INS and diabetes mellitus: PrIG = Pre-intervention group; PoIG = Post-intervention group; M = Male; F = Female; NA = Non-diabetic; T1DM (I) = Type 1 diabetes mellitus on insulin therapy; T2DM (D) = Type 2 diabetes mellitus on diet control; T2DM (O) = Type 2 diabetes mellitus on oral hypoglycaemic medication; T2DM (I) = Type 2 diabetes mellitus on insulin therapy; GA = General anaesthesia; MAC = Monitored anaesthesia care, i.e., local anaesthesia with sedation; ASA: American Society of Anaesthesiologists