Abstract
BACKGROUND: Intestinal permeability is an important determinant in intensive care unit patients. Enteral nutrition is vital for nutritional supplementation in critically ill ICU patients. The amount of Enteral nutrition protein and its impact on intestinal barrier permeability and function are challenging issues. Zonulin is a protein that regulates intestinal epithelial cell tight junction permeability and has the potential to be used as a biomarker for assessing the integrity of the intestinal barrier. However, there are few data from studies on intestinal permeability and the effects of enteral feeding of protein on zonulin levels in critically ill patients. This study was conducted to investigate the effect of high-protein enteral nutrition on intestinal permeability in ICU patients. METHODS: Participants were selected from 88 adult patients with critical illness aged 18-65 years who were admitted to the ICU of Hazrat Rasoul Akram Hospital in Tehran. In this randomized controlled clinical trial, patients will be allocated randomly into two groups of 44. The intervention group will receive high-protein (HP) enteral nutrition (1.6 g/kg/day), and the control group will receive conventional-protein (CP) enteral nutrition (1.2 g/kg/day) for 10 days. The primary outcome will be the change in serum Zonulin levels during the intervention period. Zonulin will be measured on days 0, 5, and 10. The SOFA, APACHE II, and mNUTRIC scores will also be assessed. Mortality will be calculated at 30 and 60 days after the intervention. The secondary outcomes will be SOFA score and 30- and 60-day mortality. DISCUSSION: Our study aims to present new evidence about the role of protein in enteral nutrition on intestinal permeability in critically ill patients in the ICU. TRIAL REGISTRATIONS: The clinical trial was registered on December 11, 2024 in the Iranian Registry of Clinical Trials (IRCT) (IRCT20241129063891N1).