Perioperative fasting remains a common clinical practice in surgical patients to prevent the development of postoperative anesthesia- and surgical-related complications. Clinical observational studies indicated that the combination catabolic effects resulted from prolonged perioperative fasting and profound surgical stress are likely to induce extensive protein catabolism, muscle breakdown and impaired glycemic control during postoperative phase, leading to the development of severe complications. Furthermore, prolonged gastrointestinal fasting is associated with microbial translocation that deteriorates the early recovery after surgery. This clinical trial anticipates in determining the beneficial effect of intraoperative feeding to improve intraoperative hemodynamics and enhance postoperative recovery due to attenuation of systemic catabolism and improvement of insulin sensitivity to glycemic control.

Perioperative fasting remains a common clinical practice in surgical patients, aiming to prevent pulmonary aspiration during anesthesia induction, improve bowel preparation, and ameliorate the development of postoperative nausea/vomiting or other surgical-related complications. Major head-and-neck tumor excision and reconstruction surgery is one of the most time-consuming surgeries that usually takes more than 12 h to complete. In addition to the preoperative fasting and postoperative recovery time periods, most of these patients will be fasted for more than 24-36 h before they are fed via nasogastric tubes in the postoperative care units. The combination catabolic effects resulted from prolonged perioperative fasting and profound surgical stress are likely to induce extensive protein catabolism, muscle breakdown and impaired glycemic control during postoperative phase. These catabolic responses may lead to the development of post-operative surgical site infection, delayed wound healing, re-intervention, cardiac arrest, and death in diabetic and non-diabetic patients. Furthermore, prolonged gastrointestinal fasting is associated with dehydration, perturbed gut integrity/permeability (leaky gut) and microbial (bacterial) translocation that deteriorates the early recovery after reconstruction surgery. The aim of this clinical trial is to test the effect of intraoperative feeding in patients receiving head-and-neck tumor excision and reconstruction surgery, and anticipate that reduction of perioperative fasting time may improve intraoperative hemodynamics and enhance postoperative recovery due to attenuation of systemic catabolism and improvement of insulin sensitivity to glycemic control.

This single-center clinical trial will be undertaken in a randomized, double-blind, placebo-controlled fashion, in which patients with advanced head-and-neck tumor who are scheduled for extended tumor resection and free-flap reconstruction will be randomly assigned to receive control (no intraoperative feeding) or intraoperative feeding group. Feeding via the nasogastric (NG) tube will start after the establishment of tracheostomy and completion of tumor resection at fusion rate of 10-30 ml/h (feeding diet 1 Kcal/ml and 0.04 g protein/ml). This trial anticipates in detecting differences in intraoperative hemodynamic stability and development of major postoperative complications, including delayed wound healing, surgical site infections and insulin-resistant hyperglycemia between controls and intraoperative feeding group. The outcomes of this clinical trial may provide fundamental evidence for vigorous enteric nutrition and energy support during prolonged high surgical stress operation.

Inclusion Criteria:

• Advanced head-and-neck cancer
• Requires radical resection, tracheostomy and free flap reconstruction surgery

Exclusion Criteria:

• Anticipated total operation time < 6h
• Emergency operation
• Bowel obstruction
• Starts nasogastric feeding before operation

Participants: patients will receive general anesthesia before intervention Care providers: surgeons will be masked of the treatment group during operation