Rev. Bras. Anestesiol. vol.67 número3

(1)

REVISTA

BRASILEIRA

DE

ANESTESIOLOGIA

PublicaçãoOficialdaSociedadeBrasileiradeAnestesiologia

www.sba.com.br

SCIENTIFIC

ARTICLE

Comparison

of

effectiveness

of

intubation

by

way

of

‘‘Gum

Elastic

Bougie’’

and

‘‘Intubating

Laryngeal

Mask

Airway’’

in

endotracheal

intubation

of

patients

with

simulated

cervical

trauma

Esra

Yildiz

Sut,

Solmaz

Gunal,

Mehmet

Akif

Yazar

∗

_,

_Beyazit

_Dikmen

DepartmentofAnesthesiology,AnkaraTrainingandResearchHospital,Ankara,Turkey

Received12January2016;accepted29March2016 Availableonline30May2016

KEYWORDS Difficultairway; Cervicaltrauma

Abstract

Purpose:Inthisstudy,weevaluatedtheeffectivenessofintubationsbywayof‘‘GumElastic Bougie’’and‘‘IntubatingLaryngealMaskAirway’’inendotrachealintubationofpatientswith simulatedcervicaltrauma.

Method: 134patientswereincludedinthestudy.Allpatientswereplacedcervicalcollarfor asimulatedcervicaltrauma. Patientswere allocatedrandomlyinto threegroups: GroupNI (n=45)intubationwithMacintoshlaryngoscopy,GroupGEB(n=45)intubationwithGumElastic Bougie,andGroupILMA(n=44)intubationwithIntubatingLaryngealMaskAirway.Thenumber ofintubationattempts,successofintubation,durationofcompletevisualizationofthe lar-ynx,durationofintubation,user’sperformancescore,hemodynamicchangesandtheobserved complicationswererecorded.

Results:SuccessofintubationinthefirstattemptwashighestinGroupGEBwhileitwaslowest inGroupILMA.Regardingtheintubationsuccess,ratesofsuccessfulintubationwere95.6%, 84.4%and65.9%inGroupsGEB,NI,andILMA,respectively.Durationsofvisualizationoflarynx andintubationwereshorterinGroupsNIandGEBthaninGroupILMA.Thisdifferencewas sta-tisticallysignificant(p<0.05)whiletherewasnosignificantdifferencebetweenGroupsNIand GEB.Thenumberofpatientswith‘‘good’’intubationperformancewassignificantlyhigherin GroupGEBwhilethenumberofpatientswith‘‘poor’’intubationperformancewassignificantly higherinGroupILMA(p<0.05).

∗_{Corresponding}_author.

E-mail:[email protected](M.A.Yazar).

http://dx.doi.org/10.1016/j.bjane.2016.03.001

(2)

Conclusions: WeconcludethatGEB,whichischeapandeasilyaccessible,shouldbean advan-tageous choiceincervicaltrauma patients for boththeeaseness ofintubationandpatient morbidityandmortality.

http://creativecommons.org/licenses/by-nc-nd/4.0/).

PALAVRAS-CHAVE Viaaéreadifícil; Traumacervical

ComparaçãodaeficáciadeintubaçãopormeiodeguiaintrodutorBougiedetubo endotraquealemáscaralaríngeaemintubaçãotraquealdepacientescomtrauma cervicalsimulado

Resumo

Objetivo: Nesteestudoavaliamosaeficáciadeintubac¸õespormeiodeguiaintrodutorBougie emáscaralaríngeaemintubac¸ãoendotraquealdepacientescomtraumacervicalsimulado.

Método: Foramincluídos no estudo134 pacientes. Colarcervical foicolocado em todosos pacientesparaumtraumacervicalsimulado.Ospacientesforamalocadosaleatoriamenteem trêsgrupos:GrupoNI(n=45)foisubmetidoàintubaçãocomlaringoscópioMacintosh;Grupo ITE(n=45)foisubmetidoàintubaçãocomguiaintrodutordetuboendotraquealeGrupoML (n=44)foisubmetidoàintubaçãocommáscaralaríngea.Númerodetentativasdeintubação, sucessodeintubação,tempodevisualizaçãocompletadalaringe,tempodeintubação,escore dedesempenhodousuário,alteraçõeshemodinâmicasecomplicaçõesobservadasforam reg-istrados.

Resultados: OsucessodaintubaçãonaprimeiratentativafoimaiornoGrupoITEemenorno grupoML.Aindaemrelaçãoaosucessodaintubação,astaxasdesucessoforam95,6%,84,4% e65,9%nosgruposITE,NIeML,respectivamente.Ostemposdevisualizaçãodalaringeede intubaçãoforammenoresnosgruposNIeITEquenoGrupo ML.Essadiferençafoi estatisti-camente significativa, p<0,05), enquantonão houvediferença significativaentreosGrupos NIeITE. Onúmerode pacientescombom desempenho naintubaçãofoisignificativamente maiornogrupoITE,enquantoonúmerodepacientescommaudesempenhonaintubaçãofoi significativamentemaiornogrupoML(p<0,05).

Conclusões: ConcluímosqueoITE,queébaratoefacilmenteacessível,deveserumaopc¸ão vantajosaempacientescomtraumacervical,tantopelafacilidadedeintubac¸ãoquantodevido àtaxademorbidadeemortalidadedospacientes.

http://creativecommons.org/licenses/by-nc-nd/4.0/).

