What is the treatment for muscle weakness in Intensive Care Unit (ICU) patients?

Treatment for Muscle Weakness in ICU Patients

Early physical rehabilitation with systematically augmented levels of mobilization is the most effective treatment for ICU-acquired weakness (ICUAW) and should be initiated as soon as the patient is hemodynamically stable. 1

Assessment of ICU-Acquired Weakness

• The six-point Medical Research Council (MRC) score is the recommended tool to assess muscle strength in ICU patients, with an MRC sum score less than 48 (or mean MRC less than 4 per muscle group) defining ICU-acquired weakness 1, 2
• Handgrip strength dynamometry provides a simple diagnostic method for early detection of ICUAW before changes in body composition parameters are identified 1, 2
• In communicative patients, the 0-10 Numeric Rating Scale (NRS) can be used for self-reporting weakness symptoms 2
• ICUAW typically presents with symmetric weakness affecting multiple muscle groups, including respiratory muscles 2

Treatment Approach

Early Mobilization and Physical Therapy

• Early mobilization should be initiated after initial cardiorespiratory and neurological stabilization 1
• Physical therapy should include:
  • Positioning changes to increase gravitational stress and associated fluid shifts 1
  • Progressive mobilization starting with passive range of motion and advancing to active exercises 1
  • Standing and walking with appropriate aids (modified walking frames, tilt tables) 1
  • Aerobic training and muscle strengthening exercises 1

Specific Physical Rehabilitation Protocol

• Provide additional physiotherapy with systematically augmented levels of mobilization (5 times per week, 20 minutes per session) 3
• Include sitting balance exercises, stretching, positioning, sit-to-stand training, transfer training, strengthening exercises, and stepping/standing exercises 3
• For patients unable to actively participate, consider in-bed cycling as an alternative intervention 3

Nutritional Support

• Monitor and address micronutrient deficiencies, particularly in patients on continuous renal replacement therapy (CRRT) 1
• Test for micronutrient status after 6-7 days in ICU, with particular attention to copper, selenium, zinc, and iron levels 1
• Consider values 20% below laboratory reference as concerning and initiate repletion 1
• Monitor muscle mass using ultrasound or CT scan (if already being performed for other clinical reasons) 1

Prevention Strategies

• Aggressive treatment of sepsis, which is a major risk factor for ICUAW 4, 5
• Prevent hyperglycemia with insulin therapy 6, 4
• Avoid prolonged immobilization 1, 4
• Restrictive use of immobilizing medications, particularly neuromuscular blocking agents 7, 4
• Optimize nutrition while avoiding overfeeding 1, 7
• Consider activating ventilatory modes to maintain respiratory muscle activity 7

Monitoring Progress

• Reassess muscle strength regularly using the MRC score 1, 2
• Monitor functional improvement using the Functional Status Score for the Intensive Care Unit (FSS-ICU) 3
• Track walking ability using the Functional Ambulation Category (FAC) 3
• Assess sit-to-stand recovery, overall limb strength, and grip strength 3

Important Considerations and Pitfalls

• The risk of mobilizing critically ill patients should be weighed against the risks of immobility and recumbency 1
• Patients with hemodynamic instability, high FiO2, and high levels of ventilatory support are not candidates for aggressive mobilization 1
• Assessment tools requiring patient cooperation (like handgrip strength) have limitations in uncooperative or sedated patients 2
• Recovery from ICUAW usually occurs within weeks or months but may be incomplete with weakness persisting up to 2 years after ICU discharge 4
• ICUAW contributes to the risk of 1-year mortality, highlighting the importance of effective treatment 4