From the Guidelines
ICU-acquired weakness (ICUAW) is defined as a condition characterized by new or increased impairments of physical functions, including neuromuscular functions of swallowing, breathing, mobility, and personal autonomy, that develop during a critical illness in patients admitted to the intensive care unit. This condition is a part of the post-intensive care syndrome (PICS), which consists of a neurologically heterogeneous complex of impairments that can be observed in critically ill patients after treatment in an ICU 1. The symptoms of ICUAW can include difficulty in movement, prolonged mechanical ventilation, and delayed recovery, and can be diagnosed through clinical examination, electrophysiological studies, and sometimes muscle biopsy.
The development of ICUAW is associated with multiple factors, including systemic inflammation, medications (particularly corticosteroids and neuromuscular blocking agents), prolonged immobility, and metabolic derangements that occur during critical illness 2, 3, 4. Prevention strategies for ICUAW include early mobilization, minimizing sedation, careful glycemic control, and judicious use of corticosteroids and neuromuscular blockers.
Treatment for ICUAW primarily involves physical rehabilitation starting as early as possible during the ICU stay and continuing after discharge, with a multidisciplinary approach including physical therapists, occupational therapists, and rehabilitation specialists to help patients regain strength and function 1. The goal of treatment is to improve the patient's physical, cognitive, and psychological health, and to promote clinical decisions and standards of care that improve the outcomes of adult patients at risk for developing or affected by symptoms of PICS.
Some key points to consider when managing ICUAW include:
- Early identification and diagnosis of ICUAW to initiate prompt treatment
- Multidisciplinary approach to treatment, including physical therapists, occupational therapists, and rehabilitation specialists
- Focus on improving physical function, mobility, and personal autonomy
- Consideration of the patient's overall health status, including cognitive and psychological function, when developing a treatment plan
- Need for ongoing rehabilitation and support after discharge from the ICU to promote long-term recovery and improvement in quality of life.
From the Research
Definition of ICU Acquired Weakness
ICU acquired weakness (ICUAW) is defined as a de novo form of muscle weakness that develops in patients during their stay in the intensive care unit (ICU) due to critical illness, complicated surgery, severe trauma, or burn injury 5, 6. It is a broad term that includes several specific neuromuscular problems, such as critical illness polyneuropathy (CIP), critical illness myopathy (CIM), and disorders of neuromuscular junction transmission 7.
Characteristics of ICU Acquired Weakness
ICUAW is typically symmetrical and affects predominantly proximal limb muscles and respiratory muscles, whereas facial and ocular muscles are often spared 5. The main risk factors for ICUAW include:
- High severity of illness upon admission
- Sepsis
- Multiple organ failure
- Prolonged immobilization
- Hyperglycemia
- Older age 5, 6, 8
Diagnosis and Prognosis
ICUAW is diagnosed in awake and cooperative patients by bedside manual testing of muscle strength, and the severity is scored by the Medical Research Council sum score 5. The prognosis appears compromised when the cause of ICUAW involves critical illness polyneuropathy, whereas isolated critical illness myopathy may have a better prognosis 5. Recovery usually occurs within weeks or months, although it may be incomplete with weakness persisting up to 2 years after ICU discharge 5.