Effectiveness of extended postpartum inpatient monitoring for hypertensive disorders of pregnancy to reduce the risk of readmission for preeclampsia with severe features

Abstract

Background: Preeclampsia is an obstetrical disorder, which complicates 3% to 6% of pregnancies and contributes to 21.6% of readmissions in the postpartum period. The optimal strategy for inpatient monitoring of blood pressures to minimize readmissions for postpartum patients with hypertensive disorders is not known. We hypothesized that extended monitoring of postpartum patients with hypertensive disorders of pregnancy for at least 36 hours after the last blood pressure that was ≥150/100 mm Hg would result in decreased readmission rates for preeclampsia with severe features compared with those who were not observed by these blood pressure goals.

Objective: This study aimed to evaluate whether extended inpatient monitoring of postpartum patients with hypertensive disorders of pregnancy for at least 36 hours after their last blood pressure that was ≥150/100 mm Hg would improve readmission rates for preeclampsia with severe features within 6 weeks of delivery.

Study design: This was a retrospective cohort study in patients with a singleton pregnancy and a diagnosis of a hypertensive disorder of pregnancy at their delivery admission or at any point during pregnancy who delivered 1 year before and 1 year after the implementation of extended inpatient monitoring of postpartum hypertension. The primary outcome was readmission for preeclampsia with severe features within 6 weeks of delivery. The secondary outcomes were length of stay during first admission, number of readmissions for any indication, intensive care unit admission, postpartum day at readmission, median systolic blood pressure in the 24-hour period before discharge, median diastolic blood pressure in the 24-hour period before discharge, intravenous antihypertensive medication required during first admission, and intravenous antihypertensive medication required during second admission. Univariable analysis was performed for the association between baseline maternal characteristics and the primary outcome. Multivariable analysis was performed, adjusting for baseline maternal characteristic differences between exposure groups.

Results: A total of 567 patients met the inclusion criteria of which 248 patients delivered before and 319 delivered after the implementation of extended monitoring. For baseline characteristics, the extended monitoring group had a significantly higher proportion of patients who were non-Hispanic Black and Hispanic, more diagnoses of hypertensive disorders and/or diabetes mellitus at the time of admission for delivery, a difference in the distribution of hypertensive diagnoses at the time of discharge from the first admission, and fewer discharged patients from their first admission on labetalol than the preintervention group. In a univariable analysis of the primary outcome, there was a significantly increased risk of readmission for preeclampsia with severe features in the extended monitoring group (62.5% vs 96.2% of total readmissions; P=.004). In multivariable analysis, patients in the extended monitoring group were more likely to be readmitted for preeclampsia with severe features than patients in the preintervention group (adjusted odds ratio, 3.45; 95% confidence interval, 1.03-11.5; P=.044).

Conclusion: Extended monitoring with a strict blood pressure goal of <150/<100 mm Hg did not decrease readmissions for preeclampsia with severe features in patients with a previous diagnosis of a hypertensive disorder of pregnancy.

Keywords: extended monitoring; hypertensive disorders of pregnancy; length of stay; postpartum hypertension; postpartum preeclampsia; preeclampsia with severe features; readmission for preeclampsia with severe features.