Anaesthesia for Liver Transplantation in the Pig

Blood gas tensions, acid-base status and cardiovascular function in miniature swine anaesthetized with halothane and methoxyflurane or intravenous metomidate hydrochloride

Göttingen mini-pigs were given atropine and anaesthetized with one of the following drug combinations: 1) azaperone + metomidate, 2) acepromazine + thiopentone for endotracheal intubation, followed by halothane + methoxyflurane in oxygen. Respiration rate, arterial O2 and CO2 tensions, arterial pH, mean arterial blood pressure and heart rate were recorded at 15 min. intervals from 30 to 120 min. after the induction of anaesthesia. The azaperone-metomidate combination, which requires continuous intravenous access, caused a mild respiratory acidosis, but acid-base status was stable, whereas blood pressure and heart rate rose steadily throughout the observation period. The second combination depressed respiratory and cardiovascular function, but the condition of the animals did not deteriorate further during 2 hrs of surgical anaesthesia. Endotracheal intubation for inhalation anaesthesia should, however, be performed after a single injection of metomidate, as thiopentone tended to cause respiratory arrest.