A case-cohort study of postoperative myocardial infarction: impact of anemia and cardioprotective medications.

OBJECTIVE: Postoperative myocardial infarction (poMI) is a serious and costly complication. Multiple risk factors for poMI are known, but the effect of anemia and cardioprotective medications have not been defined in real-world surgical practice. METHODS: Patients undergoing inpatient elective surgery were assessed at 17 hospitals from 2008 to 2011 for the occurrence of poMI (American Heart Association definition). Non-MI control patients were chosen randomly on the basis of case type. Descriptive, univariable, and multivariable statistical analysis were performed for primary outcomes of poMI and death at 30 days. RESULTS: Compared with controls (N = 304), patients with poMI (N = 222) were older (72 ± 11 vs 60 ± 17 years, P < .0001), had a lesser preoperative hematocrit (37 ± 6 vs 39 ± 5, P < .0001), more often were smokers, had a preoperative T-wave abnormality (21% vs 9%, P < .0001), and had a preoperative stress test with a fixed deficit (26% vs 3%; P < .001). Preoperative factors associated with poMI included peripheral vascular disease (odds ratio 2.6; 95% confidence interval 1.3-5.3), tobacco use (1.7; 1.01-2.9), history of percutaneous coronary angioplasty (2.8; 1.6-5.0), and age (1.05; 1.03-1.07), whereas hematocrit >35 (0.51; 0.32-0.82) and preoperative acetylsalicylic acid, ie, aspirin (0.59; 0.4-0.97) were protective. Preoperative ß-blockade, statin, and use of angiotensin-converting enzyme inhibitors were not associated with lesser rates of poMI. Non-MI complication rates were 23-fold greater in the poMI group compared with the control group (P < .0001). Mortality with poMI within 30 days was 11% compared with 0.3% in non-MI control patients (P < .0001). In patients with poMI, factors independently associated with death included use of epidurals (3.5; 1.07-11.4) and bleeding (4.2; 1.1-16), whereas preoperative use of aspirin (0.29; 0.1-0.88), and postoperative ß-blockade (0.18; 0.05-0.63) were protective. Cardiac catheterization, percutaneous coronary intervention, or coronary artery bypass grafting after poMI was performed in 34% of those alive and 20% of those who died (P = .16). CONCLUSION: In the current era, poMI patients have a markedly increased risk of death. This risk is decreased with preoperative use of acetylsalicylic acid and post MI ß-blockade. Further study is warranted to explore the role of anemia and cardiac interventions after poMI.

Assessing the quality of surgical care.

Because of better educated patients, more demanding payers, and regulatory agencies, safety and quality have become prominent criteria for evaluating surgical care. Providers are increasingly asked to document these areas, and patients are using this documentation to select surgeons and hospitals. Payers are using the data to direct patients to providers, and potentially to adjust reimbursement rates. Therefore, health care policy makers, health service researchers, and others are aggressively developing and implementing quality indicators for surgical practice. Given the complex interplay of structure, process, and outcomes, assessment of surgical quality presents a daunting task. We must firmly establish the links between these elements to validate current and future metrics, while engendering "buy-in'' on the part of surgeons.

Comparison of risk-adjusted 30-day postoperative mortality and morbidity in Department of Veterans Affairs hospitals and selected university medical centers: general surgical operations in women.

BACKGROUND: In 1985, Congress mandated that the Department of Veterans Affairs (VA) compare its risk-adjusted surgical results with those in the private sector. The National Surgical Quality Improvement Program was developed as a result, in the VA system, and subsequently trialed in 14 university medical centers in the private sector. This report examines the results of the comparison between patient characteristics and outcomes of female general surgical patients in the two health care environments. STUDY DESIGN: Preoperative patient characteristics and laboratory variables, operative variables, and unadjusted postoperative outcomes were compared between VA and the private sector populations. In addition, stepwise logistic regression models were developed for 30-day postoperative mortality and morbidity. Finally, the effect of being treated in a VA or private sector hospital was assessed by adding an indicator variable to the models and testing it for statistical significance. RESULTS: Data from 5,157 female general surgical VA patients who underwent eligible procedures were compared with those from 27,467 patients in the private sector. Unadjusted 30-day mortality was virtually identical in the two groups (1.3%). The unadjusted morbidity rate was slightly, but notably, higher in the private sector (10.9%) as compared with that observed in the VA (8.5%, p < 0.0001). Predictive models were generated for mortality and morbidity combining both groups; top variables in these models were similar to those described previously in the National Surgical Quality Improvement Program. The indicator variable for system of care (VA versus private sector) was not statistically significant in the mortality model, but substantially favored the VA in the morbidity model (odds ratio=0.80, 95% CI=0.71, 0.90). CONCLUSIONS: The data demonstrate that in female general surgical patients, risk-adjusted mortality rates are comparable in the VA and the private sector, but risk-adjusted morbidity is higher in the private sector. Rates of urinary tract infections in the two populations may account for much of the latter difference.

Evaluating alternative risk-adjustment strategies for surgery.

BACKGROUND: Comparison of institutional health care outcomes requires risk adjustment. Risk-adjustment methodology may influence the results of such comparisons. METHODS: We compared 3 risk-adjustment methodologies used to assess the quality of surgical care. Nurse reviewers abstracted data from a continuous sample of 2,167 surgical patients at 3 academic institutions. One risk adjustor was based on medical record data (National Surgical Quality Improvement Program [NSQIP]) whereas the other 2, the DxCG and Charlson Comorbidity Index (CCI), primarily used International Classification of Disease-9 (ICD-9) codes. Risk-assessment scores from the 3 systems were compared with each other and with mortality. RESULTS: Substantial disagreement was found in the risk assessment calculated by the 3 methodologies. Although there was a weak association between the CCI and DxCG, neither correlated well with the NSQIP. The NSQIP was best able to predict mortality, followed by the DxCG and CCI. CONCLUSION: In surgical patients, different risk-adjustment methodologies afford divergent estimates of mortality risk.