Validation of a new coma scale: The FOUR score

Abstract

The Glasgow Coma Scale (GCS) has been widely adopted. Failure to assess the verbal score in intubated patients and the inability to test brainstem reflexes are shortcomings. We devised a new coma score, the FOUR (Full Outline of UnResponsiveness) score. It consists of four components (eye, motor, brainstem, and respiration), and each component has a maximal score of 4. We prospectively studied the FOUR score in 120 intensive care unit patients and compared it with the GCS score using neuroscience nurses, neurology residents, and neurointensivists. We found that the interrater reliability was excellent with the FOUR score (kappa(w) = 0.82) and good to excellent for physician rater pairs. The agreement among raters was similar with the GCS (kappa(w) = 0.82). Patients with the lowest GCS score could be further distinguished using the FOUR score. We conclude that the agreement among raters was good to excellent. The FOUR score provides greater neurological detail than the GCS, recognizes a locked-in syndrome, and is superior to the GCS due to the availability of brainstem reflexes, breathing patterns, and the ability to recognize different stages of herniation. The probability of in-hospital mortality was higher for the lowest total FOUR score when compared with the lowest total GCS score.

The Glasgow Coma Scale: time for critical reappraisal?

“…8 However, the Glasgow Coma Scale does not test for eye tracking (which has been shown to be best assessed by presentation of a moving mirror). 9 The scale Full Outline of UnResponsiveness (FOUR; an acronym for the number of components tested: eye, motor, brainstem, and respiratory function, and for the maximum score assigned to each of these components) 10 assesses visual tracking explicitly and so can identify patients in a minimally conscious state MINUS who have non-verbal signs of consciousness not detected by the Glasgow Coma Scale (a diagnostic error rate we estimate at 10% in our intensive care population of patients with acute brain injury). 11 In addition, FOUR also tests specifi cally for eye movements or blinking to command (requesting to open the eyes manually if closed), permitting the early detection of locked-in syndrome.…”

The FOUR score: is it just another new coma scale?

“…The Glasgow Coma Scale (GCS) has become the gold standard in clinical practice despite criticism in recent publications about its inconsistent inter-observer agreement, difficulties in evaluating the verbal component in dysphasic (or when encountering ''language barriers'') and intubated patients, and inaccuracy in prognosis [3][4][5][6]. A new coma scale, the Full Outline Of Unresponsiveness (FOUR) score, is gradually gaining acceptance because of an excellent inter-rater agreement, greater neurologic information, and a high predictive value [3,5,9,[12][13][14][15].…”

“…A new coma scale, the Full Outline Of Unresponsiveness (FOUR) score, is gradually gaining acceptance because of an excellent inter-rater agreement, greater neurologic information, and a high predictive value [3,5,9,[12][13][14][15]. It quantifies consciousness by examining eye and motor responses, brainstem reflexes, and breathing pattern (each with a maximal value of 4).…”

“…It quantifies consciousness by examining eye and motor responses, brainstem reflexes, and breathing pattern (each with a maximal value of 4). The FOUR score is appropriate for endotracheally intubated patients, helps to recognize patients with a ''locked-in syndrome'' mimicking coma, identifies patients in a vegetative state or in different stages of brain herniation, and forces one to rule out brain death in those with the lowest score (score of 0: absent eye and motor responses, absence of brainstem reflexes and no respiratory drive) [3].…”

“…Therefore, it seems that for doctors involved in acute care (ED, ICU, stroke Unit, etc.) the FOUR score may be a preferred option for its higher predictive value, reliability, and greater neurological detail [3,[7][8][9][10][11][12][13][14][15]. Likewise, Marcati et al [9] point out that, among patients with the most severe brain injuries (GCS 3-5), the FOUR score provides more neurological data than the GCS.…”