Ultrasonographic assessment of the muscle mass of the rectus femoris in mechanically ventilated patients at intensive care unit discharge is associated with deterioration of functional status at hospital discharge: a prospective cohort study.

Abstract

Objective: To verify whether the rectus femoris muscle mass in mechanically ventilated patients assessed by ultrasonography at intensive care unit discharge is associated with functional status at hospital discharge.

Methods: This cohort study was conducted at a tertiary hospital in Brazil between August 2019 and November 2020. We included patients over 18 years who were previously independent (Barthel index > 60) and underwent mechanical ventilation for at least 48 hours within 96 hours of admission. Ultrasonographic measurements of the rectus femoris cross-sectional area and right quadriceps thickness were performed upon enrollment, five days after enrollment, and at intensive care unit discharge. The primary outcome was assessing functional capacity via the Barthel index at hospital discharge.

Results: Of the 78 patients included, 35 had assessable primary outcomes. Twenty (57.1%) patients were considered functionally dependent (Barthel index < 60). The Barthel index at hospital discharge was correlated with the cross-sectional area (r = 0.53; p = 0.001) and quadriceps thickness (r = 0.43; p = 0.01) at intensive care unit discharge. Multiple linear regression analysis revealed that the cross-sectional area at intensive care unit discharge was independently associated with the Barthel index.

Conclusion: We found that muscle mass assessed by cross-sectional area ultrasonography at intensive care unit discharge was significantly correlated with functional capacity at hospital discharge.