The effect of enteral and parenteral nutrition on quadriceps rectus femoris and vastus intermedius muscle thickness in critically ill intensive care patients

Malnutrition is a major factor that adversely affects the clinical course and prognosis of critically ill patients in intensive care units. It leads to loss of muscle mass and function, potentially resulting in respiratory failure, increased infection risk, and prolonged intensive care units stays. Therefore, determining the most appropriate nutritional support and preserving muscle mass are crucial for reducing both morbidity and mortality in critically ill patients. In this study, we investigated changes in quadriceps rectus femoris and vastus ıntermedius muscle thicknesses in 128 patients expected to remain in the intensive care units for at least seven days. Based on their nutritional approach, patients were divided into four groups: solely enteral, solely parenteral, enteral-to-parenteral, and parenteral-to-enteral. Demographic and clinical data APACHE II score, mechanical ventilation duration, intensive care units length of stay, vasopressor and insulin use, etc.) were recorded on standardized forms. Muscle thickness was measured using bedside ultrasound (ESAOTE LA435® probe) before starting nutrition (Day 0) and on Days 3, 5, 10, and 15 thereafter. Our findings revealed a decrease in quadriceps rectus femoris and vastus ıntermedius muscle thickness over time in all groups, with notably lower muscle thickness in patients receiving enteral-parenteral nutrition, especially on Day 0 and Day 3 (p<0,05). Moreover, the enteral nutrition group exhibited a longer duration of mechanical ventilation and intensive care units stay compared to other groups. In conclusion, both disease severity and nutrition modality play a role in muscle mass depletion among critically ill patients. Hence, implementing a patient-specific and dynamic nutritional strategy is recommended to preserve muscle mass and improve outcomes in critical care settings. Keywords: Enteral nutrition, Parenteral nutrition, Quadriceps Rectus Femoris, Vastus Intermedius