Nutritional concern is one of the most important issues to be addressed in the perioperative care given to gastrointestinal patients. Not at least, malnutrition may be detrimental and relate to postoperative morbidity. Perioperative nutritional management, integrated with other modern perioperative care policies, allows the establishment of multimodal strategies with an attempt to optimize the patients’ course of disease. The present review evaluates available data regarding pre- and postoperative nutrition, nutritional supplements, including immunonutrition, and their clinical role. It is to be concluded that pre- and postoperative prolonged fasting has no routine role in management. Instead, for example, early postoperative feeding administered perorally or enterally may reduce postoperative complications and length of hospital stay. There are also indications that perioperative immunonutrition may reduce postoperative infectious complications and length of hospital stay, though further studies in this field are needed.

Mechanisms of the acute phase response are discussed including the individual parameters and local changes that take part. Mechanisms involved in failure of the gut barrier are presented and include changes in gut barrier permeability, effects on gut-associated immunocompetent cells, and systemic implications. As examples of HPB disease, mechanisms of the acute phase response and potential ways of intervention in obstructive jaundice and acute pancreatitis are discussed. Nutritional pharmacology and lessons learned from immunomodulation and immunonutrition in critical illness and major abdominal surgery, including upper GI and HPB surgery, are referred to. Overall, immunomodulation represents a potential tool to improve results but requires a thorough mapping of underlying mechanisms in order to achieve individualized treatment or prevention based on patients' specific needs.

The human body's response to surgery is correlated with the extent of tissue damage. The aim of the present study was to, over time, map out parameters concerning inflammation, metabolism, nutrition, breathing function, muscle strength, and well-being in elective colorectal surgery. Eighteen patients were prospectively included: colon resection (n ¼ 9) and rectum resection/amputation (n ¼ 9). Postoperative interleukin 10 (IL-10) rose more in the rectum surgery group on day 0 (P ¼ 0.007) and day 3 (P ¼ 0.025). Furthermore, significant differences between groups were detected regarding albumin, prealbumin, and total iron-binding capacity (TIBC). For albumin and TIBC, this difference was seen even on day 7. C-reactive protein, IL-6, IL-8, glucose, cortisol, insulin, pain, fatigue, nausea, grip strength, and forced expiratory volume in 1 second did not show any differences. No correlation was revealed between measured parameters and postoperative complications. Postoperative levels of IL-10, albumin, prealbumin, and TIBC may be used as determinants of surgical stress after colorectal surgery.