One of the first things they teach you in EMT school is that air should go in and out. So when patients report feeling short of breath, it's time to get serious. Differentiating between the many cases of respiratory distress is far from simple, but using your clinical acumen, being diligent and paying attention to detail can lead you down the path to the right conclusion, facilitating the right treatment plan and doing right for the patient.

First, remember that shortness of breath can be primary or secondary. That is, something might be wrong with the lungs or elsewhere, prompting the lungs to compensate. Primary problems would include asthma, COPD, pulmonary edema, anaphylaxis, pneumonia, pleural effusion and pneumothorax. Secondary problems would include metabolic acidosis, stroke, head trauma, toxicological overdose, sepsis and diabetic ketoacidosis. Figuring out which path to go down requires a careful physical exam, including vital signs, the incident history and patient symptoms.

PHYSICAL EXAM

Focusing on the lungs, auscultation is key. Crackles aren't just crackles, and wheezes aren't just wheezes. Crackles that are coarse, thick and sound "junky" can indicate mucus or infection, while crackles that are fine and "gurgley"-sounding can indicate edema. Wheezes indicate bronchoconstriction, but not necessarily from asthma or COPD. A cardiac wheeze brought on by heart failure is probably more common than we realize, and is often misinterpreted by EMS providers (and emergency physicians, for that matter). Careful, purposeful auscultation is key to understanding what is wrong with your patient and how you can fix it. To get more clues from auscultation, listen intently with your stethoscope on the patient's skin at the left and right apex, hilum and bases.

Air goes in and out, but when is extra respiratory effort required? The inspiratory and expiratory phases of respiration can shed more light on why your patient is in distress. Is your patient working hard to breathe in or trying to force air out? Inspiratory problems are likely caused by compliance pathologies, like pulmonary edema and pneumonia, while expiratory problems are likely caused by resistance pathologies, like asthma and emphysema. Of course, some pathologies are mixed: Anaphylaxis creates mucus that requires more inspiratory effort, as well as bronchoconstriction, which requires increased expiratory pressure. Just staring at the chest to see which phase of respiration is delayed may be a valuable exercise that enlightens your clinical decisions.