Braz. j. . vol.80 número5

(1)

Brazilian

Journal

of

OTORHINOLARYNGOLOGY

www.bjorl.org

ORIGINAL

ARTICLE

Balloon

laryngoplasty

for

acquired

subglottic

stenosis

in

children:

predictive

factors

for

success

夽

,

夽夽

Rebecca

Maunsell

a

_,

_Melissa

_A.G.

_Avelino

b,c,d,∗

a_Hospital_de_Sumaré,_Universidade_Estadual_de_Campinas_(UNICAMP),_Campinas,_SP,_Brazil b_Pontifícia_Universidade_Católica_de_Goiás_(PUC-GO),_Goiânia,_GO,_Brazil

c_Hospital_da_Crianc¸a_de_Goiânia,_Goiânia,_GO,_Brazil d_Universidade_Federal_de_Goiás_(UFG),_Goiânia,_GO,_Brazil

Received11December2013;accepted24May2014 Availableonline23July2014

KEYWORDS

Laryngostenosis; Laryngoplasty; Dilatation; Child

Abstract

Introduction:The treatment ofsubglottic stenosisin children remainsa challenge for the otorhinolaryngologist,andmayinvolvebothendoscopicandopensurgery.

Objective: Toreportthe experience oftwo tertiary facilities inthe treatment ofacquired subglotticstenosisinchildrenwithballoonlaryngoplasty,andtoidentifypredictivefactorsfor successofthetechniqueanditscomplications.

Methods:Descriptive,prospectivestudyofchildrendiagnosedwithacquiredsubglotticstenosis andsubmittedtoballoonlaryngoplastyasprimarytreatment.

Results:Balloonlaryngoplastywasperformedin37childrenwithanaverageageof22.5months; 24presentedchronicsubglotticstenosisand13acutesubglotticstenosis.Successrateswere 100%foracutesubglotticstenosisand32%forchronicsubglotticstenosis.Successwas signifi-cantlyassociatedwithacutestenosis,initialgradeofstenosis,childrenofasmallerage,and theabsenceoftracheostomy.Transitorydysphagiawastheonlycomplicationobservedinthree children.

Conclusion: Balloonlaryngoplastymaybeconsideredthefirstlineoftreatmentforacquired subglotticstenosis.Inacutecases,thesuccessrateis100%,andalthoughtheresultsareless promisinginchroniccases,complicationsarenotsignificantandthepossibilityofopensurgery remainswithoutprejudice.

夽 _Please_cite_this_article_as:_Maunsell_R,_Avelino_MA._Balloon_{laryngoplasty}_for_acquired_subglottic_stenosis_in_children:_predictive_factors forsuccess.BrazJOtorhinolaryngol.2014;80:409---15.

夽夽

Institution:UniversidadeFederaldeGoiás(UFG),Goiânia,GO,Brazil.

∗_{Corresponding}_author.

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

http://dx.doi.org/10.1016/j.bjorl.2014.07.012

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PALAVRAS-CHAVE

Laringoestenose; Laringoplastia; Dilatac¸ão; Crianc¸a

Laringoplastiacombalãoparaestenosesub-glóticaadquiridanainfância:fatores preditivosdesucesso

Resumo

Introduc¸ão:Otratamentodasestenosessubglóticasemcrianc¸asaindarepresentaumdesafio paraootorrinolaringologista,epodeenvolvertantoprocedimentosendoscópicosquanto cirur-giasreconstrutivasabertas.

Objetivo:Apresentaraexperiênciadedoisserviçosterciáriosnomanejodasestenoses subglóti-casadquiridasemcrianças,atravésdalaringoplastiacombalãoeidentificarfatorespreditivos desucessoeascomplicações.

Método: Estudodescritivoprospectivodecrianc¸ascomestenosesubglóticaadquirida submeti-dasàlaringoplastiacombalãocomotratamentoprimário.

Resultados: Foramincluídas37crianças(médiadeidade22,5meses):24criançasportadoras deestenosesubglóticacrônicae13deestenosesubglóticaaguda.Ataxadesucessodo trata-mentofoide100%paraoscasosagudose32%paraoscasoscrônicos.Osucessodotratamento tevecorrelaçãosignificativacom:tempo deevoluçãodaestenose,grauinicial daestenose, menoridadedascriançaseaausênciadetraqueostomiaprévia.Disfagiatransitóriafoiaúnica complicaçãoobservadaemtrêspacientes.

