506 Factors associated with appropriate treatment of obstetric hypertensive emergency

Abstract

We aimed to identify factors associated with receiving recommended treatment for obstetric hypertensive emergency. We present a retrospective case-control study of all women who had persistent severe hypertension (≥2 systolic blood pressures (BP) ≥160 mm Hg and/or diastolic BP ≥110 mm Hg within 1 hour of each other) during their delivery hospitalization at a tertiary hospital from 1/2013 to 9/2020. Data were extracted from hospital electronic medical records using standard definitions and billing and diagnosis codes. We defined recommended treatment as administration of intravenous labetalol or hydralazine, or oral immediate-release nifedipine any time after the first or second severe-range BP during their delivery hospitalization. Maternal age, race/ethnicity, marital status, insurance type, pre-pregnancy BMI, smoking status, parity, singleton versus multiple gestation, diabetes (pre-existing or gestational), hypertensive disorders of pregnancy (HDP), time of day (7am-6pm versus 7pm-6am) and day of week (weekday versus weekend) of hypertensive emergencies were compared between women who received recommended treatment and those who never received recommended treatment. Adjusted odds ratios (aOR) and 95% CI were calculated using multivariable regression analysis. Of 39,919 women, 2114 (5.3%) met inclusion criteria. 950 (44.9%) women received recommended treatment, while 1,164 (55%) did not. In the multivariate model, treated women were more likely than untreated women to be Black (aOR 1.51, 95% CI 1.17 – 1.95), have HDP (aOR 6.13, 95% CI 5.02 – 7.49) or have diabetes (aOR 1.45, 95% CI 1.43-1.85). Treatment was less likely if hypertensive emergency occurred overnight (aOR 0.70, 95% CI 0.57-0.86)(Table). Black race, HDP, diabetes, and daytime occurrence were associated with increased likelihood of receiving recommended treatment for obstetric hypertensive emergency. Severe hypertension overnight was associated with a 30% lower odds of receiving treatment, and could serve as a target for measures aimed at improving treatment and reducing maternal morbidity.