(446) Strict Blood Pressure Control and Risk of Postpartum Readmission

Objective:
Hypertensive disorders of pregnancy (HDP) comprise approximately 10% of postpartum readmissions. Strict discharge criteria for the delivery encounter are a suggested practice for reduction in HDP-related readmission. We evaluated whether implementation of discharge criteria requiring BP < 150/100 for at least 24 hours reduced the likelihood of postpartum readmission for HDP.

Study Design:
Analysis included live- and stillbirths >/= 20 weeks’ at a single site from 2019-2022. Readmissions included inpatient stays with any hypertension-related primary diagnosis code 1-42 days after discharge. Patients discharged pre-implementation of strict BP discharge criteria, (1/1/19-1/31/22) were compared to those discharged post-implementation (2/1/22-12/31/22). Race and ethnicity were excluded from regression models to avoid conflating the social construct of race with biological contributors to a clinical outcome.

Results:

We reviewed 23,734 deliveries and 358 readmissions. HDP-related readmission rates were 1.4% (N=259) pre-implementation of strict BP discharge criteria, and 2.1% (N=99) post-implementation, p< .0003. Our delivery cohort was racially and ethnically more diverse than the United States’ population, though EMR-reported Black patients were readmitted disproportionately more than others (Tables). The most common readmission diagnosis was severe preeclampsia. Post-implementation of strict BP discharge criteria, a higher proportion of patients (N=307, 6.4%) also presented to triage for HDP issues than pre-implementation (N=1068, 5.7%), p=.0003. The odds ratio (OR) for HDP readmission post-2/1/22 was 1.53 (CI 1.2-1.9, p=.0004). After adjusting for confounders, the OR was 1.48 (CI 1.13-1.92, p =.004).

Conclusion:

HDP readmission risk was higher after implementing strict BP discharge criteria. This may represent more severe disease exacerbations, and strict BP discharge criteria may mitigate risk of unnecessary readmissions. Close outpatient follow-up, remote BP monitoring, and patient education on HDP exacerbation may encourage appropriate presentations to care and prevent out-of-hospital mortality.