Bell Curve

My job is to reassure people that their symptoms are not too far outside the norm, or the “bell curve.” Most patients don’t understand what the bell curve means, but when their illness or injury doesn’t progress as expected, I reassure them that their condition is within one to two standard deviations from the mean.

For example, an 80-year-old woman had been dealing with upper respiratory infection (URI) symptoms for over ten days. She visited the clinic and was started on antibiotics for a possible sinus infection and prednisone for wheezing (i.e., reactive airway disease). The prednisone improved her symptoms, but she reported that her previously prescribed albuterol didn’t seem to help. This piece of history is sometimes revealing because, although the patient may not always remember, someone prescribed that medication in the past, suggesting she likely had similar symptoms before. As a provider, it’s reassuring to know the patient has experienced this condition previously.

Today, however, she came to the ER because her sister suggested she had something stuck in her throat. The patient reasoned that, since she wasn’t coughing anything up, something might be obstructing her airway. This reflects a misunderstanding of her symptoms and how the body works. If she had something stuck in her airway, she would likely have difficulty breathing and possibly stridor—a high-pitched sound indicating an obstruction. An object stuck in the airway would also cause significant discomfort and irritation, which she did not report. Her lungs weren’t filling with mucus from the bottom like a bathtub with a plugged overflow drain. That might make for a funny Bugs Bunny cartoon where Wile E. Coyote drowns after falling off a cliff and sinking to the bottom of a lake with his lungs filling with water, but that’s not how it works. She was eating and drinking normally, which is strong evidence that nothing was stuck in her esophagus either.

Most importantly, she had no specific recollection of something getting stuck. People with an airway obstruction typically report a specific incident, such as a coughing or choking episode. The obstructing object is often something predictable, like a large chunk of unchewed food or something with sharp edges, such as fish, chicken, or goat bones.

Coughs can be productive or non-productive, and this doesn’t always indicate pneumonia, bronchitis, or a specific cause. The cough may stem from something infectious or inflammatory, as in asthma or COPD. Mucus color is mostly meaningless. Ultimately, her URI was slightly outside the norm but not concerning. It didn’t align with her perception of how the illness should progress, but having seen this for many years, it doesn’t worry me. It’s just not in the middle of the bell curve.

What’s odd is that the suggestion of something stuck in her airway was so novel, yet she quickly latched onto it. Had she or her sister met someone with similar symptoms who was diagnosed with an airway obstruction? Unlikely. People want explanations for their symptoms, and to her, this seemed like the simplest one: “I’m coughing, nothing is coming up, so something must be blocking it.” It’s a straightforward but incorrect conclusion.

People choke on food from time to time. Occasionally, something does get stuck in the airway or esophagus, and in rare cases, it can be fatal. Thankfully, such incidents are uncommon.