92 Clinical
Clinical The management of acute shortness of breath in young adults
V Y Ahuja, D Freshwater
Abstract
Shortness of breath (SOB), or dyspnoea, is a common presenting symptom in acute care, responsible for 8% of all 999 calls to the ambulance service and ranking as the third most common type of emergency call (1). It may be associated with significant pathology, so prompt identification and appropriate management are therefore imperative. Although a formal diagnosis guides risk stratification, prognostication and treatment, it must not delay resuscitation. Rather, the management of an acutely short of breath (ASOB) patient must follow an algorithm incorporating simultaneous assessment and resuscitation. This article discusses both of these aspects in some detail, as well as key features in the history and the differential diagnosis, before concluding with some consideration of how the different operational environments in which such patients can present may affect their management.
Introduction Along with tachypnoea and perhaps tachycardia, there may The American Thoracic Society defines dyspnoea as: be associated symptoms such as chest pain, nausea and “A subjective experience of breathing discomfort that vomiting, cough, sweating, fevers, and/or palpitations, all of consists of qualitatively distinct sensations that varies which may assist in formulating a diagnosis. in intensity” (2). Acute dyspnoea is shortness of breath For the purposes of this article we shall assume that that has developed over seconds, minutes, hours or days. ASOB exists when, over a period of minutes, hours or days, Breathlessness can be physiological, almost exclusively a patient has developed any one (or more) of the following: in association with increased physical exertion. In this 1) Tachypnoea. case, the increased work of breathing is proportional to 2) The subjective experience of breathing discomfort. the perceived level of exertion. In this article we discuss 3) Subnormal SaO2 (patient specific but we shall assume pathological breathlessness experienced in situations not <94% except in cases of COPD). normally associated with laboured breathing. The resuscitation of a patient with ASOB follows an A to E In general, apart from when due to anxiety or pain, algorithm. In the context of trauma, the algorithm is
Table 1. Differential diagnosis for a medical patient with ASOB and associated clinical features
Diagnosis Associated clinical features Sudden onset; associated with chest pain and cough. Past medical history; more likely in asthmatics and Pneumothorax tall, thin, male smokers Anaphylaxis Lip swelling, urticarial rash, wheeze, shock; known allergy (may carry an EpiPen®) Pulmonary embolus (PE) Chest pain, cough, haemoptysis, shock; may have evidence of DVT; may have previous history or risk factors Pneumonia Fever, cough, haemoptysis, chest pain; evidence of consolidation on examination Myocardial infarction Chest pain, nausea and vomiting, sweating; cardiac risk factors Airway obstruction Noisy breathing; may be history of foreign body inhalation/choking, burns, history suggestive of anaphylaxis Asthma/COPD Wheeze; generally previous history of asthma/COPD Diabetic ketoacidosis Known type 1 diabetic or new diagnosis (history of polydipsia, polyuria, malaise, weight loss) Sepsis Fever; symptoms specific to focus of infection Gradual onset; associated chest pain; quiet breath sounds, stony dull percussion note; Pleural effusion contralateral tracheal deviation in large effusions Hyperventilation Diagnosis of exclusion; patient often anxious/emotional
Table 2. ASOB in trauma (taken from BLATOMFC in BATLS – life-threatening chest injuries) (3).
