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ADULl ~/ELDERLY C ARE N UR SING
Usi• e^ Glasgow^ Coma^ Sca^ le:
analysis and limitations
Abstract
Thls artlcle addresses the gap between the llterature and practlce In relatlon to the use of the G/asgow Coma Sea/e (GCS). lt w/11 explore leve/ of consclousness and the GCS. The instlgatlon of both central and perlpheral palnful stimu/1 Is analyzed in an effort to prevent rltual/stlc practlce. Attention is a/so glven to the lmportance of /ncludlng vital slgns when us/ng the GCS, as these can tell a lot, if not more, about the patlent's neurologlcal condltlon. Flnally, the 1/mltatlons of the GCS are examlned to asslst In a more accurate and consistent assessm ent too/ for neurologically lmpa/red patlents.
Sha roo L Edwa rds is Sen ior Lectu rcr, Univcrsity o f Hertfordsh irc, Ha tficld C ampu s, Hatfield, H c nfords hire
Accepted for publication:
Deamber 2 000
N
urses on the wards and in acc id ent
and emergency (A&E) departments
are freq uen tl y co nfron ted with
patients who have illnesses/diseases or damage
to the brain. In such situations vigorous neuro-
log1cal observanon and assessment are required
to determine the initial neurological status and
hence any dete ri oration in the patients' condi-
tion. lt is important th at when neurological
deterioration begins, nurses are ab le to identify
the symptoms. This is often undertaken by
using the Glasgow Coma Scale (GCS) (Tea sdale
and Jenne n, 1974 ).
The GCS is often proposed to be in accurate
because nursing staff use a variety of painful
Table 1. The significance of neurological assessment
Slgnlflcance
Determine a baseline for the
patient
Establish the impact of the
neurological condition
Determine any changes in the
pat1ent's neurological conditlon
Detect llfe-threatening
situations
Source: H1ckey (1997)
lnterpretatlon
Determine neurologlcal function
Determine whether the patient has
a neurological problem
Determine if the patient's
independence has been affected
Determine if the patient's daily life
has been affected
Contlnue to monitor neurological
condition over a period of time
Monitor any changes that occur
Help to detect those which could
be life-threatening
lnstigate prompt and effective
interventlons
Sharon L Edwards
st im uli, the reaction to lig ht m ethods on the
same patient, and inter pret the results differ-
ently. T h is a rt icle suggests th at nurses need to
implement a uniform way of ca rrying out th e
GCS, in their indivi du al clinical arcas, to pr o-
duce a n accurate assessment of th e patient's
neurologica l sta tu s. Th is m ay be achieved
through co ntinuing education or by develop-
ing a standard or protocol.
NEUROLOGICAL ASSESSMENT
Neuro logical assessm ent is a set of standard
observations which relate to the eval uation
of the integrity of a n individual's n ervo us sys-
te m (R ow ley a nd Fielding, 199 1). T he set of
obse r vatio ns t hat m ake up neu ro logical
assessment are aimed at individuals with
n euro log ical prob lems or illnesses and/or
pat ients who are at risk of developing com-
p l icat io ns or wo r sening conditio ns. The
activ it ies are di r ecte d at d iag n os is and
prompt interve nt ion, to enable the patient to
ret urn to m ax imal level of hea lth as early as
po s sib le (Edleman and Mandle, 1990).
Hickey (1997) indicated the professional sig-
nificance for nurses of using neu ro logical
assessment (Table 1 ).
lncluded in n euro logical assessment are the
speci fi c neurological observations. The main
reason for performing neuro logical observa-
tions is to determine if a person's neurological
condit1on is improving, remaining static or
deteriorating. Neurological observations co n-
s1st of various areas a li of which are impor-
ta nt in assessing ne urological illness/d is-
ease/deterioration.
