Ultrasound to Evaluate the Quadriceps Muscle Wasting

Intensive care unit acquired muscle weakness (ICUAW) is a common disease. After 7 days of mechanical ventilation, a quarter of patients develop an ICUAW responsible of a 15-20% of muscle loss. This is a serious pathology associated with high morbidity and mortality. Clinical diagnosis of ICUAW is difficult and need a patient awoken. CT scan and Magnetic Resonance Imaging (MRI) are considered as "gold standards" to quantify and monitor changes in muscle mass. But these tools are not adapted to ICU patients. Ultrasound (US) is an easy access tool at the bedside to assess muscle mass and does not expose the patient to additional radiation. The objective of this study is to evaluate the correlation between US and CT scan to measure quadriceps muscle thickness of ICU patients.