Examining safety of cardiac surgery in patients with preoperative cardiac arrest

Background Although postoperative cardiac arrest is a well-studied complication of cardiac surgery, few guidelines exist regarding timing of surgery in preoperative cardiac arrest (pCA). We examined the association between delayed timing of operation and postoperative outcomes following cardiac surgery in a large cohort of pCA.Methods Adults with a diagnosis of pCA undergoing a cardiac operation were identified in the 2016-2020 National Inpatient Sample. Those requiring surgery within 24 hours fo cardiac arrest were excluded. Patients who underwent a cardiac procedure after 5 days of cardiopulmonary resuscitation were classified as Delayed (others: Early). Multivariable regression models were constructed to evaluate associations between delayed timing of surgery with in-hospital mortality, postoperative complications, hospitalization duration, and costs.Results Of an estimated 9,240 patients meeting study criteria, 4,860 (52.6%) received delayed cardiac surgery. Following entropy balancing, delayed surgery was significantly associated with decreased odds of in-hospital mortality (Adjusted Odds Ratio [AOR] 0.75, 95% Confidence Interval [CI] 0.58 - 0.97). However, delayed operation demonstrated greater odds of postoperative thromboembolic (AOR 1.44, 95% CI 1.02 - 2.04), and infectious (AOR 1.65, 95% CI 1.31 - 2.08) complications. Notably, delay did not alter odds of neurologic complication, and was linked to a decrement in per-day costs (beta -$2,100, 95% CI -2,600 - -1,700).Conclusions While preoperative cardiac arrest remains challenging, the present study demonstrates the safety profile of delaying cardiac operation among patients tolerating at least 24 hours of a delay to surgery. Future studies are needed to elucidate the factors associated with favorable outcomes in this population.