Introduction

Endotrachealintubationisthefirstandthemostimportant invitationtoensuretheairwaysafetyinpatientundergoing generalanesthesia.Endotrachealintubatingindifficult air-wayconditionsismoreimportantforpatient’sairwaysafety. Someofthedifficultairwayconditionsarethelimitationof cervicalspinemovementandthecasesmustbekeptlimited neck movement. Neck movements must be particularly limitedinnecktraumapatients.Itis extremelyimportant toquicklyanduncomplicatedintubatethispatientfortheir vitalfunctions.Sovariousmethodshavebeensuggestedto intubatethispatient.Inthisstudies,weaimedtocompare theeffectivenessofFastrach-LMA(IntubatingLaringealMask Airway---ILMA)hasbeen developedforblindintubationin difficultairwayconditionsandGumElasticBougie(GEB).

Method

Afterlocalethicscommitteeapproval(theregistration pro-tocolnumber3449),thisstudywasperformedprospectively

attheAnkaraTrainingandResearchHospitalbetweenMarch andJune2011.135patientsscheduledforelectivesurgery, between18and65,ASAcriteriaI---II,wereincludedinthe study.Prodecureswereexplainedindetailtoallpatients. Patientswhohadhistoryofdifficultintubation,cervical pos-turaldisorders,undergoingcervicalsurgery,bodymassindex over 30kg·m−2_, _mallampati _score _III---IV, _thyromental

dis-tancelessthan6cm,riskofgastricaspirationandpregnant wasexcludedformstudy.

Themouthopening,thyromentaldistances,and Mallam-patiscoreswere recordedin thepreoperative assessment performedonedaybeforethesurgery.Thecasesweretaken totheoperatingroomwithoutanypremedicationandwere monitored with regard to Electrocardiogram (ECG), non-invasive blood pressure, pulse oximeter, and EtCO2. The

patientsweresplitintothreegroupsandcervicalcollar (Stif-neckOriginalCollar,LaerdalMedicalCorporation,USA)was employedtoestablishsimulateddifficultintubation.After the removalof the collar, mouth opening was measured. Allthecasesinhaled100% O2 for3min (6L·min−1),

induc-tionwasestablished using1mcg·kg−1 _fentanyl_citrate_and

(3)

Figure1 Gumelasticbougie.

0.6mg·kg−1 _rocuronium _bromide. _The _{categorization} _into

groups was performed by random selection. Intubations were performed by a single anesthesiologist who had an experienceof more than 3 years.Each patient was cate-gorizedbyCormackLehane classificationwithout applying externalpressure.TheNIgroup(NormalIntubation)(n=45) were intubated with a Macintosh® laryngoscope using a Saviour®endotrachealtube,whiletheGEBgroup(Gum Elas-ticBougie,Fig.1)(n=45)wereintubatedwiththehelpof aMacintosh® laryngoscopeandGEBusingaSaviour® endo-tracheal tube, and the ILMA Group (Intubating Laryngeal MaskAirway,Fig.2)(n=45)wereintubatedwithaFastrach LMA using a Saviour® endotracheal tube. The femaleand malepatientswereintubatedwithacuffof7---7.5mmand 7.5---8.5mm,respectively;theanesthesiamaintenancewas achivedby50%O2(2L·min−1),50%N2O(2L·min−1),and2%

sevoflurane.

The time for laryngoscope or ILMA insertion, total intubation time (time to monitoring of the EtCO2 in

the capnography), number of intubation attempts, and Cormack-Lehane classification were recorded. The inser-tionof the intubation tube into the trachea wasdeemed as ‘‘succesful’’; while failure to insert, insertion taking morethan 60s, or making morethan 2 attempts at intu-bation was recognized as an ‘‘unsuccessful’’ attempt. In unsuccessfulcases,thecervicalarmswereremovedandthe intubationwasperformedusingaMachintoshlaryngoscope. Thecasesrequiringanadditionalmethodwerenoted.The ‘‘operator performance assessment’’ of the anesthesiolo-gistperformingtheintubationwascategorizedas‘‘good’’,

Figure2 IntubatingLaryngealMaskAirway.

Table1 Demographicdataonthegroups.

NI(n=45) GEB(n=45) ILMA(n=44)

Sex(F/M) 27/18 27/18 28/16 Age(mean±SD) 46±2.7 50±2.7 48±2.7 BMI 26.6±2 26.9±2 26.8±2 ASAI/II 35/10 30/15 33/11 SMD(cm)

(mean±SD)

16.18±2.2 16.73±2.0 17.16±2.5

TMD(cm) (mean±SD)

7.42±0.5 7.47±0.6 7.48±1.0

MO(cm) (mean±SD)

5.0±0.63 5.0±0.61 5.0±0.64

Cormack-Lehane Classification

2.24±0.5 2.42±0.5 2.34±0.5

BMI,bodymassindex;SMD,sternomentaldistance;TMD, tiro-mentaldistance;MO,mouthopening(whileinsertedcolar);SD, standarddeviation.

