Intensive care unit-acquired weakness and mechanical ventilation: A reciprocal relationship.

Intensive care unit-acquired weakness (ICU-AW; ICD-10 Code: G72.81) is a syndrome of generalized weakness described as clinically detectable weakness in critically ill patients with no other credible cause. The risk factors for ICU-AW include hyperglycemia, parenteral nutrition, vasoactive drugs, neuromuscular blocking agents, corticosteroids, sedatives, some antibiotics, immobilization, the disease severity, septicemia and systemic inflammatory response syndrome, multiorgan failure, prolonged mechanical ventilation (MV), high lactate levels, older age, female sex, and pre-existing systemic morbidities. There is a definite association between the duration of ICU stay and MV with ICU-AW. However, the interpretation that these are modifiable risk factors influencing ICU-AW, appears to be flawed, because the relationship between longer ICU stays and MV with ICU-AW is reciprocal and cannot yield clinically meaningful strategies for the prevention of ICU-AW. Prevention strategies must be based on other risk factors. Large multicentric randomized controlled trials as well as meta-analysis of such studies can be a more useful approach towards determining the influence of these risk factors on the occurrence of ICU-AW in different populations.