The Glasgow Coma Scale: A Guide for Nurses

The Glasgow Coma Scale (GCS) is a widely used tool in healthcare for assessing a patient’s level of consciousness. For nurses, understanding and properly applying the GCS is essential in managing patients with head injuries, neurological conditions, or altered levels of consciousness due to various causes. In this article, we will break down the Glasgow Coma Scale, explaining its components, usage, and importance in nursing practice.

What is the Glasgow Coma Scale?

Developed in 1974 by neurosurgeons Graham Teasdale and Bryan Jennett, the GCS provides a standardized method for assessing a patient’s neurological status. The scale evaluates three main areas of responsiveness:

1. Eye Opening (E)
2. Verbal Response (V)
3. Motor Response (M)

Each of these categories is scored, and the sum of the scores indicates the patient’s level of consciousness, ranging from 3 (deep coma or death) to 15 (fully alert).

Components of the GCS

1. Eye Opening (E)
   • 4: Spontaneous – Eyes open without stimulation.
   • 3: To verbal command – Eyes open in response to voice.
   • 2: To pain – Eyes open only in response to painful stimuli.
   • 1: No eye opening – No response to pain or other stimuli.
2. Verbal Response (V)
   • 5: Oriented – The patient can answer questions correctly (e.g., name, date, location).
   • 4: Confused – The patient is speaking but may not be coherent or confused about details.
   • 3: Inappropriate words – The patient speaks random or inappropriate words.
   • 2: Incomprehensible sounds – The patient makes moaning or other unintelligible sounds.
   • 1: No verbal response – The patient is mute, even to painful stimuli.
3. Motor Response (M)
   • 6: Obeys commands – The patient follows simple instructions (e.g., “move your arm”).
   • 5: Localizes pain – The patient attempts to remove a source of pain (e.g., pushing away pressure).
   • 4: Withdraws from pain – The patient pulls away from painful stimuli.
   • 3: Abnormal flexion (decorticate posture) – The patient’s arms flex inward in response to pain.
   • 2: Abnormal extension (decerebrate posture) – The patient’s arms extend rigidly in response to pain.
   • 1: No motor response – The patient does not move, even to painful stimuli.

Interpreting the GCS Score

• GCS 13-15: Mild brain injury or consciousness impairment.
• GCS 9-12: Moderate brain injury.
• GCS ≤ 8: Severe brain injury or coma.

A total score of 8 or below often indicates that the patient is in a coma, and immediate intervention may be necessary to secure the airway and prevent further deterioration.

The Role of Nurses in GCS Assessment

For nurses, GCS assessment is a crucial part of neurological examinations, especially in the intensive care unit (ICU), emergency room, and trauma settings. Regular and accurate GCS scoring allows for early detection of deterioration in a patient’s neurological status, leading to timely interventions.

Key Points for Nurses:

1. Consistency is key: Always apply the same level of stimulus when testing for responses to ensure consistent results.
2. Use appropriate stimuli: For motor and eye response, apply verbal commands first before resorting to painful stimuli.
3. Record the scores accurately: Note down both the component scores (E, V, M) and the total score. For example, record a GCS of 12 as “GCS 12 (E4, V3, M5)”.
4. Frequent reassessment: In critical cases, reassess the GCS frequently to monitor changes, especially if the patient’s condition fluctuates.

Challenges in GCS Application

• Intubated patients: Patients on mechanical ventilation may not be able to respond verbally, making it impossible to score the verbal component. In such cases, the verbal score is marked as “1” or “T” (for “tube”), and the total score is adjusted accordingly.
• Sedated patients: Sedation or medications can affect GCS scoring, leading to an underestimation of consciousness. It is essential to consider drug effects when interpreting GCS.
• Pediatric patients: For children under five, a modified version of the GCS called the Pediatric Glasgow Coma Scale (PGCS) is used, as children may not respond in the same way as adults.

Nursing Responsibilities:

1. Assessment:
   • Perform the GCS assessment at regular intervals based on the patient’s condition and facility protocols.
   • Note any changes in the patient’s score, as a decrease in GCS may indicate deterioration in neurological status.
   • Document each component of the GCS score separately (e.g., E3, V4, M5).
2. Interventions:
   • If the patient’s GCS score drops, report immediately to the physician for further evaluation and possible intervention.
   • Maintain airway patency, as patients with low GCS scores (≤8) are at risk of losing airway protective reflexes.
   • Protect the patient from further injury, especially if they are disoriented or unable to follow commands.
3. Patient and Family Education:
   • Explain the significance of the GCS score and its use in monitoring neurological function to the patient’s family.
   • Provide support and clear communication about changes in the patient’s condition.

---

Application of GCS in Various Settings

• Emergency Room (ER): The GCS is often the first neurological assessment performed on trauma patients or those suspected of having a neurological injury.
• Intensive Care Unit (ICU): Nurses use the GCS to monitor patients with brain injuries, strokes, or conditions requiring sedation.
• Post-Surgical Recovery: After neurosurgical procedures, the GCS helps evaluate recovery and the need for additional interventions.
• Pediatric and Non-Verbal Patients: In non-verbal patients or young children, the modified Pediatric GCS is used to adapt responses based on developmental level.

Conclusion

The Glasgow Coma Scale is an essential tool for nurses working with patients at risk of neurological deterioration. Proper training and regular practice in GCS assessment can significantly improve patient outcomes by identifying changes in consciousness early and prompting quick intervention. Remember to approach each assessment systematically, and always document findings accurately for continuity of care.

Reference:

Teasdale, G., & Jennett, B. (1974). Assessment of coma and impaired consciousness. A practical scale. The Lancet, 304(7872), 81-84.