‘‘moderate’’,and‘‘poor’’.Thecomplicationsarisingduring intubation(mucosaldamage,dentaltrauma,lipinjury,torn cuff,hypoxia(SpO2<95%),andesophagealintubation)were

recorded.Subsequent tointubation, presenceof bloodon theEndotrachealTube(ETT)cufforanysignofsorethroat expressedbythepatientafterrecoverywerenoted,aswell. Hemodynamicparametersweremonitored throughout the entireoperationandrecordedbeforeinduction,rightafter induction,andatevery5minfor15min.

Statisticalanalysis

‘‘SPSSforWindows16.0.1’’packageprogramwasusedfor the statisticalanalysis. The studydata wereexpressedas mean,standarddeviation,percentage,andnumericvalues. Theintergroupcomparisonsofthemeasureddatawere per-formed by the Mann---Whitney U test and the intragroup comparisons were carried out by the Wilcoxon test. The comparisons of the countable data were performed by the Chi-square test; p<0.05 was recognized as statis-ticallysignificant.

Results

(4)

Table 2 Distribution of intubation attempts between groups.

NI (n=45)

GEB (n=45)

ILMA (n=44)

p

1Attempt 30(66%) 42(93%) 20(45%) 0.00 2Attempt 14(31.1%) 2(4.4%) 20(45%) 0.00 3Attempt 1(2.2%) 1(2.2%) 4(9.1%) 0.00

Table3 Intubationsuccessofthegroups.

NI (n=45)

GEB (n=45)

ILMA (n=44)

p

Successful intubation (n)

38(84.4%) 43(95.6%) 29(65.9%) 0.001

Unsuccessful intubation (n)

7(15.6%) 2(4.4%) 15(34.1%) 0.001

Note:Exceeding60sfordurationofintubationandattempting morethantwicefornumberofintubationhavebeenaccepted as‘‘unsuccessfulIntubation’’.

Table4 Laryngealvisualizationtimeandintubationtime betweengroups.

Laryngeal visualization time(s) (mean±SD)

14.4±0.7 12.6±1.0 43.7±0.8a,b

Intubationtime (s)

(mean±SD)

41.0±1.1 36.0±0.6 92.0±1.0a,b

The duration of insertion of ILMA into the mouth has been acceptedaslaryngealvisualizationtimeintheILMAgroup.

a _ILMA_group_vs._NI_group:_p_<_0.05. b _ILMA_group_vs._GEB_group:_p_<_0.05.

procedurewasdeemedunsuccessful in2of 44patientsin theGEBgroupandin5of44patientsintheNIgroupbecause theintubationtimewasmorethan60s.IntheILMAgroup, thistimewasprolongedin21of40patients.Therefore,the success rate for intubation was 95.6% (n=43) in the GEB group,84.4%intheNI group(n=38),and65.9% (n=29)in theILMAgroup(Caseswithmorethan2attemptsat intuba-tionorthosewithanintubationtimehigherthan60swere deemedunsuccessful).Theintergroupdifferencewasfound tobestatisticallysignificant(p<0.05).Theintubation suc-cess rates of the groups are shown in Table 3. Regarding thevisualizationoflarynxandintubationtime,NIandGEB groupsdemonstratedshortertimesthantheILMAgroup.This differencewasstatistically significant (p<0.05), however, therewasnosignificantdifferencebetweentheNIandGEB groups in this regard. Laryngeal visualization and intuba-tiontime relativetogroups are shown inTable 4. By the anesthesiologist,theintubationperformanceswere catego-rized as‘‘good’’, ‘‘moderate’’,and‘‘poor’’. Accordingly, the‘‘good’’ performanceratewas86%(n=39)in theGEB group,66%(n=30)intheNIgroup,and47%(n=21)inthe

Table 5 The operator performance rates relative to groups.

Good(n) 30(66%)c ₃₉_(86%)a,b ₂₁_(47%)

Moderate(n) 8(17%) 4(8%) 10(22%)

Poor(n) 7(15%) 2(4%) 13(29%)b,c

a _NI_group_vs._GEB_group:_p_<_0.05. b _GEB_group_vs._ILMA_group:_p_<_0.05. c _NE_group_vs._ILMA_group:_p_<_0.05.

ILMAgroup.The‘‘good’’performanceratewassignificantly higherintheGEBgroup(p<0.05).

‘‘Poor’’ performance ratewas29% (n=13) inthe ILMA groupwhichwassignificantlyhigherthanthoseintheNIand GEBgroups(p<0.05).Theoperatorperformancerates rela-tivetogroupsareshowninTable5.Therewasnostatistically significantdifferencebetweenthethreegroupswithregard toSBP,DBP,HR,SpO2 andEtCO2 valuesbeforeintubation,

rightafterintubation,andat 5,10,and15min after intu-bation.Thedatainvolvingthesehemodynamicparameters areshowninTable6.Intermsofintubationcomplications suchashypoxia,laryngospasm,orlipinjury,onepatientin eachofILMAandNIgroupsdevelopedhypoxia,onepatient intheNIgroupdevelopedlipinjury,whileanotherexhibited laryngospasm.Itwasnecessarytoremovethecervicalcollar in2patientsineachofNIandGEBgroups,andin8patients intheILMAgroup.

