Glasgow Coma Scale in the prediction of outcome after early aneurysm surgery

OBJECTIVE: A prospective study was performed to analyze whether the Glasgow Coma Scale (GCS) was useful in predicting the outcome after early surgical intervention for aneurysmal subarachnoid hemorrhage (SAH). METHODS: In a consecutive series of 765 patients who underwent surgery for aneurysms within 7 days after SAH, the level of consciousness was assessed by the GCS just before surgery and the outcome was graded by the Glasgow Outcome Scale 6 months after surgery. RESULTS: The patient distribution in accordance with the GCS sum scores in descending order from 15 to 3 was as follows: 334, 140, 58, 27, 20, 26, 27, 19, 26, 17, 20, 27, and 24 patients, respectively. In general, the higher the preoperative GCS score was, the better the surgical outcome was. The overall surgical result was significantly correlated with the preoperative GCS score (rs = 0.615, P < 0.001). With respect to the levels that distinguish the outcome along the GCS axis, a significant difference in the outcome was observed only between the GCS scores of 15 and 14 (P < 0.001, Wilcoxon test). CONCLUSION: The GCS proved useful in the preoperative evaluation of patients with SAH, in terms of outcome prediction. It is suggested that the SAH scale proposed by the World Federation of Neurosurgical Societies be reexamined, because differences in outcomes were not clear between the GCS scores of 13 and 12 or between those of 7 and 6, in which Grades III and IV and Grades IV and V are differentiated in the scale, respectively.