Evaluation of muscle loss by ultrasonography in critically ill patients.

Background: Critically ill patients have intense muscle tissue mobilization, and attenuating protein catabolism may contribute to improved outcomes.

Objective: To evaluate short-term muscle loss in critically ill patients.

Methods: In this prospective observational study, we evaluated the thickness of the rectus femoris muscle by ultrasonography in young and older adults of both sexes admitted to a cardiological intensive care unit within 48 h of admission (baseline) and after 7 days.