Pulmonary gas exchange after cardiopulmonary resuscitation with either vasopressin or epinephrine.
OBJECTIVE
It is well established that epinephrine administered during cardiopulmonary resuscitation results in pulmonary gas exchange disturbances. It is uncertain how vasopressin affects gas exchange after cardiopulmonary resuscitation.


METHODS
Prospective, randomized experimental study.


METHODS
Animal research laboratory.


METHODS
Twenty domestic pigs.


METHODS
Animals were subjected to ventricular fibrillation and cardiopulmonary resuscitation by using either vasopressin or epinephrine. Hemodynamic and pulmonary gas exchange (multiple inert gas elimination technique) variables were recorded before cardiopulmonary resuscitation and 10, 30, 60, and 120 mins after return of spontaneous circulation when either epinephrine (control) or vasopressin was used.


RESULTS
At 10 mins after return of spontaneous circulation, blood flow to low V /Q lung units was increased in animals treated with epinephrine (17.8 +/- 6 vs. 2.6 +/- 3%, mean +/- sd, p<.01). Resulting carbon dioxide elimination was impaired in animals treated with epinephrine but not in animals treated with vasopressin (PaCO2, 55 +/- 2 vs. 46 +/- 4 torr, p<.05). Thirty minutes after return of spontaneous circulation, blood flow to lung units with a normal VA /Q ratio was reduced in animals treated with epinephrine (79 +/- 1 vs. 84 +/- 12%, p<.05), resulting in a depressed PaO2 (147 +/- 4 vs. 127 +/- 10 torr, p<.05).


CONCLUSIONS
Vasopressin compared with epinephrine for cardiopulmonary resuscitation resulted in better gas exchange variables in the early postresuscitation phase.
D000818:Animals; D001784:Blood Gas Analysis; D016887:Cardiopulmonary Resuscitation; D004837:Epinephrine / Q000494:pharmacology*; D006439:Hemodynamics / Q000187:drug effects; D011659:Pulmonary Gas Exchange / Q000187:drug effects*; D013552:Swine; D014662:Vasoconstrictor Agents / Q000494:pharmacology*; D014667:Vasopressins / Q000494:pharmacology*; D014693:Ventricular Fibrillation / Q000628:therapy
D014662:Vasoconstrictor Agents; D014667:Vasopressins; D004837:Epinephrine