This mini-lecture with Dr. Amal Mattu from Essentials of EM is gold for diagnosing severe hypokalemia (usually less than 3) on EKG. We all know about U-waves, but these are non-specific for hypokalemia and generally not that helpful. But as the potassium drops significantly below normal levels, the T-waves begin to invert and the U-waves grow taller causing a “Reverse-Wellen’s” wave, or as he coined after his children, “NikEleKam Ts.” With this knowledge, you can give Magnesium before the labs result and prepare to replete the potassium much sooner.
Severe Hypokalemia on EKG with Amal Mattu
Severe hypokalemia on the EKG.