An analysis of 30-day mortality after weekend <i>versus</i> weekday elective joint arthroplasty in England and Wales: a cohort study using the National Joint Registry Dataset.

Abstract

To investigate whether elective joint arthroplasty performed at the weekend is associated with a different 30-day mortality <i>versus</i> that performed between Monday and Friday. We examined the 30-day cumulative mortality rate (Kaplan-Meier) for all elective hip and knee arthroplasties performed in England and Wales between 1st April 2003 and 31st December 2014, comprising 118 096 episodes undertaken at the weekend and 1 233 882 episodes performed on a weekday. We used Cox proportional-hazards regression models to assess for time-dependent variation and adjusted for identified risk factors for mortality. The cumulative 30-day mortality for hip arthroplasty was 0.15% (95% confidence interval (CI) 0.12 to 0.19) for patients operated on at the weekend versus 0.20% (95% CI 0.19 to 0.21) for patients undergoing surgery during the normal working week. For knee arthroplasty, the cumulative 30-day mortality was 0.14% (95% CI 0.11 to 0.17) for weekend-operated patients versus 0.18% (95% CI 0.17 to 0.19) for weekday-operated patients. These differences were independent of any differences in patient age, gender, American Society of Anaesthesiologists grade, surgeon seniority, surgical and anaesthetic practices, and thromboprophylaxis choice in weekend <i>versus</i> weekday-operated patients. The 30-day mortality rate after elective joint arthroplasty is low. Surgery performed at the weekend is associated with lower post-operative mortality <i>versus</i> operations performed on a weekday. Cite this article: <i>Bone Joint J</i> 2017;99-B:1618-28.