The GCS evaluates three aspects of a person’s responsiveness: eye-opening, verbal response, and motor response. Each aspect is scored separately, and the scores are then summed to provide an overall GCS score ranging from 3 to 15. A higher score indicates a better level of consciousness and a less severe injury.
Eye-opening response is scored from 1 to 4. A score of 4 indicates that the person opens their eyes spontaneously, without any external stimulation. A score of 3 is given if the person opens their eyes in response to a verbal command. A score of 2 is assigned if the eyes open in response to pain, and a score of 1 indicates no eye opening at all.
Verbal response is scored from 1 to 5. A score of 5 indicates that the person is oriented and can have a coherent conversation. A score of 4 is given if the person is confused but can still communicate. A score of 3 is assigned if the person speaks in inappropriate words. A score of 2 indicates that the person makes incomprehensible sounds, and a score of 1 means there is no verbal response.
Motor response is scored from 1 to 6. A score of 6 is given if the person obeys commands for movement. A score of 5 indicates that the person localizes to pain, meaning they can move their body in response to a painful stimulus. A score of 4 is assigned if the person withdraws from pain, indicating a reflexive movement away from the stimulus. A score of 3 means the person exhibits abnormal flexion (decorticate posturing) in response to pain. A score of 2 is given for abnormal extension (decerebrate posturing) in response to pain, and a score of 1 indicates no motor response.
The total GCS score helps categorize the severity of a head injury. Scores of 13 to 15 indicate a mild head injury, 9 to 12 suggest a moderate injury, and scores of 8 or below are indicative of a severe head injury. A GCS score of 8 or lower is typically considered a threshold for intubation and aggressive medical intervention.
The GCS is a valuable tool not only for initial assessment but also for monitoring changes in a patient’s condition over time. Repeated assessments can help detect improvements or deteriorations in the level of consciousness, guiding further treatment decisions. While the GCS is widely used, it is important to remember that it is one of many tools available to healthcare professionals. Other factors, such as the patient’s overall medical condition and additional diagnostic tests, are also critical in managing head injuries.
Despite its widespread use, the GCS has some limitations. It may not be as reliable in certain patient populations, such as those with pre-existing speech or motor impairments, or in intubated patients where verbal response cannot be assessed. In such cases, alternative scales or modified versions of the GCS may be used.
