Approach to dyspnea: Clinical sciences

Acute dyspnea is the sensation of difficult or uncomfortable breathing that develops over hours to days. Dyspnea is a common symptom with a wide range of causes including respiratory, cardiovascular, metabolic, neuromuscular, and neurologic conditions. Many causes of acute dyspnea are life-threatening, so it is important to have a systematic approach to evaluating these patients.

When approaching a patient with dyspnea, first you should perform an ABCDE assessment, to determine if your patient is unstable or stable. If they are unstable, first check for alarm signs and symptoms! Check for upper airway obstruction by auscultating for stridor, a high-pitched breathing sound, and by directly examining the airway for oropharyngeal swelling or the presence of a foreign body.

If the airway is clear, evaluate the patient’s breathing by assessing respiratory rate and oxygen saturation. A respiratory rate less than 10 or greater than 20 breaths per minute, or oxygen saturation less than 90% requires acute management.

You should also look for red flag features that signal impending respiratory failure such as confusion, inability to speak in complete sentences, and the use of accessory respiratory muscles, such as the scalenes and intercostals.

In this case, stabilize the airway, breathing, and circulation, which may require removing any airway obstruction, endotracheal intubation and mechanical ventilation. Some patients might require supplemental oxygen only, but, in both cases, don’t forget to obtain IV access and put your patient on continuous vital sign monitoring.

Now, here’s a high-yield fact to keep in mind! Causes of acute airway obstruction, that might present with stridor, include anaphylaxis, epiglottitis, and the presence of a foreign body.