Failure to rescue: variation in mortality after cardiac surgery

Measures to prevent surgical complications are critical components of optimal patient care, and adequate management when complications occur is equally crucial in efforts to reduce mortality. This study aims to elucidate clinical realities underlying in-hospital variations in failure to rescue (FTR) after cardiac surgery.

Using a statewide database for a quality improvement program, we identified 62 450 patients who had undergone adult cardiac surgery between 2011 and 2018 in 1 of the 33 Michigan hospitals performing adult cardiac surgery. The hospitals were first divided into tertiles according to their observed to expected (O/E) ratios of 30-day mortality: low-mortality tertile (O/E 0.46-0.78), intermediate-mortality tertile (O/E 0.79-0.90) and high-mortality tertile (O/E 0.98-2.00). We then examined the incidence of 15 significant complications and the rates of death following complications among the 3 groups.

A total of 1418 operative deaths occurred in the entire cohort, a crude mortality rate of 2.3% and varied from 1.3% to 5.9% at the hospital level. The death rates also diverged significantly according to mortality score tertiles, from 1.6% in the low-mortality group to 3.2% in the high-mortality group (P < 0.001). Hospitals ranked in a high- or intermediate-mortality tertile had similar rates of overall complications (21.3% and 20.7%, P = 0.17), while low-mortality hospitals had significantly fewer complications (16.3%) than the other 2 tertiles (P < 0.001). FTR increased in a stepwise manner from low- to high-mortality hospitals (8.3% vs 10.0% vs 12.7%, P < 0.001, respectively). Differences in FTR were related to survival after cardiac arrest, multi-system organ failure, prolonged ventilation, reoperation for bleeding and severe acute kidney disease that requires dialysis.

This study demonstrates that timely recognition and appropriate treatment of complications are as important as preventing complications to further reduce operative mortality in cardiac surgery. FTR tools may provide vital information for quality improvement initiatives.