Muscle wasting in intensive care patients: Ultrasound observation of the M. quadriceps femoris muscle layer

TLDR

Intensive‑care patients experience significant muscle mass loss, necessitating reliable tools to document this wasting. This pilot study aimed to describe muscle wasting in ICU patients using a two‑fold design of prospective longitudinal and cross‑sectional single‑blind assessments. Seventeen pilot patients were scanned twice (baseline and 28 days later), while 101 additional patients received a single ultrasound measurement after a random ICU stay. Muscle layer thickness of the quadriceps femoris decreased with ICU length of stay, following a logarithmic trend that is steepest in the first 2–3 weeks, confirming ultrasound as a valid, practical tool for routine monitoring of muscle wasting.

Abstract

Patients in intensive care exhibit a high degree of loss of muscle mass. Appropriate instruments are needed to document muscle wasting in these patients. The aim of this pilot study was to describe muscle wasting in patients in the intensive care unit.Two-fold study setting: prospective longitudinal and cross-sectional single-blind.A total of 118 patients in the intensive care unit (length of stay 1-98 days; male:female ratio 88:30; age 55 +/- 17 years) were included in a two-fold study setting.Muscle layer thickness of the M. quadriceps femoris was documented using ultrasound measurement at well-defined points. Seventeen pilot-patients were measured twice; at baseline and after 28 days. In another group of 101 patients, muscle layer thickness was determined once after a random length of stay. The results of both groups were compared and correlated.In both groups, M. quadriceps femoris thickness showed a significant negative correlation with length of stay in the intensive care unit (p < 0.01). Furthermore, muscle wasting in intensive care patients could be described using a logarithmic function.Loss of muscle mass shows a negative correlation with length of stay, and seems to be higher during the first 2-3 weeks of immobilization/intensive care unit stay. Ultrasound is a valid and practical measurement tool for documenting muscle mass (e.g. muscle layer thickness) as part of the daily routine at an intensive care unit.