Abstract
Introduction and aims The COVID-19 pandemic has placed a significant burden on healthcare systems worldwide, especially in the management of critically ill patients. Accurate assessment of energy expenditure (EE) is crucial for providing optimal nutritional support and improving clinical outcomes in these patients. Indirect calorimetry (IC) is the preferred method for measuring EE, yet its use in critically ill COVID-19 patients has not been extensively documented. This study aims to evaluate EE in critically ill patients with and without COVID-19 to identify differences that may impact nutritional support strategies. Methods We conducted a retrospective observational study at a large tertiary university hospital, focusing on critically ill patients. The study compared calorimetry data between patients with and without COVID-19. Data collected included resting energy expenditure, energy expenditure per kilogram, and respiratory exchange rate quotient using IC. Statistical analysis was conducted using SPSS Version 28, with a significance level set at p < 0.05. Results The study included 95 critically ill patients, comprising 61 non-COVID-19 patients and 34 COVID-19 patients. It was found that COVID-19 patients had significantly lower Simplified Acute Physiology Score (SAPS) II compared to their non-COVID-19 counterparts. Although no significant differences in energy needs over time were detected between the two groups or within the COVID-19 group alone, there was a trend towards lower energy needs in COVID-19 patients. Significant differences were noted in respiratory quotient among COVID-19 patients, particularly between those with and without pulmonary thromboembolism, with the latter group exhibiting lower RQ values. Conclusion Our study suggests that while overall EE may not significantly differ between critically ill COVID-19 and non-COVID-19 patients, there are potential differences in substrate use that underline the necessity for individualized nutritional support. These findings highlight the importance of tailoring nutritional interventions to meet the specific needs of critically ill patients, particularly those with COVID-19.