Liberation from Invasive Mechanical Ventilation with Continued Receipt of Vasopressor Infusions

Rationale: Weaning protocols for discontinuation of invasive mechanical ventilation often mandate resolution of shock. Whether extubation while receiving vasopressors is associated with harm is uncertain. Objectives: To examine whether extubation while still receiving vasopressors is associated with worse outcomes. Methods: We performed a retrospective cohort study of adults in Calgary ICUs who received vasopressors with invasive mechanical ventilation and an extubation attempt. The primary exposure was continued vasopressor use at extubation. The primary outcome was reintubation within 96 hours. Secondary outcomes included in-hospital mortality and ICU/hospital length of stay (LOS). We assessed associations of vasopressor use at extubation with outcomes using multivariable competing-risk (reintubation/LOS) and Cox proportional-hazards (mortality) models. Measurements and Main Results: Of 6,140 patients who received invasive mechanical ventilation while on vasopressors, 721 (11.7%) were extubated while receiving vasopressors, and 5,419 (88.3%) after discontinuation. Extubation on vasopressors was not, in aggregate, significantly associated with an increased hazard of reintubation (subhazard ratio [SHR], 1.81 [95% confidence interval, 0.91-3.61]; P = 0.09). Both mortality (hazard ratio, 1.22 [1.02-1.47]; P = 0.03) and time to hospital discharge (SHR for remaining hospitalized, 0.78 [0.68-0.91]; P < 0.01) were increased. Extubation on high-dose vasopressors (>0.1 μg/kg/min) was associated with a greater hazard of reintubation (SHR, 2.25 [1.01-4.98]; P = 0.046) compared with extubation after vasopressor discontinuation. Meanwhile, extubation on low-dose vasopressors (⩽0.1 μg/kg/min) was associated with a lower mortality (hazard ratio, 0.69 [0.51-0.91]; P = 0.01) and a shorter ICU LOS (SHR, 1.34 [1.09-1.65]; P = 0.01), but no difference in reintubation or hospital LOS as compared with those weaned off vasopressors. Conclusions: Extubation while receiving high-dose but not low-dose vasopressors was associated with an increased risk of reintubation.