Anaesthesia management of transvenous implantation of a single-chamber, rate-adaptive pacemaker in a donkey with high-grade second and third degree atrioventricular block

Abstract

A 17-year-old, domestic, entire, male, miniature donkey with a history of syncope because of sinus bradycardia, high-grade second degree and occasional third degree atrioventricular block was referred for pacemaker implantation under general anaesthesia. After local anaesthesia with topical EMLA cream and subcutaneous mepivacaine infiltration and following tranquilisation with intravenous acepromazine, a temporary pacing catheter was inserted via introducer catheter through the left jugular vein into the right ventricle's apex. After initiation of internal pacing, medetomidine and butorphanol were administered intravenously, followed by ketamine and diazepam. Maintenance of anaesthesia was with isoflurane combined with medetomidine and lidocaine constant-rate infusions. Intramuscular morphine and intravenous medetomidine were administered for recovery. The procedure was uneventful with no anaesthesia-related complications, and manually assisted recovery was smooth. The present report describes the anaesthetic challenges and management of pacemaker implantation under general anaesthesia in a miniature donkey.