Conclusão:Alaringoplastiacombalãopodeserconsideradacomoprimeiralinhadetratamento nasestenosessubglóticas.Noscasosagudosataxadesucessoéde100%eoganho,mesmoque parcialnoscasoscrônicos,éinsento decomplicac¸õessignificativasenãotrazprejuízopara cirurgiasreconstrutivasposteriores.

Introduction

Inrecentyears,therehasbeenareductionofmortalityin neonatalintensive care units (ICUs) due tothe impactof recenttechnologicaladvancesintheperinatalarea.1 _As_a

consequence,prolongedorotrachealintubationincreasedin

frequency,andincontrasttoadults,inwhomtracheostomy

isawellestablishedprocedureforthesecases,inthe

pedi-atricagegroupthisindicationiscomplex.2

Thus,anincreaseinacquiredsubglotticstenosis(SGS)has

beenobservedinchildren.SGSisanarrowingofendolarynx,

representingoneofthemostcommoncausesofstridorand

respiratorydistressinchildren.Thepediatricpopulationis

themostcommonlyaffected,becausethisisthenarrowest

regionoftheairwayatthisage.SGSmaybecongenitalor

acquired.Theacquiredformisresponsiblefor90%ofcases

ofsubglotticnarrowinginchildrenandisusuallysecondary

toprolongedtrachealintubation.

The treatment of acquired stenosis may involve

endo-scopicprocedures,bothintheacutephaseandthechronic

phase.Withinthearsenalofendoscopicprocedures,theuse

ofballoon dilatation or balloon laryngoplastyis becoming

popularacrosstheworldasaprimarytherapeuticoption.3_In

theacutephase,oneoftherapeuticoptionsistracheostomy.

Despitetheimmediateresolutionofrespiratoryfailure,the

necessarycare,mainlyinthecase ofsucklinginfantswith

tracheostomy,isconsiderable,causingmuchanguish,fear,

andsociallimitationforcaregiversandforthechild.Therisk

of obstruction of the tracheostomy tube inside and

espe-cially outside the hospitalsetting cannot beignored, nor

theriskofdeath.Furthermore,thetracheostomyitselfcan

createadditionalcomplicationstotheairway,suchas

col-lapse,stenosis,andpersistenttrachealgranulationtissue.4

Itmust alsobeconsidered that tracheostomydoes not

solvethe problem ofhealing of theinflammatory process

alreadyembeddedinthesubglotticregion,andoften

chil-dren withtracheostomy after an intubation for laryngitis

evolvetoSGSthatisonlydiagnosedlater.

In chronic SGS, open surgeries for laryngeal

recon-struction, when carefully planned, exhibit high rates of

resolution. However, these procedures require the

coor-dination of an experienced team for postoperative care,

involving sedationweaningandthemanagementof

unsta-bleairways.Moreover,theseoperationsinvolverisksofgraft

infection,dehiscence,sepsis,andrestenosis,whichshould

not be underestimated. Thus, the management of these

patientsremainsabonafidechallengetothe

otorhinolaryn-gologist.

Balloon dilatation has been usedto treat laryngeal or

tracheal stenosis in children as early as the 1980s, with

encouragingresults.5_The_main_advantage_of_this_technique,

incomparisonwithothermethodsofendoscopicdilatation

withtracheal tubesand dilators,isthe possibilityto

pro-motean outwardexpansion,eveninthepresence ofvery

reducedlumen.Itisspeculatedthatitsuse,incomparison

withothermethodsofdilatation,promoteslesstissueinjury

and,thus,lessscarformation.

In a systematic review and meta-analysis in 2013 on

balloon laryngoplasty in cases of pediatric SGS, Lang and

Brietzke3 _concluded_that_this_treatment _has_a_good

short-termsuccessrate,withrarecomplications;andthatfailures

(3)

The objectiveof thepresentstudywastodemonstrate

theexperienceoftwotertiaryservicesinthemanagement

of SGS secondary to tracheal intubation in children, with

balloonlaryngoplastyasaprimarytreatment,andtorelate

thepredictorsoftechnicalfailureanditscomplications.

Methods

This was a prospective, descriptive study of children

diagnosed with acquired SGS after tracheal intubation,

undergoing balloon laryngoplasty as a primary treatment

fromAugustof 2011toSeptemberof 2013in two

depart-ments of otorhinolaryngology in tertiary hospitals. The

procedureswereperformedineach oftheservicesbythe

same surgeons, with training and experience in pediatric

airwaymanagement.

