Stroke volumes generated by precordial compression during cardiac resuscitation

Objectives To quantitate stroke volumes generated by precordial compression during cardiopulmonary resuscitation and to determine their relationship to coronary perfusion pressure and the success of resuscitation. Design Prospective, observational animal study. Setting Medical research laboratory in a university-affiliated research and educational foundation. Subjects Domestic pigs. Interventions Ventricular fibrillation was electrically induced in 25 anesthetized male domestic pigs. After an interval of 7 mins, electrical defibrillation was attempted. Failing to reverse ventricular fibrillation in each instance, precordial compression was begun coincident with mechanical ventilation. Measurements and main results Stroke volumes were computed from differences between diastolic and systolic areas of the left ventricle by utilizing transesophageal echocardiography. Both stroke volumes and coronary perfusion pressure were consistently greater in successfully resuscitated animals. Progressive decreases in stroke volumes during precordial compression were predictive of unsuccessful resuscitation. A linear correlation between stroke volume and coronary perfusion pressure (r =.70) was documented. Conclusion These observations support the concept that stroke volumes generated by precordial compression are quantitatively related to the coronary perfusion pressure and to the success of cardiopulmonary resuscitation.