Anaesthetising a cat with tetralogy of Fallot for non‐cardiac surgery

Abstract

Tetralogy of Fallot (ToF) is a rare congenital cardiac disease, which has been described in many species, including cats. It often causes cyanosis due to deoxygenated blood entering the systemic circulation. The prognosis of uncorrected ToF is generally poor, but some individuals with mild forms of the disease can survive beyond three years of age. A cat with mild, asymptomatic ToF was anaesthetised for elective ovariectomy. The cat was premedicated intramuscularly with methadone and alfaxalone. Anaesthesia was induced with alfaxalone and midazolam and maintained with sevoflurane in oxygen using mechanical ventilation. Intraoperative analgesia was provided with a constant rate infusion of fentanyl and local anaesthesia. Phenylephrine was infused during anaesthesia to maintain adequate systemic vascular resistance. Mild bradycardia during ovarian tissue handling was treated successfully with atropine. Meloxicam and buprenorphine were used to provide postoperative analgesia. The cat did not experience major complications during anaesthesia and made a full recovery.

Anaesthetic management of a dog with tetralogy of Fallot undergoing placement of a modified Blalock‐Taussig shunt

“…Pekkola et al. cited the same rationale for the use of phenylephrine to increase SVR when anaesthetising a cat with ToF for elective ovariectomy 14 . The judicious use of sevoflurane and the use of the inhalant‐sparing effect of ketamine and lidocaine CRIs in this case limited the decrease in SVR.…”