What are the criteria for using the Glasgow Coma Scale (GCS)?

From the Guidelines

The Glasgow Coma Scale (GCS) should be used to assess the severity of traumatic brain injury, specifically the motor response, as well as pupillary size and reactivity, as recommended by the most recent and highest quality study 1.

Criteria for Using Glasgow Coma Scale

The GCS evaluates three components: eye opening (scored 1-4), verbal response (scored 1-5), and motor response (scored 1-6), with a total score ranging from 3 (deep coma) to 15 (fully alert) 1.

• The scale should be applied when evaluating patients with traumatic brain injury, stroke, drug overdose, metabolic encephalopathy, or any condition affecting consciousness.
• For proper assessment, establish a baseline measurement and then perform serial evaluations at regular intervals to detect changes in neurological status.
• When using the GCS, always test the best response the patient can achieve and document each component score separately along with the total.

Limitations and Considerations

• Limitations include difficulty in assessment when patients are intubated, have facial trauma, or are under the influence of sedatives or paralytics.
• In these cases, document the circumstances affecting the assessment.
• The GCS provides an objective measure that helps standardize neurological assessment across different healthcare providers and guides clinical decision-making regarding the need for intervention, imaging, or intensive care monitoring 1.

Clinical Application

• The GCS is most valuable when tracking trends over time rather than relying on a single measurement.
• Serial GCS scores are quite valuable in patients with mild TBI, as a low GCS score that remains low or a high GCS score that decreases predicts a poorer outcome than a high GCS score that remains high or a low GCS score that progressively improves 1.

From the Research

Criteria for Using Glasgow Coma Scale

The Glasgow Coma Scale (GCS) is a neurological scale used to assess the level of consciousness in patients, particularly those with head injuries. The criteria for using GCS include:

• Evaluating prognosis in head-injured patients 2
• Comparing different groups of patients 2
• Monitoring neurological status 2, 3
• Assessing patients with severe head injuries, particularly those with GCS scores of 8 or less 4
• Predicting mortality and functional outcome in head-injured patients 5

Limitations and Considerations

When using the GCS, several limitations and considerations should be taken into account, including:

• Skewness toward the motor subscore 2
• Experience of the raters 2
• Process of intubation 2
• Time and setting of rating 2
• Nonlinear relationship between GCS score and mortality 5
• Variability in mortality rates and functional outcomes at all scores 5

Specific Patient Groups

The GCS can be used to assess specific patient groups, such as:

• Patients with severe diffuse brain swelling and recent clinical signs of impending brain death, particularly those with GCS scores of 3 and bilateral abnormal pupillary widening 6
• Patients with head injuries who require intracranial monitoring and mannitol administration 4