The frequency and cost of complications associated with coronary artery bypass grafting surgery: Results from the United States Medicare program

Background. We estimate the incremental hospital resource consumption associated with treating selected complications experienced by Medicare beneficiaries undergoing coronary artery bypass grafting (CABG). Methods. This retrospective study, using the Medicare Provider Analysis and Review file, identified 114,233 Medicare beneficiaries who survived CABG without concomitant valve repair during a hospitalization for fiscal year 2005. The frequencies of seven complications were determined: hemorrhage or postoperative shock, reoperation, postoperative adult respiratory distress syndrome, new-onset hemodialysis, postoperative stroke, postoperative infection and septicemia. The observed and adjusted incremental hospital resources consumed (cost and length-of-stay) in treating beneficiaries experiencing each of the selected complications were estimated. Results. The mean cost of a hospitalization associated with a CABG procedure among Medicare beneficiaries was $32,201 +/- $23,059, and the mean length of stay was 9.9 +/- 7.8 days. After adjusting for patient demographics and comorbid conditions, the 13.64% of Medicare beneficiaries experiencing any of the study complications consumed significantly more hospital resources (incremental cost, $15,468) and had a longer length of stay (incremental stay, 5.3 days). Conclusions. Despite ongoing improvements in outcomes, major complications remain common after bypass grafting and add substantially to hospital costs for these procedures. These findings suggest that the potential cost savings of redirecting resources currently spent on treating complications will help make the "business case" for investing in patient safety initiatives and best practices guidelines shown to reduce selected complications.