438: Perinatal outcomes pre- and post-adoption of ACOG Hypertension guidelines for managing preeclampsia with severe features

Abstract

ACOG revised its guidelines for managing preeclampsia with severe features (SPE) in 2013 to recommend expectant management (EM) as opposed to immediate delivery (ID) in appropriate women given evidence that EM improved neonatal outcomes without significant maternal harm. We sought to pragmatically compare maternal and neonatal outcomes in women with SPE before and after implementation of these guidelines. We conducted a retrospective cohort study of all women with SPE delivering non-anomalous live singletons 23- 34 weeks at a single tertiary care center from 2013-2017. Patients were categorized as pre-guideline (1/2013- 12/2015) or post-guideline adoption (1/2016-12/2017 – managed per ACOG guidelines). Primary outcomes included maternal and neonatal composite morbidity; secondary outcomes included composite components (Table), length of stay, birthweight, and delivery gestational age (GA). Groups were compared with Student’s t- test, Chi-square, and Wilcoxon rank sum tests; odds ratios (95% CIs) were calculated and adjusted for covariates. Yearly composite outcome rates were compared using Cochran-Armitage trend test. Subgroup analysis of pre- and post-guideline cohorts excluding women ineligible for EM by ACOG guidelines was planned. We estimated a sample size of 250 per group would provide 80% power at a = 0.05 to detect a 50% reduction in neonatal morbidity from a 21.5% pre-guideline rate. From 2013-2017, 543 women with SPE were identified: 278 (51%) pre-guideline and 265 (49%) post-guideline change. Baseline characteristics were similar between groups except marital status and higher admission blood pressures in the post-guideline group (Table). There were no significant differences in delivery GA, maternal or neonatal composite morbidity between groups (Table). There were no significant differences in composite maternal or neonatal morbidity over time (Figure). Subgroup analysis excluding women ineligible for EM was consistent with the primary analysis. Overall perinatal outcomes were similar before and after implementation of new SPE management guidelines at our institution. Prospective studies are needed to evaluate guideline compliance or if benefits are limited to subsets of this population, e.g. earlier or later GAs.View Large Image Figure ViewerDownload Hi-res image Download (PPT)