Comparison of two protocols for insulin administration and fasting time in diabetic dogs anaesthetised for phacoemulsification: A prospective clinical trial.

Background: There is a lack of evidence-based guidelines on perioperative insulin administration and fasting time in diabetic dogs. The aim of this study was to compare two protocols with respect to intraoperative changes in blood glucose (BG) concentrations compared to preoperative values.
Methods: Thirty-two dogs were included. Dogs of group AM (n = 15) underwent anaesthesia in the morning after 12 hours fasting and received half their usual insulin dose, while dogs of group PM (n = 17) had surgery in the afternoon after 6 hours fasting and received their usual insulin dose; BG was measured before premedication (baseline), after anaesthetic induction, every 30 minutes throughout surgery, at extubation and after anaesthetic recovery. The occurrence of intraoperative complications was recorded.
Results: There were no differences between groups in perioperative changes in BG over time, and in the proportion of dogs experiencing complications. Common complications were hypotension (53 per cent of dogs in either groups), hyperglycaemia (67 and 65 per cent in groups AM and PM) and hyperkalaemia (20 and 11 per cent in groups AM and PM).
Conclusions: Either protocols may be used in diabetic dogs undergoing anaesthesia. The occurrence of hyperkalaemia in the study population supports routine intraoperative monitoring of blood potassium concentration.
(© 2021 British Veterinary Association.)