A total of 160 patients underwent emergency room thoracotomy (ERT) from January 1988 to June 1995. There were 142 male and 18 female patients with ages ranging from 15 months to 72 years old with a mean age of 31 years. Blunt trauma was the mechanism of injury in 11 patients; none of them survived, and they were excluded from further analysis. A total of 149 patients sustained penetrating trauma, 111 patients gunshot wounds, and 38 patients stab wounds. A total of four patients survived to discharge for an overall survival rate of 2.7 per cent. All four were victims of a stab wound and were neurologically intact at the time of discharge. Special interest was placed in classifying patients according to their physiologic status both at the scene and on arrival to the emergency department. Class I, patients with no signs of life; Class II, Agonal--patients in electromechanical dissociation/pulseless electrical activity with no palpable pulse or blood pressure; Class III, Profound Shock--patients with blood pressure less than 60 mm Hg; and Class IV, Mild Shock--patients with blood pressure between 60 and 90 mm Hg. 122 patients (89%) fitted the criteria for Scene Classes I and II. None of these patients improved or responded to prehospital resuscitation to be moved up to Emergency Department Classes III or IV, and all of them died. Of the four survivors, three were in Scene Class III and one was in Scene Class IV. This study confirms a previous report that, overall, ERT has a very low survival rate. ERT should be abandoned in patients sustaining blunt trauma, and should probably be limited to patients sustaining penetrating chest injuries who fall into the physiologic Classes III or IV at the scene.