LEVEL. OF CONSCIOUSNESS
Consciousness is a general awarcness of oneself
and the s ur ro un ding environment. lt is a
dyn am ic state and can, thercforc, be changed
(Hickey, 1997). Therc are numerous too ls used
to determine level of consciousness. The rnost
common too l used to determine level of
Bltrr! rr la ■ N t! «Y M llVKin 2001 , VOL 10. No l
USING THE GLASGOW COMA CA LE: ANALYSIS ANO LI MITATIO S
consciousness is thc GCS (Stcwart, 1996). Bdo~ the Jcvclopment of thc GCS a v:mcry of tcrms were used to describe the ~t.lte of con- sciousness, c.g. awakc, lethnrgic, obrunded, stu-
porous, comnrose (Table 2), wh1ch often meant
different things to d1fferent peoplc. The GCS is often incorporoted to give continuous monitor- ing under standard condit1ons. This leads to a determinarion of a trend in the pntient's condi- non, wh1ch can be more readily interpreted thnn by 1ust using words and a description.
THE GLASGOW COMA SCALE
The GCS was developed to assess conscious- ness with ease and to standardize clinical observations of patients with impaired con- sciousness. lt monitors the progress of head in1ured patients, patients unde r going intracranial surgery, and any other neu rolog- ical disorder (cerebra l vascu lar accident, encephahtis, meningitis). lt also minimizes variation and subjectiv1ty in the clinica l assessment of these patients. The GCS also prov1des a guide to estimare a patient's prog- nosis. Ir assesses rwo aspects of conscious-
ness: arousal and cognition (Shah, 1999):
1. Arousal mvo lves bemg aware of the
environment
2. Cognition demons crates an u nderstanding
of what che observer h as said through an ability to perform tasks. The GCS consists of three modes of behav-
iour (Table 3) :
l. The rattng for eye-opening based on a four-pomt scale ( 1-4)
- Best verbal response on a five-point sca le (1-5)
- Best motor response on a six-point scale (1-6). The seores are added toget h er to give an overall assessment of the patient's neurologi- cal status. A score of 15 represents che most responsive, while a score of 3 is the least
responsive (Nieuwenhuis, 1993). The pnma-
ry purpose of the GCS is to alert medica! and nursing staff to deterioratio n in a patient's
neuro logica l status (Lower, 1992).
Best eye-opening response
Eye-opening 1s closdy linked to bemg awake and a lert, which is easily identified. The
mechanisms for eye-opening are controlled by
a collection of neurones located in the brain
stem, hypothalamus and thalamus, which is
8ArmH joua1W. Of .Nuam«:, 2001, Vot 10, No 2
c:d lcd the reticu lar activating systc m, ,,n d ,~
stimubtcd by sensory input (Marieb, 1998).
Whcn thc set of neurones are impaired either from trauma at the time of injury or because of subsequent rises in intracranial pressure, it wi ll require a greater sensory input to produce the same response of eye-
opening (Hickey, 1997). Therefore, a bese
eye-opening response will show that arousal mechanisms located in the brain stem are
functioning (Lower, l 992).
The patient is considered to have sponta- neous eye opening wh en che eyes are opened wichout any stimulation from che nurse. If patients have their eyes closed, their state of arousal can be assessed by che degree of stim- ulation that is required to get them to open their eyes, e.g. using central painful stimu li
(Shah, 1999) (see below).
The nurse should be aware that damage to the ocu lomotor nerve (responsible for move- ment of the eyelid and eye-opening) from trauma or during intracranial surgery may
Table 2. Words used to describe level of consciousness
Level of
consciousness Description
Awake
Confused
Disoriented
Lethargic
Obtundation
Stuporous
Comatose
Alert, responds immediately and fully to commands
- may or may not be fully oriented The inability to think rapidly and clearly. There is impaired judgment and decision making This is the beginning of loss of consciousness. There is disorientation in place, impaired memory and a loss of recognition of self which is the last to deteriorate Drowsy, sleeps a lot, but is easily aroused with minimal stimuli, i.e. voice, and then responds, but may not be oriented in time , place or person Can be aroused by stimuli (not pain), i.e. shaking, and will then respond to questions or commands. Remains aroused as long as stimulation is applied, if not will fall asleep, questions are answered with minimal response. During the arousal, patient responds but may be confused This is a condition of deep sleep or unresponsiveness. The patient can only be aroused or caused to make a motor or verbal response by vigorous and repeated externa! stimulat1on (pamful). The response initiated is often withdrawal or grabbing at stimulus There 1s no motor response to the externa! environment orto any stimu li, even deep pa ín or suctioning. There is no arousal to 1n\· st "Jlus. Reflexes may be pres,~nt, abnormal movcmc nt
(postunng) to pain may be p re. 1l
93
USING THE GLASGOW COM A CAL E: ANALYSIS AND LIMITATION S
undcr!ót,rnd thc nurse's commancl bccau,c
rhcy Jo not undcrstJnd thc languagc or they
have a hcaring dcf1c1t.
