Comparative Study of Perioperative Blood Sugar Levels in Non-Diabetic and Diabetic Patients Using General and Spinal Anaesthesia

Background: Surgical stress and anaesthesia disrupt glucose homeostasis via neuroendocrine activation, causing perioperative hyperglycaemia that is associated with infection, delayed healing, and prolonged hospitalization in patients with and without diabetes. Objective: To compare perioperative blood glucose patterns in diabetic and non-diabetic patients receiving general versus spinal anaesthesia and to examine associations between postoperative hyperglycaemia and early postoperative outcomes. Methods: This comparative observational study included 68 adults undergoing elective surgery at Social Security Teaching Hospital, Lahore over four months. Patients were classified as diabetic (n=34) or non-diabetic (n=34) and received either general anaesthesia (n=34) or spinal anaesthesia (n=34). Blood glucose was measured at standardized perioperative phases (preoperative, intraoperative, postoperative). Two-way ANOVA assessed independent effects of diabetic status and anaesthetic technique on glucose levels; associations between postoperative hyperglycaemia (>200 mg/dL) and outcomes were expressed as odds ratios (OR) with 95% confidence intervals (CI). Results: Mean glucose increased from 128.59±39.94 mg/dL preoperatively to 140.91±41.42 mg/dL intraoperatively (Δ+12.32 mg/dL, 95% CI 8.01–16.63; p