Question Of The Day #82

Shortness of breath, also known as dyspnea, is a common reason for patients to visit the Emergency Department.  Dyspnea is often caused by a pulmonary or cardiovascular condition, but it is important to remember that dyspnea can be due to endocrine conditions, toxicologic conditions, neurologic conditions, hematologic conditions, musculoskeletal conditions, and psychiatric conditions. 

The initial approach to all patients with shortness of breath involves the primary survey, or “ABCs” (Airway, Breathing, Circulation).  This first involves checking the patient for a patent airway.  A simple method to assess the airway is to ask the patient to speak and listen for the voice.  A muffled voice, the presence of stridor, hematemesis, or a lethargic patient are clues that a patent airway may not be present.  Problems with the airway, such as an obstructing foreign body, inflammation (i.e., epiglottitis, anaphylactic shock), or vocal cord dysfunction can certainly cause shortness of breath.  Endotracheal intubation may need to be performed before moving forward.  Breathing is assessed by evaluating the function of the lungs.  Steps include looking at how the patient is breathing (fast or slow), measurement of an SpO2 level, and auscultation of both lungs for wheezing, crackles, rhonchi, or distant or absent sounds.  A low oxygen level should be immediately addressed with supplemental oxygen before moving forward.  The patient’s breathing rate and lung sounds can be very helpful in discovering the diagnosis and guiding treatment.  Lastly, circulation should be assessed.  Check the heart rate, blood pressure, peripheral pulses, skin color and temperature, and evaluate for any sites of hemorrhage.  The presence of hypotension or tachycardia should be addressed appropriately based on the presumed cause.  After the primary assessment (“ABCs”) and initial treatment actions, a more detailed history and physical exam should be conducted. 

Pertinent causes of shortness of breath for the emergency practitioner to know are outlined in the chart below. 

This patient presents to the Emergency department with 1 day of shortness of breath without chest pain, fevers, or a cough.  He has been noncompliant with his home medications for his multiple comorbid conditions.  The exam shows tachypnea, tachycardia, hypertension, a low oxygen level, pulmonary crackles, and peripheral edema.  The chest X-ray shows bilateral pulmonary congestion and infiltrates consistent with pulmonary edema.

Diabetic ketoacidosis (Choice A) can cause shortness of breath, but the severe hypertension, fluid overload on exam, and lack of hyperglycemia make DKA less likely.  Pneumonia (Choice D) can cause shortness of breath, but often has other symptoms like cough, fever, and sometimes chest pain.  It is difficult to rule out an underlying pneumonia in the presence of pulmonary edema by solely looking at the chest X-ray.  The patient’s peripheral edema, severe hypertension, and lack of cough and fever make pneumonia a less likely diagnosis responsible for that patient’s symptoms.  Myocardial infarction (Choice C) often presents with chest pain but can present with only shortness of breath.  A severe myocardial infarction with cardiogenic shock can result in acute fluid overload as seen in this patient, but hypotension would be expected.  A 12-lead EKG is required to more fully evaluate for a myocardial infarction, but the constellation of symptoms this patient has makes congestive heart failure (Choice B) the most likely diagnosis. 

Immediate initial actions for this patient should include placing the patient on a cardiac monitor, obtaining a 12-lead EKG, sitting the patient upright to assist with breathing, and providing supplemental oxygen.  Acute decompensated heart failure should be aggressively treated with Nitroglycerin to lower the blood pressure and stress on the heart (preload).  Noninvasive positive pressure ventilation (NIPPV), such as BIPAP or CPAP, is another crucial initial step to help provide oxygenation, lower the preload, and push the fluid out from the lungs.  IV diuresis to remove fluid from the body and evaluating for the underlying cause are other important steps in acute CHF management.