I wave, you wave, we all wave...Moment of admitted medical nerdiness: A woman was in the PACU (post-anesthesia care unit, i.e., the recovery room after surgery) when her labs came back as abnormal. Her potassium was 2.2. Hmm. That's one of the lowest values I've seen in a human who's still breathing. I went to the patient, who was still sleeping off the anesthesia drugs. On her cardiac monitor I noticed a little bump, a spike, and two more bumps. Whoa! She has U-waves! I don't think I've ever personally seen U-waves before. I've learned about them, heard about them...but here's my very own patient with U-waves! The nurse taking care of the patient seemed less than impressed. She probably didn't even know what a U-wave was...which is OK, because it's really more of an academic point. A U-wave on electrical cardiac monitoring is a little bump that represents slight cardiac dysfunction from a very low potassium level. Were the potassium to get any lower, the patient could go into a lethal cardiac dysrhythmia and die. Fortunately for my patient, we replaced her potassium and she's doing fine. Replacing electrolytes: the foundation of the intern's workload. | 
