Myopathies in Neurocritical Care

Myopathy in critical care complicates the course of the primary critical illness by significantly potentiating patient morbidity in intensive care units (ICU). The development of this rare but serious complication poses a potential threat of progression to respiratory paralysis if not promptly diagnosed and optimally managed. This disorder has been reported to affect as many as 43% of critically debilitated patients in the intensive care unit. Patient’s age, body mass index, comorbid illnesses, the severity of the primary disease, multisystemic organ dysfunction, exposure to neurotoxic and myotoxic drugs, and prolonged immobility are among the significant risk factors for this condition. The pathophysiological process that underlies this spectrum of secondary muscular paralysis is multifactorial and complex to comprehend. This is subdivided into critical illness polyneuropathy (CIP), critical illness myopathy (CIM), and critical illness neuromyopathy (CINM), depending on the various structural and functional alterations of myofibers and neurons that underlie these disorders. Fortunately, this functionally crippling clinical condition is amenable to a few feasible preventive medical practices and is under continuous scrutiny in current neurocritical care research. This chapter presents a comprehensive discussion of the recent insights into the different constituents of ICU-acquired weakness, their varied clinical presentations, detailed panel for their diagnostic workup, differential diagnosis of other clinical mimics, prognostication, short- and long-term repercussions, and the key preventive and management strategies.