lf therc 1s any damagc to rhe spccch centres
in thc hr.lin, the patient may be awake but
cannor t.1lk. In rh1s insrancc, thc pauent 1s
said to be aphas1c and seores one (Table 4). Other foctors such as dy sphasia (Table 5),
presencc oí an endotracheal or tracheotomy
tube, fracrured mandible or maxillac shou ld
be considered ar che time of assessment, oth-
erw1se the pat1ent will seem worse than he/shc
1s in reahry (Harad and Kcrstcin, 1992).
Best motor respo11se
The best motor response is used ro determine
how well che brain is functioning as a whole.
This assessment does not anempt to pinpoint
the spec1fic area of the bram that is damaged; it
shows che parient's ability to obey simple com-
mand s such as 'put out your tongue', which
will idennfy how weU che brain is integrating
with che rest of che body.
However, che request to 'squeeze my fingers'
should be avoided, as chi s is a primitive reflex
and may occur involuntarily and not in
response to a command. If used the patient
muse also be asked to release his/ her grip
(Shah, 1999). Family members can ofren be
falsely encouraged by chis reflex; therefore, it
1s much safer to ask che pauent to 'hold up
rwo fingers', 'hold up your right hand' or
'touch your right ear' (Lowcr, 1992).
The addition of motor power or srrength
of the limbs provides information of motor
movement. Ir can give vital information of a
developing hem1paresis on one side of the
body. Recording strength and power of
limbs is assessed through the patient's abili-
ry to overcome res1stance, e.g. get che patient
to pull you towards him/her and push you
away (Table 6).
Another area for consideration when
assessing best motor response is the presence
of a drifr in the patienr's upper limbs. To
asscss if a drift is present:
- Place thc patient in an upnght position
- Ask thc paticnt ro close his/her eyes
- Extend his/her arms, palms up
- Observe for arm movement. lf the patient's arms remain parallel this indi-
cares no drift, bur 1f rhere is a downward drift
of the arms or pronation of the palms on one
1idc a mild hmúparcsis may be suggested.
Anothcr arca for consideration when undertak-
8Am5H JOUKHAL OF NIJUIHG, 2001, VOL 10, No 2
,~ '"'-.. ...... Table 4. Types of aphasia ·- (^) .... _.,..,,.,.,.-
Type of aphaala Descrlptlon
Receptive aphasia lnability or difficulty in receiving written or spoken
language Expresslve aphasia lnability or difficulty in expressing self using written orspoken language Global aphasia lnability to receive language or express self using written or spoken language
Table S. Types of dysphasia
Type of dysphasla Descrlptlon Receptive dysphasia lnability or difficulty in understanding the spoken word, which is dueto damage to the Wernicke's speech centre that is responsible for comprehension of speech Expressive dysphasia lnability ar difficulty in putting thoughts into words, dueto damage of the Broca's speech centre. In this case patients can understand what has been said to them, but cannot reply with the right words Dysarthria Slurred speech
ing best moto r response is that of posturing,
previous ly known as decortica re, and decere-
brate moveme nt (Shah, 1999 ). These motor
responses are now known as abnormal or spas-
tic flexion and abnormal extension (Figure 1 ).
Pai11f11I stimuli: If rhe patient wi ll not open
his/her eyes or obey commands, the nurse
mu st inflict a painful stimulus and view che
response. Ther e are many variations in the
type of stimuli to use and when to use it to
achieve a response from che patient. There is
confusion in the literature about the painful
stimulus used to elicit a response from a
patient. Painful stimuli generally fall into rwo
categories: central and peripheral. The brain
responds to central stimulation; che spine
res ponds to peripheral s umulation.
Central painful stimulation: Shah ( 1999)
indicares three ways central painful stimulus
can be applied: trapezium squeeze, sup raor-
bital pressure and sternal rub (Table 7).
