The Implementation of Centralization for High-risk Surgery-Estimating Potentially Avoidable outcome of cardiac procedure

Background: Volume-outcome research techniques are well-developed, and a great deal of evidence from volume-outcome studies has indicated that surgical volume is negatively associated with adverse healthcare outcomes. Many countries have thus initiated health policies which encourage the centralization of surgery. The goal of these policies is to have patients treated at centralized, high-volume surgical centers which employ highly specialized physicians. As these centers typically have access to abundant medical resources, they can provide optimal care and also improve post-care outcomes. We reviewed the operation and effectiveness of surgery centralization policies in many countries and found that they had a positive impact on health care. In recent years, several studies have also revealed a positive correlation between health outcomes and the volume of specific types of surgeries or procedures in Taiwan. Currently, Taiwan does not have a policy of centralization for high-risk surgeries, and whether such a policy can positively impact the healthcare system in Taiwan has not been confirmed. Therefore, the impact of centralization policies must be further evaluated. Objectives: We sought to estimate how many deaths, unplanned readmissions, and comorbidities could potentially be avoided in Taiwan if a centralization policy was implemented for cardiac procedures. We further examined how a policy which mandated that patients be referred to high-volume hospitals could affect accessibility to care as well as financial losses in low-volume hospitals. Methods: Data were obtained from Taiwan’s National Health Insurance Research Database. Our retrospective cohort design included patients who underwent Percutaneous Transluminal Coronary Angioplasty (PTCA) or Coronary Artery Bypass Grafting (CABG) for the first time between 2010 and 2012. We used multilevel logistic regression and G-computation to examine volume-outcome relationships and to estimate the number of potentially avoidable adverse healthcare outcomes. To examine the effects on patent accessibility to care, we performed geographic variation and used free Open GeoDA software to predict the cross-boundary flow of cardiac procedures (i.e. patients who would be required to visit a high-volume center as a result of centralization policy). Finally, we predicted the impact that surgery centralization would have on inpatient revenue in low-volume hospitals by calculating the ratio of total cardiac procedure inpatient revenue to total hospital inpatient revenue. Results: We found that 29,689 of 92,370 patients who underwent PTCA and 4,150 of 9,530 patients who underwent CABG were admitted to low-volume hospitals between 2010 to 2012. We estimated that centralization of PTCA could reduce the number of deaths by 442 (95% confidence interval [CI]: 274-693), the number of readmissions by 620 (95% CI: 471-776), and the number of comorbidities by 766 (95% CI: 607-921). We further estimated that centralization of CABG could reduce the number of deaths by 127 (95% CI: 72-218), the number of readmissions by 66 (95% CI: 30-125), and the number of comorbidities by 271 (95% CI: 201-299). However, we did not find a significant relationship between hospital volume and 30-day readmission or 30-day comorbidity for CABG in 2010. Considering accessibility to care, 10-12% of patients who underwent PTCA and 18% of patients who underwent CABG had to travel farther to access medical care. Finally, we determined that low-volume hospitals incurred financial losses of approximately 5.5-6.6% and 2%, respectively, by referring PTCA and CABG patients to higher-volume surgical centers. Conclusions: Centralization policies should positively impact healthcare outcomes and only have minor impacts on accessibility to care for patients and minor financial consequences for low-volume hospitals. We therefore suggest that Taiwan consider centralization when developing healthcare-related policies to improve quality of care and the healthcare outcomes for cardiac procedures.