Blood pressure during the first minutes of focal cerebral ischemia

To determine whether blood pressure declines spontaneously during the first minutes and hours of focal cerebral ischemia.

Multiple blood pressure measurements as part of an urgent stroke therapy trial (treatment within 90 minutes of stroke onset).

Thirteen hospitals in three metropolitan communities.

Sixty-nine patients (mean age, 65 +/- 9 years) with acute ischemic stroke who were participants in a phase I urgent stroke therapy trial of recombinant tissue plasminogen activator.

Blood pressures recorded at the scene of stroke by life-squad personnel, in the emergency department, and in the ICU.

The mean time from stroke onset to the time of first blood pressure measurement was 19 +/- 13 minutes. Twenty-four of the 69 patients in the urgent stroke therapy trial had an initial systolic blood pressure of at least 160 mm Hg. Of these, 23 had a significant decline in systolic and diastolic blood pressure during the first 90 minutes after the onset of stroke (mean change in systolic pressure, -29 +/- 22 mm Hg, P < .001; mean change in diastolic pressure, -10 +/- 14 mm Hg, P < .01). No patients received antihypertensive therapy during the time in which the decline in blood pressure was noted.

Mildly or moderately elevated blood pressure frequently declines spontaneously during the first minutes and hours of focal cerebral ischemia and generally does not require urgent pharmacologic treatment.