From the Guidelines
The voice component of the Glasgow Coma Scale (GCS) should be assessed by evaluating a patient's verbal response, with scores ranging from 1 to 5, while considering the effects of sedation and neuromuscular blockade on the assessment 1. To properly assess this component, first attempt to engage the patient in conversation by asking simple questions like their name or current location. Score the response as follows: 5 points for oriented responses (patient knows who they are, where they are, and the current time); 4 points for confused conversation (patient responds coherently but is disoriented); 3 points for inappropriate words (random or exclamatory speech); 2 points for incomprehensible sounds (moaning or groaning); and 1 point for no verbal response. For intubated patients who cannot speak, document this with a "T" (e.g., GCS 10T) rather than automatically assigning a score of 1, as recommended by the consensus summary statement of the international multidisciplinary consensus conference on multimodality monitoring in neurocritical care 1. When assessing non-English speakers, use an interpreter if possible or note language barriers in your documentation. The voice component helps evaluate higher cortical function and can indicate the location and severity of brain injury, with changes in verbal response often being early indicators of neurological deterioration, as supported by the study on clinical policy for neuroimaging and decision-making in adult mild traumatic brain injury in the acute setting 1. Always assess the voice component alongside the eye and motor components for a complete GCS evaluation, considering the inter-rater reliability assessments of the GCS and its strong prognostic marker and indicator of need for surgery in traumatic brain injury (TBI) 1. It is essential to note that the GCS is disadvantaged by the confounders produced by endotracheal intubation and the lack of measurement of pupillary responses, which are strong predictors of outcome, but the prognostic information provided by pupillary responses can be integrated with the GCS to provide greater specificity of outcome prediction 1.
From the Research
Assessing the Voice Component of the Glasgow Coma Scale (GCS)
- The Glasgow Coma Scale (GCS) is a widely used tool for assessing the level of consciousness in patients with neurological conditions 2, 3.
- The GCS includes three components: eye opening, verbal response, and motor response, with the verbal response being a crucial aspect of assessing a patient's level of consciousness 3.
- However, the GCS has been criticized for its limitations, including its failure to incorporate brainstem reflexes and its numerical skew toward the motor response 3.
- In intubated patients, the GCS may not be entirely accurate, as the verbal response component cannot be assessed 4, 5.
- Alternative scales, such as the Full Outline of Unresponsiveness (FOUR) score, have been proposed as more accurate and practical in intubated patients, particularly in predicting early mortality 4.
- Studies have shown that the FOUR score may be more effective in predicting outcomes in intubated patients with traumatic brain injuries compared to the GCS 4.
- The use of the GCS in acute non-traumatic poisoning has also been evaluated, with findings suggesting that a nuanced approach to airway management is warranted, taking into account individual patient needs 5.
- Recent research has highlighted the need for tailored practice management guidelines for intubation thresholds in patients with traumatic brain injury, with a GCS threshold of ≤5 potentially conferring an additional benefit in disposition without worsened outcomes 6.