Early nutritional inadequacy is associated with psoas muscle deterioration and worse clinical outcomes in critically ill surgical patients

Abstract

PurposeTo explore whether psoas cross sectional area (CSA) and density (Hounsfield Units, HU) are associated with nutritional adequacy and clinical outcomes in surgical intensive care unit patients. Materials and methodsSubjects with at least one CT scan within 72h of ICU admission were included. Demographic, nutritional, radiographic, and outcomes data were collected. Psoas muscle CSA and HU were assessed at the L4–L5 intervertebral disk level. Change (Δ) in CSA and HU overall and per day were calculated. Results140 patients were included. There was no significant correlation between baseline CSA and HU and clinical outcomes. Patients with at least two CT scans (n=65), had a median decrease in CSA of −15% [IQR: −20%, −8%] and decrease in HU of −2% [IQR: −30%, +24%]. Patients with the greatest daily %HU decline received significantly fewer calories/kg and proteins/kg and accumulated greater protein deficits at day 7 and overall. Patients with daily %HU increase had the shortest ICU and hospital LOS and more ventilator-free days in univariate and multivariable analyses. ConclusionsIn this exploratory study, early nutritional deficits were correlated with muscle quality deterioration. Inpatient gain in psoas density, compared to maintenance or loss, is associated with shorter hospital stay.