From the Guidelines
ICU-acquired weakness (ICUAW) primarily consists of three main types: critical illness polyneuropathy (CIP), critical illness myopathy (CIM), and critical illness neuromyopathy (CINM). These conditions typically develop in critically ill patients due to multiple factors including systemic inflammation, medication effects (particularly corticosteroids and neuromuscular blocking agents), immobility, hyperglycemia, and multi-organ failure 1.
Types of ICU-AW
- Critical illness polyneuropathy (CIP) affects peripheral nerves, causing sensory and motor deficits with preserved facial muscle function.
- Critical illness myopathy (CIM) involves direct muscle damage with normal sensory function but reduced muscle strength and atrophy.
- Critical illness neuromyopathy (CINM) is a combination of both conditions, presenting with features of both nerve and muscle involvement. Diagnosis involves clinical examination, electrophysiological studies, and sometimes muscle biopsy 2.
Prevention and Management
Prevention strategies include minimizing sedation, early mobilization, glycemic control, and judicious use of corticosteroids and neuromuscular blockers 1. Recovery can take weeks to months, with some patients experiencing long-term disability, making early recognition and preventive measures crucial in ICU management. According to the most recent guideline on multimodal rehabilitation for patients with post-intensive care syndrome, early recognition and prevention of ICUAW are essential to improve patient outcomes 1.
From the Research
Types of ICU Acquired Weakness
- Critical illness polyneuropathy (CIP) 3, 4, 5, 6
- Critical illness myopathy (CIM) 3, 4, 5, 6
- Critical illness neuromyopathy (CIPNM) 3, 4, 6
Characteristics of Each Type
- Critical illness polyneuropathy: involves sensorimotor axons, manifests as limb and respiratory muscle weakness 5, 6
- Critical illness myopathy: involves skeletal muscles, manifests as limb and respiratory muscle weakness 5
- Critical illness neuromyopathy: an overlap syndrome, involves both peripheral nerves and skeletal muscle 3, 4, 6
Diagnosis and Differentiation
- Clinical and electrophysiological tools are used for diagnosis, each with advantages and limitations 3, 7
- Nerve conduction studies and needle electromyography can be used to diagnose CIP and differentiate it from CIM and other conditions 6
- Sensory nerve conduction studies can be used to differentiate CIP from CIM 6