Assessing Clinical Variables Associated With Femoral Muscle Decay as Measured by Point-of-Care Ultrasound in Critically Ill Children

Objectives

Skeletal muscle wasting is a common occurrence in critical illness, often resulting in intensive care unit (ICU)-acquired weakness. This study aims to identify clinical factors associated with muscle decay in mechanically ventilated critically ill children. Utilizing point-of-care ultrasound, a noninvasive and cost-effective tool, we assess muscle decay through ultrasound of the quadriceps femoris.

Methods

A prospective observational study was conducted in a single-center quaternary-care pediatric intensive care unit at a children's hospital. A convenience sample of 103 sedated and mechanically ventilated patients were enrolled in this study. Ultrasound measurements of quadriceps femoris muscle thickness were taken, and daily muscle decay rates were calculated. Demographic, clinical, and outcome data were analyzed for correlations with muscle decay.

Results

Among the enrolled patients, 67 had repeat measurements. Muscle thickness change aligned with prior studies, with a mean daily change of −1.9% [IQR −0.8, −5.0]. Adequate cumulative caloric intake (>60% of goal) correlated with less muscle decay compared with inadequate intake (−1.8 vs −2.4%, P < .001). Average daily muscle change correlated with both ICU and hospital length of stay (LOS) (r = .328, P = .007 and r = .393, P = .001). No significant correlations emerged between muscle change and mortality, disease severity, fluid balance, early mobilization, steroid exposure, or sedative and paralytic use.

Conclusion

This study demonstrates early and frequent muscle decay in critically ill children, as detected by point-of-care ultrasound. Average daily muscle decay was associated with longer ICU and hospital LOS. Adequate cumulative caloric intake is linked to reduced muscle decay. These findings contribute to understanding muscle wasting in critically ill pediatric patients.