Comparison of US and Canadian Perioperative Outcomes and Hospital Efficiency After Total Hip and Knee Arthroplasty.

IMPORTANCE The combination of an aging population, growing number of medical interventions, and surging economic burden of health care has renewed interest in reevaluating and exploring new health care models. OBJECTIVES To compare the performance of the US and Canadian health care systems by assessing major complications following primary total hip arthroplasty (THA) and total knee arthroplasty (TKA) and to measure the efficiency of both health care models by comparing the postoperative length of stay. DESIGN, SETTING, AND PARTICIPANTS With patients grouped according to the country where they underwent surgery, we queried the National Surgical Quality Improvement Program database to identify 55,335 Canadian and US patients who underwent primary elective THA or TKA between January 1, 2011, and December 31, 2012. MAIN OUTCOMES AND MEASURES Differences in patient demographics, as well as the rate of 30-day major complications and length of stay, were compared between patients hospitalized in the United States and Canada. RESULTS Baseline characteristics were similar between the groups. Most US patients underwent general anesthesia (THA, 61.8%; TKA, 59.4%); Canadian patients received more regional anesthesia (THA, 78.7%; TKA, 81.0%). Patients in the United States received more transfusions postoperatively (THA, 9.0% more; TKA, 6.4% more; P < .001) and had shorter hospitalizations (THA, 1.4 days less; TKA, 1.3 days less; P < .001) with a greater proportion of patients discharged to rehabilitation facilities (THA, 21.6% more; TKA, 26.6% more; P < .001). With results reported as incidence rate ratios (95% CIs), after adjusting for all other variables, risk factors, and adverse outcomes, having surgery in Canada increased the postoperative length of stay by 57% (1.57 [1.53-1.61]) for THA and 49% (1.49 [1.46-1.52]) for TKA. With results reported as odds ratios (95% CIs), major complications were significantly more common in Canada following TKA (1.65 [1.31-2.07]) but not THA (1.09 [0.79-1.51]). CONCLUSIONS AND RELEVANCE The rate of major complications was significantly higher in Canada following TKA, but there was no significant difference following THA. Patients undergoing the procedures in US hospitals also had substantially shorter lengths of hospital stay, perhaps reflecting more efficient postoperative care and discharge planning in those facilities.