Glasgow Coma Scale

The Glasgow coma scale (GCS) was developed in 1974 ¹ to describe the level of consciousness specifically in patients with head injury although it is now used widely as a shorthand for all manner of presentations and has generally been validated, although concerns about its use in certain scenarios ^2-3. 

It measures the best eye, verbal and motor responses. Each is graded from worst ( = 1=1) to best ( 4(4, 5 and 6 respecivelyrespectively) and the grades added together, such that the lowest possible score is 3 and the highest is 15.

Best eye response (E)

Graded 1-4:

1. no eye opening
2. eye opening in response to pain:
   • patient responds to pressure on the patient’s fingernail bed 
   • if this does not elicit a response (or hands are unavailable) supraorbital and sternal pressure or rub may be used
3. eye opening to speech:
   • not to be confused with the awakening of a sleeping person (such patients receive a score of 4, not 3)
4. eyes opening spontaneously

Best verbal response (V)

Graded 1-5:

1. no verbal response
2. incomprehensible sounds:
   • groaning or moaning but no words
3. inappropriate words:
   • random or exclamatory articulated speech, but no conversational exchange
4. confused:
   • responds to questions coherently but there is some disorientation 
5. oriented:
   • responds coherently and appropriately to questions such as the patient’s name and age, where they are and why, the year, month, etc.

Best motor response (M)

Graded 1-6

1. no motor response
2. extension to pain:
   • extensor posturing: abduction of arm, external rotation of shoulder, supination of forearm, extension of wrist, decerebrate response
3. abnormal flexion to pain:
   • flexor posturing: adduction of arm, internal rotation of shoulder, pronation of forearm, flexion of wrist, decorticate response
4. flexion/withdrawal to pain:
   • flexion of elbow, supination of forearm, flexion of wrist when supra-orbital pressure applied; pulls part of body away when nailbed pinched
5. localizeslocalises to pain:
   • purposeful movements towards painful stimuli
6. obeys motor commands