Neuromuscular dysfunction acquired during critical illness: a systematic review
© BioMed Central Ltd. 2007
Published: 22 March 2007
Patients with critical illness can acquire a syndrome of weakness and dependence on mechanical ventilation that has been linked to peripheral nerve and muscle injury. Our aim was to systematically review published data on the diagnosis, risk factors and outcomes of patients with critical illness neuromuscular abnormalities (CINMA).
MEDLINE, EMBASE, CINAHL, and the Cochrane Library were searched, and studies were included if they reported on ICU patients > 16 years old who were evaluated for CINMA clinically and electrophysiologically, and they contained sufficient data to quantitatively measure the association between CINMA and clinically relevant exposures and/or outcomes. Two reviewers independently extracted data on study methodology and quality, methods for diagnosing CINMA, and CINMA prevalence, risk factors, and outcomes.
In 1,421 ICU patients who were evaluated in 24 studies, 655 (46%) were diagnosed with CINMA. All enrolled patients were receiving protracted mechanical ventilation, had sepsis, or had multiple organ failure. Diagnostic criteria for CINMA were heterogeneous and few reports explicitly differentiated between the polyneuropathic, myopathic and mixed types of CINMA. CINMA was linked in several studies to hyperglycemia, the systemic inflammatory response syndrome, sepsis, renal replacement therapy, and catecholamine administration. In contrast, across studies there was no consistent relationship between CINMA and patient age, gender, severity of illness, multiple organ failure, and use of glucocorticoids, neuromuscular blockers, aminoglycosides, or midazolam. Mortality was not increased in patients with CINMA, but mechanical ventilation and ICU and hospital stays were prolonged.
The risk of CINMA is nearly 50% in a subset of ICU patients with sepsis, multiorgan failure, or protracted mechanical ventilation, but there were no data to support CINMA as an independent predictor of death. The impact of frequently cited risk factors is uncertain, but emerging data indicate glycemic control decreases CINMA risk in vulnerable patients.