When I was in training, blood transfusions for anemia were common. We referred to it as “tanking the patient up,” as if it were a service, such as checking the oil or cleaning the windows. Any patient who was admitted with cardiac ischemia would be discharged with a hemoglobin of 10 g/dL, automatically. It was just good medicine.
Until it wasn’t. The Transfusion Requirements in Clinical Care (TRICC) investigators decided to challenge this practice by conducting a study in which critically ill patients were randomized to different transfusion goals. Half the patients were transfused to a goal of 10 g/dL, and half the patients were transfused to a goal of 7 g/dL.1
What followed was a game-changer. Contrary to the popular wisdom, critically ill patients who were transfused to the higher goal hemoglobin did not have a reduction in mortality. In fact, patients who were younger or less ill fared better if we just left them alone. Subsequent studies tried and failed to find subgroups who routinely benefited from an aggressive transfusion strategy until it became clear: The common wisdom was wrong.
Hence, we come to the cause of the laughter.
When talking to patients, I always describe ischemic digits as akin to having a heart attack of the hand—part of their body is screaming for oxygen. Given this, I was wondering if this patient, with her history of anemia, might benefit from a blood transfusion, to increase her perfusion pressure.
I knew that no such studies existed in scleroderma patients, but I knew someone must have studied this in patients with myocardial ischemia. It has been years since I have practiced internal medicine regularly, so I asked my fellow: Had the findings of the TRICC study been replicated in patients with acute coronary syndromes?
And she laughed at me.
She later explained that she had never heard of the TRICC study referred to by name. The original study was published in the New England Journal of Medicine when she was still in grade school. It was as if she had knocked a glass off a table, and I had referred her to a passage in Principia. No one referred to the study anymore. It was just fact.
If she only knew.
The Truth & Other Myths
I have been alive long enough that I have lived through many versions of the truth. I feel most betrayed by the estrogen story: When I was in medical school, estrogens were thought to be the fountain of youth, the reason why women had fewer heart attacks and strokes than men. Post-menopausal women could continue to experience these benefits if they started to take estrogen supplements, which became an integral part of primary cardiac prophylaxis, as integral as taking an aspirin.
When I was in residency, the story changed. The Women’s Health Initiative demonstrated that estrogens actually increased the rates of heart attacks and strokes among post-menopausal women.2 Because this occurred during my training, I vividly remember the denial that took place around the time the Women’s Health Initiative published its findings. The cohort was skewed. The intervention was wrong.
It was only years later, after much wailing and gnashing of teeth, that we finally became comfortable with the truth: The common wisdom was wrong. My personal takeaway? Thank God my mother never listens to me. When I was in medical school, egged on by my august professors, I harangued her about taking supplemental estrogen. In retrospect, if she had actually started taking Premarin on my say-so, I’m not sure I would have ever forgiven myself.
She also never started taking a baby aspirin, even though everyone knew that it would prevent myocardial infarctions. At least we knew it until a few years ago, when we learned that women with no history of heart disease, like my mother, actually didn’t benefit from taking an aspirin, after all.3
As an aside, I have little patience for the practitioners of revisionist history. I have sat through many lectures that have described why we should have known that estrogens or aspirin or whatever was just snake oil, and if we had looked at the older data in just the right light, the truth would have shown through clearly.
Hogwash. I am old enough that I have borne witness as, again and again, heresy has become scripture and scripture has been dismissed as myth. I can testify that many of the experts who speak with such confidence were saying very different things a decade or two ago, with an equal amount of confidence.