The relationship between nitrogen balance, muscle loss and clinical outcomes in neuro-critical patients

THE RELATIONSHIP BETWEEN NITROGEN BALANCE, MUSCLE LOSS AND CLINICAL OUTCOMES IN NEURO-CRITICAL PATIENTS Aim and scope: In critically ill patients, the risk of muscle loss is high, particularly in the first 7-10 days, and their body composition significantly changes during hospitalization. It was reported that protein catabolism and acute muscle loss may cause worse clinical outcomes in neuro-critical patients. In this study, it was evaluated that the relationship between nitrogen balances, rectus femoris muscle ultrasound and clinical outcomes was investigated in neurocritical patients. Materials and methods: This study was designed as a clinical prospective observational study in Karadeniz Technical University Faculty of Medicine, Anesthesiology and Reanimation Intensive Care Unit. This study included 44 patients with the neurocritical disease between April 2021 and May 2022. Muscle ultrasound and anthropometric measurements were performed on days 1 and 10, and nitrogen balance was calculated on days 3 and 7 of the intensive care unit. The calorie/protein intake during ten days of hospitalization were recorded, Glaskow Outcome Score and prognosis were evaluated on discharge from the intensive care unit. Univariate and multivariate logistic regression analysis were performed for investigating prognostic factors. Results: The mean age was 47.2±18.1 years and 54.5% of the patients were male. It was found that there was a correlation between the calorie/protein intake and nitrogen balance. The patients divided into two groups: the patients with improved nitrogen balance and the patients without improved nitrogen balance. There was no statistically significant difference in terms of prognosis between these two groups. Increased muscle loss during ten days of hospitalization was founded as predictive factor for poor prognosis in the multivariate logistic regression analysis. Conclusion: There is a correlation between protein/calorie intake and nitrogen balance in neurocritical patients. In addition, the increase in muscle loss affects the prognosis negatively at discharge from the intensive care unit. Randomized controlled clinical studies are required to evaluate medical nutritional therapy according to nitrogen balance for preventing acute muscle loss. Keywords: intensive care, muscle loss, nitrogen balance, nutrition, GOS