Commentary on: Teasdale, G.,Jennett, B., Assessment of coma and impaired consciousness. A practical scale.. Lancet 2(7872): 81 - 84, 1974Zaman Mirzadeh, MD, PhD1, Rami O Almefty, MD1, Peter Nakaji, MD11Department of Neurosurgery, Barrow Neurological Institute Keywords: grading system, traumatic brain injury, critical care, Glasgow Coma Score (GCS), coma
The authors wanted to generate a scale that could be used repeatedly throughout illness by a range of staff and reliably recorded and understood to assess level of consciousness.
Developed and described the GCS scale, rating 3 variables in order to determine level of consciousness:
eye opening: E4=spontaneous, E3=to speech, E2=to pain, E1=none; verbal response: V5=orientated, V4=confused, V3=inappropriate (no sustained conversation, eg. words only), V2=incomprehensible (eg. sounds, no words), V1=none; motor response: M6=obeys commands, M5=localizes painful stimulus, M4=withdrawal from painful stimulus, M3=flexor response to painful stimulus (note: although in the current GCS scale, withdrawal and flexor responses to pain are graded differently, this paper did not distinguish them in the original scale), M2=extensor response to painful stimulus, M1=no response
Regarding how differences in motor responses of upper versus lower limbs should be reflected in the overall scale, the paper states: "Any difference between the responsiveness of one limb and another may indicate focal brain damage and for this purpose the worst (most abnormal) response should be noted. But for the purpose of assessing the degree of altered consciousness it is the best response from the best limb that is recorded."
The authors conducted a validation and inter-rater reliability test of their scale by having various doctors and nurses examine the same group of patients. Unfortunately, these results were never published, and it is only mentioned that disagreements were rare. It would be informative to know exactly in what context disagreements occurred and whether there were systematic albeit small differences in application of the scale between doctors, nurses, and other staff.The Author(s) wish to thank:Project Roles:
Z. Mirzadeh (Performed Research), R. Almefty (Performed Research), P. Nakaji (Performed Research)