Purpose of review: To investigate the impact of critical illness polyneuropathy and critical illness myopathy on short-term and long-term patient outcome.
Recent findings: In the acute-care setting, critical illness polyneuropathy and critical illness myopathy are important causes of acute paralysis in critically ill comatose patients, and may cause inappropriately pessimistic prognoses. Duration of weaning from artificial ventilation is 2 to 7 times greater in patients with critical illness polyneuropathy than in patients without critical illness polyneuropathy. After intensive care unit and hospital discharge, many patients diagnosed with critical illness polyneuropathy or critical illness myopathy are reported to complain of profound muscle weakness. Chronic disability was a common finding among them. Complete functional recovery with patients regaining the ability to breathe spontaneously and to walk independently was reported in 180 of 263 patients (68.4%); severe disability with tetraparesis, tetraplegia, or paraplegia was reported in 74 patients (28.1%). Persisting milder disabilities were common even in patients with complete functional recovery, and included reduced or absent deep tendon reflexes, stocking and glove sensory loss, muscle atrophy, painful hyperesthesia, and foot drop. An association of critical illness polyneuropathy and critical illness myopathy with increased intensive care unit and hospital mortality has been demonstrated only in selected intensive care unit populations; data are insufficient to demonstrate any association with long-term mortality.
Summary: Intensive care unit-acquired critical illness polyneuropathy and critical illness myopathy influence the evaluation of acutely ill comatose patients and may instigate unreasonably pessimistic prognosis. Critical illness polyneuropathy and critical illness myopathy are an important cause of difficult weaning of patients from the ventilator and of persisting muscle weakness and disability after intensive care unit discharge.