Prehospital management (in Cause Clinical features Definitive management addition to O2) History of blast; reduced breath sounds; Blast Lung haemoptyisis. May be minimal external Supportive Supportive signs of chest injury. Clear airway; jaw thrust; Airway compromise Stridor, gargling etc; central cyanosis adjuncts; cricothyroidotomy; Surgical airway; intubation surgical airway As for pneumothorax with signs of shock; Needle thoracocentesis; Tension Pneumothorax distended neck veins; tracheal deviation Chest drain consider chest drain (contralateral to the affected side) Ipsilateral: reduced chest movement; (Open) Pneumothorax reduced breath sounds; hyper-resonant Consider chest drain Chest drain percussion note Signs of shock; ipsilateral: reduced chest (Massive) Haemothorax movement; reduced breath sounds; dull iv fluids; consider chest drain Chest drain percussion note Flail chest Paradoxical movement of portion of chest wall Analgesia Analgesia
Signs of shock; distended neck veins; Clamshell thoracotomy (if Clamshell thoracotomy; other Cardiac tamponade muffled heart sounds; pulsus paradoxus available) (6) cardiothoracic surgery
Arrest of bleeding; leg iv fluids (including blood); Hypovolaemia Signs of shock elevation; iv fluids surgery Overlying bruising or rib fractures; reduced Lung contusions Supportive Supportive breath sounds; dull percussion note
Patient reports pain; physiological derangement Pain Analgesia Analgesia disproportionate to identifiable injuries
A - Airway to assess breathing. If not, airway compromise must be In the majority of cases, ASOB is conspicuous and the excluded. In the latter case, there may be additional noises patient looks distressed and unwell. Having taken note of such as stridor, gargling and snoring. the patient’s overall condition, airway assessment follows Firstly, inspect the airway and if an obstructing foreign with a rapid and extremely informative test, which is to ask body is noted this should be removed under direct vision the patient to count aloud from one to ten in one breath. As (ideally with Magill’s forceps). If there are obstructing well as confirming the patency of the airway, it provides a secretions or vomit, use suction. Never perform a blind rapid insight into the severity of SOB. If the patient is able finger sweep as you may propel any foreign body distally to speak normally, the airway is patent and you may proceed into the airway. In the absence of either, perform an airway 94 Clinical
opening manoeuvre such as a head tilt/chin lift or jaw Oxygen thrust (particularly used in trauma). Having opened the Having secured the airway, high-flow oxygen should be airway, an adjunct may be required to maintain it, such as a given. In the acutely unwell patient, this will be 12–15 L/min nasopharyngeal or oropharyngeal airway (which is generally through a non-rebreathing mask (4). This may subsequently poorly tolerated in the conscious patient). If, in spite of be titrated to SaO2 94–98% (4). Hypoxia (low oxygen) taking all of the above actions the airway is still inadequate, will kill before hypercarbia (high/rising carbon dioxide). time is critical and in the absence of an airway specialist Furthermore, in our Service population we do not see COPD (e.g. an anaesthetist) a surgical airway may be required. patients who rely on hypoxia for their ventilatory drive. While awaiting urgent evacuation, you should proceed to After securing the airway and giving oxygen, breathing resuscitate the patient as below. must be assessed.
Table 3. ‘RISE N FALL’ breathing assessment B - Breathing As for the airway, when managing B it is necessary to R Respiratory rate simultaneously assess and resuscitate. There are numerous I Injuries mnemonics which may useful in the assessment of B. ‘RISE N FALL’, although derived from Battlefield Advanced S Symmetry of chest movement Trauma Life Support (BATLS), can be used in the medical E Effort of breathing patient although ‘IPPA’ is more commonly used. Tables N Neck 3 and 4 show the component parts of these two systems. Crucial parameters assessed during B are RR and SaO2, T Trachea documenting how much oxygen the patient is receiving and W Wounds how. These measures indicate the severity of the patient’s E Emphysema (surgical) SOB, whilst also providing a baseline against which to L Larynx observe any subsequent trend in the patient’s condition. Table 5 lists the common examination findings, with V Veins their associated implications. E Every time F Feel C - Circulation Any impairment in C will cause inadequate systemic A Assess resonance oxygen delivery and therefore lead to ASOB. In trauma, L Listen (auscultation with stethoscope) the assessment of C is guided by “blood on the floor and L Look at the back four more”, the four more referring to the chest, abdomen, pelvis and femoral bones. Additionally, in both medical and trauma patients, we assess central and peripheral capillary Table 4. ‘IPPA’ breathing assessment refill, the rate, character and volume of the radial pulse and I Inspection the blood pressure. We may assess skin turgor if we suspect dehydration, which is relevant to the medical patient. It P Palpation is necessary to gain intravenous (iv) access and possibly P Percussion to begin fluid resuscitation, generally with crystalloids in A Auscultation boluses of 250–500 ml. In the first hour after time of injury