Patientsolderthan14years,withlessthanthreemonths

of follow-up, undergoing other previous laryngeal

proce-dures,withcongenitallaryngealstenosis,andthosewhose

parentsor guardiansrefusedtosigntheinformedconsent

wereexcluded.

Thisstudywasapprovedbytheethicscommitteesofeach

departmentundernumbers 002/2011and001/2011. After

beinginformedabouttheprocedureanditsrisks,allparents

orguardianssignedaninformedconsent.

Allenrolled patientswereevaluatedfor age,lengthof

stenosis,numberofdilatations,degreeofinitialsubglottic

stenosis,andpresenceoftracheostomy.

The childrenwerefurtherdividedintotwogroups: the

groupofchronicSGS,i.e.,childrenunderdilatationofSGS

in a period >30 days fromthe onset of symptoms of SGS

and/or from diagnosis, and the group of acute SGS, i.e.,

thosechildrendilatedintheperiod≤30daysfromtheonset

ofsymptomsorfromdiagnosisofSGS.

The degreeofsubglotticstenosis wasdeterminedusing

theclassificationofMyerandCotton,6_which_was_obtained

afterbronchoscopy usinga 0-degreerigid endoscopewith

a diameter ranging from 2.7mm to 4mm. Retrograde

endoscopywithMachida® _3.2_mm_flexible _fiber_endoscope

was also performed in patients undergoing tracheostomy

whenitwasnotpossibletopasstherigidendoscopethrough

thestricture,thusallowingabetterstagingofthedegree

ofacquiredSGS.

Thedilatationswerealwaysperformedwiththepatient

under general anesthesia, spontaneous ventilation, and

intermittent apnea during balloon inflation, as needed.

Vascular balloons of three different brands (Acclarent®_,

Boston®_,_and_E._Tamussino®₎_were_used,_always_with_a_length

of20---30mm.Thediametersoftheballoonsvaried

accord-ingtothechild’sage.Generally,theoutsidediameterofthe

most suitable endotracheal tube was considered for each

child,addingapproximately2mmtodeterminethe

diame-teroftheballoon.Thetimeandnumberofinflationsvaried

according tosizeof the airway, aswellas thepulmonary

reserve of the child and/or the perception of

supraglot-tic/glottic edema secondary to dilatation. Generally, the

maintenance time of the inflated balloon did not exceed

1.5min,andtheinflationswererepeatedthreetimes.The

inflationpressureoftheballoonsrangedfrom3to15mmHg

withaprogressivetendencyfortheuseofhigherpressures

in the last year, after analyzing reports and personal

Figure1 Balloonduringdilatation.Childduringballoon laryn-goplasty.

communicationsfromothercolleagueswithrenowned

expe-rienceinthesubject,especiallyinthemostextensiveand

chronicstenoses.Thetimeelapsedbetweendilatation

pro-ceduresranged from15 to60 days,due toavailabilityof

surgicaltimeandpossibleclinicalcomplications,orthelack

offavorableconditionsforgeneralanesthesia.

All pre- and post-dilatation endoscopies were

docu-mented, aswell as a detailed description in the medical

record regarding the post-procedural outcomes and the

occurrenceofcomplications.

Treatmentwasconsideredsuccessfulinpatientswho,in

thestudyperiod,weredecannulatedand/orhadnofurther

signsorsymptomsofdiscomfort,eveninthefaceofresidual

stenosis.

To correlate the predictors of successful outcomes,

a statistical analysis was performed using nonparametric

Mann---WhitneyUandFisher’sexacttests,withasignificance

levelsetat0.05.

Results

Atotalof37childrenwhounderwentballoonlaryngoplasty

(Fig. 1) were included in the study; 24 had chronic SGS

(Fig.2)and13 hadacuteSGS(Fig.3).Themeanage was

22.5months(range:1monthto11years)(Table1).Twoof

24patientswithchronicSGSand10of13patientswithacute

SGSwerenottracheostomized.AstothedegreeofSGS,two

patientshadgradeI,fivehadgradeII,and30hadgradeIII.

Thenumberofdilatationsrangedfromonetofive,witha

meanof2.5proceduresperpatient.Threepatientshad

dys-phagiaasacomplicationimmediatelyaftertheprocedure;

thedysphagiawastransient, resolvingin lessthan 24h in

twocases;inonecase,itwaspersistent,requiringtheuse

ofanasoenterictubeforaperiodofthreeweeks.

Inthegroup ofchronic stenoses,themeandurationof

thestenosiswas22months(minimumofthreemonths,and

(4)

Table1 Descriptionofcaseswithdataregardingage,durationofthedisease,presenceoftracheostomy,degreeofstenosis, numberofdilatations,andtherapeuticsuccess.

