Validation of a new neurological score (FOUR Score) in the assessment of neurosurgical patients with severely impaired consciousness

Background: The Glasgow coma scale (GCS) was introduced as a scoring system for patients with impaired consciousness after traumatic brain injury (TBI). Since, it has become the worldwide standard in TBI assessment. The GCS has repeatedly been criticized for its several failures to reflect verbal reaction in intubated patients, and to test brain stem reflexes. Recently, the full outline of unresponsiveness (FOUR) score was introduced, which is composed of four clinically distinct categories of evaluation: eye reaction, motor function, brainstem reflexes and respiratory pattern. This study aims to validate the FOUR score in neurosurgical patients. Methods: FOUR score and GCS were assessed in a consecutive series of neurosurgical patients with severely impaired consciousness (GCS < 9). Their correlation with the 30-day Glasgow outcome score (GOS) was compared. Patients admitted for TBI, spontaneous intracranial hemorrhage (intracerebral hemorrhage, aneurysmal subarachnoid hemorrhage, cerebellar hemorrhage), or malignant middle cerebral artery infarction were included. Results: We assessed a total of 101 patients (mean age = 64y, SD = 36.1y). The area under the curve (AUC) for mortality was 0.768 (P = 0.0001) for the FOUR Score, and 0.699 (P = 0.001) for the GCS. For poor outcome (GOS = 2-3) the FOUR score AUC was 0.683 (P = 0.018), the GCS AUC was 0.682 (P = 0.019). The FOUR score value for favorable outcome (GOS = 4-5) was 0.748 (P = 0.001), the corresponding GCS value was 0.704 (P = 0.002). Conclusions: The FOUR score was more robust than the GCS in predicting mortality after 30days in neurosurgical patients with severely impaired consciousness. There was no relevant difference in predicting poor and good outcom