Review of Critical Illness Myopathy and Neuropathy

Abstract

Critical illness myopathy (CIM) and neuropathy are underdiagnosed conditions within the intensive care setting and contribute to prolonged mechanical ventilation and ventilator wean failure and ultimately lead to significant morbidity and mortality. These conditions are often further subdivided into CIM, critical illness polyneuropathy (CIP), or the combination-critical illness polyneuromyopathy (CIPNM). In this review, we discuss the epidemiology and pathophysiology of CIM, CIP, and CIPNM, along with diagnostic considerations such as detailed clinical examination, electrophysiological studies, and histopathological review of muscle biopsy specimens. We also review current available treatments and prognosis. Increased awareness and early recognition of CIM, CIP, and CIPNM in the intensive care unit setting may lead to earlier treatments and rehabilitation, improving patient outcomes.

Neuropathy of Connective Tissue Diseases and Other Systemic Diseases

“…Hypotheses include microcirculatory changes associated with systemic inflammation, increased production of cytokines and reactive oxygen species, and increased permeability of vascular tissue leading to edema in the endoneurial space. 71 Autopsies have revealed chromatolysis of anterior horn cells, loss of dorsal root ganglion cells, and axonal degeneration in peripheral nerves. 72 The diagnosis is generally considered when there is failure of ventilator liberation.…”

“…Muscle biopsy demonstrates features of denervation and reinnervation with small muscle fibers. 71 There is no specific treatment for critical illness polyneuropathy, and care is directed toward preventing the complications of immobility and prolonged mechanical ventilation. A randomized trial showed that early intravenous immunoglobulin was not effective in mitigating neuropathy.…”

Is Nocturnal Extubation After Cardiac Surgery Associated With Worse Outcomes?

“…The increased comorbidity level in patients extubated after 24 hours may make them more prone to worsening decompensation and harder to rescue once decompensation begins. The patients who have been intubated for more than 24 hours may also have critical illness myopathy or neuropathy, which predict failure to wean from the ventilator and may lead to statistically significant morbidity and mortality [30]. This would likely not affect those patients who were extubated in 24 or fewer hours of ICU admission, but it might have a role in the increased mortality of the prolonged intubation group [30].…”

Sepsis-associated encephalopathy

“…They are associated with failure to wean from ventilation, impaired recovery and increased mortality, and usually last longer than sepsis-associated encephalopathy. 3,4…”