A toddler has had several brief episodes of mild perioral cyanosis noticed at day care. The parents see the primary care provider. The exam is normal. The child is admitted for a work-up. The CBC and comprehensive metabolic profile are unremarkable. The chest x-ray is normal. An ECG is normal. An echocardiogram is normal. The EEG is normal. Now what?
I was taught that an uncommon presentation of a common disease is still more common than a common presentation of an uncommon disease. Or simply, odd-looking horses are more common than zebras unless you practice in the savanna. There is a point in any safari at which you have to decide whether you are hunting a zebra or chasing a shadow. Clinical judgment is balancing the risk of missing something preventable that will actually harm the child against the harms of more tests.
The modern hospital has an array of equipment available. They are Greek Sirens calling to us. There is the video EEG room, the MR angiogram, the cardiac cath lab, and an endless list of blood tests. We are not even stopped by the walls of the hospital. We can order a follow-up ambulatory Holter ECG to search for intermittent arrhythmias. But are these Sirens really good medicine? At what point should we simply reassure the parents that the child is fine?
Physicians all worry about missing something. This fear was instilled when we were medical students and reinforced with the stress of residency. With years of experience, all physicians acquire a list of missed diagnoses. But I also have collected a list of times when the diagnostic tests themselves have caused harm, including death. I have a list of cases where nonspecific diagnostic testing has mislabeled a child with an obscure diagnosis that was later proven false, but not before harm was caused. There were patients with Stevens-Johnson syndrome who suffered serious harm from treatments for minor illnesses. Then there were the terrified families who, after extensive testing, became convinced that the child must have some horrible unknown disease because surely we wouldn’t have traumatized the child with all this work-up if there wasn’t really something seriously wrong. Each new test stoked their fear rather than soothed it.
A careful history is still the weapon of choice in the zebra hunt. On a first presentation of mild cyanosis, sepsis is the charging rhinoceros of preventable harm that will run you over if you are too slow to react. But this child has now had several episodes that have occurred: 1. in multiple settings, 2. with no distress, 3. while the child remained playful, and 4. that were self-limited. That history is incompatible with sepsis, so reflexively ordering a blood culture is an illogical choice. The history should be progressively explored using the differential diagnosis and an organ-based systematic approach to guide it. The thoroughness and thoughtfulness I put into the history taking can be key to finding the correct diagnosis. They also are a means of building trust and rapport with the parents. That will be important later if no definitive diagnosis is found.
Unclear and unusual presentations may merit a consult. The cardiologist knows the limits of an echo. Along with the technical expertise comes a new set of eyes and the additional perspective of a second opinion. It is great when a colleague can tell you that he or she too had a case like this years ago that was never solved, but did resolve on its own.
One advantage of being an office-based pediatrician, with an established relationship with a family over several years and a couple other children, is that parents do value and trust your clinical judgment. As a pediatrician, I know the most common product I sell is reassurance. It is not snake oil. There is a bedside manner in selling it. Put a positive spin on all the negative tests. Indicate that you and the parents can be vigilant in watching for new signs. Instruct the parents to bring the child back if the events are distressing for the child, which could justify more invasive testing. Arrange to recheck the child in the office in a week, then a month, then at the next well visit. Parents know that medicine isn’t perfect. Humans deal with fear and uncertainty better by knowing we aren’t facing the future alone. And that is why even with all this technology, I still lay a stethoscope on every child.
Dr. Powell is a pediatric hospitalist and clinical ethics consultant living in St. Louis. Dr. Powell said he had no relevant financial disclosures.