropoxyphene • the long duration of action of dextropropoxyphene calls for prolonged monitoring and further doses of naloxone may be required. • Norpropoxyphene, a metabolite of dextropropoxyphene, also has cardiotoxic effects which may require treatment with; – Sodium bicarbonate, or – magnesium sulphate, or both Antidepressants • Tricyclic and related antidepressants cause; – dry mouth – coma of varying degree, – hypotension, – hypothermia, – Hyper-reflexia – overactive reflexes – extensor plantar responses – convulsions – Respiratory failure – cardiac conduction defects – arrhythmias – Dilated pupils and urinary retention also occur. • Metabolic acidosis may complicate severe poisoning • Delirium with confusion, agitation, and visual and auditory hallucinations are common during recovery. • Transfer to hospital is strongly advised in case of poisoning by tricyclic and related antidepressants • Symptomatic treatment and activated charcoal can be given before transfer. • Supportive measures to ensure a clear airway and adequate ventilation during transfer are mandatory • Intravenous lorazepam or intravenous diazepam (preferably in emulsion form) may be required to treat convulsions • Although arrhythmias are worrying, some will respond to correction of hypoxia and acidosis.

• Avoid the use of anti-arrhythmic drugs but intravenous infusion of sodium bicarbonate can arrest arrhythmias or prevent them in those with an extended QRS duration.

• Diazepam given by mouth is usually adequate to sedate delirious patients but large doses may be required. Antimalarials

• Overdosage with; – Quinine – Chloroquine – hydroxychloroquine • is extremely hazardous and difficult to treat • Life-threatening features include – arrhythmias (which can have a very rapid onset) & – convulsions (which can be intractable) Hypnotics and anxiolytics Benzodiazepines taken alone cause; – Drowsiness – Ataxia – Dysarthria and • occasionally minor and short-lived depression of consciousness. • Activated charcoal can be given within 1 hour of ingesting a significant quantity of benzodiazepine. • Benzodiazepines potentiate the effects of other central nervous system depressants taken concomitantly. • flumazenil is a benzodiazepine antagonist Iron salts • Iron poisoning is commonest in childhood and is usually accidental. • The symptoms are: – Nausea – Vomiting – abdominal pain – Diarrhoea – haematemesis – rectal bleeding. – Hypotension – coma, and – hepatocellular necrosis (can occur later) • Mortality is reduced by intensive and specific therapy with desferrioxamine • Desferrioxamine chelates iron. • The serum iron concentration is measured as an emergency and intravenous desferrioxamine given to chelate absorbed iron in excess of the expected iron binding capacity. • In severe toxicity intravenous desferrioxamine should be given immediately without waiting for the result of the serum-iron measurement. Lithium

• Most cases of lithium intoxication occur as a complication of long-term therapy and are caused by reduced excretion of the drug due to a variety of factors including; – Dehydration – deterioration of renal function – infections, and – co-administration of diuretics or NSAIDs (or other drugs that interact) • Acute deliberate overdoses may also occur with delayed onset of symptoms (12 hours or more) owing to: – slow entry of lithium into the tissues and – continuing absorption from modified-release formulations. • The early clinical features are non-specific and may include; – apathy and – Restlessness • These may be confused with mental changes arising from the patient’s depressive illness. – Vomiting – Diarrhoea – Ataxia – weakness – Dysarthria – muscle twitching, and – Tremor • may follow. • Severe poisoning is associated with – convulsions, – Coma – renal failure – electrolyte imbalance – Dehydration & – hypotension. • Therapeutic lithium concentrations are within the range of 0.4–1.0 mmol/litre

