Comparison of ketamine-pentobarbital anesthesia and fentanyl-pentobarbital anesthesia for open-heart surgery in minipigs.

The authors analyzed and compared the cardiovascular effects of two anesthetic combinations in minipigs undergoing open-heart surgery and cardiopulmonary bypass. Pigs in group K (n = 15) were anesthetized with low-dose ketamine combined with pentobarbital (5 mg per kg and 20 mg per kg, respectively, for induction; continuous intravenous infusion of 5 mg per kg per h and 10 mg per kg per h, respectively, for maintenance). Pigs in group F (n = 15) were treated with fentanyl and pentobarbital (20 microg per kg and 20 mg per kg, respectively, for induction; continuous intravenous infusion of 20 microg per kg per h and 10 mg per kg per h, respectively, for maintenance). Most pigs remained stable during the surgical procedures and survived for at least one day after surgery; two pigs in group F died during or soon after surgery. Heart rate and mean arterial pressure after bypass were significantly lower in group F than in group K, and pigs in group F required higher doses of inotropic agents to maintain cardiac function. Results suggest that for open-heart surgery and bypass in minipigs, ketamine-pentobarbital anesthesia is associated with more stable cardiovascular conditions than is fentanyl-pentobarbital anesthesia.