It is often proposed that ch e srernal rub 1 s
the most effective mean s of central s1mulat1on
(Proehl, 1992). However, the sternal rub
should be discouraged as in m any instances 1t
leaves unsightly bruising upon che pat1 ent\
chest (Allan and Calne -Seymour, I 98Q;
Frawley, 1990; Stewart, 19% ). 1 here 1s onh
95
AnU LT/ELD tRLY CARE N uRS ING
,inl'cJot,11 t·vidl' ll Cl' to ,upport thl' dJim that
rhl' , tan .ti rub ". 111 y more ltkdy to c.1usc
bru"111g, or .rny othcr J ,1111.1gc ro thc patil'nt,
rh.111 rhc v.1r1 o u, rypc!> of painful sttmult, c.g.
t h t• tr.1p1Niu111 !,quee7l: ( Lowr y, 1998).
Thc prohlem w1th thc ce ntral sttmuli idcntt-
ficd t!> rh.1t oftcn rhey ,ire carried out b)' dif-
fcrcnt nur!>1ng staff, us 111g v:irious methods of pJinful snmuli to asscss thc s:une patie nt's neurolog1cal s tatu s. The type of st1mulus
Table 6. Determining limb strength
Grade Descrlptlon
Grade 5 Normal strength
Grade 4 Mild weakness
Grade 3 Able to lift extremity against gravity, but not against resistance
Grade 2 Able to move extremity, but not against gravity
Grade 1 Flicker of movement Grade O No movement
Abnormalor spast,c flex,on Adduct1on of arms coupled w1th extens1ons of legs and plantar flexion of fee t : md1cates severe cerebral damage a nd mt errupt ion of nerve pathways from the brain's cortex to the spine
Abnormal extens,on Ad d uct,on and inte rna! rotat,on of uppe r and lowe r extem1t1es, feet plan ta r fl ex a nd may or may not be acco mpa me d by o p,sthotono s ( pronounced, abnormal arch,n g of th e ba ck), loss of the ab1lity to se nd mfo rma t1 o n to a nd from th e c ere brum. owing to d am a ge to the bra m s te m
R~ure J.. Abnannal ffexlon and abnonnal exten1/an.
varics depending on how the nune was
traincd, and how comfortable he/she feels in
u,ing spccific rypcs of stimuli. Often the 1ter-
nal rub 1s implemcntcd as it is often felt to be che easicsc ro pcrform. le is proposcd that the
sternal rub is an outdated practice. The best
merhod of gcnerating central painful stimuli is to use the trapeztum squecze (Lower, 1992). Thc duration of the stimulus is very impor-
tant (Lower, 1992). A patienc who seems
deeply uncon sc ious may posture very quickly in response to a 5-second trapezium squeeze, but if painful stimuli are concinued for a fur- ther 20-30 seconds, it may be discovered that po st uring is just th e initial reaction; after that, the brain may respond more fully to a higher leve( of s timulus, to show th e patient's true baseline. If the patient doe s not respond after 30 seconds the painful s timuli should stop.
Periph era l painfu/ stimulí: Frawley ( 1990)
suggested that for assessing eye-opening a peripheral painful stimuli should be used
rather that a central one. Thi s is because the
la tter will often cause eye closure by inducing a grimacing effect. Peripheral pain 1s applied directly to an unmoving arm or leg. lt differs from central pain in that che spme will respond as a pure reflex and the patient will pull che stimul:ited part away. The application of peripheral pain to various sites can test flexion and localize pain (Watson, 199 7):
- Press ure to the nail bed of the patient's toe or finger
- Press ure directly to the nail bed but at the side of the fingers. Woodward (1997a) recommended apply- ing pressure to the nail bed of a patient's toe or finger. Shah ( 1999), however, refers to this as a horrifymg pracrice, JS just under the nail
bed there are extensor tendons, aponeuroses,
microcirculation and nerves, which may be
damaged by insensitive handling, especiaUy
when the use of an instrument, e.g. a pen or
syringe barre(, is involved. Pricking the
patient's finger is an undesirable practice
because it can cause damage to the patient (Allan and Calne-Seymour, 1989). Lower ( 1992) suggested that pressurc should not be applied directly on to the nail bed but at the side of the finger. By carrying it out this way no damage is causcd to the structura under the nail bed. The first or second fingcr or toe should only be used as they are more sensitive to srimuli (Davidhizar and Bartlett
1997). Woodward ( 1997a) doa noc ....,.
