Abstract P110: Intravenous Hydralazine Effect On Blood Pressure Following Severe Inpatient Hypertension Development

Abstract

Background: BP elevations in the hospital are commonly treated with intravenous medications, specifically hydralazine. However, treatment guidelines are lacking. Our goal is to assess the effect of intravenous hydralazine on BP following severe inpatient HTN development. Methods: This is a cohort study of adults admitted for reasons other than HTN and developed severe HTN within a single healthcare system. We defined severe inpatient HTN as the first documentation of BP elevation (>180 systolic or >110 diastolic) at least 1 hour after admission. Pregnant women were excluded. Mixed-effects models with nonlinear time trend were used to assess and visualize the time-dependent effect of intravenous hydralazine on BP within 6 hours of BP elevation. Results: Of the 23,147 inpatients who developed severe HTN, 13,753 were untreated and 9,166 were treated of which 12% received intravenous hydralazine. Of the treated and untreated patients, 57 and 46% had a severe MAP reduction (drop ≥30%) (p-value<0.01). Risk factors for severe MAP drop include older age, history of drug and alcohol abuse, and higher BP on admission. Compared to inpatients with severe HTN who did not receive antihypertensives, those treated with intravenous hydralazine had a -12 [-14, -10], -19 [-22, -17], -8[-10, -7] mmHg greater reduction in MAP, SBP, and DBP after adjustment for demographic and clinical characteristics. Moreover, intravenous hydralazine resulted in acute BP reduction ( Figure 1 ). Conclusion: Severe MAP reduction is observed in both treated and untreated inpatients with severe HTN, however adjusted absolute decrease in MAP is greater in inpatients treated with intravenous hydralazine.