ABSTRACT
Optimal nutritional status, both pry- and postoperatively, is a key factor in reducing perioperative complications and improving surgical outcomes. Appreciation of the importance of nutritional status is becoming more widespread within the healthcare profession and many tools have been developed to help identify poor nutritional status. The constant need for glucose by metabolically active tissues in the body, such as the brain, red and white blood cells and the renal medulla, necessitates homeostasis of blood glucose levels even during periods of fasting. The metabolic response to surgery is affected not only by the induced fasting period but also by the phenomenon of insulin resistance, which has been described in surgery and in other similar stresses, including trauma and burn injuries. Intravenous fluid replacement may be necessary in conditions of gastrointestinal absorptive impairment or large fluid losses that cannot be quickly replaced via the enteral route.
