When we understand how things work and how they function in an impaired fashion, then we better remember testing and treatment. In internal medicine, when we understand the physiology and pathophysiology, then we often make better decisions.
Teaching from a physiologic viewpoint can challenge many attending physicians. We believe that investing in this approach has great worth.
Hyponatremia provides an excellent example. When we discuss hyponatremia, we must first understand that it represents a water problem: for some reason we are not excreting enough water. Then we understand how the kidney excretes water. This reasoning leads us to understand the appropriate and inappropriate secretion of ADH. At a higher level, we should understand the stimuli for ADH that can dominate protecting the serum osmolality (stress, pain, volume contraction). Then we should discuss the solute requirement for water excretion and how inadequate solute with fluid ingestion can lead to hyponatremia (beer potomania and tea & toast). Finally, we need to understand the limits of water excretion to understand primary polydipsia. Once we understand the physiology, we understand what tests to order and the principles of treatment.
Then we need to understand the physiology of brain cells and why they swell. This likely explains the risks of correcting the sodium too quickly.
Finally, the physiology helps us understand who has the greatest risk of too rapid correction. Understanding hyponatremia greatly improves when we frame the conversation with basic science.
We can develop a series of such problems. Normal gap acidosis understanding requires a review of physiology. Diuretic pharmacology and use depends on understanding where and how the diuretics work.
Systolic heart failure, home oxygen, the serum ascites albumin gradient, lactic acidosis and the use of biventricular pacing all benefit from a basic science understanding.
We believe that great attending physicians help learners when they explain concepts rather than provide cookbook recipes. Please suggest other examples in the comment section!
db is the nickname for Robert M. Centor, MD, FACP. db stands both for Dr. Bob and da boss. He is an academic general internist at the University of Alabama School of Medicine, and is the Regional Associate Dean for the Huntsville Regional Medical Campus of UASOM. He still makes inpatient rounds over 100 days each year. This post originally appeared at his blog, db's Medical Rants.