A review was made four cases for intraoperative or immediate postoperative cardiac arrest which occurred during the period from Jan. 1. 1980 to May 31. 1981 and resulted in death. The probable causes of death were: Case l: inadequate monitoring, hemorrbage, body fluid loss, lengthy operation and sepsis. Case ll: untoward effect of succinylcholine or an underlying cardiac problem. Case lll: cardiac failure due to cardiopulmonary dysfunction caused by kyphoscoliosis. Case lV: peripheral circulatory failure due to massive hemorrhage.