AI)Ul J/ELDE RLY CARE NURSING
'
l ~"-' b,t ,1.·ction lll th1.· l~l..l!'igO\ oma Scak (G C~) is thc obi;,;1.•rTa1 ion of vital ,igm. Although ... it i~ not strictly part of thc GC~, 1t is important and can providc esscntial additional information ... Altcrations in a patient's ncurological condition can result in a changc in vital signs.
QA
w11h h1,/hl·r puptl, which .irc normnl for
h11n/ hi:r, c.~. prcv 1ot1!, l"YC in¡ury, car.,r:tct,,
bltnclm·" 1n onc cyc. lt i, imporrnnt to note:
- fhc puptl \1 7C ( hgurc 2): .1vcr:1ge pupil ,i1c ,., 2- 5 mm
- Thc pupil rcacrion ro light: bnsk, s lugg1sh
or fi,ed
- Thc !. hapc of thc puptl should be round
- lf both pupils rcact equal to light and are
equal 111 s1ze.
Prog re ss ive dilatation and loss of puptl
reaction on one side occurs as a result of pres-
sure on thc th1rd c ra111al nerve, on that si de,
indicating an enl,trged inrracranial mass
(haematoma) (S pecht, 19 95). When raised
intracranial pressure is not corrected, cerebral
oedema eventually leads to compress 1on of
the rh1rd cranial nerve on rh e orher side, so
ne1th er pupil thcn reacrs to light. Under thesc
c 1rcumstances bra111 damagc is ltkely ro be
severe (Watson, 1997). In addition, so rne
drugs, e.g. atrop111e, dilate the pupil, and opi-
ates, e.g. morphine, const ri ct the pupil.
There are different opinions on how to
carry out pupillary response. The profession-
al s h111 es the li ght 1nro rhe pa tt e nr 's eyes to see
1f they constnc t (H arrah tll, 1996; Shah,
1999). However, Lowry (1998) suggests that
111 stead of shining rhe li ght directly 111t o rh e
patienr's eyes, a to rch sho uld be shonc over
the puptl and beyond 1t. Thc rationale for th1 s
1 s that 1f one sh111es a li ght directly into the
eye, by the rime the pupil is obse rv ed ir would
have already re sponded.
lt is best to carry th1 s out in dim light111g as
o ne sees the eyes consm cr better when light 1 s
shone on them (Woodward, 1997b; Shah,
1999). Davidhizar and Bartlett ( 199 7) d is-
agree by say 111g that ir should be carried out
111 na rural li ght. The rype of ltghting should be
agreed between staff to eliminare any incon-
s1stenc 1es 111 the panent's score (Proehl, 1992).
A discrepancy of not dimming the light cou ld
occur during the night whereby 111accuracy of
puptl, s 1ze and reacrion may appear narurall y.
Pupil sizes in mm
F1gure 2. Pup/1 slze observed durlng Glssgow Coma Scsle.
Observation of vital signs
The la,r ,cction of che GCS is the observation
of vit:tl s1gni.. Alchough Shah ( 1999) suggests
thar 1t i!. not stm:tly part of the GCS, it is
imporrant and can providc essential addition-
al informar1on (Sccwart, l 996; Lowry, 1998).
Alrcrations in a patient's neurological condi-
(I0n can resulr 111 a change 111 vital s1gns. lf a
patient has a h1gh remperature, because of
damage to che hypothalamus, chis 111creases
cerebral metabolic oxygen requ1rement,
which is an unwanted complicarion when
oxygenat1on of the brain may already be
depleted (Shah, 1999).
Lowry (1998) srressed che importance of
taking blood pressure in the monitoring of
neurological observations. Control centres
for blood pressure, heart rate and respirarion
are a li located in rhe brain scem. Damage to
rhis arca of the brain can affecc rheir control
(Harrahill, 1996).
In seve re brain trauma, whereby rhere is
widespread cerebral oedema and a high
111tracranial pressure (ICP ), hypox1a,
ischaemia and acidosis occur. To prevent a
reducrion and mainca111 a constant blood Aow
when ICP rises a slow and somerimes dra-
matic ri se in blood pressure (g reacer than
140/95 mmHg) occurs, chrough homeostatic
control mechanisms. lt is not until ali che
compensatory mechanisms (e.g. displacement
of cerebral spinal fluid, vasoconstriction) that
maintain cerebral perfusion have been
exhausted that a significant nse in ICP is
observed (McCance and Huether, 1997).
