Glasgow Coma Scale expanded to assist in classifying severity and prognosis of brain injury

Posted: 20/08/2018

Anyone familiar with head injuries (or indeed watching TV medical dramas!) will know about the Glasgow Coma Scale (GCS), which is used to assess levels of consciousness after injury or oxygen deprivation. The system has been around since the 1970s and measures the patient in three main respects – eye, motor (movement) and verbal responses to stimuli. The quality of each response is assessed and scored by the attending clinician. The maximum total score is 15/15 – a patient who is fully alert and responsive. The lower the score, the less responsive the patient. GCS scores are frequently used in an initial assessment and then repeated and are a key indicator of the patient’s condition and progression. The system is simple and universally used, meaning all clinicians can carry it out and interpret the findings quickly.

However, one of the original creators of the GCS has been working with colleagues to produce an updated system, recently published and known as the ‘GCS-Pupils’ system (GCS-P). Its aim is to enhance the ability to assess the severity of and prognosis for a brain injury. Decisions about management are influenced by perceptions of the relationship between a patient’s early condition and their likely outcome and so the aim was to improve the accuracy of the assessment carried out in the initial stages in order to predict a likely outcome.

While the original GCS system is a good measure of severity of injury and prognosis, the reactivity of a patient’s pupils is also a key prognostic indicator, so the aim of the new system therefore was to combine the two to get the most accurate assessment possible of level of injury and prognosis. The team felt that this would enhance the ability to manage patients with brain injury, but recognised the importance of keeping any new system simple to use. The other factors considered as relevant to the classification of an injury were age (increasing age at time of injury tending towards worse prognosis) and CT findings. In essence, the GCS assessment is carried out as previously, but the patient’s pupil reactivity is also assessed and graded 0, 1 or 2. This score is then subtracted from the GCS score as poor pupil responsiveness (given a higher score) is an adverse prognostic indicator.

When asked about these important studies, the authors responded: "Decisions about patient care in the immediate aftermath of a head injury are influenced by physician perceptions of the patient's likely outcome, so it's important that assumptions that underlie these decisions are correct. Working together between Glasgow and Edinburgh, we have developed the GCS-P and associated prognostic charts. These simple and easy to use tools provide reliable estimates of outcomes at 6 months and will support clinician decision making in neurotrauma."

Philippa Luscombe, partner in the personal injury team at Penningtons Manches who specialises in cases involving brain injury, comments: “It is well known that the early management of a patient with a head injury can have a significant impact on outcome. Anything that helps attending medics evaluate a patient with a head injury and identify if quick and active management is likely to make a difference can only be a good thing. This assessment may assist in justifying ongoing rehabilitation for patients with serious injuries after acute care (which is an issue we often encounter when acting for clients with head injuries), whose GCS-P is a good prognostic indicator. It should also support the communication and management of expectations for families. The GCS scoring system has been a big success and it will be interesting to see how quickly GCS-P comes into widespread use.”

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