• concentrations in excess of 2.0 mmol/litre are usually associated with serious toxicity and such cases may need treatment with haemodialysis if neurological symptoms or renal failure are present • In acute overdosage much higher serum-lithium concentrations may be present without features of toxicity and all that is usually necessary is; »to increase urine output (e.g. by increasing fluid intake but avoiding diuretics) • Lithium poisoning treatment is usually supportive with special regard to; – electrolyte balance – Renal function, and – control of convulsions. • The stomach should be emptied by gastric lavage if it can be performed within 1 hour of ingesting significant quantities of lithium. Stimulants • Amphetamines cause; –Wakefulness –Excessive activity –Paranoia –hallucinations, and –hypertension followed by; • Exhaustion • Convulsions • hyperthermia, and • coma. • The early stages of stimulant poisoning can be controlled by; – Diazepam or – lorazepam • management of hypertension. • tepid sponging • anticonvulsants, and • artificial respiration may be needed. Cocaine • Cocaine stimulates the central nervous system , • Causes – Agitation – dilated pupils – tachycardia – Hypertension – hallucinations – Hyperthermia – hypertonia, and – Hyper-reflexia • cardiac effects include – chest pain, – myocardial infarction and arrhythmias.

• Initial treatment of cocaine poisoning involves intravenous administration of: – diazepam to control agitation and – cooling measures for hyperthermia

• hypertension and cardiac effects require specific treatment and expert advice should be sought. Theophylline • Theophylline and related drugs are often prescribed as: – modified-release formulations and – toxicity can therefore be delayed. • They cause – vomiting (may be severe and intractable), – Agitation, Restlessness – dilated pupils – sinus tachycardia, and – hyperglycaemia. • More serious effects of theophylline poisoning are; – Haematemesis – Convulsions – Supraventricular and ventricular arrhythmias. – Severe hypokalaemia may develop rapidly. • Repeated doses of activated charcoal can be used to eliminate theophylline even if more than 1 hour has elapsed after ingestion and especially if a modified release preparation has been taken • Ondansetron may be effective for severe vomiting that is resistant to other antiemetics • Hypokalaemia is corrected by intravenous infusion of potassium chloride • Convulsions should be controlled by intravenous administration of lorazepam or diazepam • Sedation with diazepam may be necessary in agitated patients. • Provided the patient does not suffer from asthma, a short-acting beta -blocker can be administered intravenously to reverse severe tachycardia, hypokalaemia, and hyperglycaemia Ethylene glycol and methanol

• Ethanol – by mouth or – by intravenous infusion • is used for the treatment of ethylene glycol or methanol (methyl alcohol) poisoning • Fomepizole has also been used for the treatment of ethylene glycol or methanol poisoning. Heavy metals

• poisoning by: – Antimony – Arsenic – bismuth – Gold – mercury • Heavy metal antidotes include: – dimercaprol and – Sodium calcium edetate

• Other antidotes include: – succimer (DMSA) and – unithiol (DMPS ) Tear Gas

• CS spray, which is used for riot control, irritates the eyes and the respiratory tract • Symptoms normally settle spontaneously within 15 minutes. • If symptoms persist, the patient should be removed to a well- ventilated area, and the exposed skin washed with soap and water after removal of contaminated clothing. • Contact lenses should be removed and rigid ones washed (soft ones should be discarded). • Eye symptoms should be treated by irrigating the eyes with physiological saline • or water if saline is not available and • advice sought from an ophthalmologist. • Patients with features of severe poisoning, particularly respiratory complications, should be admitted to hospital for symptomatic treatment. Noxious gases

• Carbon monoxide • Sulphur dioxide • Chlorine • Phosgene • Ammonia • Carbon monoxide poisoning is usually due to inhalation of: – Smoke – car exhaust, or – fumes caused by blocked flues or – incomplete combustion of fuel gases in confined spaces. • Immediate treatment of carbon monoxide poisoning is essential. • The person should be – moved to fresh air, – The airway cleared, and – oxygen 100% administered through a tight-fitting mask with an inflated face seal. – Artificial respiration should be given as necessary • The patient should be admitted to hospital because complications may arise after a delay of hours or days. • Cerebral oedema should be anticipated in severe CO poisoning and is treated with an intravenous infusion of mannitol Sulphur dioxide, chlorine, phosgene, ammonia

