Comparing low flow and high flow isoflurane anaesthesia using V-gel® supraglottic airway device in cats

The aim of this study was to determine the clinical utility of low-flow and high-flow anesthesia in cats undergoing isoflurane general anesthesia and using V-Gel® supraglottic airway device (SGAD). The study material consisted of 16 cats brought to Surgery Clinic of Burdur Mehmet Akif Ersoy University, Faculty of Veterinary Medicine with different complaints. Fourteen of the cats were male and 2 was female. The weight of cats for low flow anesthesia (LFA) and high flow anesthesia (HFA), ranged from 2,55-5 kg (mean, 3,43±0,29 kg) and 3,1-5 kg (mean, 4,04±0,21 kg) respectively. Sixteen cats were randomly divided into two equal groups (LFA group n=8, HFA group n=8). All cats received 1,1 mg/kg acepromazine orally for tranquilization. After 20 minutes, 4 mg/kg propofol was administered intravenously. The LFA group was initially given 0,8 L of fresh gas flow and the vaporizer set to 3% and administered isoflurane. The flow was then reduced to 0,2 L and the end tidal isoflurane MAC concentration was maintained at 1,6-1,8. The HFA group was initially given 0,8 L of fresh gas flow and the vaporizer set to 3% and administered isoflurane. The end tidal isoflurane MAC concentration was then maintained at 1,6-1,8 without changing the fresh gas flow. Butorphanol was administered subcutaneously 15 minutes before the end of the surgical procedure to produce analgesia. With the final suture, the fresh gas flow in the LFA group was increased to 0,8 L and the vaporizer was switched off. Hemodynamic parameters, venous blood gas (before anesthesia, during anesthesia, spontaneous breathing), dynamic compliance, extubation time, isoflurane and oxygen consumption were evaluated. The mean amount of isoflurane and oxygen consumption in the LFA group was 3,13±0,64 ml and 25,88±2,25 L respectively. The mean amount of isoflurane and oxygen consumption in the HFA group was 9,38±0,92 ml and 49,25±2,14 L respectively. According to the results of the study, hemodynamic parameters, venous blood gas results, dynamic compliance and extubation times were similar for both groups. It was concluded that LFA using V-Gel® with the use of apporiate techniques and devices, close monitoring of lactate levels for isofluran mainteance can be applied safely in cats. Key words: Cat, High flow, İsoflurane, Low flow, V-Gel®