Intravenous alanyl-L-glutamine balances glucose-insulin homeostasis and facilitates recovery in patients undergoing colonic resection: a randomised controlled trial.

BACKGROUND: Glucose and insulin homeostasis are altered in patients undergoing gastro-intestinal tumour resection and affect the postsurgical outcomes. OBJECTIVES: To evaluate the impact of dipeptide alanyl-L-glutamine supplementation on glucose-insulin homeostasis, inflammatory mediators and surgical recovery in patients undergoing colonic cancer resection. DESIGN: A randomised controlled trial. SETTING: Southeast University Affiliated Zhongda Hospital, China, from January 2011 to May 2011. PARTICIPANTS: Patients aged 35 to 75 years, ASA physical status I-II, scheduled for elective colon cancer resection. INTERVENTIONS: Sixty patients were randomised into one of the three groups and received 22.4 ml kg of physiological saline, a 8.5% 18AA-II solution (a compound amino acid) or glutamine 0.5 g kg, given 24 h before and 1 h after the start of the surgical procedure. PRIMARY OUTCOMES MEASURE: Insulin resistance index and insulin sensitivity check index. Secondary outcomes included blood glucose, insulin, tumour necrosis factor-alpha (TNF-α) and free fatty acid measured at 24 h before surgery (T1), 30 min before anaesthesia (T2), 2.5 h after the beginning of surgery (T3), and 1 h (T4) and 24 h (T5) after the end of surgery. The time of first passage of wind and the length of hospital stay were recorded. RESULTS: Intraoperative and postoperative insulin resistance or calculated insulin sensitivity were worse in the physiological saline and 18AA-II treated patients compared with those treated with glutamine (P < 0.05). Blood glucose increased intraoperatively and postoperatively in all three groups compared with baselines (P < 0.05), but glutamine attentuated the peak level of blood glucose (P < 0.05). Glutamine reduced the intraoperative and postoperative concentrations of TNF-α and free fatty acid, (P < 0.05), and shortened the time to the first passage of wind after surgery and the length of hospital stay (P < 0.05). CONCLUSION: Intravenous supplementation with glutamine balances glucose-insulin homeostasis and facilitates recovery in patients undergoing colon cancer resection.