[Plasma potassium concentrations during N2O-enflurane anesthesia in patients on chronic hemodialysis]

Plasma potassium concentrations during anesthesia with N2O and enflurane in O2 were measured in 12 patients on chronic hemodialysis (HD) who underwent HD for about 2 hours just before anesthesia. Pre-HD and pre-anesthetic plasma potassium concentrations were 5.0 +/- 0.2 and 4.3 +/- 0.2 mEq.l-1, respectively. The potassium levels decreased slightly following induction of anesthesia, but increased significantly during and after surgery; and at the end of anesthesia the levels were similar to those measured just before HD. None of the patients developed acidosis, hypoxia or hypercapnia. Based on our results, we consider that plasma potassium levels should be measured frequently during surgery in patients who have high potassium levels just before HD and are subjected to HD just before anesthesia, because hyperkalemia may occur.