Less incidence of coronary artery disease in general anesthesia compared to spinal–epidural anesthesia after total knee replacement: 90-day follow-up period by a population-based dataset

Total knee replacement (TKR) is an effective and safe procedure. However, large-scale study to compare the incidence of coronary artery disease (CAD) after spinal or epidural anesthesia (SA–EA) or general anesthesia (GA) for TKR has not ever been conducted. To do so, we studied a population-based dataset from the Taiwan National Health Research Institute and hypothesized that the incidence of CAD might be different with regional than with general anesthesia. The risk of CAD-related events during a 90-day follow-up period among patients who received TKR under SA–EA or GA was evaluated in the present study. A total of 1500 patients from the Taiwan National Health Insurance claims database who underwent TKR from January 1, 2004, to December 31, 2006, were allocated into two groups. Group 1 included 1012 patients who received SA–EA during TKR procedure. Group 2 included 488 patients who received GA during this procedure. The number of patients who developed CAD during the 90-day follow-up period was 31 (3.1 %) in group 1 and 6 (1.2 %) in group 2. The Kaplan–Meier survival analysis of IHD-free cumulative survival rate during the 90-day follow-up period for patients who underwent TKR was significantly lower in group 1 than in group 2. The hazard ratio for the occurrence of CAD was 2.80 (95 % CI 1.16–6.78), and the hazard was higher for patients who received SA–EA than for patients who received GA after adjusted potential confounding factors. After the performance of TKR, patients had a potentially increased risk for CAD in SA–EA compared to GA during the 90-day follow-up period.