Association between type of index complication and outcomes after noncardiac surgery

Background: Failure to rescue, or the death of a patient after a surgical complication, largely occurs in patients who develop a cascade of postoperative complications. However, it is unclear whether there are specific types of index complications that are more strongly associated with failure to rescue, additional secondary complications, or other types of postoperative outcomes. This is a national cohort study of veterans who underwent noncardiac surgery at Veterans Affairs hospitals using data from the Veterans Affairs Surgical Quality Improvement Program (January 1, 2016 to September 30, 2021). Index complications were grouped into categories (cardiovascular, venous thromboembolism, pulmonary, bleeding/transfusion, renal, central nervous system, wound, sepsis, Clostridium difficile colitis, graft, or minor [defined as complications having an associated mortality rate <1%]). The association between type of index complication and failure to rescue, secondary complications, reoperation, and postoperative length of stay was evaluated with multivariable, hierarchical regression, and risk of death assessed with shared frailty modeling.

Results: Among 574,195 patients, 5.3% had at least 1 complication (of which 26.1% had secondary complications, and 8.2% had failure to rescue), and 4.5% had a reoperation. Secondary complication (5.0%-61.4%) and failure to rescue (0.8%-34.2%) rates varied by the type of index complication. Relative to index minor complications, index bleeding was most associated with secondary complication (subdistribution hazard ratio 1.4, 95% confidence interval [1.1-1.8]), index cardiac complications were most associated with failure to rescue (odds ratio 45.4 [34.5-59.7]), index graft complications were most associated with reoperation (odds ratio 96.0 [79.5-115.8]), and index pulmonary complications were associated with 2.6 times longer length of stay (incident rate ratio 2.6 [2.6-2.7]). Index cardiac and central nervous system complications were most strongly associated with risk of death (cardiac-hazard ratio 2.45, 95% confidence interval [2.14-2.81]; central nervous system-hazard ratio 1.84 [1.49-2.27]).

Conclusion: Different types of index complications are associated with different outcome profiles. This suggests surgical quality improvement efforts should be tailored not only to the type of index complication to be addressed but also to the desired outcome to improve.