In a prospective study of the complications of cardiac resuscitation, 705 cases were autopsied to identify the cause of death and the pathologic findings attributable to cardiac resuscitation. Thoracic complications were observed in 42.7 percent of the cases. A total of 31.6 percent had rib fractures, 21.1 percent had sternal fractures, and 18.3 percent were reported as having anterior mediastinal hemorrhage; 20.4 percent of the cases had an upper airway complication. Abdominal visceral complications were noted in 30.8 percent of the cases, and pulmonary complications occurred in 13 percent of the resuscitation population. Life-threatening complications, such as heart and great vessel injuries, occurred in less than .5 percent of the cases.