ThetotalnumberofcomplicationsintheILMAgroupwas 15(34%), while it was3 (6%)and 6 (13%)in the GEBand NIgroups,respectively.Thedifferencebetweenthegroups wasstatisticallysignificant (p<0.05).Therewasno signif-icantdifferencebetweenthegroups relativetofrequency ofsorethroat.Theintraoperativecomplicationand postop-erativesorethroatvaluesrelativetothegroupsareshown inTable7.

Discussion

Inthisstudy,wecomparedthesuccess ratesofintubation withGEBand ILMAinpatients difficulttointubatedue to cervical limitation. GEB wasobserved to be more advan-tageous with regard to ease of intubation, as well as in patient morbidity and mortality. Patients with a cervical traumaareregardedasdifficultintubationcases.Thereare ongoingstudiesfordeterminingthebestintubationmethod inpatientssuspectedofhavingcervicaltrauma.1_Moreover,

variousmethodsarebeinginvestigatedsuchasawakeblind nasal, oral, or fiberoptic intubation2_; _direct _laryngoscopy

withheadandneckstabilization3_;_{cricothyrotomy,}_indirect

laryngoscopywithBullardlaryngoscopy,4_and_blind_oral

intu-bationwithAugustineguide5_and_Combitube.6

(5)

Table6 Thehemodynamicparametersofgroups.

NI GEB ILMA

SBP (mmHg) (mean±SD)

BI 113.9±17.4 117.2±16.5 109.4±18.7

0min. 145.5±20.2 149.5±22.0 141.9±17.8 5min. 132.9±19.5 134.1±18.2 130.4±18.4 10min. 122.2±16.8 126.3±17.1 121.5±15.0 15min. 113.4±14.4 115.4±14.3 114.1±11.4

DBP (mmHg) (mean±SD)

BI 72.0±9.9 73.6±11.8 70.1±11.9

0min. 80.0±14.3 92.9±11.0 90.5±9.1

5min. 83.5±12.1 83.8±13.3 83.5±9.8

10min. 73.8±15.8 73.6±16.4 75.2±9.3

15min. 67.4±8.2 69.5±12.7 69.5±7.9

HR

(beat/min.) (mean±SD)

BI 69.4±10.8 72.0±13.8 69.3±8.8

0min. 89.6±11.4 91.0±13.3 86.4±9.2

5min. 84.1±11.5 85.2±13.6 83.3±8.5

10min. 79.6±10.4 80.0±13.3 79.5±8.6

15min. 73.3±8.9 73.4±12.7 73.0±6.7

SpO2%

(mean±SD)

BI 98.5±0.9 98.8±1.0 99.1±0.9

0min. 98.3±1.7 99.1±0.7 99.1±1.0

5.min. 98.2±1.8 98.9±1.5 99.1±1.0

10min. 98.2±1.6 96.9±14.8 97.5±1.0

15min. 98.3±1.4 99.0±0.8 99.1±0.9

EtCO2

(mmHg) (mean±SD)

BI 28.8±1.5 28.2±1.7 28.0±1.5

0min. 30.5±1.6 30.1±2.3 29.7±1.9

5min. 31.0±1.4 30.7±2.2 32.0±1.0

10min. 31.4±1.1 30.8±2.2 30.5±1.8

15min. 31.5±1.2 30.6±2.0 31.0±1.5

SBP,systolicbloodpressure;DBP,diastolicbloodpressure;HR,heartrate;SpO2,oxygensaturation;EtCO2,end-tidalcarbondioxide;BI,

beforeintubation.

Table7 Theintraoperativecomplicationandpostoperativesorethroatvaluesrelativetothegroups.

NI(n=45) GEB(n=45) ILMA(n=44) p

Intraoperativecomplications(+/−)(n,%) 6(13)/39(86) 3(6)/42(93) 15(34)/29(65) 0.02a

Postoperativesorethroat(+/−)(n,%) 29(64)/16(35) 33(73)/12(26) 22(50)/22(50) 0.07

(+/−),complicationpresent/complicationabsent.

a_ILMA_group_vs._GEB_and_NI_group:_p_<_0.05.

Theprotectionofthecervicalspinefollowingtraumais anessentialpartofpatientmanagement.Advancedtrauma lifesupportrequiresthecontinuouscervicalimmobilization ofpatientsbyasemi-rigidcervicalcollar.Thecollarshould notberemoveduntilrulingoutsignificantnecktrauma.In suchpatientsrequiring intubation,fiberoptic intubationis thebestchoice.However,intubationisoftenanemergency procedure that is carried out under stressful conditions far fromideal. It is difficult toapply direct laryngoscopy in patients with cervical collar, and generally it cannot beperformed. The use of semi-rigid collarsincreasesthe Cormack---Lehanegrade 3and 4laryngoscopicviewduring directlaryngoscopy,whilereducingthemouthopening.7_To

ensureoptimalviewindirectlaryngoscopy,manualin-line stabilizationisanalternativetechnique.Insuchcases,the collarshouldberemovedwithminimalcervicalmovement byanexperiencedtraumateamandtheneckofthepatient shouldbekeptinin-linepositiononafirmground.Afterthe intubation,thecollarshouldbeplacedagain.

