Critical Illness Neuromyopathy and the Role of Physical Therapy and Rehabilitation in Critically Ill Patients

Neuromuscular complications of critical illness are common, and can be severe and persistent, with substantial impairment in physical function and long-term quality of life. While the etiology of ICU-acquired weakness (ICUAW) is multifactorial, both direct (ie, critical illness neuromyopathy) and indirect (ie, immobility/disuse atrophy) complications of critical illness contribute to it. ICUAW is often difficult to diagnose clinically during the acute phase of critical illness, due to the frequent use of deep sedation, encephalopathy, and delirium, which impair physical examination for patient strength. Despite its limitations, physical examination is the starting point for identification of ICUAW in the cooperative patient. Given the relative cost, invasiveness, and need for expertise, electrophysiological testing and/or muscle biopsy may be reserved for weak patients with slower than expected improvement on serial clinical examination. Currently there are limited interventions to prevent or treat ICUAW, with tight glycemic control having the greatest supporting evidence. There is a paucity of clinical trials evaluating the specific role of early rehabilitation in the chronic critically ill. However, a number of studies support the benefit of intensive rehabilitation in patients receiving chronic mechanical ventilation. Furthermore, emerging data demonstrate the safety, feasibility, and potential benefit of early mobility in critically ill patients, with the need for multicenter randomized trials to evaluate potential short- and long-term benefits of early mobility, including the potential to prevent the need for prolonged mechanical ventilation and/or the development of chronic critical illness, and other novel treatments on patients' muscle strength, physical function, quality of life, and resource utilization. Finally, the barriers, feasibility, and efficacy of early mobility in both medical and other ICUs (eg, surgical, neurological, pediatric), as well as in the chronic critically ill, have not been formally evaluated and require exploration in future clinical trials.