From the Guidelines
ICU-acquired weakness (ICUAW) is a condition characterized by muscle weakness that develops during a critical illness in patients admitted to the intensive care unit, affecting both the limbs and respiratory muscles, and is associated with worsened outcomes, including prolonged mechanical ventilation, delayed recovery, and decreased quality of life. This condition typically occurs in patients who have been critically ill for more than 1-2 weeks, particularly those with sepsis, multi-organ failure, or those requiring prolonged mechanical ventilation 1. The pathophysiology of ICUAW involves a combination of factors, including systemic inflammation, immobility, certain medications (such as corticosteroids and neuromuscular blocking agents), hyperglycemia, and nutritional deficiencies, leading to muscle atrophy and dysfunction of the peripheral nerves 1.
Diagnosis and Management
Diagnosis of ICUAW is typically made through clinical examination, showing symmetrical weakness and reduced deep tendon reflexes, and may also involve electrophysiological testing, such as electromyography (EMG) and nerve conduction studies (NCS) 1. Management of ICUAW focuses on prevention through early mobilization, minimizing sedation, glycemic control, and proper nutrition, as well as physical therapy and rehabilitation, beginning as early as possible during the ICU stay and continuing after discharge 1.
Recent Guidelines
Recent guidelines emphasize the importance of early mobilization and rehabilitation in preventing and managing ICUAW, as well as the need for a multidisciplinary approach to address the physical, cognitive, and psychological impairments associated with post-intensive care syndrome (PICS) 1. Early recognition and intervention are critical in improving outcomes and reducing the risk of long-term or permanent weakness, and healthcare providers should prioritize prevention and management strategies to minimize the impact of ICUAW on patients' quality of life and functional independence.
From the Research
Definition and Characteristics of ICU Acquired Weakness
- ICU acquired weakness is a condition that occurs in critically ill patients, resulting in sustained disability long after the ICU stay 2.
- It is characterized by profound weakness, muscle wasting, impaired contractility, neuropathy, and major pathways associated with muscle protein degradation 2, 3.
- The condition is often accompanied by dysfunction of multiple organ systems and can result in significant activity limitations, requiring physical assistance for basic activities 4.
Risk Factors and Diagnosis
- Risk factors for ICU acquired weakness include illness severity and organ failure, age, hyperglycemia, parenteral nutrition, drugs, and immobility 3.
- Diagnosis can be made using electrophysiological methods, and patients can be classified into three subcategories: critical illness polyneuropathy, critical illness myopathy, and critical illness neuromyopathy 3.
- The Medical Research Council (MRC) scale can be used to assess ICU acquired weakness in patients 5.
Management and Prevention
- Management of ICU acquired weakness is essentially preventive, avoiding modifiable risk factors such as duration of sedation and immobilization 3.
- Early mobilization, range of motion exercises, and neuromuscular electrical stimulation (NMES) can help prevent ICU acquired weakness by maintaining muscle mass 6, 5.
- Combining NMES with early physical activity has been shown to be effective in preventing ICU acquired weakness and reducing the duration of mechanical ventilation and ICU stay 5.
Prognosis and Recovery
- ICU acquired weakness can result in longer hospital stay and increased mortality 3.
- Recovery from ICU acquired weakness can be improved with early physical activity and NMES, and daily sessions of these interventions have been shown to be well tolerated and effective in preserving muscle strength 5.
- Patients with ICU acquired weakness often have significant activity limitations months to years after hospitalization, highlighting the need for long-term rehabilitation and management 4.