Avidan et al.8 _compared _the _success _rates _of

ventila-tionandintubationusingdirectlaryngoscopyandtheILMA appliedonmanikin and patientsby inexperienced health-care workers who received a basic training before the intubation. The success rate of ILMA insertion was 100%, while the success rate of intubation using direct laryn-goscopy was84%,andthesuccess rateofintubationusing ILMAwas98%inmanikins.Ontheotherhand, thesuccess ratesofILMAinsertion,intubationusingdirectlaryngoscopy, and intubation using ILMA were 100%, 35%, and 43% in patients, respectively. Adequate ventilation wasachieved in78%ofpatientsinwhomafacemaskwasusedandin98% ofpatients inwhomILMAwasused.Thus,theyconcluded that ILMA could be useful in emergency oxygenation and ventilation, while also adding that their results were not supporting the use of ILMAby inexperienced personnel in advancedairwaymanagement.Waltletal.9_evaluated_the

(6)

successfulatfirstattemptin100%,intubationwithILMAwas succesfulin92.5%,intubationtimewithILMAatfirstattempt was39s(31---57),andintubationtimewithlaryngoscopywas 21s(16---34).ILMAwasfoundtocauselessextensionduring intubation ascompared todirect laryngoscopyand direct laryngoscopy wasobserved to provide rapid intubation in theabsenceofdifficultintubationconditions,however,ILMA wasprovidingfasterandsaferintubationindifficult intuba-tioncases.

Nileshwar et al.10 _evaluated _the _efficacy _of _Bullard

laryngoscopy vs. ILMA in patients withsimulated cervical immobilization andILMA was observed toprovide intuba-tionfasterthantheBL.Theintubationsuccessratewas90% intheBLgroupand74%intheILMAgroup;however,the dif-ferencewasnotstatisticallysignificant. Nakazawaetal.11

tested blind intubation withILMA in patients who under-wentcervicalspinesurgery.ILMAwassuccessfullyinserted in 100%, patients with a Halo bandagerequired a second attempt,successrateatfirstattemptwas60%inintubation withILMA,andtheprocedurefailedin10%ofthepatients. TheyreportedthatachievementofILMAinsertionand intu-bationwithILMAdidnotcauseheadandneckmovements, and theyassociated failureof blind intubation withusing impropermasksizes.Komatsuetal.12_evaluated_intubation

withILMAinpatientsofcervicalspinesurgerywitharigid collar and in normal surgery patients with nocollar. Col-lar usewasobservedtonarrow themouth opening,while increasingtheMallampatiscore.Overallintubationsuccess ratewas96%inpatientswithcollarand18%ofthepatients requiredmorethan2attempts.Intubationtimewas60sin patientswithcollarand50sinpatientswithnocollar.They reportedthat incases usingimmobilized rigidcollar, par-ticularlyinthosewhere fiberopticapproachisimpossible, intubationwithILMAmightbeasafeoptionfortheairway management.

InthestudyofBilginetal.,13_total_intubation_success_rate

was87%,thesuccessrateatfirstintubationattemptwas47% andthesuccessrateatsecondintubationattemptwas77% intheILMAgroup.TheILMAinsertiontimewas26.8sandthe totalintubationtimewithILMAwas70s.TheyreportedILMA asauseful deviceinthemanagementofdifficultairways. Beinetal.14 _conducted_a _study_on_patients_anticipated_to

showdifficultairwaymanagement.IntheILMAgroup, suc-cessful intubation rate at firstand second attempts were 70%and90%,respectively.Intubationcouldnotbeachieved in5%ofthepatients,whiletheILMAinsertiontimewas28s andtheILMAintubationtimewas70s.TheynotedILMAas anadvantageousdeviceinthemanagementofdifficult air-ways,aswell.Inanotherstudy,themedianblindintubation timewithILMAwas87s,totalsuccessratewas94%,while theratesofsuccessatfirstandsecondattemptswere67% and86%,respectively.15

In the present study, the results concerning the total success rates for ILMAinsertion, success rates relativeto number of attempts, ILMA insertion time,and intubation time with ILMA were comparable to the values reported in theliterature. The differences maybe associatedwith thestudy design,definitionofsuccess, anddetermination of the times. The significantly ‘‘poor’’ operator perfor-mancein ILMApatients isbelieved tobe arisingfromthe inadequacy ofILMA incases withcervical mobility limita-tion. In this study, success at first and second intubation

attemptswere95.6%and97.7%,whilethesuccessratewas 99.5% in theGEB group. Laryngeal visualization time was 12.6s and the intubation time was 36.0s. Regarding the operatorperformance,GEBapplicationwasgoodin86%and poorin4%.

GumElasticBougie(GEB)iscommonly usedin practice inthe UK. Theapplication of GEBin difficult oral intuba-tionhasbeen increasingoverthepast years.Whileit was used in 45% of difficult intubation cases in 1984, it was determined to be the first choice in 100% of such cases in1996;CardiffdescribesGEBasthemethodof choicein cases of difficult intubation.16 _When _the _{visualization} _of

theglottisis notgoodduringlaryngoscopy, GEBis recom-mended.Incasesofunanticipateddifficultintubation,use of GEBis claimedtoaccelerate the intubation process.17

VariousstudieshavenotedtheefficacyofGEBinthe man-agementofcasespresentingwithdifficultintubation.3,18,19

PatientsofCormack---Lehanegrade3havebeenreportedto haveaGEBsuccessrateof94---100%.17,19---21

