The FOUR vs Glasgow Scale for Monitoring the Transition from Acute to Chronic Impairment of Consciousness in the ICU

Introduction. Management of a patient with chronic disorders of consciousness (DOC) requires establishing a correct diagnosis, dynamic assessment, intensive care, and scientifically based prognosis. It is also important to monitor the recovery from coma and the development of chronic DOC. The Glasgow Coma Scale (GCS), a “gold standard” that has been widely used in research and clinical practice for 50 years, has a number of obvious significant drawbacks: brainstem reflexes, eye movements or complex motor responses in patients with altered consciousness are not assessed, which precludes the possibility of reliably assessing the condition of a patient with subtentorial damage and in the state of DOC. In this regard, the FOUR scale has been added to the GCS in recent years, which has the advantages of greater sensitivity to the neurological status in patients with acute cerebral insufficiency (ACI); and due to the high prognostic value of the scale in patients with an unfavorable outcome, it has prospects for continued use in patients with DOC.

Aim of the Study was to study the sensitivity and specificity of the FOUR scale as clinical metrics for assessing chronic DOC.

Material and Methods. This work is a continuation of the study: “FOUR scale as specific clinimetric in intensive care and rehabilitation of patients with acute cerebral insufficiency — FOURACI”. The study cohort included 33 patients over 18 years of age with acute cerebral insufficiency, with further recovery from coma and formation of chronic disorders of consciousness.

Results. FOUR scale has high correlation with CRS-R (p<0.0001, Spearman correlation coefficient r=0.8946), high sensitivity and specificity in predicting outcomes (AUC=0.936). CONCLUSION The high proven correlation with the CRS-R reference standard allows the FOUR scale to be used as an alternative of GCS tool at the time of coma recovery and chronic disorders of consciousness formation. And in case of insufficient experience and/or negative dynamics of the patient’s condition, FOUR can be used as an auxiliary, simpler and less time-consuming scale for dynamic assessment of consciousness. Keywords: GCS, coma, chronic disorders of consciousness, FOUR, CRS-R, Coma Recovery Scale (revised))> < 0.0001, Spearman correlation coefficient r=0.8946), high sensitivity and specificity in predicting outcomes (AUC=0.936).

Conclusion. The high proven correlation with the CRS-R reference standard allows the FOUR scale to be used as an alternative of GCS tool at the time of coma recovery and chronic disorders of consciousness formation. And in case of insufficient experience and/or negative dynamics of the patient’s condition, FOUR can be used as an auxiliary, simpler and less time-consuming scale for dynamic assessment of consciousness.

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