[A case of intraoperative hyperkalemia probably due to preoperative feeding with a liquid enteral formulation]

A 67-year-old man with no remarkable preanesthetic complications underwent esophagectomy. The patient was fed only with a liquid enteral formulation (Ensure Liquid) for 5 days immediately before the operative day. His serum potassium level before Ensure Liquid administration was 4.1 mEq x l(-1). The first blood analysis at 30 min after the initiation of the surgery revealed an increase in serum potassium level (5.9-6.1 mEq x l(-1)) without any conceivable cause during the anesthetic management. A glucose-insulin infusion treatment lowered the serum potassium level to the normal range. The serum potassium level re-increased to 6.4 mEq x l(-1) 4 days after the initiation of jejunal feeding with Ensure Liquid and then returned to the normal range after the termination of Ensure Liquid administration. The patient's perioperative course suggests that the preoperative Ensure Liquid administration is a probable cause of the intraoperative hyperkalemia in this case.