Table 5. Possible examination findings and likely implications in the breathing assessment of the medical patient with ASOB
Clinical sign Associated pathology Treatment Hyper-expanded chest Air trapping in association with asthma/COPD As for asthma/COPD Asymmetrical chest movement Spontaneous pneumothorax; pleural effusion Observation; aspiration; chest drain Dull percussion note Consolidation in association with infection Antibiotics “Stony” dull percussion note Pleural effusion Pleural tap; chest drain Hyper-resonant percussion note Spontaneous pneumothorax As above Quiet/absent breath sounds Pneumothorax; pleural effusion; lung collapse As above; depending on cause for collapse Inspiratory crackles Infection; heart failure Antibiotics; as for heart failure As for asthma/COPD; adrenaline/chlorphe- Expiratory wheeze Asthma/COPD; anaphylaxis niramine/steroids/ bronchodilators J Royal Naval Medical Service 2013, Vol 99.3 95
in the trauma patient, do not administer iv fluids if there is towards certain diagnoses. a radial pulse, with the exceptions of: 1. penetrating torso trauma - titrate to a carotid pulse (5); and 2. pregnancy History or head injury - titrate to normotension. However, in the An extremely important element that should proceed in medical patient, fluids are administered in any suspicion of parallel with the assessment and resuscitation is history- hypovolaemia and/or dehydration. Note that in previously taking. If the patient is too breathless to speak, seek a fit and healthy young adults we are unlikely to overload a collateral history (if available) and determine whether patient through the cautious use of iv fluids. there is any prior medical history available on the Defence Medical Information Capability Program (DMICP) D - Disability computer system. Assess for medic alert bracelets (allergy, In D, we assess pupillary responses and the patient’s chronic disease) and other things which may aid diagnosis conscious level, initially via the ‘AVPU’ scale (Alert; (e.g. inhalers, an EpiPen® or antibiotics etc.). responding to Voice; responding to Pain; Unresponsive) and Table 6 gives some of the key questions you should then more formally using the Glasgow Coma Scale (GCS) consider asking in the history, together with differential once the patient has stabilized. With respect to ASOB, the diagnoses. particular relevance of conscious level is related to patency of the airway. At or below an AVPU scale of P, the patient’s Severity innate protective airway reflexes may be lost and the airway Any of the following, if present, suggest a severe episode of becomes much more vulnerable. Furthermore, a patient ASOB which requires immediate attention (1): with reduced consciousness is generally more unwell and it 1) Inability to speak in complete sentences. may be the ASOB, and potentially associated reduced oxygen 2) RR >25 breaths per minute. uptake and/or delivery, that is the cause. Note: because 3) HR >110 beats per minute. either hypo- or hyperglycaemia (most likely in association 4) Supplemental oxygen required to maintain SaO2>95%. with diabetic ketoacidosis) may cause ASOB, “don’t ever forget glucose”. A patient with severe SOB may begin to tire, in which case their RR, HR, BP and conscious level may decline. This is E - Exposure particularly the case in life-threatening asthma. Full exposure of the patient (whilst preserving dignity) is also important, as it may reveal subtle signs not elucidated by Subsequent management the history and examination thus far. Exposure assessment Following assessment and resuscitation as detailed above, is particularly important in the unconscious patient. A ongoing management will be determined to a large extent purpuric rash (meningococcal septicaemia), an urticarial by the severity of the patient’s condition and the presumed rash (anaphylaxis), stigmata of chronic disease (e.g. chronic underlying diagnosis. One must also be mindful of the liver disease, diabetes) or calf redness/tenderness (deep influence of the surroundings and environment. vein thrombosis (DVT)) resulting in a pulmonary embolus (PE) may be associated with ASOB. It is also important to The shore-based sickbay. measure the temperature during E as a febrile patient is Help should be readily available here and sought early. often tachypnoeic and the presence of a temperature points By this stage, there should be at least one doctor and one
