Abstract 3093: Clinical Factors Associated With Hypotension Within 12 Hours Of Antihypertensive Therapy In Ed Stroke Patients

Abstract

Background: Extremes of blood pressure (BP) have been associated with poor outcomes in acute stroke. Aggressive antihypertensive therapy in stroke patients with elevated blood pressure (BP) can lead to undesired hypotension. We sought to determine whether any pre-treatment factors are associated with undesired hypotension within 12 hours of initiating antihypertensive therapy in emergency department (ED) patients with neurological emergencies. Methods: This was a secondary analysis of an observational study conducted at an urban academic ED and two community EDs between November 2007 and March 2009. Patients with signs or symptoms of neurological emergencies treated with antihypertensives in the ED were eligible for enrollment if they were not enrolled in interventional clinical trials. Demographics, medical history, antihypertensive use, and BP measurements were abstracted in duplicate. Discrepant data were adjudicated by a third investigator. Based on American Heart Association guidelines, target BP was defined as a 20% reduction in systolic BP from that recorded immediately prior to treatment. Hypotension was defined as a systolic BP drop of > 40% from the pre-treatment level or systolic BP <100mmHg within 12hours of initiation of antihypertensives. Univariable Cox regression was used to evaluate factors associated with early hypotension. Results: One hundred patients were enrolled. Median age was 62years (range 36-96), 50 were male and 53 were black. The most common diagnoses were intracerebral hemorrhage (n=36), ischemic stroke (n=35) and hypertensive emergency (n=10). Hypotension occurred in 28 patients within 12hours of initiation of antihypertensive therapy. Median time from first treatment to hypotension was 211 minutes (range 2-629, IQR 98-355). In univariable analysis, lower baseline GCS and higher baseline BP were associated with post-treatment hypotension ( Table ). Conclusions: In this observational study, hypotension occurred frequently in ED patients with neurological emergencies who received antihypertensives. Since sicker patients with higher BP were more likely to become hypotensive, overly aggressive treatment in these patients may have accounted for the hypotension observed. Larger, future studies should see if these patients are indeed treated more aggressively. Table. Univariate predictors of hypotension