CARDIOPULMONARY EFFECTS OF PROPOFOL AND A MEDETOMIDINE-MIDAZOLAM-KETAMINE COMBINATION IN MALLARD DUCKS

Objective-To compare safety of propofol with a medetomidine-midazolam- ketamine (MMK) combination as an anesthetic agent in mallard ducks. An imals-12 healthy adult female mallard ducks. Procedure-Each duck was a nesthetized twice in a crossover study design with 5 days between rand omized treatments. Ducks were given medetomidine (50 mu g), midazolam (2 mg), and ketamine (10 mg) in combination, IV, or propofol (10 mg, I V, followed by 1- to 4-mg boluses). Systolic, diastolic, and mean arte rial pressures, heart and respiratory rates, and esophageal temperatur e were recorded before anesthesia and every 5 minutes after induction for 30 minutes, and at 5 minutes after reversal with atipamezole (250 mu g) and flumazenil (25 mu g; MMK group) or last bolus (propofol grou p). Arterial blood samples from 8 ducks were collected before anesthes ia, 5, 10, 15, 30 minutes after induction, and after reversal or last bolus. Results-8 ducks survived the MMK anesthesia; 1 duck died and 3 ducks required resuscitation to prevent death. All ducks survived prop ofol anesthesia, Ducks anesthetized with either anesthetic agent had a significant increase in arterial carbon dioxide tension and decrease in arterial oxygen tension, arterial pH, and esophageal temperature. D ucks given MMK had a decrease in mean arterial pressure and respirator y rate, whereas ducks given propofol had an increase in respiratory ra te. Rapid reversal of the effects of MMK was achieved with atipamezole and flumazenil. All physiologic variables, except esophageal temperat ure in the propofol group, returned to approximate baseline values aft er reversal or last bolus. Conclusions-The MMK combination is unsafe f or use in ducks. Ducks can be anesthetized safely with propofol but sh ould be monitored and ventilated artificially.