Effects of spinal anaesthesia on metabolic processes

A study conducted at P.G.I., Chandigarh to find out the effect of spinal anaesthesia on arterial blood gases, blood glucose, and pyruvate-lactate during spinal anaesthesia. All patients received night sedation of oral diazepam in dose of 0.2 mg/kg body weight. No narcotic/antisialogogue premedication was given to any patient. All patients received spinal anaesthesia with 5% lignocaine (hyperbaric), in lateral position. All patients received normal saline intravenously as a maintenance fluid. Blood samples for the measurement of blood pyruvate, lactate levels and arterial blood gas analysis were collected preoperatively, 10 minutes after the administration of spinal anaesthesia after fixation of drug, and half hour after the end of operative procedure. Even though there was continued rise in blood sugar levels intraoperatively, which persisted in postoperative period, the values were within normal clinical range. Blood lactate levels and blood pyruvate levels remained unchanged. Hypocapnoea observed intra-operatively in our report is attributed to hyperventilation. There was 12.44% fall in bicarbonate level. (P > .001) which even though statistically significant did not alter the pH. We conclude that spinal anaesthesia up to T8 level does not affect the metabolic processes.