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glasgow_coma_scale

Glasgow Coma Scale (GCS)

see also Paediatric Glasgow Coma Scale.

Glasgow Coma Scale use became more widespread in 1980 when the first edition of the Advanced Trauma and Life Support recommended its use in all trauma patients. Additionally, the World Federation of Neurosurgical Societies (WFNS) used it in its scale for grading patients with subarachnoid hemorrhage in 1988. The Glasgow Coma Scale has since been incorporated in numerous clinical guidelines and scoring systems for victims of trauma or critical illness. This includes patients of all ages, including the preverbal children. Additionally, the Glasgow Coma Scale is used in more than 75 countries 1).

The scale was published in 1974 by Graham Teasdale and Bryan J. Jennett, professors of neurosurgery at the University of Glasgow's Institute of Neurological Sciences at the city's Southern General Hospital 2).

GCS is used as part of several ICU scoring systems, including APACHE II, SAPS II, and SOFA, to assess the status of the central nervous system. A similar scale, the Rancho Los Amigos Scale is used to assess the recovery of traumatic brain injury patients.

Assessment of a patient’s clinical condition, and how it may change, is a cornerstone of care for people with head injury and for those with other kinds of acute brain damage. The Glasgow Coma Scale (GCS) is widely used for this purpose, reflecting its utility in observing a patient’s responsiveness, or so-called “consciousness level,” and communicating this finding clearly and consistently 3) 4) 5).

The Glasgow Coma Scale is used to assess 3 aspects of a patient’s responsiveness (eye, verbal, and motor responses). Each of these aspects contains information about prognosis 6) 7).

Soon after the Glasgow Coma Scale was described, the findings of the 3 components were combined in a summary total score, derived from the simple addition of a notation assigned to each of its components 8).

The GCS score is widely used as an index of “overall” brain damage, which is the most important feature in distinguishing head injuries of differing severities and in monitoring patient progress and estimating prognosis 9) 10).

In accord with this, focal indices, such as brainstem features, were not incorporated into the scale and were intended to be assessed separately 11).

Nevertheless, some clinicians have held the view that more complex scores, which would include extra physiological features, would nevertheless be useful 12) 13) 14).

The GCS score, together with information about pupil reaction, conveys to the physician most of the clinical predictive information in head-injured patients 15) 16) 17).

Reliability of the GCS is influenced by multiple factors and as such is context dependent 18).

Eye response (E)

There are four grades starting with the most severe:

No eye opening

Eye opening in response to pain stimulus. (a peripheral pain stimulus, such as squeezing the lunula area of the patient's fingernail is more effective than a central stimulus such as a trapezius squeeze, due to a grimacing effect).

Eye opening to speech. (Not to be confused with the awakening of a sleeping person; such patients receive a score of 4, not 3.)

Eyes opening spontaneously

Verbal response (V)

There are five grades starting with the most severe:

No verbal response

Incomprehensible sounds. (Moaning but no words.)

Inappropriate words. (Random or exclamatory articulated speech, but no conversational exchange. Speaks words but no sentences.)

Confused. (The patient responds to questions coherently but there is some disorientation and confusion.)

Oriented. (Patient responds coherently and appropriately to questions such as the patient’s name and age, where they are and why, the year, month, etc.)

Motor response (M)

There are six grades:

No motor response

Decerebrate posturing accentuated by pain (extensor response: adduction of arm, internal rotation of shoulder, pronation of forearm and extension at elbow, flexion of wrist and fingers, leg extension, plantarflexion of foot)

Decorticate posturing accentuated by pain (flexor response: internal rotation of shoulder, flexion of forearm and wrist with clenched fist, leg extension, plantarflexion of foot)

Withdrawal from pain (Absence of abnormal posturing; unable to lift hand past chin with supra-orbital pain but does pull away when nailbed is pinched)

Localizes to pain (Purposeful movements towards painful stimuli; e.g., brings hand up beyond chin when supra-orbital pressure applied.)

Obeys commands (The patient does simple things as asked.)

GMS score alone and GCS do not differ in identifying children with serious TBI. Eliminating the eye and verbal components of GCS does not adversely affect the accuracy of this tool to identify children at risk for serious TBI 19).

Because the motor component of the GCS contains virtually all the information of the GCS itself, can be measured in intubated patients, and is much better behaved statistically than the GCS, Healey et al. believe that the motor component of the GCS should replace the GCS in outcome prediction models. Because the m component is nonlinear in the log odds of survival, however, it should be mathematically transformed before its inclusion in broader outcome prediction models 20).

Limitations

Although GCS is of great descriptive value and is one of the strongest predictors of outcome in TBI, early structural pathological abnormalities detected by computerized tomography (CT) may be of similar predictive value 21) 22) 23).

Furthermore, GCS is subject to error resulting from, for instance, alcohol intoxication, sedation and intubation, and inter-rater variability 24) 25).

Strategies for reporting the GCS varied greatly and 35% of participants limited the reporting to a summary score. Moreover, different approaches were used when one of the components could not be assessed. Overall, the surveys have identified a general lack of standardization in assessment and reporting of the GCS. The results illustrate the need for continued education to improve reliability of assessments through guidance to a standard approach 26).

