Active compression-decompression cardiopulmonary resuscitation (CPR) is a new innovative basic life-support technique during which the anterior chest wall is actively decompressed by a suction device. CPR techniques were studied in 36 swine to test the hypothesis that active compression-decompression CPR improves coronary perfusion pressure, myocardial blood flow during CPR, and 24-hour survival. After 30 seconds of untreated ventricular fibrillation, CPR was begun and continued for 12.5 minutes by one of the three following methods: (1) active compression-decompression CPR with a suction device modified to include a precision force transducer; (2) standard CPR performed with a force transducer device; and (3) standard manual CPR performed without a force transducer device. CPR-generated coronary perfusion pressure, myocardial blood flow, and the force of compression were measured at 3 and 10 minutes of resuscitation effort. Initial return of spontaneous circulation, 24-hour survival, and trauma scores were also evaluated. Active compression-decompression CPR produced consistently better results than did standard CPR performed with a force transducer, but not better than standard CPR performed manually without a force transducer. The use of a force-measuring device with standard CPR may compromise hemodynamic response and outcome.