Carbon d1oxide begins ro accumulate in the
brain (hypercapnia) owing to hypoxia.
Hypercapnia causes vasod1larion ar the local tis-
s ue level leading to a drop in hydrostatic prcs-
sure 111 che vessels and blood volume increases,
causing a funher ri se 111 ICP. An 111crease in car-
bon dioxide in the blood snmulatcs chemorc-
ceptors. Th1s brings about changes in mpirato-
ry rare and depth of breathing in an attempc to
excrete rhe excess carbon dioxide.
Other changes occur in heart rate and
breathing rate pattern owing to hypoxia of
the hrain srem. Cerebral hypoxia leads to
deteriorat1on of the respiration centres in the
brain stem and clinical signs of bradycardia,
Cheyne-Stokes respiration and/or central neu-
rogenic hypervenrilation (McCance and
Hucrher, 1997).
The vital signs are often an arca that staff eliminare during neurological aueument.
]OOJ Yni tQ.
USING THE GLASGOW COMA S E:^ ANALYSIS^ AND^ LI^ MITATIONS
Presunuhly ,r.1ff fcel th,tt the .tctual neuro - log , c.11 oh,crv,ltlom .tre more ,mportant.
Walsh and Ford ( 1993) .1scerta111 ch.ir nurses
Jo not undcrstand the importance of carrying out v1t.1l s,gn!> on thc, r own, let alone in con- 1unctton w 1th neurolog1cal assessment. They .1lso say that if nurses do not understand the purpose of carrying out vital signs in relation to neurolog,cal observations then ritualistic pract,ce ,s likely to occur.
FREQUENCY OF NEUROLOGICAL OBSERVATIONS
The GCS provides a quick guide for evalua- t1on of the acutely ill patient (Hudak and
Gallo, 1994 ). However, to detecr changes in
conscious level in rhe clinical situation it m ay be necessary to record neuro logical observa- tlons ar frequent intervals. There 1s contra- dicting ev, dence as to when to car ry out the GCS on a patient: as often as every
5-JO minute s in che acure un stab le patient or
as 111frequently as every 4 ho u rs in rhe appar-
ently srable parient (Srewarr, 1996 ). The use
of 4-hourly neuro logical observa r ions is quesrionab le as ro wherher any sudden dete- noratton 111 a par,enr wi ll be detected
(Hickey, 1997).
Fraw ley (1990) suggests that the GCS
s hould be carried out every 10-15 minute s,
bur does nor g1ve a rarionale. Boylan and
Brown ( 1985) state th at ir shou ld be carried
out every 15 minutes for the fir st hour, every
half an hour and then every hour, again no
rationale is g1ven. Ir appears that 1 hour
should be rhe maximum time a ll owed between neuro logical observation s so rhat any signs of deterioration can be observed. Neurolog1cal observations are generally carried out in accor dance wit h che patient's condition. As rhe parient's con d ition improves the gap 111 between times for the 1 mplemenratton of the GCS becomes longer unril he/she does not require rh em any more. This seems to be a mo re rea li stic way to judge the timescale when the too! should be carried out. Thus, the frequency of GCS recordings sho u ld be determined by pract it ioners' pro- fessional judgment.
THE UMITATIONI OF' THE GCS
The limiurions necd to be ana lyzed so these may be raught to staff and overcome, 111 orde r
Bun1H JOUIINAL o, NUIISING. 2001, Vol 10, No 2
th at rhe GCS is implementcd rnr rectl y. l'h1 ·rc are many variat1ons in the 1mplcmentat1on ot thc GCS, as nursing and mcd1ca l staff rely heavily on its rcsu lts.
Acc 11 racy of tl,e t oo /
Boylan and Brown ( 1985) ascertained tha t of
a li t he observaciona l pa r amcters which nu rs- es kee p, neurological obse rvations are rhe most accurate ly maintained. lt is suggested thar this is because rhey are the least fre- quen tl y req u ired set of observarions ourside a specialist unir. Neuro logical observarion is also more accurarely interpreted than any other observation. The accuracy of the roo! is crirical ro
obrain valid data (Har rah,11, 1996). The
GCS h as been demonstrated and proved ro be a useful, rel iable and pract i ca! too!
