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143: EARLY BETA-BLOCKER REINITIATION AFTER VASOPRESSOR EXPOSURE AND RATE OF AF AFTER NONCARDIAC SURGERY

Learning Objectives: Post-operative atrial fibrillation (POAF) after non-cardiac surgery impacts 3-15% of patients, and correlates with an increased hospital stay and mortality. Current literature shows an increased incidence of POAF if beta-blockade is restarted after post-operative day one. Little is known about the appropriate timing of beta-blocker (BB) reinitiation in critically ill patients requiring vasoactive therapies peri-operatively. Methods: A retrospective cohort analysis was performed of 8201 adult surgical patients undergoing non-cardiac surgery from 2005-2015 who were chronically on BB pre-operatively and required continuous infusion vasopressor therapy (CIVT) in the peri-operative period. Patients were excluded if they underwent cardiac surgery within 30 days, had a post-operative stay less than 72 hours, were age > 75 years, or had an AICD. Time to BB was calculated from the first documented CIVT free period to first BB administered. Patients were divided into early restart (within 24 hours of CIVT cessation) and late restart groups. The primary outcome measured was incidence of POAF. A propensity score was developed for early BB and used for multivariable logistic regression adjustment. Results: A total of 220 patients (2.7%) required post-operative CIVT; with 73 in the early group and 117 in the late group. Baseline comorbid conditions were no different. However, intraoperative vasopressor exposure (adjusted OR = 11.4) and use of phenylephrine impacted likelihood of early beta blockade (adjusted OR = 1.8). Ten patients developed POAF: 3 (3.6%) in the early BB reinitiation group, & 7 (5.1%) in the late group (p = 0.746). After propensity score adjustment, early BB resumption was not associated with POAF. Post-operative and hospital stay were shorter in the early BB reinitiation group (p < 0.005). Conclusions: In a small subset of patients requiring post-operative CIVT, early BB reinitiation did not protect against POAF. These patients may have been preemptively identified as high risk and exposed to less beta-adrenergic vasopressors peri-operatively. A small event rate significantly limited the study.