General intubation anesthesia in primates for experimental otoneurologic surgery

INTRODUCTION
We report our experience in anaesthetic and surgical management of primates (M. fascicularis) in an experimental otoneurosurgical procedure.

MATERIAL & METHODS
The VIII cranial nerve was bilaterally sectioned in a translabyrinthine approach in 21 adult primates. In 14 animals subsequently, a prototype of auditory brainstem implant was placed unilateraly within the brain stem for surface stimulation of cochlear nuclei. Premedication consisted in an intramuscular mixture of ketamine, midazolam and atropine. Surgical procedure was performed under intubated general anaesthesia, after propofol (1.5 mg/kg) administration and maintained with nitrous oxide and halotane.

RESULTS
The mixture of ketamine, midazolam and atropine produced a deep anaesthesia in 4 +/- 1.7 minutes, permitting safe animal handling. Atraumatic nasotracheal intubation without muscle relaxing agents was easily achieved in all animals. Anaesthesia was adequately maintained with nitrous oxide and halotane. Animals did not present any relevant incidents during surgery, and were extubated 10 +/- 2.5 minutes after cessation of gas administration. Post-operatively, no relevant surgical complications occurred.

CONCLUSIONS
We report an anaesthetic technique that provides an optimal restrain and anaesthesia for experimental otoneurosurgical procedures with primates. This technique offers a quick recovery and avoids the use of muscular relaxing agents for intubation, and thus could be safely used in other kind of surgical procedures.

CITA DEL ARTÍCULO  Rev Med Univ Navarra. 2000 Oct-Dec;44(4):12-8