Cardiovascular function during the postresuscitation phase after cardiac arrest in pigs: a comparison of epinephrine versus vasopressin.
OBJECTIVE
The administration of vasopressin during cardiopulmonary resuscitation (CPR) provides significantly more vital organ blood flow when compared with epinephrine during cardiac arrest in pigs. The effects of this potent vasoconstrictor on postresuscitation cardiovascular function remain unknown. The purpose of this study was to compare the effects of vasopressin and epinephrine on cardiovascular function in the postresuscitation phase after CPR.


METHODS
Prospective, randomized, experimental study.


METHODS
University research laboratory.


METHODS
Domestic pigs, 12 to 14 wks of age.


METHODS
Sixteen pigs were randomly allocated to receive either 0.045 mg/kg of epinephrine or 0.4 U/kg of vasopressin after 4 mins of cardiac arrest.


RESULTS
Hemodynamics, left ventricular contractility, and myocardial blood flow were measured for an interval of 240 mins after successful CPR. Differences between animals treated with epinephrine vs. vasopressin were most pronounced 15 mins after restoration of spontaneous circulation. At this time, mean aortic pressure was 64 +/- 6 (SEM) mm Hg in the epinephrine group and 84 +/- 6 mm Hg (p < .05) in the vasopressin group. Systemic vascular resistance was 1285 +/- 72 dyne.sec/cm5 in the epinephrine group and 2314 +/- 130 dyne.sec/cm5 (p < .001) in the vasopressin group. Cardiac index was 140 +/- 9 mL/min/kg in animals treated with epinephrine and 99 +/- 9 mL/min/kg (p < .01) in animals treated with vasopressin. Myocardial contractility (dp/ dtmax/P) was 52.8 +/- 3.4/sec with epinephrine as compared with 36.3 +/- 2.9 sec-1 (p < .01) with vasopressin. Left ventricular epicardial blood flow was 241 +/- 35 mL/min/100 g with epinephrine and 142 +/- 22 mL/min/100 g (p < .05) with vasopressin. Four hours after CPR, no significant differences were observed between groups.


CONCLUSIONS
In the early postresuscitation phase, vasopressin provided higher systemic blood pressures and there was a reversible depressant effect on myocardial function when compared with epinephrine. Overall cardiovascular function was not irreversibly or critically impaired after the administration of vasopressin in this pig model of cardiac arrest.
Prengel
A W
AW
Department of Anesthesiology and Critical Care Medicine, University of Ulm, Germany.
Lindner
K H
KH
Keller
A
A
Lurie
K G
KG
D000818:Animals; D016887:Cardiopulmonary Resuscitation; D003326:Coronary Circulation / Q000187:drug effects; D004837:Epinephrine / Q000627:therapeutic use*; D006323:Heart Arrest / Q000628:therapy*; D006439:Hemodynamics / Q000187:drug effects*; D008954:Models, Biological; D009200:Myocardial Contraction / Q000187:drug effects*; D013552:Swine; D014667:Vasopressins / Q000627:therapeutic use*
D014667:Vasopressins; D004837:Epinephrine