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Thigh Ultrasound Monitoring Identifies Decreases in Quadriceps Femoris Thickness as a Frequent Observation in
Frederic V Valla1, David K Young, Muriel Rabilloud
11Pediatric Intensive Care, Hôpital Femme Mère Enfant, Hospices Civils de Lyon, Lyon, France. 2Physiotherapy Department, Addenbrooke's Hospital, Cambridge, United Kingdom. 3Hospices Civils de Lyon, Service de Biostatistique et Bioinformatique, Lyon, France. 4Université Lyon 1, Villeurbanne, France. 5CNRS, UMR 5558, Laboratoire de Biométrie et Biologie Evolutive, Equipe Biostatistique-Santé, Villeurbanne, France. 6Paediatric Intensive Care Unit, Addenbrooke's Hospital, Cambridge, United Kingdom. 7Pediatric Neurology and Rehabilitation Unit, Hôpital Femme Mere Enfant, Hospices Civils de Lyon, Lyon, France. 8EPICIME-CIC 1407 de Lyon, Inserm, Service de Pharmacologie Clinique, CHU-Lyon, Bron, France. 9Department Paediatrics, Imperial College London, St. Mary's Campus, London, United Kingdom. 10Pediatric Intensive Care Unit, Réanimation Pédiatrique, Hôpital Mère enfants, CHU de Nantes, Nantes cedex, France. 11Hôpital Femme Mère Enfant, Hospices Civils de Lyon, Lyon, France. 12Department of Paediatrics, University of Cambridge, Cambridge, United Kingdom.
Insights
Pediatric intensive care unit (PICU) patients experience rapid muscle wasting, measurable by quadriceps femoris thickness using ultrasound. This reliable technique can monitor muscle loss and guide interventions.
Area of Science:
- Pediatric critical care medicine
- Diagnostic imaging
- Muscle physiology
Background:
- Critically ill adults experience significant muscle wasting, leading to poorer outcomes.
- Muscle wasting in critically ill children is poorly understood due to a lack of objective assessment methods.
- Previous single-measurement techniques for quadriceps femoris thickness lacked reproducibility.
Purpose of the Study:
- To evaluate the reproducibility of bedside ultrasound measurements of quadriceps femoris thickness in mechanically ventilated children.
- To determine if averaged repeated measurements can reliably detect changes in muscle thickness.
- To establish quadriceps femoris thickness decline as a potential marker for muscle wasting in pediatric intensive care unit (PICU) patients.
Main Methods:
- Prospective, observational study conducted in two PICUs.
- Bedside ultrasound was used to measure quadriceps femoris anterior thickness in mechanically ventilated children aged 15 years and younger.
- Measurements were repeated, and the average of four readings was recorded. Measurement sites were marked for consistency.
- Intra- and interoperator reliability were assessed. Serial measurements were taken in a subset of children until extubation.
Main Results:
- Seventy-three children were enrolled for reliability assessments.
- Intraoperator repeatability showed a mean relative difference of 0.36% ± 2.5%.
- Interoperator reproducibility yielded an intraclass correlation coefficient of 0.998.
- In 17 children with prolonged PICU stays, quadriceps femoris thickness decreased significantly by day 5 (9.8%) and by the last measurement (13.3%).
Conclusions:
- Decreased quadriceps femoris thickness, a surrogate for muscle mass, is an early, frequent, and significant finding in critically ill children.
- Bedside ultrasonography of the quadriceps femoris is a reliable method for monitoring muscle wasting in the PICU.
- This technique holds potential for guiding future rehabilitation and nutritional interventions in pediatric critical care.
Objectives:
Significant muscle wasting develops in critically ill adults, with subsequent worse outcomes. In the pediatric setting, occurrence and effects of muscle wasting are undescribed; this is in part due to a lack of validated, objective methods for assessing muscle wasting. A single measurement of quadriceps femoris thickness has failed to show consistent reproducibility. We hypothesized that averaging repeated measurements could afford good reproducibility to allow for quadriceps femoris thickness decline detection and monitoring.
Design:
A prospective bedside observational study.
Setting:
Two PICUs.
Patients:
Mechanically ventilated critically ill children were 15 years and younger.
Interventions:
Transverse and longitudinal axis measurements of quadriceps femoris anterior thickness were undertaken using bedside ultrasound. The average of four measurement values was recorded. The location of measurement was marked for consistency within subsequent measurements by the same or another trained operator, to assess intra- and interoperator repeatability and reproducibility of the technique. Where feasible, serial measurements were undertaken until the time of extubation in a group of children with prolonged PICU stay (> 5 d).
Measurements And Main Results:
Seventy-three children were enrolled to assess intra- and interoperator ultrasound reliability. Their median (25-75 interquartile range) age and weight were 30 months (4.5-96) and 10 kg (5-23.5). In the intraoperator repeatability study, mean relative difference in quadriceps femoris muscle thickness was 0.36% ± 2.5% (lower and upper limits of agreement: -4.5/+5.2%). In the interoperator reproducibility study, intraclass correlation coefficient was 0.998. In the 17 children monitored over their PICU stay, quadriceps femoris thickness significantly decreased at day 5 by 9.8% (p = 0.006) and by 13.3% (< 0.001) at the last performed measurement.
Conclusions:
Quadriceps femoris thickness decrease, proposed as a surrogate for muscle mass, is an early, frequent, and intense phenomenon in PICU. Quadriceps femoris ultrasonography is a reliable technique to monitor this process and in future could help to guide rehabilitation and nutrition interventions.
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