• All of these gases can cause upper respiratory tract and conjunctival irritation. • Pulmonary edema, with severe breathlessness and cyanosis may develop suddenly up to 36 hours after exposure. • Death may occur. • Patients should be kept under observation and those who develop pulmonary oedema are given oxygen. • Assisted ventilation may be necessary in the most serious cases. Pesticides

• Organophosphorus insecticides are usually supplied as powders or dissolved in organic solvents. • All are absorbed through; – the bronchi – intact skin – the gut • They inhibit cholinesterase activity, thereby prolonging and intensifying the effects of acetylcholine. • common features of organophosphorus poisoning – Anxiety – Restlessness – Dizziness – Headache – miosis, – Nausea – Hyper-salivation – Vomiting – abdominal colic – Diarrhoea – bradycardia, and – sweating • Muscle weakness and fasciculation may develop and progress to generalised flaccid paralysis, including the ocular and respiratory muscles.

• Convulsions, coma, pulmonary edema with copious bronchial secretions, hypoxia, and arrhythmias occur in severe cases

• Hyperglycaemia and glycosuria without ketonuria may also be present. • Further absorption of the organophosphorus insecticide should be prevented by: – moving the patient to fresh air – removing soiled clothing, and – washing contaminated skin • In severe poisoning it is vital to ensure – a clear airway – frequent removal of bronchial secretions – adequate ventilation and oxygenation – gastric lavage may be considered provided that the airway is protected. • Atropine will reverse the muscarinic effects of acetylcholine and is given in a dose of: – 2 mg as atropine sulphate – (20 micrograms/kg (max. 2 mg) in a child) – i.m or i.v • according to the severity of poisoning every 5 to 10 minutes until: – the skin becomes flushed and dry – the pupils dilate and – tachycardia develops. • Pralidoxime chloride - a cholinesterase re-activator

• is used as an adjunct to atropine in moderate or severe poisoning.

• It improves muscle tone within 30 minutes of administration

• Pralidoxime chloride is continued until the patient has not required atropine for 12 hours Snake bites and animal stings

• A snake bite may cause local and systemic effects. • Local effects include: – Pain – Swelling – bruising, and – tender enlargement of regional lymph nodes • Systemic effects include: • early anaphylactoid symptoms – Transient hypotension with syncope, – Angioedema – Urticaria – Abdominal colic – Diarrhoea, and vomiting • later effects include: – persistent or recurrent hypotension – ECG abnormalities – spontaneous systemic bleeding – Coagulopathy – adult respiratory distress syndrome, and – acute renal failure. • Early anaphylactoid symptoms should be treated with adrenaline (epinephrine). • Indications for antivenom treatment include; – systemic envenoming - especially hypotension – ECG abnormalities – Vomiting – haemostatic abnormalities, and – marked local envenoming such that after bites on the hand or foot, swelling extends beyond the wrist or ankle within 4 hours of the bite. • For both adults and children, the contents of one vial -10 mL venom antiserum is given by; – intravenous injection over 10–15 minutes or – by intravenous infusion over 30 minutes after diluting in sodium chloride intravenous infusion 0.9% (use 5mL diluent /kg bodyweight) • The dose can be repeated in 1–2 hours if symptoms of systemic envenoming persist. • Adrenaline injection must be immediately to hand for treatment of anaphylactic reactions to the antivenom Insect stings • Ants, Wasps, Hornets, and bees cause; – local pain and – Swelling – seldom cause severe direct toxicity unless many stings are inflicted at the same time. • If the sting is in the mouth or on the tongue local swelling may threaten the upper airway. • The stings from these insects are usually treated by cleaning the area with a topical antiseptic • Bee stings should be removed as quickly as possible.

• Anaphylactic reactions require immediate treatment with intramuscular adrenaline

• self-administered intramuscular adrenaline is the best first -aid treatment for patients with severe hypersensitivity. • An inhaled bronchodilator should be used for asthmatic reactions. • A short course of; – an oral antihistamine or – a topical corticosteroid • may help to reduce inflammation and relieve itching. • A vaccine containing extracts of bee and wasp venom can be used to reduce the risk of anaphylaxis and systemic reactions in patients with systemic hypersensitivity to bee or wasp stings