Wean Earlier and Automatically with New Technology (the WEAN Study) A Multicenter, Pilot Randomized Controlled Trial

Rationale: Automated weaning has not been compared with a paper-based weaning protocol in North America. Objectives: We conducted a pilot randomized trial comparing automated weaning with protocolized weaning in critically ill adults to evaluate clinician compliance and acceptance of the weaning and sedation protocols, recruitment, and impact on outcomes. Methods: From August 2007 to October 2009, we enrolled critically ill adults requiring more than 24 hours of mechanical ventilation and at least partial reversal of the condition precipitating respiratory failure at nine Canadian intensive care units. We randomized patients who tolerated at least 30 minutes of pressure support and either failed or were not yet ready to undergo a spontaneous breathing trial to automated or protocolized weaning. Both groups used pressure support, included spontaneous breathing trials, used a common positive end-expiratory pressure-FIO2 chart, sedation protocol, and criteria for extubation, reintubation, and noninvasive ventilation. Measurements and Main Results: We recruited 92 patients (49 automated, 43 protocolized) over 26 months. Adherence to assigned weaning protocols and extreme sedation scale scores fell within pre-specified thresholds. Combined physician-respiratory therapist and nurse acceptance scores of the study weaning and sedation protocols, respectively, were not significantly different. Automated weaning patients had significantly shorter median times to first successful spontaneous breathing trial (1.0 vs. 4.0 d; P < 0.0001), extubation (3.0 vs. 4.0 d; P = 0.02), and successful extubation (4.0 vs. 5.0 d; P = 0.01), and underwent fewer tracheostomies and episodes of protracted ventilation. Conclusions: Compared with a standardized protocol, automated weaning was associated with promising outcomes that warrant further investigation. Minor protocol modifications may increase compliance, facilitate recruitment, and enhance feasibility.