Hemodynamic effects of external cardiac massage in trauma shock.

The effectiveness of closed chest cardiopulmonary resuscitation (CCCPR) in maintaining cardiac output has been well studied in cardiac arrest. Trauma surgeons most often encounter shock secondary to hypovolemia or cardiac tamponade, and the effectiveness of CCCPR in that setting has not been established. To determine the hemodynamic effects of external massage in profound shock, hypotension was induced in baboons. Pressures obtained with external massage were compared to spontaneous intra-arterial pressures before compression. Although external massage increased systolic pressures in both tamponade and hypovolemia, diastolic pressures were consistently decreased. We conclude that CCCPR does not augment arterial pressure in the clinical situations associated with decreased LVEDV and is unlikely to provide organ perfusion for trauma victims.