Vasopressin decreases endogenous catecholamine plasma concentrations during cardiopulmonary resuscitation in pigs.

Abstract

The purpose of this study was to evaluate the effect of vasopressin vs. saline placebo on catecholamine plasma concentrations during cardiopulmonary resuscitation (CPR). Prospective, randomized laboratory investigation by using an established porcine CPR model with instrumentation for measurement of hemodynamic variables, vital organ blood flow, and return of spontaneous circulation. University hospital laboratory. Sixteen domestic pigs. After 15 mins of untreated cardiac arrest and 3 mins of CPR, 16 pigs were randomized to be treated with either 0.8 U/kg vasopressin (n = 8) or placebo (normal saline; n = 8). Arterial epinephrine and norepinephrine plasma concentrations were sampled at prearrest, after 1.5 mins of chest compressions, and at 1.5 mins and 5 mins after drug administration during CPR. In comparison with placebo pigs at 1.5 and 5 mins after drug administration, animals resuscitated with vasopressin had significantly (p < .01) higher mean +/- SEM left ventricular myocardial (131+/-27 vs. 10+/-1 mL x mins(-1) x 100 g(-1) and 62+/-13 vs. 9+/-2 mL x mins(-1) x 100 g(-1)); total cerebral (90+/-8 vs. 14+/-3 mL x mins(-1) x 100 g(-1) and 51+/-4 vs. 12+/-2 mL x mins(-1) x 100 g(-1)); and adrenal gland perfusion (299+/-36 vs. 38+/-7 mL x mins(-1) x 100 g(-1) and 194+/-23 vs. 29+/-5 mL x mins(-1) x 100 g(-1)). Significantly lower mean +/- SEM epinephrine concentrations in the vasopressin pigs compared with the placebo group were measured 1.5 mins and 5 mins after drug administration, (24167+/-7919 vs. 80223+/-19391 pg/mL [p < .01] and 8346+/-1454 vs. 71345+/-10758 pg/mL [p < .01]). Mean +/- SEM norepinephrine plasma concentrations in the vasopressin animals in comparison with placebo were at 1.5 and 5 mins after drug administration significantly lower (41729+/-13918 vs. 82756+/-9904 pg/mL [p = .01] and 10642+/-3193 vs. 62170+/-8797 pg/mL [p < .01]). Administration of vasopressin during CPR resulted in significantly superior vital organ blood flow, but significantly decreased endogenous catecholamine plasma concentrations when compared with placebo.