Is the Predictive Value of Glasgow Coma Scale Affected by the Timing of Its Measurement in Adult Patients With Traumatic Brain Injury?

Background

Trauma is a critical global public health concern and the number of fatalities as a result of trauma continues to increase globally. In 2016 more than 4,6 million deaths were the result of trauma making it the 8th leading cause of death. In the Global Burden and Disease study (GBD), traumatic injuries account for nearly one-tenth of all deaths, more than malaria, tuberculosis, HIV/AIDS and maternal conditions combined.

TBI is defined as brain injury caused by trauma, trauma being defined as damage inflicted on the body as the direct or indirect result of an external force, with or without disruption of structural continuity. Traumatic brain injury (TBI) is a leading cause of morbidity and mortality globally. It is the largest contributor to trauma deaths in the world, having three times higher mortality rate than trauma without accompanied TBI. It is estimated that TBI affects more than 10 million people annually.

To guide physicians in diagnostics and resuscitation regimes, prognostic models predicting TBI severity and outcome are of great importance. The Glasgow Coma Scale (GCS) is one of the most widely used prognostic model. It is a neurological scale developed to assess the response to stimuli in patients with craniocerebral injuries by using three parameters; eye opening, verbal response and motor response. It has been used to assess level of consciousness in both clinical practice and neurotrauma research. The GCS Score, the sum of the three parameters used in GCS is used to assess severity, ranging from mild, moderate to severe.

Several studies have researched the prognostic value of GCS and the prognostic value of GCS individual components, but little is known about how the relationship of time between injury and first GCS affects the predictive value of GCS. Studies have shown that GCS measured on admission to trauma care is more predictive than GCS measured at the trauma site, and that the median GCS on admission is higher than the median GCS at trauma site but if and how time affects GCS scores has not been studied.