Hospital variation in mortality from cardiac arrest after cardiac surgery: an opportunity for improvement?

Among all postoperative complications, cardiac arrest after cardiac surgical operations has the greatest association with mortality. However, hospital variation in the ability to rescue after cardiac arrest is unknown. The purpose of this study was to characterize the impact of cardiac arrest on mortality and determine the relative impact of patient, operative, and hospital factors on failure to rescue (FTR) rates and surgical mortality after cardiac arrest.

A total of 79,582 patients underwent operations at 17 different hospitals (2001 through 2011), including 5.2% (n=4,138) with postoperative cardiac arrest. Failure to rescue was defined as mortality after cardiac arrest. Patient risk, operative features, and outcomes were compared among hospitals.

Overall FTR rate was 60% with significant variation among hospitals (range, 50% to 83%; p<0.001). Failure-to-rescue patients were slightly older, presented with increased preoperative risk, and underwent more emergent operations (all p<0.05). After risk adjustment, the variable "individual hospital" demonstrated the strongest association with likelihood for FTR (likelihood ratio=39.1; p<0.001). Overall risk-adjusted mortality, cardiac arrest, and FTR rates varied across hospitals and did not correlate. High-performing hospitals with lowest FTR rates accrued longer postoperative and intensive care unit stays after the index operation (2 to 3 days; p<0.001).

Significant hospital variation exists in cardiac surgical mortality and FTR rates after cardiac arrest. Institutional factors appear to confer the strongest influence on the likelihood for mortality after cardiac arrest compared with patient and operative factors. Identifying best practice patterns at the highest performing centers may serve to improve surgical outcomes after cardiac arrest and improve patient quality.