Perioperative Glucose Metabolism

Future studies using normal saline as diluent would be needed to isolate each drug's specific metabolic contribution. There is a general paucity of clinical studies on perioperative anaesthetic drug effects in pregnant women, making evidence-based management difficult. Observed perioperative changes in blood glucose and insulin resistance will reflect the combined effect of vasopressor plus vehicle rather than the vasopressor pharmacology alone. Because the dextrose vehicle is identical and administered at the same rate in both arms, any vehicle effect is standardised across groups, preserving valid between-group comparison. Perioperative stress triggers abnormal secretion of glucagon and catecholamines, predisposing patients to elevated blood glucose. Using 5% dextrose as drug vehicle means the study cannot fully isolate the pharmacological effect of each vasopressor from the effect of the exogenous glucose infusion.