The goal of this randomized controlled trial is to evaluate the role of a high-calorie, high-protein oral nutritional supplement enriched with arginine in the prevention or reduction of post-surgical complications in adult patients undergoing scheduled colorectal surgery who are malnourished or at risk of malnutrition.
The main questions it aims to answer are:
* Does the administration of an arginine-enriched enteral formula decrease the occurrence of post-surgical complications compared to a standard high-protein, high-calorie formula?
* Does the use of an arginine-enriched formula reduce the length of hospital stay and associated healthcare costs?
Researchers will compare a high-protein, high-calorie oral nutritional supplement (ONS) enriched with arginine, omega-3, and nucleotides (Atémpero®) to a standard high-protein, high-calorie ONS without arginine (Diaba plus®) to see if the arginine-enriched formula significantly reduces postoperative complications, such as surgical site infections and dehiscence, as well as the duration of hospital stay.
Participants will:
* Undergo a comprehensive nutritional and clinical assessment, including body composition analysis via bioelectrical impedance and handgrip strength tests.
* Receive individualized oral nutritional supplementation (either the arginine-enriched formula or the standard formula) as part of their preoperative preparation.
* Participate in five follow-up visits (baseline, 24 hours pre-surgery, 24 hours post-surgery, 5 days post-surgery, and 30 days post-surgery) for anthropometric, biochemical, and clinical monitoring.