Critical illness myopathy and neuropathy

Area of Science:

• Neurology
• Intensive Care Medicine
• Pathophysiology

Background:

• Muscle wasting and paralysis are frequent complications in Intensive Care Unit (ICU) patients.
• Critical illness polyneuropathy (CIP) and critical illness myopathy (CIM) are the primary causes, often occurring together (CIP/CIM).
• CIP involves sensory-motor polyneuropathy, while CIM is a primary myopathy with varying histological findings.

Purpose of the Study:

• To highlight the diagnostic challenges of CIP and CIM in the ICU.
• To emphasize the importance of differentiating CIP from CIM for prognosis.
• To explore the pathophysiological mechanisms underlying CIP/CIM.

Main Methods:

• Review of diagnostic criteria and neurophysiological methods for CIP/CIM.
• Discussion of clinical manifestations, including ventilator weaning difficulties and limb weakness.
• Consideration of advanced investigations like nerve conduction studies, electromyography, and biopsy.

Main Results:

• CIP/CIM diagnosis is challenging, requiring specialized neurophysiological techniques.
• When diagnosed, CIM is as frequent as or more frequent than CIP.
• CIM appears to have a better prognosis than CIP, making differential diagnosis critical.

Conclusions:

• Accurate diagnosis and differentiation of CIP and CIM are essential for predicting long-term outcomes in ICU survivors.
• Bioenergetic failure is a proposed unifying pathophysiological mechanism for CIP/CIM and multi-organ failure.
• CIP/CIM represents a failure of the peripheral nervous-muscular system, impacting patient recovery.