Odds

It isn't that common to find someone studying English literature at Harvard and medicine at John Hopkins.

I came to learn about Dr. Kevin B. Jones who did so. His book, entitled What Doctors Cannot Tell You, gives me good chance to think about uncertainties in medicine.

I feel more like a gambler than a physician after hearing his stories about the prognosis estimation made by doctors. I don't mean to criticize our prognostic skill. Doctors make a lot of attempts at defining good and bad prognosis. That's what we learn from population studies and statistics. We don't call that gambling; we have a better term "prognosis." The word prognosis comes from the Greek and means knowing ahead of time.

Consider the example of breathing machine in intensive care unit. When a sick patient is being put on a breathing machine that inflates the lungs through a tube placed into the windpipe, he is depending on the machine for life about as much as a human can. Doctors often judge the chance for such patient to recover and wean from mechanical ventilation. In case of poor prognosis, we will decide on terminal extubation. That means removing the tube from the windpipe in anticipation of death. Many of these exceedingly poor prognostic cases will not survive. Most will not, honestly. We can't be hundred percent sure, though. A large study, published in The New England Journal of Medicine, noted 6 out of 166 similar patients surviving to hospital discharge.

Oh no. But that's medicine. We learn medicine from populations of tens and hundreds of thousands (read "epidemiology"). We predict well on populations as large as possible, but we face one patient at a time in real life. We will never be right every single time when we talk about the prognosis of an individual. That's a different story.