Background

Hospitals with safety-net status have been associated with inferior surgical outcomes and higher costs. The mechanism of this discrepancy, however, is not well understood. We hypothesized that discrepant rates of failure to rescue after complications of routine cardiac surgery would explain the observed inferior outcomes at safety-net hospitals.

Methods

The National Inpatient Sample was used to identify adult patients who underwent elective coronary artery bypass grafting and isolated or concomitant valve operations between January 2005 and December 2016. Hospitals were stratified into low-, medium-, or high-burden categories based on the proportion of uninsured or Medicaid patients to emulate safety-net status as defined by the Institute of Medicine. Failure to rescue was defined as mortality after occurrence of neurologic, cardiovascular, respiratory, renal, or infectious complications (major and minor complications). Multivariable regression was used to perform risk-adjusted comparisons of the rate of complications, failures to rescue, and resource use for high-burden hospitals versus low-burden and medium-burden hospitals.

Results

Of an estimated 2,012,104 patients undergoing elective major cardiac operations, 2% died, whereas 36% suffered major and minor complications. Safety-net hospitals had higher odds of failure to rescue after major comorbidity (adjusted odds ratio 1.12, 95% confidence interval 1.01-1.23). Occurrence of major and minor complications at safety-net hospitals was associated with increased costs ($2,480 [95% confidence interval $1,178-$3,935]) compared with low-burden hospitals.

Conclusion

Safety-net hospitals were associated with higher rates of failure to rescue after occurrence of tamponade, septicemia, and respiratory complications. Implementation of care bundles to tackle cardiovascular, respiratory, and renal complications may affect the discrepancy in incidence of and rescue from complications at safety-net institutions.