The Effect of Ketamine or Thiamylal on Succinylcholine-Induced Myoglobinemia Under Halothane Anesthesia in Adults

We studied the effect of intravenous (IV) thiamylal or ketamine on the increases in serum myoglobin, creatine kinase (CK), and potassium induced by succinylcholine under halothane anesthesia.Ninety patients were divided into three groups. In Group O, succinylcholine (1.0 mg/kg) was administered after an inhaled induction of anesthesia with halothane. In Group T, thiamylal (4.0-5.0 mg/kg), and in Group K, ketamine (1.5-2.0 mg/kg) was injected prior to succinylcholine administration. Anesthesia was maintained with halothane, nitrous oxide, and oxygen. Myoglobin increased in Group O at 60 min to 855 ng/mL (median) and CK to 98.6 IU/L. These increases were significantly higher than those of Group T (110 ng/mL and 66.4 IU/L) and Group K (110 ng/mL and 57.0 IU/L). Potassium increased in Group O only. There was no significant difference between Groups T and K for any of the three values. These results indicate that IV thiamylal and ketamine both suppress the increases of myoglobin, CK, and potassium, and that in cases when succinylcholine is used, both drugs can help to avoid myoglobinemia and limit the increases of CK and potassium.(Anesth Analg 1995;81:1015-8)