Increasing compliance with low tidal volume ventilation in the ICU with two nudge-based interventions:Evaluation through intervention time-series analyses

摘要

Objectives: Low tidal volume ventilation improves outcomes for ventilated patients and the majority of clinicians state they implement it. Unfortunately most patients never receive low tidal volumes. “Nudges” influence decision making with subtle cognitive mechanisms and are effective in many contexts. There have been few studies examining their impact on clinical decision-making. We investigated the impact of two interventions designed using principles from behavioural science on the deployment of low tidal volume ventilation in the intensive care unit (ICU).Setting: University Hospitals Bristol, a tertiary, mixed medical and surgical ICU with 20 beds, admitting over1300 patients per year.Participants: Data was collected from 2144 consecutive patients receiving controlled mechanical ventilation for more than 1 hour between October 2010 and September 2014. Patients on controlled mechanical ventilation for more than 20 hours were included in the final analysis.Interventions:1) Default ventilator settings were adjusted to comply with low tidal volume targets from the initiation of ventilation unless actively changed by a clinician.2) A large dashboard was deployed displaying tidal volumes in the format ml/Kg ideal body weight (IBW) with alerts when tidal volumes were excessive.Primary outcome measure: Tidal volume in ml/Kg IBWFindings: Tidal volume was significantly lower in the defaults group. In the dashboard intervention, tidal volume fell more quickly and by a greater amount after a tidal volume of 8ml/Kg IBW was breached when compared with controls. This effect improved in each subsequent year for 3 years. Conclusions: This study has demonstrated that adjustment of default ventilator settings and a dashboard with alerts for excessive tidal volume can significantly influence clinical decision-making. This offers a promising strategy to improve compliance with low tidal volume ventilation and suggests that utilising insights from behavioural science has potential to improve the translation of evidence into practice.