Table 6. Key questions in the history of an ASOB patient
Question Relevance
When did your symptoms start? Sudden onset - pneumothorax, PE, anaphylaxis, cardiac ischaemia Did the symptoms come on suddenly or gradually? Gradual onset - asthma/COPD, pneumonia, diabetic ketoacidosis
Are there any associated symptoms? Specifically ask about chest Chest pain - pneumothorax, PE, pneumonia, cardiac ischaemia pain, cough (and associated sputum/blood), fever, palpitations, Cough - pneumonia, PE, pneumothorax, asthma/COPD breathlessness on lying flat. Fever - pneumonia, infective exacerbation of asthma/COPD, PE Have you experienced similar symptoms in the past? If so, what May be recurrence of previous problem was the diagnosis? Do you have any pre-existing illness? E.g. asthma, diabetes, May be exacerbation/recurrence known allergy, previous pneumothorax, previous DVT/PE Look for risk factors for DVT/PE If present, increase likelihood of DVT/PE Pneumothorax and pneumonia more common in smokers; Are you a smoker? undiagnosed COPD? 96 Clinical
medical assistant in attendance. will be inserted before CASEVAC as it may be impractical Cases other than mild SOB will likely require referral to perform the procedure in transit. The decision to insert a to hospital for further assessment and/or treatment. If the chest drain is case-specific. patient is severely SOB (and also depending on the likely diagnosis), an emergency ‘999’ call may be needed. In a forward operating base (FOB). The management of an ASOB patient in a FOB will be Aboard a unit at sea. constrained in a similar way to cases seen aboard a unit at A patient will likely require casualty evacuation (CASEVAC) sea, and hence will entail similar decision-making processes. from the platform in all cases other than mild and self- Differences largely reflect time to evacuation. limiting SOB, as treatment options aboard a ship or submarine are severely limited. The severity, likely diagnosis Summary and operational situational will all affect the method Acute shortness of breath is a common and potentially serious and speed of CASEVAC but, if available, a helicopter will presenting complaint. In this review we have discussed a generally be preferred as the fastest method of extraction. safe and thorough approach to the ASOB patient based on As CASEVAC from such units will take longer than simultaneous assessment and resuscitation, following an for cases at a shore-based sickbay, it may be necessary to A to E algorithm. We have considered key questions in the start further treatment, for example iv fluids, antibiotics, history, possible examination findings and the differential bronchodilators and/or steroids if indicated. diagnosis. We have discussed some of the operational If the diagnosis includes pneumothorax or haemothorax, environments in which the ASOB patient may present and a chest drain is inserted only if the patient is unstable and/or the associated implications. This review, together with CASEVAC is delayed as the procedure may worsen a stable further reading and study (e.g. Intermediate and Advanced patient’s condition and is difficult to manage in transit Life Support courses), will equip an individual with the thereafter. Clearly, the skills to perform the procedure are knowledge to safely manage the ASOB patient. required. However, there are some cases when a chest drain
References 4. O’Driscoll BR, Howard LS, Davison AG. Guideline for emergency oxygen use in adult patients. Thorax 2008; 63(Suppl VI):vi1–vi68. 1. Woollard M, Greaves I. Shortness of breath. Emergency Medicine doi:10.1136/thx.2008.102947 [accessed 20 May 2013]. Journal 2004; 21(3):341-350. doi:10.1136/emj.2004.014878 [accessed 20 May 2013]. 5. Revell M, Porter K, Greaves I. Fluid resuscitation in prehospital trauma care: a consensus view. Emergency Medicine Journal 2002;19(6):494- 2. American Thoracic Society Board of Directors. Dyspnea mechanisms, 498. doi:10.1136/emj.19.6.494 [accessed 20 May 2013]. assessment and management: a consensus statement. Am J Respir and Crit Care Med 1999;159:321-340. 6. Lee C, Revell M, Porter K, Steyn R. The prehospital management of chest injuries: a consensus statement. Faculty of Pre-hospital Care, 3. Battlefield Advanced Trauma Life Support Manual. Joint Service Royal College of Surgeons of Edinburgh. Emergency Medicine Journal Publication 570. 4th Edition; Oct 2008. 2007; 24(3): 220-224. doi:10.1136/emj.2006.043687.
Authors Surgeon Lieutenant V Ahuja MA MBBS DipIMCRCSEd MRCP, Core Trainee 1 ACCS (Anaesthetics/Intensive Care Medicine) Royal Navy
Surgeon Commander D Freshwater MD FRCP, Consultant Physician, Royal Navy
King’s College Hospital, London