WILTIMS #319: Do as I say, unless you do as I do

An ongoing theme for my medical education is learning some of the hypocritical tendencies of doctors. Well, actually that's not quite right. Doctors may do things that they don't want their patients to do, but research has shown that they won't impose their hypocritical recommendations on their patients. For example, obese doctors generally don't counsel patients to lose weight. Doctors who smoke fail to counsel their smoking patients to quit. I don't think this is actually better than just being outright hypocritical.

The example brought up today was in regards to caffeine. Caffeine, like any stimulant, can trigger anxiety disorders. But there's no consistent, evidence-based recommendation for the safe amount of caffeine a day. So the "joke" goes like this:

How many cups of coffee is ok to drink?
One more than your doctor.
How many cups is too much?
Two more than your doctor.

I didn't find it all that funny.

TIL: Panic attacks can mimic many different medical conditions. Since several of those potential conditions can be life-threatening, if someone presents with panic attack symptoms but no history of panic attacks, you must give them the benefit of the doubt and work them up for dangerous conditions like a heart attack or pulmonary embolism. If nothing turns up, especially a few times, then perhaps a psych consult is indicated for treatment of an anxiety or panic disorder. However, epidemiological studies have shown that, if the patient is over ~40 years old and has never had a panic attack, then it's vanishingly unlikely that they are having their first one right now. It's probably worth taking a second look at those possible medical causes.

WILTIMS #164: My thumb hurts

The ever exciting med school flag football season has started up at my school, and after some crazy team-trading drama, we had our first game today. Predictably, I quickly hurt myself by jamming my thumb into someone's hip while reaching for a flag. Jamming is a technical term...

Later in the game as our artificially high score passed 100, I turned to a teammate and, while still rubbing my sore thumb, exclaimed, "Wow, I think we just broke three digits!"

I immediately knew I should have phrased that differently when he looked with a shocked expression down at my hand. Only at a med school flag football game, would he think I was casually commenting on breaking three fingers.

TIL: Red blood cells actually participate in the body's immune response via the complement system. Though they have no nucleus and are generally pretty useless, red blood cells express complement receptors which can bind to antigen fragments and bring them to the liver or spleen, where they are taken up by macrophages for incorporation into the adaptive immune response.

Of course, red blood cells also cause the immune system some problems too; they do not have the ability that most other cells do that tells the immune system they are infected. It's like a bank without a silent alarm and malaria is the crook that has cased the joint. Once inside, malaria is invisible to the immune police. The silent alarm in this case is major histocompatibility complex (MHC) class II, which displays pieces of an infectious agent, alerting the immune system to the infection (and begging for a mercy killing).

Also, it is loosely estimated that there is a 1% decrease in renal function per year after the age of 25. Woohoo, still 98% functioning!

WILTIMS #133: That's not punny

Attendance in class today was as low as the number of classmates with hangovers was high. Last night was our school's spring formal and each neuroscience professor managed to crack a joke about the impaired brains of our absent colleagues.

TIL: There is an area in the brainstem (the parvocellular reticular nucleus) that controls involuntary movements of facial expression. Since this is a separate tract from voluntary movement, it makes possible some peculiar disorders. When such a person is asked to smile, they can't, but if you tell a joke, they will smile normally - assuming the joke is funny. Don't start accusing people of having brain damage just because they don't appreciate your terrible puns.

The Artery of Percheron is an anomalous formation where the diffuse arterioles that normally supply the thalamic midbrain region are consolidated into one small artery. This is dangerous because a small clot can block this vessel and cause a stroke characterized by an immediate loss of consciousness.

Nociceptor is the term for a pain receptor. The prefix comes from the Latin word for "harm," the same word found in the Hippocratic idiom Primum non nocere - "First, do no harm."

The drug naloxone is an opioid receptor antagonist that can block the placebo effect. This is of special interest because it shows that the placebo effect is not purely psychological but somewhat physiological.