Preventing Respiratory Failure After Cardiac Surgery Using Post-extubation Bilevel Positive Airway Pressure Therapy

Abstract

Objective: Our study aimed to evaluate if an extubation protocol for all post-operative cardiac patients in the cardiothoracic intensive care unit using intermittent bilevel positive airway pressure (BiPAP) could reduce the rate of re-intubation. Methods: A total of 1,718 patients undergoing cardiac surgery from May 2012 to April 2016 were analyzed. Patients from May 2014 to April 2016 were included in a post-extubation BiPAP therapy protocol that included one hour of BiPAP followed by three hours of a nasal cannula for 24 hours after extubation in the cardiothoracic intensive care unit. The protocol cohort was retrospectively compared to a control group (nasal cannula only) from May 2012 to April 2014. All demographic and outcome data were analyzed from our institution’s Society of Thoracic Surgeons (STS) Cardiac Database. Results: There was no statistical difference in the rate of re-intubation between the BiPAP group (n = 35; 4.07%) and the control group (n = 34; 3.96%; p = 0.9022). Sub-group analysis of the 69 re-intubated patients identified several significant risk factors: prior valve surgery (p = 0.028), chronic lung disease (p = 0.0343), emergent operation (p = 0.0016), longer operating room time (p = 0.0109), cardiopulmonary bypass time (p = 0.0086), higher STS predicted risk of mortality score (p = 0.0015). Re-intubation was associated with higher 30-day mortality rates (p = 0.0026), prolonged cardiothoracic intensive care unit length of stay (p < 0.0001), and hospital length of stay (p < 0.0001). Conclusion: While a BiPAP protocol did not show a significant difference in re-intubation rates after cardiac surgery, the subgroup analysis of re-intubated patients showed several significant risk factors for re-intubation. Early identification of these risk factors when considering extubation may help teams avoid associated morbidity and mortality outcomes.