Noguchietal.22 _compared_the_use _of_GEB_and_stylet_in

patientsreceivingcricoidpressure.Theyusedthemodified laryngealclassificationofCook.TheendotrachealGEB inser-tiontimeinpatientsanticipatedtopresenteasyintubation was12sandtheintubationtimewas31s.Inpatients antic-ipatedtopresent adifficult intubation, endotrachealGEB insertiontime was15s and the intubation timewas33s. Theynotedthatcricoidpressurewouldcomplicatethe tra-cheal intubation, while adding that GEB use wasan easy methodtoincreasethesuccessrateoftrachealintubation. InthestudyofKomatsuetal.,23_endotracheal_insertion_time

of GEB was 21s and the intubation time was 49s. Endo-tacheal GEB insertion was successful at first and second attemptsin73%and89.6%,respectively.Intubationwas suc-cessfulatfirstandsecondattempts in83.3%and95.8%of thepatients,respectively.OverallsuccessrateofGEBwas 89.6%.Messaetal.24_investigated_the_simplicity_and_success

ofintubationwithGEBinthemanagementofdifficult air-way.The successrateofintubationwithGEBwas94%and theintubationtimewas20.4s.Theyreportedahighsuccess ratefor GEB use in the managementof difficult airways. Inthepresent study,ourresultsconcerningGEBusewere comparabletotheonesreportedintheliterature.

Repeated attempts at intubation, aiming to maintain the airway safety may lead to higher complication rates includinghypoxia,pulmonaryaspiration,andhemodynamic sideeffects.25 _Repeated_intubation _attempts, _particularly

inpatientswithdifficultairway,mayalsoresultinlaryngeal perforationorpharyngealstricture.26_Therefore,_intubating

thepatientwithlessmanipulationandinshortertimeshould reducethecomplicationratestominimallevels.

Prolongedlaryngoscopyandintubationmaycausemany complications such as hypoxia and increased secretion. Particularly in the presence of indications complicating theintubationprocedure, each anesthesiologistshouldbe awareofthefactthatriskofprolongedorfailedintubation ishigh.

(7)

of the endotracheal tube, and removal of the ILMA. GEB requiresshortertimesbecauseGEBmanipulationissimpler thanILMAandML,leadingtoeasierlaryngealvisualization andendotrachealintubation.Inthepresentstudy,although wefoundshorterintubationtimesintheGEBgroupthanin theNIgroup,thedifferencewasnotstatisticallysignificant. Patientswitha cervical collar requiremore manipulation duringtheinsertionofILMAwhichhasanegativeeffecton thetimeandsuccessoftheintubationprocess.Owingtoits specialdesign,GEBrequireslessmanipulation.

Laryngoscopy andendotracheal intubation trigger sym-pathetic response by the mechanical stimulation of the larynxandtrachea,leadingtoincreasesintheplasma cat-echolamine levels which may in turn cause tachycardia, hypertension,arrhytmia,ormyocardialischemia.27_Factors

such as age, weight, and body mass index are known to influencethesuccessofandhemodynamicresponsestothe intubationprocess.

The ILMA may exert a pressure over the oropharygeal structures and cervical spine, leading to back slides in thecervicalvertebraeresultinginincreasedhemodynamic responseduetoraisedlevelsofstimulation.28_Moreover,_the

epiglotticelevatorof theILMA maystimulate periepiglot-ticstructures andarouse astrong hemodynamic response by affecting the supralaryngeal region known to be rich ofnociceptivereceptors.29 _In_addition,_while_removing_the

ILMA after intubation, the back and forth movement of the intubation tube may create a strong friction, leading toincreasedhemodynamicresponse,aswell.

Kiharaetal.30_categorized₇₅_normotensive_and₇₅

hyper-tensive patients into3 groups consisted of 25 patients in a randomized fashion; performed intubation using direct laryngoscopy, ‘‘lightwand’’, and ILMA; and recorded the hemodynamic data before and after induction, as well as before and after intubation. Although there was no differencebetween the groups in normotensive patients, hypertensive patients demonstrated a reduced hemody-namic response in the ILMA group. HR was observed to increase after the intubation as compared to baseline valuein all groups,however, therewasnosignificant dif-ference between the groups. The authors associated the reducedhemodynamicresponsewithlowerdegreeof recep-tor stimulation in that region. In the study of Baskett etal.31_conducted_on₅₀₀_patients,_hemodynamic_data_were

recordedafterinductionduringILMAinsertion,intubation, and ILMA removal. Mean HR and BP increased following theinsertion of the ILMA, anddemonstrated a significant increaseaftertheintubation,however,nosignificantchange wasobservedduringtheremoval.

