개의 전이도적출술 중 전기지혈에 의해 발생한 삼차신경심장반사 1례

Abstract

A 14 kg, 9-year-old, spayed female, Cocker Spaniel was presented to the Veterinary Medical TeachingHospital of Seoul National University with a history of head tilt and circling. Otitis externa and media were diagnosedby computerized tomography, and total ear canal ablation was performed. In preanesthetic evaluation, systemichypertension and second-degree atrioventricular block were observed, but there was no regurgitation through the heartvalves. Systemic hypertension was managed with amlodipine (0.1 mg/kg, PO, BID) for the anesthesia. The dog waspremedicated with cefazolin (22 mg/kg, IV) and midazolam (0.2 mg/kg, IV). Anesthesia was induced with alfaxalone(2 mg/kg, IV) and maintained with isoflurane and 100% oxygen following intubation. During surgery, vital signs (heartrate, respiratory rate, blood pressure, end tidal carbon dioxide partial pressure and body temperature) were maintainedwithin normal ranges, but bradycardia was observed and corrected with glycopyrrolate (5 ug/kg IV, twice). Duringsubcuticular suture, electrohemostasis was applied at the incision line, which was close to the trigeminal nerve. In notime at all, heart rate dramatically decreased from 110 to 60 beats per minute. No additional treatment was done becausemean blood pressure was maintained above 70 mmHg. The heart rate recovered according to the decrease of end tidalisoflurane concentration and there were no complications associated with the anesthesia and surgery. Sudden bradycardiaafter electrical stimulation around the trigeminal nerve was considered as trigeminocardiac reflex (TCR). It isrecommended to be careful of bradycardia from TCR when electrocautery is used in the craniofacial area during surgery.