(Juarez and Lyons, 1995 ).
How ever, Rowley and Fielding ( 199 1) con-
ducted a study to determine wherher the GCS was accurate when used by inexperienced a nd experienced staff. The findings were thar rhe GCS was used accurarely by experienced and highly trained users, bue inexperienced users mad e consistent errors. The srudy s howed thar the error rare was hig hesr ar che interme- diare level of consciousness for which ch e detection of change is viral. The majoriry of rimes on rhe ward ir was che student nurses who implemenred ch e GCS
(Rowley and Fielding, 1991 ). Man y pattents
often require neuro logical observations, but the qua lified staff simply do not always have
the time. If chis is the case, and the s rudenr
nurse is inexperienced in undertaking neuro- logical observations, then t he results obtained from the GCS could be inaccurate. However,
the sa mple in Rowley and Fielding's (1991 )
st udy was relatively sma ll and, as such, gen- era lizarions can n ot be made. Alrhough rhe literature suggests that sru- dents are not expenenced enough ro ca rry out the GCS, it is felt that they sh ould be allowed to be involved in neuro logical a,scss- ment. Ir is recommended rhat srud ent nurses sh ou ld undertake neurolo gical observacions after a qua lified member of sraff ha s first ensured tha t the s rud e nt is cap.1ble of 1mple- mennng t he rool. Qualified staff s houl d superv ise the srudent, whilc implementmg t he tool for the first da y or lon ge r if neccs sary. T h,s will ensure that rhc rno l 1\ n seJ correctly and cons,~tenth
Alth ,1 ugh thc iu c raturc suggcsts that studcnt s are n ot cxperienccd enough to carry out the Glasgow Coma Scale (GCS), it is felt that they should be allowed to be involved in neurological assessment. It is recommended that student nurses should undertake neurological observations after a qualified member of staff has first en sured that the student is capable
of implementing ' the tool.
99
p,ttient the same w.1y cvery rime. lf ncur o-
logic.:al obscrv.ltlons .1rc to make seni,c then
the same nurse should makc the o bscrva-
tions on a p.1t1ent for thc dur.ui o n of hi s/ her
shift. lt is only in this way that obl,erved
changcs are more likcly to be real changes,
and no t apparent ones caused by different
perso nnel nukmg the observ:1tions (Walsh
and Ford, 1993). Frawley (1 99 0) suggested
that th c GCS will never realize its full poten-
tial until each nur se defines the terms o n the
c hart. and refine s hi s/ he r t ec hnique of
assessing the patient.
The acrions taken by th e nurse must be on
a continuum with th ose who have preceded
ham/her and those wh o will follow. Thi s cou ld
be achieved at nurse-nurse handov er when
the GCS pr ocess could be discussed toge ther
to ascertain how it was performed and the
paanful sttmuli used. This would assist in
maantaining accuracy throughout a patient's
care. To improve this aspect of care, a proto•
col o r s tandard could be devised to mamtain
consastency when implementing the GCS.
Knowledge and skills
Watson et al ( 1992) suggested th at ali nursing
staff are trained to use the GCS. How ever,
those who are capable of using the GCS effec·
tively are in the mino rity (Lowry, 1998). lt is
of paramount importance th at nur ses ha ve
the knowledge and skills competently to ca rry
out neurologacal assessment usi ng th e GCS
( lngram, 1994 ). Contmuing e ducati o n is
required to keep s taff up to date and to main-
tain consistency between tho se s taff wh o use
the GCS regularly, infrequently or not at a li.
CONCLUSION
The GCS is an instrument for assessing lev e!
of consciousness. lt inco rporares eye-opening,
verbal response, movement of limbs, the
pupillary response, viral signs and it provides
an adequate inirial assessment of patients. lt
is an important tool; however, debate s con-
rinue about its use and methods. lt is a wide-
ly uscd tool for recording neurological obser-
vations, but as this anide has shown the tool
has a series of inherenr limitations.
