Toward more rational prediction of outcome in patients with high-grade subarachnoid hemorrhage

OBJECTIVE: Accurate outcome prediction after high-grade subarachnoid hemorr hage remains imprecise. Several clinical grading scares are in common use, but the timing of grading and changes in grade after admission have not bee n carefully evaluated. We hypothesized that these tatter factors could have a significant impact on outcome prediction. METHODS: Fifty-six consecutive patients with altered mental status after su barachnoid hemorrhage, who were managed at a single institution, were studi ed retrospectively. On the basis of prospectively assessed elements of the clinical examination, each patient was graded at admission, at best before treatment, at worst before treatment, immediately before treatment, and at best within 24 hours after treatment of the aneurysm using the Glasgow Coma Scale (GCS), the World Federation of Neurological Surgeons (WFNS) scale, a nd the Hunt and Hess scare. Outcome at 6 months was determined using a modi fication of the Glasgow Outcome Scale validated against the Karnofsky scale . All grades and clinical and radiographic data collected were compared amo ng good and poor outcome groups. Multivariate analyses were then performed to determine which grading scale, which time of grading, and which other fa ctors were correlated with and contributed significantly to outcome predict ion. RESULTS: A good outcome was achieved in 24 (43%) of 56 patients. Our study also had a 32% mortality rate. With the Hunt and Hess scale, only the worst pretreatment grade was significantly correlated with outcome. However, wit h the CCS and the WENS scare, grading at all pretreatment times was signifi cantly correlated with outcome, although outcome was best predicted before treatment, regardless of the scare used, if grading was performed at the pa tient's clinical worst. Multivariate analysis revealed that the best predic tor of outcome was WFNS grade at clinical worst before treatment. Used alon e, a WENS Grade 3 at worst pretreatment predicted a 75% favorable outcome, and a WENS Grade 5 at worst pretreatment predicted an 87% poor outcome. No significant correlation was found between direction or magnitude of change in grade and outcome. Age was found to be significantly correlated with out come, but it was only an independent factor in outcome prediction when used in conjunction with the Hunt and Hess scale and not with the WENS scare an d the GCS. CONCLUSION: Timing of grading is an important factor in outcome prediction that needs to be standardized. This study suggests that the patient's worst clinical grade is most predictive of outcome, especially when the patient is assessed using the WENS scale or the CCS.