Electrolytes, BUN, creatinine: who's at risk?

Electrolytes, BUN, and creatinine are some of the most frequently ordered laboratory tests. The use of these tests in emergency practice has not been studied critically, and few investigations of their use in other disciplines have been performed. A review of the available literature and an analysis of medical problem solving, costs, and complications is presented. Indications based on physiological principles, clinical experience, and limited studies are suggested and areas of future research are outlined.