There is scope for improving the accuracy,
interpretation, validity and reliability, consis-
tency and the knowledge and skills in rclation
to me GCS to increue awarencss among sraff
of the implications of the results obtained. lt
11u1wt jolaNAL OI NlalDlc;, 2001, VoL 10, No 2
as cs~cntial for nurses to hove thc kno wll'dgc·
and skill to be a ble to carry out the GCS co m-
petently in order to provide a foundation for
the dcvelopmcnt of improving n eu rologacal
assessment in the furure. 1111
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Hi ckey JV (1 997) The Clinical Practrce of
Neurological Nursing. 4ch edn. JB Lippin co t r, New York Hudak CM, Gallo BM ( 1994) Critteal Care Nursmg: A Ho list,c Approach. Lippincon. Philadelphia lngra m N (1 99 4 ) Kaowledgc and lcvcl of con• scio usness: app licarion to nursing pr:icrice. J Adi• N11rs 20 (5 ): 88 1- Jennett B, Teasdale C (1 98 l) Managcme nt of Bram lniury. Davis, Philadelphia Jua rez J, Lyons M (1995) lnterrater reli ab ility of the Glasgow Coma Scalc. J Neurosci Nurs 27 (5): 283- Limon AD, Mattcrson MA, Naebius NK, eds ( 19 95) lntrod,ictory Nursmg Care of Adult s. WB Saunders, Ph ilade lphia Lower J ( 1992) R:ipid ncuro assessment. Am J N,m 92 (6): 38- Lowry M ( 1998) Emergency nursing and the Glasgow Coma Scale. Accid Emerg N 11rs 6(30): 143- McCance KL, Hu et h er SE ( 1997) Pathophys,ology: The 81 0/og,c Bas,s {or D,seasc III Adults and Childrc n. 3rd cdn. Mosby, Sr Lou 1 s Marieb E ( 19 98) Hum an A11atomy a11d Physiology. 4th cdn. Addison -Wesley, Mento Park, Ca li fornia Nieuwen hu is R ( 1993) Teamwork m Neurology. Chapman a nd Ha ll , London Proe hl J A (1992) The Glasgow Co ma Scalc: do it a nd do it righr. J Emerg Nurs 18 (5): 421- Rowley G, Fielding K ( 1991) Reliabihty and accura- cy of rhe Glasgow Coma Scale w1th ex pcn enccd and inexpe ri enccd users. J,ancct 337: 535- S hah S ( 1 999) Neurolog1cal assessmcnt. Nurs Sta nd 13 (22): 49- Specht S ( 1995) Cerebral oedem a: bn ng rhc bram back d own to sizc. Nursmg 25( 1 1 ): 34- Stewart N ( 19 96) Ncurological obscrvanons. Pro{ N urse 11 (6): 377- Teasdalc G, Jennctt B () 974) Assessmenr of coma and impaired co nsciousncss. Lanc:et 2: 81 - Walsh M, Ford P ( 1993) Nursing R1t11als. Rcscarch ami Rationale Actlons. Buttcrworth-Hemcm.1nn, Oxford Watson M (1997) C /111 ,ca/ Nursm¡: ,md Rrlated Scie11cc. 5t h e dn. Bai l11 crc Tinda ll , London Watson M, H orn S, C url J ( 1 992 ) Scarchmg for s1gns of reviva l. Pro{ Nmst' 7( l O): 6 7 0- Woodward S ( 1997a) Pract1 cJ I procedures for nur\ - es - ncurological observ:mnn s 3: l11nb rc~pon~- es. Nurs Tunes 93(Suppl 47): l - Woodward S ( 19976) PrJct1cal procedures ior nur se~ - neurolog1cal oh~cn·.11,om 2 : p11p1I response. Nurs Times 91 (',uppl 46): 1 -
KEY PO IN TS
■ When nurses are confronted with a patient who requires neurological observations, the Glasgow Coma Scale is used.
■ The literature is conflicting in relation to how the GCS should be undertaken in practice.
■ Accuracy of the GCS tool is questioned. Consistency is not achieved as nursing staff often use different painful stimuli and reaction to light methods on the same patient. and interpretation of the results obtained vary. ■ lmpro ve d knowledge and skills are required to enable nurses to become competent to carry out the GCS.
■ In ind1v1dual cli na cal areas, a un1form way of carryang out the GCS Is requ1red, an arder to produce an accurate assessment to determine ;;i pat 1ent"s neurolog1 cc3I status
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