Move fast and not break things

In the late 1990s I was studying clinical medicine. The medical education back then split early pre-clinical years (basic sciences) from the later clinical years (patients). The deductive reasoning of the former sometimes jarred with the pattern recognition of the latter. I was on a cardiology ward, examining a patient with heart failure. His heart was failing to pump blood properly, which caused fluid to get backed up, collecting in his ankles and lungs. I knew, from my pre-clinical years, there were two reasons for this: his heart did not pump hard enough, and between beats, did not fill up fast enough. The best practice at the time focused on removing excess fluid (diuretics) and making his heart beat harder (inotropic drugs). I asked the registrar who was teaching us if giving his heart more time to fill up would help. A beta-blocker, perhaps? The answer came quickly: beta-blockers were contraindicated in heart failure. Every generation questions the best practice of the day. This…