Outcomes and Risk Factors Associated with Prolonged Intubation after EVAR

Background: Time to discharge has decreased for aortic surgery since the advent of endovascular aortic aneurysm repair (EVAR), partially due to improved perioperative management. We aimed to investigate outcomes and risk factors associated with prolonged intubation following EVAR. Methods: The Vascular Study Group of New England (VSGNE) database was queried to select all patients who underwent elective EVAR between January 2003 and December 2014. Patients who were not extubated in the operating room were classified as having prolonged intubation. Patients requiring prolonged intubation were compared with those extubated in the operating room using t-test and chi-square statistics. Kaplan-Meier survival analyses estimated all-cause mortality. Independent predictors associated with prolonged intubation, including postoperative pneumonia or respiratory failure, were examined using multivariable logistic regression. Results: A total of 3,979 patients were identified within the elective EVAR VSGNE data set, among whom 5.2% required prolonged intubation. Patients with prolonged intubation were older, more frequently female, non-Hispanic, had larger aneurysms, and had a more frequent diagnoses of diabetes, congestive heart failure, coronary artery disease, ejection fraction <50%, and chronic obstructive pulmonary disease (all P < 0.05). Respiratory complications occurred in 25.5% of patients with prolonged intubation vs. 1.8% of patients who were extubated in the operating room (P < 0.001). Kaplan-Meier survival estimates suggested patients requiring prolonged intubation after EVAR had significantly lower survivals than those who extubated in the operating room (P < 0.05). On multivariable analysis, independent risk factors associated with prolonged intubation included subjective lack of fitness for open procedure (OR: 4.8, 95% confidence interval [CI]: 3.5-8.7), ejection fraction < 50% (1.8, 1.3-2.8), and ASA class >3 (1.5, 1.1-1.7). Conclusions: Prolonged intubation following EVAR is associated with increased risk of postoperative respiratory complications, as well as decreased long-term survival. High-risk patients for prolonged intubation, including those deemed subjectively unfit for an open procedure, ejection fraction <50% and ASA class >3, may not benefit from an elective EVAR.