Inthe presentstudy,hemodynamic parametersshowed anincreaseat 0minascomparedtopreintubation values, while nodifferencewas determinedbetween the groups. Theintragroupincreaseswere notstatisticallysignificant; therefore,these raisedvalues werethoughttobenormal responsestointubation.Albeitnotstatistical;SBP,DBP,and HRwereclinicallylowerat0minintheILMAgroup,which wasassociatedwiththepresenceoflessstimulationinthat region,sinceitisknownthatanadvantageofintubationwith ILMAisthatitdoesnotstimulatethebaseoftongue, epiglot-tis, and pharyngeal receptors. Therefore, cardiovascular responsetoendotrachealintubationwithILMAisexpected tobelow.32

In this study, no significant difference was observed betweenthegroupswithregardtopreintubationand postin-tubationlevelsofSpO2vs.EtCO2.Onlyonepatientineach

of ILMA and NI groups developed hypoxia. Although intu-bation times were significantly longer in the ILMA group as compared to NI and GEB groups, the unchanged SpO2

vs. EtCO2 values were explained with the absence of

a significantly prolonged intubation time. The reason is the entire FRC (approximately 2300mL) comprises O2 in

patientsreceiving100%oxygenfor2minasastandard pro-cedure for preoxygenationwhich delayshypoxia following apnea 4---5min.33 _Both _the _changes _in _the _hemodynamic

parametersandourresults concerningtheSpO2 vs.EtCO2

levels were consistent with those reported in the litera-ture.

Manycomplicationsmayariseduringintubationsuchas traumatothelip,dentalandmucosalinjuries,and desatura-tion.Also,pharyngealstructuresmaybedamagedinblind intubation with ILMA. In the literature, there are studies reportingdevelopmentofedemaintheepiglottisfollowing blindintubation.34_Moreover,_there_is_a_study_reporting_the

deathofapatientduetoesopharyngealperforationbecause ofblindintubation.35 _It_is_not_easy_to_evaluate

postopera-tivesorethroatincidenceofILMA,36_however,_some_studies

recognizethatthisincidenceisupto67%.37_However,_some

studieshave foundnosignificantdifferencebetweenILMA anddirectlaryngoscopywithregard topostoperative sore throat.38

Bilginetal.13_observed_higher_rates_of_{postoperative}_sore

throatintheILMAgroupandexplainedthiswiththe neces-sity toapplymoremanipulation.In theirstudy,Nileshwar etal.10_compared_ILMA_and_BL,_and_found_no_significant

dif-ference between the twogroups in terms of sore throat. Moreover, there was no significant intergroup difference withregardtointubation-relatedtrauma.Theyfoundblood onthe ETTin 2of 3cases whichrequired a third intuba-tion attempt in the BL group, while there was blood on theETTinallthepatientsthatrequiredathirdintubation attemptintheILMAgroup.Theyassociatedthisfindingwith higherincidenceofsofttissuetraumainpatientsneedinga thirdintubationattempt.

Inthe present study,2 patients in each ofNI and GEB groups,and8patientsintheILMAgroupcouldbeintubated aftertheremovalofthecervicalcollar;onepatientineach of ILMAand NI groups developedhypoxia, while in theNI group, 1 patienthad lip injury and one patientexhibited laryngospasm.ThecomplicationsintheILMAgroupshowed significant differences as compared to the NI and GEB groups, whichwasafindingconsistentwiththestudies of Baskettetal.31_and_Choyce_et_al.32_{Postoperative}_sore_throat

isoftenassociatedwiththenumberofmanipulations.25 _In

thepresentstudy,therewasnosignificantdifferencewith regardtopostoperativesorethroat.

Conclusion

(8)

Conflicts

of

interest

Theauthorsdeclarenoconflictsofinterest.

References

1.Hastings RH, Marks JD. Airway management for trauma patientswithpotentialcervicalspine injuries.Anesth Analg. 1991;73:471---82.

2.MeschinoA, Devitt JH,Koch JP, et al. Thesafety of awake tracheal intubation in cervical spine injury. Can J Anaesth. 1992;39:114---7.

3.NolanJP, WilsonME.Orotrachealintubation inpatientswith potentialcervicalspineinjuries.Anindicationforthegum elas-ticbougie.Anaesthesia.1993;48:630---3.

4.HastingsRH,VigilAC,HannaR,etal.Cervicalspinemovement during laryngoscopy with the Bullard. Macintosh, and Miller laryngoscopes.Anesthesiology.1995;82:859---69.

5.Fitzgerald RD, Krafft P, Skrbensky G, et al. Excursions of the cervical spine during tracheal intubation: blind oral intubation compared with direct laryngoscopy. Anaesthesia. 1994;49:111---5.

6.FrassM,FrenzerR,RauschaF,etal.Evaluationofesophageal trachealcombitubeincardiopulmonaryresuscitation.CritCare Med.1987;15:609---11.

7.ArslanZI, YildizT, Baykara ZN,etal. Tracheal intubation in patientswithrigidcollarimmobilisationofthecervicalspine:a comparisonofAirtraqandLMACTrachTMdevices.Anaesthesia. 2009;64:1332---6.

8.AvidanMS,HarveyA,ChitkaraN,etal.Theintubatinglaryngeal maskairwaycomparedwithdirectlaryngoscopy.BrJAnesth. 1999;83:615---7.

9.WaltlB,MelischekM,SchuschnigC,etal.Trachealintubation andcervicalspineexcursion:directlaryngoscopyvs.intubating laryngealmask.Anaesthesia.2001;56:221---6.

10.Nileshwar A, Thudamaladinne A. Comparison of intubating laryngealmaskairwayandBullardlaryngoscopefororo-tracheal intubationinadultpatientswithsimulatedlimitationofcervical movements.BrJAnesth.2007;99:292---6.

