Occam’s razor is a well-known logical principle often applied in medicine. It states that the simplest explanation for a complaint or symptom is usually the correct one. Most of the time, Occam’s razor serves the diagnostician well, but when the actual problem is complex or unexpected, patients can be sent down expensive and even life-threatening diagnostic rabbit holes.
A friend of mine is an 80-pack-a-year smoker. He was complaining of shortness of breath, worsening over a couple of months, and his primary care physician sent him to a pulmonologist. The assumption was that the shortness of breath was related to COPD from his chronic smoking — and that indeed would have been the most likely explanation.
When my friend arrived at the pulmonologist — it was assumed that the primary care physician had correctly triaged him — he was subjected to the usual battery of pulmonary function tests (PFTs) and was given an inhaler prescription due to poor test performance. A month later he returned to explain that he did not feel better. He was reassured that it would take a year for the inhalers to make a difference in his PFTs. He returned again a couple of months later for a prescription refill, ashen-appearing and exhausted.
At that point the pulmonologist thought to do a pulmonary stress test with EKG, and low and behold, my friend was in atrial fibrillation (AF). His shortness of breath was related to his heart not pumping oxygenated blood around successfully, not any COPD-related issues. Because the AF had been going on for several months, it was likely that his atria had developed a clot inside them from low blood flow, and he was at risk for imminent stroke (and a treadmill test was certainly a dangerous proposition).
The pulomonologist called 911 and my friend was transferred to a local hospital for anticoagulation and cardioversion. He did in fact have a clot in his left atrium, and a small embolus dislodged itself and traveled to his right finger tip — which went numb (but recovered 6 months later). Fortunately the clot dissolved on IV heparin and he responded to the chemical cardioversion. My friend hasn’t had another episode of AF since.
It’s extremely lucky that my friend’s AF was diagnosed before he’d had a stroke or other life-threatening sequelae. It’s amazing that his lungs are in fairly good shape considering his years of smoking. The correct diagnosis was postponed by a belief in Occam’s razor. As Jerome Groupman suggests, we should always ask ourselves: “What else could this be?” when approaching a new patient. Just because one of our peers says there’s a pulmonary problem doesn’t mean there is one.
Let’s continue to approach each patient with a fresh eye, and remember to keep broad differential diagnoses in mind. Doing that without resorting to excessive testing or expensive defensive medicine is one of our greatest challenges.