Prolonged progressive hypermetabolism during COVID-19 hospitalization undetected by common predictive energy equations

Abstract

Background & Aims Indirect calorimetry (IC) is the gold-standard for determining measured resting energy expenditure (mREE) in critical illness. When IC is not available, predicted resting energy expenditure (pREE) equations are commonly utilized, which often inaccurately predict metabolic demands leading to over- or under-feeding. This study aims to longitudinally assess mREE via IC in critically ill patients with SARS-CoV-2 (COVID-19) infection throughout the entirety of, often prolonged, intensive care unit (ICU) stays and compare mREE to commonly utilized pREE equations. Methods This single-center prospective cohort study of 38 mechanically ventilated COVID-19 patients from April 1, 2020 to February 1, 2021. The Q-NRG® Metabolic Monitor was used to obtain IC data. The Harris-Benedict (HB), Mifflin St-Jeor (MSJ), Penn State University (PSU), and weight-based equations from the American Society of Parenteral and Enteral Nutrition – Society of Critical Care Medicine (ASPEN-SCCM) Clinical Guidelines were utilized to assess the accuracy of common pREE equations and their ability to predict hypo/hypermetabolism in COVID-19 ICU patients. Results The IC measures collected revealed a relatively normometabolic or minimally hypermetabolic mREE at 21.3 kcal/kg/d or 110% of predicted by the HB equation over the first week of mechanical ventilation (MV). This progressed to significant and uniquely prolonged hypermetabolism over successive weeks to 28.1 kcal/kg/d or 143% of HB predicted by MV week 3, with hypermetabolism persisting to MV week 7. Obese individuals displayed a more truncated response with significantly lower mREE versus non-obese patients in MV week 1 (19.5±1.0 kcal/kg/d vs 25.1±1.8 kcal/kg/d, respectively; p < 0.01), with little change in weeks 2-3 (19.5±1.5 kcal/kg/d vs 28.0±2.0 kcal/kg/d; p < 0.01). Both ASPEN-SCCM upper range and PSU pREE equations provided close approximations of mREE yet, like all pREE equations, occasionally over- and under-predicted energy needs and typically did not predict late hypermetabolism. Conclusions Study results show a truly unique metabolic response in COVID-19 ICU patients, characterized by significant and prolonged, progressive hypermetabolism peaking at 3 weeks’ post-intubation, persisting for up to 7 weeks in ICU. This pattern was more clearly demonstrated in non-obese versus obese patients. This response is unique and distinct from any previously described model of ICU stress response in its prolonged hypermetabolic nature. This data reaffirms the need for routine, longitudinal IC measures to provide accurate energy targets in COVID-19 ICU patients. The PSU and ASPEN-SCCM equations appear to yield the most reasonable estimation to IC-derived mREE in COVID-19 ICU patients, yet still often over-/under-predict energy needs. These findings provide a practical guide for caloric prescription in COVID-19 ICU patients in the absence of IC.

Dietetic-Led Nutrition Interventions in Patients with COVID-19 during Intensive Care and Ward-Based Rehabilitation: A Single-Center Observational Study

“…This is due to pre-existing chronic disease associated with underlying poor nutritional intake, combined with a further decline due to common COVID-19 symptoms including gastrointestinal dysfunction and loss of taste and smell [ 2 ]. Patients with severe COVID-19 pneumonia exhibit a marked hyperdynamic state with persistent pyrexia leading to hypermetabolism and protein catabolism [ 4 , 5 ]. Furthermore, enteral nutrition (EN) intolerance was reported due to gastrointestinal symptoms, refractory hypoxemia requiring prone positioning, hypotension or shock requiring the use of vasopressors, and the progression of multiple organ failure [ 1 , 6 , 7 , 8 ].…”

Role of Early Enteral Nutrition in Mechanically Ventilated COVID-19 Patients

“…Furthermore, we found COVID-19 patients can demonstrate a persistent hypermetabolic state even out to 7 weeks post ICU admission. This hypermetabolic state often persists considerably beyond the 7–10-day acute hypermetabolic phase described previously in other non–COVID-19 ICU patients ( 13 ).…”

“…Early EN initiation may ultimately prove to have a more significant impact on clinical outcomes in critically ill COVID-19 patients as recent literature reports the hypermetabolism associated with severe COVID-19 maybe more significant and prolonged versus non–COVID-19 ICU patients ( 13 ). Our group recently performed a longitudinal study using indirect calorimetry in mechanically ventilated COVID-19 ICU patients and found over the course of ICU stay COVID-19 patients have a significantly higher measured resting energy expenditure (REE) versus equation-predicted REE ( 13 ). Furthermore, we found COVID-19 patients can demonstrate a persistent hypermetabolic state even out to 7 weeks post ICU admission.…”

Effect of Whey Proteins on Malnutrition and Extubating Time of Critically Ill COVID-19 Patients

“…Kaplan-Meier survival curves for the comparison of the Hazard Ratio between groups were built for the survival analysis. The alpha level of significance was set at 0.05 [21].…”