Interventions for deliberately altering blood pressure in acute stroke

Abstract

Background: It is unclear whether hypertension should be treated after acute stroke, and some have hypothesised that blood pressure should be increased to improve cerebral perfusion.

Objectives: The objective of this review was to assess the effect of lowering or elevating blood pressure in people with acute stroke, and the effect of different vasoactive drugs on blood pressure in acute stroke.

Search strategy: We searched the Cochrane Stroke Group trials register, the Ottawa Stroke Trials Registry (1994), Medline (from 1965), Embase (from 1981), ISI, and existing review articles. We contacted researchers in the field and pharmaceutical companies.

Selection criteria: Randomised trials of interventions that aimed to alter blood pressure in patients within two weeks of acute ischaemic or haemorrhagic stroke.

Data collection and analysis: Two reviewers independently applied the inclusion criteria and assessed trial quality. Two reviewers extracted the data.

Main results: Three trials involving 133 people were included. The trials tested the following vasodilators: nimodipine (66 people), nicardipine (five people), captopril (three people) and clonidine (two people). Oral calcium channel blockers (nimodipine, nicardipine) reduced systolic blood pressure (weighted mean difference 10.9mmHg, 95% confidence interval 2.0 to 19.7), diastolic blood pressure (weighted mean difference 9.5mmHg, 95% confidence interval 4.0 to 15.1) and heart rate (weighted mean difference 4.7 beats per minute, 95% confidence interval 0.2 to 9.2) at 48 hours. The greatest fall in blood pressure over the first 24 hours was shown in patients given the highest dose of nimodipine. The relationship between change in blood pressure and clinical outcome was not clear. There was not enough information to assess the effect of drugs other than calcium channel blockers. No studies of interventions to raise blood pressure were found.

Reviewer's conclusions: There is not enough evidence to evaluate the effect of altering blood pressure after acute stroke. Although oral calcium channel blockers appear to reduce blood pressure following acute stroke, the balance of benefit and risk remains unclear.