Prognostic value and determinants of first-day mean arterial pressure in spontaneous supratentorial intracerebral hemorrhage

Abstract

Background and purpose: The onset of spontaneous intracerebral hemorrhage (ICH) is often accompanied by transient blood pressure (BP) elevation. The prognostic value and the determinants of this BP reaction have not entirely been solved, and the present study was focused on these questions.

Methods: From 1985 to 1991 in Central Finland (population, 246,000), a total of 425 patients had first-ever ICH verified by CT or necropsy. The hematoma was supratentorial in 337 patients. Of the 306 patients with supratentorial ICH who had CT, 282 had the BP measured at least once within 24 hours of onset, and they formed the study population. The case notes and CT films were reviewed, and mean arterial pressure (MAP) was calculated from the highest BP reading.

Results: The fatality rate was high; 43% of the patients were dead within 28 days of onset. Six independent predictors of the 28-day survival were identified by multiple logistic regression; these predictors were consciousness on admission, first-day MAP, subarachnoid spread of the bleed, lateral shift of hemispheral midline structures, admission blood glucose, and vomiting. The MAPs varied between 66.7 and 203.3 mm Hg, and the cutoff points of the MAP quartiles were 118, 132, and 145 mm Hg. Patients in the first three MAP quartiles had relatively fair outcome, with 71%, 65%, and 60%, respectively, alive 28 days after onset. This was in sharp contrast to the fourth quartile, with only 33% surviving the first 28 days (log-rank, P < .0001 to P = .0010). Patients unconscious/ comatose on admission had significantly higher MAPs than did those who were alert or somnolent/disoriented (ANOVA, P = .0079). However, at all levels of consciousness, the 28-day fatality rate increased from the first to the fourth MAP quartile: 69% in the alert, 186% in the somnolent/disoriented, and 45% in the unconscious/comatose patients. Stepwise multiple regression analysis gave four independent predictors of the first-day MAP: hypertension, age (in an inverse fashion), admission blood glucose, and hematoma volume.

Conclusions: The most important predictor of the 28-day survival was the level of consciousness on admission, followed by first-day MAP. Hypertension was the most important predictor of the first-day MAP, followed by age, which had an inverse effect on the MAP level. At all levels of consciousness, high first-day MAP (especially if > 145 mm Hg) worsened the 28-day survival rate.