The Effects of Nighttime Surgery on Outcomes Following Orthotopic Heart Transplantation: An Analysis of the UNOS Database

Abstract

<h3>Purpose</h3> The purpose of the present study is to examine the effect of operative time of day on outcomes in orthotopic heart transplant (OHT) recipients. We hypothesized that nighttime OHT operations would be associated with increased 1-year mortality when compared to daytime OHT operations. <h3>Methods</h3> We performed a retrospective analysis of adult heart transplant recipients in the United Network for Organ Sharing (UNOS) database from January 2000 to December 2019. Operative time of day was derived from the donor cross-clamp time (night, 6 pm-4 am; day, 4 am-6 pm). The primary outcome was survival at 1 year. Kaplan-Meier curves and log-rank statistics were generated to compare the effect of operative time and were further stratified by age, transplant center yearly volume (low volume, < 10; high volume, ≥10), and VAD status at transplant. <h3>Results</h3> Of the 42,007 patients included in the study, 24,200 (57.6%) underwent nighttime and 17,807 (42.4%) daytime OHT (Table 1). Preoperative patient characteristics were similar between cohorts. 1-year survival (Figures 1) was not different between the cohorts (89.7 vs 89.5%, p=0.630). When further stratified by age, center volume, or VAD status, 1-year survival between operative times still remained insignificant. <h3>Conclusion</h3> There is no significant association between nighttime operations and 1-year post-transplant survival in adult heart transplant recipients.