Abstract 12605: Center Variability in Timing of Stage 2 Palliation and Association With Interstage Mortality: A Report From the National Pediatric Cardiology Quality Improvement Collaborative

Abstract

Introduction: The interstage period from discharge following stage 1 palliation (S1P) until stage 2 palliation (S2P) remains high risk. Significant variability between institutions exists around the timing of S2P. We sought to describe the variability in a multi-institution cohort and assess its association with interstage mortality. Methods: The National Pediatric Cardiology Quality Improvement Collaborative registry, with data from 52 centers, was queried. Patients undergoing a hybrid S1P, transplanted prior to S2P, lost to follow up prior to S2P or deemed not candidates for S2P were excluded. Only centers with 10 or greater patients meeting eligibility were included to reduce the impact of outliers. Centers were divided based on median age at S2P into early (n=15) and late (n=16) centers using a cutoff of 153 days. Groups were compared using Chi-squared or Wilcoxon rank sum test. Results: The final cohort included 789 patients from 31 centers. Center specific median age at S2P varied from 109 to 214 days, with a center mean of 158 ± 27 days. At S1P, the late centers had a higher prevalence of preoperative ventilation (34.7% vs. 26.9%, p=0.02) and longer average post-S1P duration of intubation (14.4 ± 19.7 vs. 10.2 ± 11.4 days, p<0.001) and S1P hospital length of stay (48.5 ± 30.4 vs. 38.5 ± 22.3 days, p<0.0001). Interstage mortality was significantly higher in centers performing late vs. early S2P (9.9% vs. 5.7%, p=0.03). Interstage event rate (late: 8.2 vs. early: 5.8 deaths per 10000 interstage days) was not different by group (p=0.26), but interstage duration was significantly longer (133.9 ± 71.5 vs. 103.4 ± 37.8 days, p<0.0001) in the late group. Survival to hospital discharge (98.9% in both groups, p>0.98) and hospital length of stay following S2P (late: 15.6 ± 22.3 vs. early: 13.7 ± 22.4, p=0.68) were similar between groups. Conclusions: In a large multi-institution collaborative, the median age at S2P varies between centers. Centers performing S2P at a later median age have higher interstage mortality. This may be in part due to a higher severity of illness, reflected by higher S1P morbidity in this group. Although optimal timing of S2P remains unclear, centers performing early S2P did not experience worse S2P outcomes, and experienced less interstage mortality.