Neuromuscular blockade as part of an anaesthetic protocol for cataract surgery in an alpaca

A six-month-old alpaca was presented to the veterinary teaching hospital of the University of Liège (Belgium) with a bilateral cataract. A decision was made to perform bilateral cataract surgery after an ocular ultrasound and electroretinogram were performed to assess the posterior segment and retinal function, respectively. As a premedication, the alpaca received xylazine, butorphanol and midazolam intramuscularly. Anaesthesia was induced subsequently with ketamine and midazolam intravenously and maintained with isoflurane on oxygen/air mixture. The alpaca was mechanically ventilated during surgery. Neuromuscular blockade was induced and maintained with cis-atracurium intravenously. The dose of cis-atracurium was permanently adapted using a peripheral nerve stimulator. This case report brings new knowledge regarding the use and dosage of cis-atracurium in alpacas.