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 <C> ASOB is caused by an actual or potential deficit in tissue A (c) B C (3). Table 1 lists the differential diagnosis for the oxygenation. This may be caused by inadequate oxygen ASOB medical patient, with associated clinical findings. intake from the environment (airway, breathing or central While this article’s focus is the ASOB patient presenting in nervous system problem), inadequate oxygen delivery by the the absence of trauma, Table 2 shows the additional causes circulation (circulation problem), or impaired oxygen uptake of ASOB that should be considered in trauma, together by the tissues themselves (e.g. sepsis). To compensate, the with management strategies. It is important to highlight patient increases their respiratory rate (RR, tachypnoea that in the initial stages of managing an acutely unwell when RR >16 breaths per minute) and often, heart rate (HR, patient, calling for help is imperative as there is a need for tachycardia when HR >100 beats per minute). If, despite considerable concurrent activity. an elevated RR, the patient is unable to acquire a sufficient Below is a description of the steps one must take in blood oxygenation, the capillary oxygen saturations may fall. assessing and resuscitating an ASOB patient, following As demonstrated by the oxygen dissociation curve, oxygen an A to E approach. Because of the linear nature of this saturations (SaO2) <94% (on air) herald a precipitous article, these are presented alphabetically and sequentially decline. Chronic obstructive pulmonary disease (COPD) is (as in Vertical Resuscitation) but be aware that if manpower an exception to this: however, it is seen very infrequently allows, many of the steps should proceed simultaneously in the military and will not be discussed further here. (Horizontal Resuscitation). J Royal Naval Medical Service 2013, Vol 99.3 93 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