A SIMPLE SCORING SYSTEM FOR ACCURATE PREDICTION OF OUTCOME WITHIN 4 DAYS OF A SUBARACHNOID HEMORRHAGE

This study was designed to examine the consistency of a number of easi ly identifiable predictive factors in assessing outcome within four da ys of a subarachnoid haemorrhage. Patients with a proven subarachnoid haemorrhage, aged between 15-65, of any neurological grade who had ble d within 72 hours of admission, and who had undergone a CT scan within 96 hours of the ictus, were included. Three groups of patients were s tudied prospectively. The studies were separated in time and place. Th e series were similar overall but there were some variations between t he three groups of patients because of alterations in referral pattern s and management strategies between the series. There were significant differences in the patients' ages, grades on admission, timing of ang iography, negative angiography rate and timing of operation. This did not affect overall outcome; 57%, 61% and 59% of the patients in series 1, 2 and 3 respectively making a good recovery. The proportion of pat ients with a poor outcome was also similar. To identify the level of r isk of an individual patient within the first few days of haemorrhage, we considered a number of early predicitive factors. Two emerged as s trong predictors of outcome; the early neurological grade and the dist ribution of blood on the CT scan. We developed a simple scoring system from the first series, based on these findings, designed to predict o utcome at three months. The scoring system was calculated on the basis of the distribution of blood seen on the CT scan and the patients' ne urological grade on admission. Two points each were scored for interhe mispheric, intraventricular, basal or intracerebral blood (excluding b lood in the sylvian fissures). Patients in grade 1-3 scored -1, grade 4 scored 0, grades 5 & 6 scored +5. The scan score and grade score wer e summated to give the overall score. Patients were placed in risk gro ups (low, score -1; medium, score 0-2; high, score 3+). The scoring sy stem was then applied prospectively to the two subsequent groups of pa tients. In each of the three series there was a clear correlation betw een the patients' scores and their outcomes but more importantly the p robability of each outcome for each risk group was considered. In both the second and third series the probability of a full recovery in the low risk group was very likely - P = 0.000. In the second series, giv en a high risk category, there some indication that death was the like ly outcome (P = 0.085), while in the third series death was significan tly the most likely outcome (P = 0.001) in the risk category. This stu dy demonstrates that outcome is determined at the time of initial haem orrhage and is reflected by the early neurological grade and the CT di stribution of subarachnoid haemorrhage. Other variables, including age , systemic blood pressure, the use of nimodipine or beta-blockers, and the timing of operation do not alter the risk grouping of patients, i .e., do not move a patient from high to medium or low risk groups.