Neuromuscular Ultrasound in Intensive Care Unit-Acquired Weakness: Current State and Future Directions

Intensive care unit-acquired weakness (ICUAW) is one of the most common causes of muscle atrophy and functional disability in critically ill intensive care patients. Clinical examination, manual muscle strength testing and monitoring are frequently hampered by sedation, delirium and cognitive impairment. Many different attempts have been made to evaluate alternative compliance-independent methods, such as muscle biopsies, nerve conduction studies, electromyography and serum biomarkers. However, they are invasive, time-consuming and often require special expertise to perform, making them vastly impractical for daily intensive care medicine. Ultrasound is a broadly accepted, non-invasive, bedside-accessible diagnostic tool and well established in various clinical applications. Hereby, neuromuscular ultrasound (NMUS), in particular, has been proven to be of significant diagnostic value in many different neuromuscular diseases. In ICUAW, NMUS has been shown to detect and monitor alterations of muscles and nerves, and might help to predict patient outcome. This narrative review is focused on the recent scientific literature investigating NMUS in ICUAW and highlights the current state and future opportunities of this promising diagnostic tool.

Automated summary

Intensive care unit-acquired weakness (ICUAW) is a common cause of muscle atrophy and functional disability in critically ill patients. Evaluating ICUAW is challenging due to sedation, delirium, and cognitive impairment. While invasive methods like muscle biopsies and nerve conduction studies have been attempted, they are impractical for daily use in intensive care medicine. Non-invasive neuromuscular ultrasound (NMUS) shows promise in detecting and monitoring muscle and nerve alterations in ICUAW, with potential for predicting patient outcome. This review highlights the current state and future opportunities of NMUS in ICUAW.