Glasgow Coma Scale Notes

Glasgow Coma Scale

Introduction

The Glasgow Coma Scale (GCS) is a neurological scale used to assess the level of consciousness in patients with acute brain injury. It evaluates eye-opening, verbal response, and motor response.

Components of the Glasgow Coma Scale

The GCS consists of three main components:

  • Eye-opening (E)

  • Verbal response (V)

  • Motor response (M)

Eye-Opening (E)

This component assesses the patient's eye-opening ability based on different stimuli:

  • Spontaneous: 4

  • Response to speech: 3

  • Response to pain: 2

  • Nil (no response): 1

Verbal Response (V)

This component evaluates the patient's verbal responses:

  • Oriented: 5

  • Confused conversation: 4

  • Inappropriate words: 3

  • Incomprehensible sounds: 2

  • Nil (no response): 1

Motor Response (M)

This component examines the patient's motor responses to commands or painful stimuli:

  • Obeys commands: 6

  • Localizes to pain: 5

  • Withdraws from pain: 4

  • Abnormal flexor response (Decorticate): 3

  • Extensor response (Decerebrate): 2

  • Nil (no response): 1

Calculating the Glasgow Coma Scale (GCS) Score

The GCS score is calculated by summing the scores from each of the three components (Eye-opening, Verbal response, and Motor response). The total score ranges from 3 to 15.

GCS = E + V + M

Interpretation of GCS Scores

The GCS score indicates the severity of a brain injury:

  • Severe brain injury: GCS score of 3-8

  • Moderate head injury: GCS score of 9-12

  • Mild head injury: GCS score of 13-15

A GCS score of 3 indicates the lowest possible score and reflects severe brain injury or deep coma.

Posturing

Decorticate Posturing

  • Characterized by the hands held to the core.

  • Abnormal flexor response.

Decerebrate Posturing

  • Characterized by the arms extended.

  • Extensor response

Examples of GCS Assessment

Example 1

A patient opens their eyes spontaneously, is oriented, and obeys commands.

  • Eye-opening: Spontaneous = 4

  • Verbal response: Oriented = 5

  • Motor response: Obeys commands = 6

  • Total score: 4 + 5 + 6 = 15

The GCS score is 15.

Example 2

A patient opens their eyes to painful stimuli, uses inappropriate words, and withdraws from pain.

  • Eye-opening: To pain = 2

  • Verbal response: Inappropriate words = 3

  • Motor response: Withdraws to pain = 4

  • Total score: 2 + 3 + 4 = 9

The GCS score is 9.