1)
Jain S, Iverson LM. Glasgow Coma Scale. 2018 Jun 6. StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2018 Jan-. Available from http://www.ncbi.nlm.nih.gov/books/NBK513298/ PubMed PMID: 30020670.
2)
Teasdale G, Jennett B. (1974). “Assessment of coma and impaired consciousness. A practical scale.”. Lancet 13 (2): 81–4. PMID 4136544.
3)
Reith FCM, Van den Brande R, Synnot A, Gruen R, Maas AIR: The reliability of the Glasgow Coma Scale: a systematic review. Intensive Care Med 42:3–15, 2016
4) , 10)
Teasdale G, Maas A, Lecky F, Manley G, Stocchetti N, Murray G: The Glasgow Coma Scale at 40 years: standing the test of time. Lancet Neurol 13:844–854, 2014
5)
Teasdale G, Jennett B: Assessment of coma and impaired consciousness. A practical scale. Lancet 2:81–84, 1974
6)
Reith FCM, Lingsma HF, Gabbe BJ, Lecky FE, Roberts I, Maas AIR: Differential effects of the Glasgow Coma Scale Score and its Components: an analysis of 54,069 patients with traumatic brain injury. Injury 48:1932–1943, 2017
7)
Teasdale G, Murray G, Parker L, Jennett B: Adding up the Glasgow Coma Score. Acta Neurochir Suppl (Wien) 28:13– 16, 1979
8)
Teasdale G, Jennett B, Murray L, Murray G: Glasgow coma scale: to sum or not to sum? Lancet 2(8351):678, 1983
9)
Brain Trauma Foundation, American Association of Neurological Surgeons: Management and Prognosis of Severe Traumatic Brain Injury. Campbell, CA: Brain Trauma Foundation, 2000
11)
Jennett B, Teasdale G, Braakman R, Minderhoud J, KnillJones R: Predicting outcome in individual patients after severe head injury. Lancet 1(7968):1031–1034, 1976
12)
Benzer A, Mitterschiffthaler G, Marosi M, Luef G, Pühringer F, De La Renotiere K, et al: Prediction of non-survival after trauma: Innsbruck Coma Scale. Lancet 338:977–978, 1991
13)
Born JD: The Glasgow-Liège Scale. Prognostic value and evolution of motor response and brain stem reflexes after severe head injury. Acta Neurochir (Wien) 91:1–11, 1988
14)
Wijdicks EFM, Bamlet WR, Maramattom BV, Manno EM, McClelland RL: Validation of a new coma scale: The FOUR score. Ann Neurol 58:585–593, 2005
15)
Braakman R, Gelpke GJ, Habbema JD, Maas AI, Minderhoud JM: Systematic selection of prognostic features in patients with severe head injury. Neurosurgery 6:362–370, 1980
16)
Marmarou A, Lu J, Butcher I, McHugh GS, Mushkudiani NA, Murray GD, et al: IMPACT database of traumatic brain injury: design and description. J Neurotrauma 24:239–250,2007
17)
Steyerberg EW, Mushkudiani N, Perel P, Butcher I, Lu J, McHugh GS, et al: Predicting outcome after traumatic brain injury: development and international validation of prognostic scores based on admission characteristics. PLoS Med 5:e165, 2008
18)
Reith FC, Synnot A, van den Brande R, Gruen RL, Maas AI. Factors Influencing the Reliability of the Glasgow Coma Scale: A Systematic Review. Neurosurgery. 2017 Jun 1;80(6):829-839. doi: 10.1093/neuros/nyw178. PubMed PMID: 28327922.
19)
Acker SN, Ross JT, Partrick DA, Nadlonek NA, Bronsert M, Bensard DD. Glasgow motor scale alone is equivalent to Glasgow Coma Scale at identifying children at risk for serious traumatic brain injury. J Trauma Acute Care Surg. 2014 Aug;77(2):304-9. doi: 10.1097/TA.0000000000000300. PubMed PMID: 25058258.
20)
Healey C, Osler TM, Rogers FB, Healey MA, Glance LG, Kilgo PD, Shackford SR, Meredith JW. Improving the Glasgow Coma Scale score: motor score alone is a better predictor. J Trauma. 2003 Apr;54(4):671-8; discussion 678-80. PubMed PMID: 12707528.
21)
Marmarou A, Lu J, Butcher I, et al. Prognostic value of the Glasgow Coma Scale and pupil reactivity in traumatic brain injury assessed pre-hospital and on enrollment: an IMPACT analysis. J Neurotrauma. 2007;24(2):270-280.
22)
Maas AI, Steyerberg EW, Butcher I, et al. Prognostic value of computerized tomography scan characteristics in traumatic brain injury: results from the IMPACT study. J Neurotrauma. 2007;24(2):303-314.
23)
Raj R, Skrifvars M, Bendel S, et al. Predicting six-month mortality of patients with traumatic brain injury: usefulness of common intensive care severity scores. Crit Care. 2014;18(2):R60.
24)
Shahin H, Gopinath SP, Robertson CS. Influence of alcohol on early Glasgow Coma Scale in head-injured patients. J Trauma. 2010;69(5):1176-1181; discussion 1181.
25)
Marshall LF, Marshall SB, Klauber MR, Van Berkum Clark M. A new classification of head injury based on computerized tomography. J Neurosurg. 1991;75(11):S14-S22.
26)
Reith FC, Brennan PM, Maas AI, Teasdale GM. Lack of Standardization in the Use of the Glasgow Coma Scale: Results of International Surveys. J Neurotrauma. 2016 Jan 1;33(1):89-94. doi: 10.1089/neu.2014.3843. Epub 2015 Aug 12. PubMed PMID: 25951090.
glasgow_coma_scale.txt · Last modified: 2018/08/10 12:41 by administrador