The Role of Hypotension in Secondary Brain Injury after Intracerebral Hemorrhage
Objective: Hypotension is known to exacerbate secondary brain injury and worsen outcome after head trauma and ischemic stroke. Optimal blood pressure management after spontaneous intracerebral hemorrhage (ICH) remains a point of debate. The purpose of this study was to determine the incidence and impact on outcome of hypotension early after ICH. Methods: Medical records were reviewed for all 89 patients admitted with acute non-traumatic ICH to the University of California, San Francisco and San Francisco General Hospital during 1997. Complete information was available in 75 patients, who formed the cohort for analysis. Occurrences of hypotension (defined as a mean arterial pressure (MAP) < 90 mmHg for greater than five minutes) were identified for the first 72 hours after emergency department presentation. Additional characteristics including ICH volume, Glasgow Coma Scale (GCS) score on presentation, and presence of intraventricular hemorrhage (IVH) were also recorded. Outcome was assessed as 30-day mortality. Results: Overall 30-day mortality was 49% (37 of 75). 30-day mortality was 57% for patients with at least one episode of hypotension during the first 3 days (n=47) compared with 36% of patients with no hypotensive episodes (n=28). Patients with a total duration of hypotension > 60 minutes during the first 3 days had a 30-day mortality rate of 61% (n=38) compared with a 30-day mortality rate of 38% in those with < 60 minutes of total hypotension (n=37) (P<0.05). In multivariate regression analysis, GCS score (P<0.001), ICH volume (P=0.05,) and IVH (P=0.04), but not occurrence or duration of hypotension, were independent predictors of 30-day mortality. Conclusions: Hypotension is common within the first several days after acute ICH and is associated with worsened 30-day mortality, especially when present for a total duration > 60 minutes. While blood pressure management after ICH is largely focused on management of hypertension, this suggests that low blood pressure negatively impacts on outcome. Whether hypotension after ICH creates secondary ischemic brain injury or is merely a secondary occurrence in severely affected patients remains to be clarified.