Critical Illness Polyneuropathy

Overview


Plain-Language Overview

Critical Illness Polyneuropathy (CIP) is a condition that affects the nerves in people who are very sick and often in the intensive care unit. It mainly involves the peripheral nerves, which are responsible for moving muscles and sensing touch, pain, and temperature. This condition causes muscle weakness and difficulty moving, which can make it hard to breathe or get out of bed. CIP usually develops after a serious illness or injury that causes widespread inflammation in the body. The nerve damage slows down communication between the brain and muscles, leading to problems with strength and sensation. It can delay recovery and increase the time a person needs to stay in the hospital. Overall, CIP impacts the nervous system and the ability to perform everyday movements.

Clinical Definition

Critical Illness Polyneuropathy (CIP) is an acute, diffuse, symmetric axonopathy of the peripheral nerves occurring in critically ill patients, especially those with sepsis, multi-organ failure, or prolonged mechanical ventilation. The core pathology involves axon degeneration of motor and sensory fibers, leading to muscle weakness, decreased or absent reflexes, and sensory deficits. CIP is thought to result from systemic inflammatory responses causing microvascular and metabolic disturbances in peripheral nerves. It is a major cause of neuromuscular weakness in the intensive care setting and contributes to difficulty weaning from mechanical ventilation. Electrophysiological studies typically show reduced compound muscle action potentials and sensory nerve action potentials. CIP often coexists with critical illness myopathy, complicating clinical assessment. Early recognition is important due to its impact on morbidity and prolonged rehabilitation.

Clinical Presentation


Diagnostic Workup


Pathophysiology


Treatments


Prevention


Outcome & Complications


Differential Diagnoses


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