Preoperative Nutritional Optimization in Major Surgery: Effects on Postoperative Outcomes and Healing Rates

This randomized controlled trial evaluates the impact of a structured preoperative nutritional optimization protocol on postoperative outcomes in patients undergoing major abdominal surgery. From 2021-2023, 312 malnourished patients (NRS-2002 ≥3) scheduled for gastrectomy, colectomy, or pancreatoduodenectomy were randomized to: 1) Standard Care (SC, n=104), 2) Oral Nutritional Supplementation (ONS, n=104), or 3) Multimodal Optimization (MMO: ONS + immunonutrition + exercise, n=104). The MMO group received 7-14 days of preoperative intervention. Primary outcomes were 30-day complications (Clavien-Dindo ≥II) and anastomotic leak rate. Secondary outcomes included length of stay (LOS), wound healing, and muscle strength. Results demonstrated significantly lower overall complications in MMO (21.2%) vs. ONS (38.5%) and SC (52.9%, p<0.001). Anastomotic leaks decreased in MMO (1.9%) vs. SC (7.7%, p=0.048). MMO shortened LOS by 3.2 days (p<0.001), accelerated wound healing (HR 1.72, 95% CI 1.32-2.24), and preserved handgrip strength (-1.2kg vs. -5.1kg in SC, p<0.001). Preoperative optimization reduced infectious complications by 58% and readmissions by 42%. These findings support protocolized nutritional intervention as a cost-effective strategy to enhance surgical recovery.