Association of Overnight Extubation With Outcomes After Cardiac Surgery in the Intensive Care Unit

Background: The frequency and safety of overnight extubation (OE) after cardiac surgery across intensive care units (ICUs) is unknown.

Methods: We performed a retrospective study of adults (≥ 18 years) in US ICUs after coronary artery bypass grafting (CABG) or aortic valve replacement (AVR) or both, using The Society of Thoracic Surgery Adult Cardiac Surgery Database (July 2014 to June 2017); our primary cohort was elective CABGs. We assessed OE (7:00 pm to 6:59 am) frequency and used multilevel regression modelling to identify factors associated with OE. Within mechanical ventilation (MV) duration strata, we used propensity score matching to evaluate associations of OE with reintubations (primary outcome), mortality, and complications.

Results: Among 142,225 patients with elective CABG, 42.2% had OEs. MV duration, cardiopulmonary bypass time, distal anastomosis number, and hospital of admission (median odds ratio [OR] 1.82, 95% confidence interval [CI]: 1.76 to 1.89) were independently associated with OE. After propensity matching, OE was associated with increased reintubation for patients with MV duration of 6 to 8 hours (2.2% vs 1.7%, OR 1.27, 95% CI: 1.04 to 1.56) and decreased reintubation for patients with MV duration of 15 to 17 hours (3.0% vs 4.2%, OR 0.70, 95% CI: 0.50 to 0.97) and 18 to 20 hours (2.3% vs 5.7%, OR 0.39, 95% CI: 0.21 to 0.72); OE was associated with increased ICU length of stay for patients with MV duration of 6 to 8 hours, but reduced length of stay for patients with MV duration of 9 to 20 hours. OE was not associated with increased mortality (hospital, 30-day). Other groups had similar OE rates (nonelective CABGs, 47.6%; elective AVR, 36.0%; elective CABG + AVRs, 51.0%) and outcomes.

Conclusions: OE is prevalent after cardiac surgery. OE is associated with little risk and reduces ICU length of stay for patients who require MV for more than 8 hours.