What is critical illness myopathy (CIM)/polyneuropathy (CIP)?

From the Guidelines

Critical illness myopathy (CIM)/polyneuropathy (CIP) is a neuromuscular disorder that develops in critically ill patients, typically those in intensive care units, involving muscle weakness and nerve dysfunction as a complication of severe illness, sepsis, multi-organ failure, or prolonged mechanical ventilation, as stated in the 2023 guideline on multimodal rehabilitation for patients with post-intensive care syndrome 1.

Definition and Presentation

CIM/CIP presents as generalized weakness, particularly affecting the limbs and respiratory muscles, which can delay recovery and weaning from ventilator support. It typically develops within days to weeks of critical illness and can significantly extend hospital stays.

Risk Factors

Risk factors for CIM/CIP include sepsis, systemic inflammatory response syndrome, multiple organ failure, hyperglycemia, and prolonged use of neuromuscular blocking agents or corticosteroids, as highlighted in the 2021 espen guideline on clinical nutrition in hospitalized patients with acute or chronic kidney disease 1.

Diagnosis and Treatment

Diagnosis involves clinical examination, electromyography, nerve conduction studies, and sometimes muscle biopsy. Treatment is primarily supportive, focusing on treating the underlying critical illness, maintaining proper nutrition, controlling blood glucose levels, minimizing sedation, and implementing early physical therapy and rehabilitation.

Prevention Strategies

Prevention strategies include tight glycemic control, minimizing use of steroids and neuromuscular blockers when possible, and early mobilization of patients, as recommended in the 2023 guideline on multimodal rehabilitation for patients with post-intensive care syndrome 1.

Recovery and Outcomes

Recovery can take weeks to months, with some patients experiencing long-term weakness, though many eventually regain significant function through rehabilitation. The 2023 guideline on multimodal rehabilitation for patients with post-intensive care syndrome emphasizes the importance of screening critically ill patients for risk factors to develop post-intensive care syndrome (PICS) and symptoms of PICS during the stay in intensive care, after discharge, during and at the end of rehabilitation, as well as in out-patient care 1. Some key points to consider in the management of CIM/CIP include:

• Early identification and management of risk factors
• Implementation of supportive treatment, including proper nutrition and physical therapy
• Minimizing the use of neuromuscular blocking agents and corticosteroids
• Early mobilization of patients
• Screening for PICS and symptoms of PICS during and after intensive care.

From the Research

Definition and Overview

• Critical illness myopathy (CIM) and polyneuropathy (CIP) are underdiagnosed conditions in the intensive care setting, contributing to prolonged mechanical ventilation and significant morbidity and mortality 2.
• These conditions can be further subdivided into CIM, CIP, or a combination of both, known as critical illness polyneuromyopathy (CIPNM) 2.
• CIP and CIM are major complications of severe critical illness and its management, prolonging weaning from mechanical ventilation and physical rehabilitation 3.

Epidemiology and Risk Factors

• CIP and CIM are associated with increased hospital and intensive care unit (ICU) stays and increased mortality rates 3.
• Sepsis, systemic inflammatory response syndrome, and multiple organ failure appear to play a crucial role in the development of CIP and CIM 3.
• The use of corticosteroids and nondepolarizing neuromuscular-blocking agents can also contribute to the development of CIM 4.

Clinical Features and Diagnosis

• CIP and CIM present as limb weakness and difficulty in weaning from the ventilator 5.
• Diagnosis depends on neurological examination, electrophysiological studies, measurement of serum creatine kinase, and muscle biopsy (if features suggest a myopathy) 5.
• Early recognition and diagnosis of CIP and CIM are crucial for improving patient outcomes 2.

Treatment and Management

• There are no specific pharmacologic treatments for CIP or CIM, but recognizing the presence of one of these disorders can improve management 4.
• Intensive insulin therapy in ICU patients appears to reduce the likelihood of developing CIP and/or CIM 3, 4.
• Early mobilization, kinesiotherapy, and exercises have shown to improve muscle strength and reduce weaning time and length of hospitalization 6.