Survival with full neurologic recovery and no cerebral pathology after prolonged cardiopulmonary resuscitation with vasopressin in pigs

OBJECTIVES We sought to determine the effects of vasopressin and saline pla cebo in comparison with epinephrine on neurologic recovery and possible cer ebral pathology in an established porcine model of prolonged cardiopulmonar y resuscitation (CPR). BACKGROUND It is unknown whether increased cerebral: blood flow during CPR with vasopressin is beneficial with regard to neurologic recovery or detrim ental owing to complications such as cerebral edema after return of spontan eous circulation. METHODS After 4 min of cardiac arrest, followed by 3 min of basic life supp ort CPR, 17 animals were randomly assigned to receive every 5 min either va sopressin (0.4, 0.4 and 0.8 U/kg; n = 6), epinephrine (45, 45 and 200 mu g/ kg; n = 6) or saline placebo (n = 5). The mean value +/- SEM of aortic dias tolic pressure was significantly (p < 0.05) higher 90 s after each of three vasopressin versus epinephrine versus saline placebo injections (60 +/- 3 vs. 45 +/- 3 vs. 29 +/- 2 mm Hg; 49 +/- 5 vs. 27 +/- 3 vs. 23 +/- 1 mm Hg; and 50 +/- 6 vs. 21 +/- 3 vs. 16 +/- 3 mm Hg, respectively). After 22 min o f cardiac arrest, including 18 min of CPR, defibrillation was attempted to achieve return of spontaneous circulation. RESULTS All the pigs that received epinephrine and saline placebo died, whe reas all pigs on vasopressin survived (p < 0.05). Neurologic evaluation 24 h after successful resuscitation revealed only an unsteady gait in all vaso pressin-treated animals; after 96 h, magnetic resonance imaging revealed no cerebral pathology. CONCLUSIONS During prolonged CPR, repeated vasopressin administration, but not epinephrine or saline placebo, ensured long-term survival with full neu rologic recovery and no cerebral pathology in this porcine CPR model. (J Am Coll Cardiol 2000;35:527-33) (C) 2000 by the American College of Cardiolog y.