Impact of Vasoactive Medications on ICU-Acquired Weakness in Mechanically Ventilated Patients

Background: Vasoactive medications are commonly used in the treatment of critically ill patients, but their impact on the development of ICU-acquired weakness is not well described. The objective of this study is to evaluate the relationship between vasoactive medication use and the outcome of ICU-acquired weakness. Methods: This is a secondary analysis of mechanically ventilated patients (N = 172) enrolled in a randomized clinical trial of early occupational and physical therapy vs conventional therapy, which evaluated the end point of ICU-acquired weakness on hospital discharge. Patients underwent bedside muscle strength testing by a therapist blinded to study allocation to evaluate for ICU-acquired weakness. The effects of vasoactive medication use on the incidence of ICU-acquired weakness in this population were assessed. Results: On logistic regression analysis, the use of vasoactive medications increased the odds of developing ICU-acquired weakness (odds ratio [OR], 3.2; P =.01) independent of all other established risk factors for weakness. Duration of vasoactive medication use (in days) (OR, 1.35; P =.004) and cumulative norepinephrine dose (μg/kg/d) (OR, 1.01; P =.02) (but not vasopressin or phenylephrine) were also independently associated with the outcome of ICU-acquired weakness. Conclusions: In mechanically ventilated patients enrolled in a randomized clinical trial of early mobilization, the use of vasoactive medications was independently associated with the development of ICU-acquired weakness. Prospective trials to further evaluate this relationship are merited. Trial Registry: ClinicalTrials.gov; No.: NCT01777035; URL: www.clinicaltrials.gov