11.NakazawaK,TanakaN,IshikawaS,etal.UsingtheIntubating LaryngealMaskAirway(LMAFastrachTM)forBlindEndotracheal Intubation in Patients Undergoing Cervical Spine Operation. AnesthAnalg.1999;89:1319---21.

12.KomatsuR,NagataO,KamataK,etal.Theintubatinglaryngeal maskairwayallowstrachealintubationwhenthecervicalspine isimmobilizedbyarigidcollar.Anaesthesia.2004;93:655---9.

13.Bilgin H, Bozkurt M. Tracheal intubation using the ILMA, C-TrachTMorMcCoylaryngoscopeinpatientswithsimulated cervicalspineinjury.Anaesthesia.2006;61:685---91.

14.Bein B, Worthmann F, Scholz F,et al. A comparison of the intubatinglaryngeal mask airway and the Bonfils intubation fibrescopeinpatientswithpredicteddifficultairways. Anaes-thesia.2004;59:668---74.

15.LangeronO, SemjenF,BourgainJL,etal.Comparisonofthe intubatinglaryngealmaskairwaywiththefiberopticintubation in anticipated difficult airway management. Anesthesiology. 2001;94:968---72.

16.Turley A, Latto IP. Cardiff airway management audit. In: ProceedingsofDifficultAirwaySocietyAnnualMeeting.1996.

17.GataurePS,VaughanRS,LattoIP.Simulateddifficultintubation. Comparisonofthegumelasticbougieandthestylet. Anaesthe-sia.1996;51:935---8.

18.KiddJF,DysonA,LattoIP.Successfuldifficultintubation.Useof thegumelasticbougie.Anaesthesia.1988;43:437---8.

19.NolanJP,WilsonME.Anevaluationofthegumelasticbougie. Intubation times and incidence of sore throat. Anaesthesia. 1992;47:878---81.

20.Marfin AG, Pandit JJ, Hames KC, et al. Use of the bougie in simulated difficult intubation. Comparison of sin-gleusebougiewithmultiple-usebougie.Anaesthesia.2003;58: 852---5.

21.HarveyK,DaviesR,EvansA,etal.Acomparisonoftheuseof TrachlightandEschmannmultiple-useintroducerinsimulated difficultintubation.EurJAnaesthesiol.2007;24:76---81.

22.NoguchiT,KogaK,ShigaY,etal.Thegumelasticbougieases trachealintubationwhileapplyingcricoidpressurecompared toastylet.CanJAnesth.2003;50:712---7.

23.Komatsu R,Kamata K,Hoshi I,etal. Airwayscope and gum elasticbougiewithMacintoshlaryngoscopefortracheal intu-bationinpatientswithsimulatedrestrictedneckmobility.BrJ Anaesth.2008;101:863---9.

24.Messa MJ, Kupas DF, Dunham DL. Comparison of bougıe-assıstedıntubatıonwıthtraditionalendotrachealintubationin a sımulated diffıcult airway. Prehosp Emerg Care. 2011;15: 30---3.

25.Mort TC.Emergency trachealintubation:complications asso-ciated withrepeated laryngoscopic attempts. Anesth Analg. 2004;99:607---13.

26.KoscielnyS, GottschallR.Perforation ofthe hypopharynxas ararelifethreateningcomplicationofendotrachealintubation. Anaesthesist.2006;55:45---52.

27.Collins VJ. Principles of anesthesia; endotracheal anesthe-sia complications. 3rd ed. Philedelphia: Lea-Febirger; 1993. p.571---5.

28.Keller C,Brimacombe J,Keller K. Pressures exertedagainst thecervicalvertebraebythestandardandintubatinglaryngeal maskairway.AnesthAnalg.1999;89:1296---300.

29.HamayaY,DohiS.Differencesincardiovascularresponseto air-waystimulationatdifferentsitesandblockadeoftheresponses bylidocaine.Anesthesiology.2000;93:95---103.

30.KiharaS, Brimacombe J, Yaguchi Y. Hemodynamic responses amongthreetrachealintubationdevicesinnormotensiveand hypertensivepatients.AnesthAnalg.2003;96:890---5.

31.BaskettPJF,ParrMJA,NolanP.Theintubatinglaryngealmask. Anaesthesia.1998;53:1174---9.

32.Choyce A, Avidan MS, Harvey A, et al. The cardiovascular responsetoinsertionoftheintubatinglaryngealmaskairway. Anaesthesia.2002;57:330---3.

33.Airwaymanagement.MorganGE,MikhailMS,MurrayMJ,editors. Clinical anesthesiology. 4th ed. International Edition: Lange MedicalBooks;2006.p.504.

34.Takenaka I,Aoyama K, NagaokaE, et al. Malpositionofthe epiglottisaftertrachealintubationviatheintubatinglaryngeal mask.BrJAnesth.1999;83:962---3.

35.BranthwaiteMA.Anunexpectedcomplicationoftheintubating larygealmask.Anaesthesia.1999;54:166---7.

36.CaponasG.Intubatinglaryngealmaskairway(review).Anaesth IntensiveCare.2002;30:551---69.

37.ShungJ,AvidanMS,IngR,etal.Awakeintubationofthedifficult airwaywiththeintubatinglaryngealmaskairway.Anaesthesia. 1999;53:645---9.