Skeletal muscle mass assessment in critically ill patients: method and application

Abstract

The skeletal muscle has a significant role on physical functions, and the assessment of the skeletal muscle is important in critically ill patients. Computed tomography (CT), ultrasound examination, bioelectrical impedance analysis (BIA) device, and biomarkers can all be used to assess skeletal muscle mass. CT is useful for accurately measuring skeletal muscle mass, and the measurement is conducted at the third lumbar vertebra level as the gold standard. However, the assessment using CT is done retrospectively because CT involves radiation exposure and requires patients to be transported to the examination room. On the other hand, ultrasound and BIA are noninvasive and can be used at the bedside to assess longitudinal skeletal muscle mass. However, accurate assessment requires knowledge and skills. Assessments using BIA should be carefully interpreted because critically ill patients are under dynamic fluid change and edema. Furthermore, various biomarkers for the assessment of skeletal muscle mass have been recently reported. Appropriate skeletal muscle assessment will contribute to the nutrition and rehabilitation intervention of critically ill patients so that they can return to society.