Age(months) Progressiontime Tracheostomy SGSgrade Dilatations(n) Success

18 Chronic Yes III 5 Yes

56 Chronic Yes III 2 No

132 Chronic No III 3 Yes

16 Chronic Yes II 1 Yes

16 Chronic Yes I 2 Yes

31 Chronic No III 1 Yes

2 Acute No I 1 Yes

1.5 Acute No II 2 Yes

2.5 Acute No III 2 Yes

15 Acute No III 2 Yes

8 Acute Yes III 3 Yes

2 Acute No II 2 Yes

1 Acute Yes III 5 Yes

1.5 Acute No II 1 Yes

16 Acute Yes II 2 Yes

1 Acute No II 2 Yes

Thesuccessratewas100%and32%foracuteandchronic stenoses,respectively(Fig.4).

Theminimumfollow-uptimewasthreemonths,witha

maximumof12months.

Correlating the patient’s age with the success of the

balloonlaryngoplasty technique,it wasobserved thatthe

youngerthechild,thehigherthesuccessrate(Fig.5).

Correlatingthepresenceoftracheostomyatthetimeof

theprocedurewithproceduralsuccess,itwasobservedthat

non-tracheostomizedpatientshadhigherchancesofsuccess

withtheprocedure(Fig.6).

Correlatingthedegreeofsubglotticstenosisand

proce-duralsuccess,itwasobservedthatthehigherthedegreeof

thestenosis,thegreaterthechancesoffailure(Fig.7).

Correlating the number of dilatations and the success

ofthetechnique,nostatisticallysignificantcorrelationwas

observed(Fig.8).

Correlatingtheprogressiontimeofsubglotticstenosisin

bothgroups,itwasfoundthatgroup1(children>30daysof

stenosis[chronicSGS])hadhigherchancesoffailure(Fig.4).

Inthegroupofchronicstenoses,nocorrelationbetween

progression, time of the stenosis, and success rate was

observed.

Discussion

Usually,thetreatmentofacquiredSGSinpediatricpatients

is a distressing and painful event both for patients and

their relatives. Inacute cases,the patientis hospitalized

andintubated,failingsuccessivelyinattemptsfor

extuba-tion;orsometimesthechildisextubated,butinastateof

respiratoryfailure.In chroniccases,thechild alreadyhas

(5)

Figure2 Chronicsubglotticstenosis.Childwithchronicgrade IIISGS,pre-dilatation.

oflaryngitisorasthma.Thesearechildrenwhorepeatedly

seek health services, often without receiving information

or referral toaprofessionalin apositiontomake a

diag-nosis and establish a sound treatment. The presence of

theotorhinolaryngologisttrainedintheevaluationof

pedi-atric airways and working next to pediatric and neonatal

ICUs is critical to change this scenario. Thus, it will be

possibletoestablishearlydiagnosesandproceduresaimed

at preventing the occurrence of acquired SGS. The

suc-cessofdilatation foracutestenoses,asshownin thisand

otherstudies,7---9_confirms_this_need._{Unfortunately,}_the

pro-cedure of tracheostomyhas been theonly alternative for

thesecases,intheabsenceofaproperevaluation.Despite

the immediate resolution of respiratory failure, the

nec-essary care, mainly in the case of suckling infants with

tracheostomy,isconsiderable,causingmuchanguish,fear,

andsociallimitationbothforcaregiversandfor thechild.

However,theriskoftracheostomytube obstructionandof

Figure3 Acutesubglotticstenosis.ChildwithacutegradeIII SGS,pre-dilatation.

Chronic Acute

Failure Successful 20

15

10

5

0

Figure 4 Correlation of patients in group 1 (chronic) and group2(acute)withthechancesofsuccesswithballoon laryn-goplasty.

Successful Failure

40

30

20

10

0

Age (months)

Figure5 Correlationbetweenpatientageandsuccessof bal-loonlaryngoplasty.

Tracheostomy+ Tracheostomy–

Failure Successful 20

15

10

5

0

Patients (n)

(6)

1

Successful Failure 20

15

10

5

0

2 3

0 0

7

11 16

2

G test: Independence

Figure7 Correlationbetweenthedegreeofstenosis accord-ing to Myer---Cotton and failures of balloon laryngoplasty (p=0.0015).

death cannot be ignored --- inside and especially outside

thehospital.Thus,aswasdemonstratedinthisstudy,

bal-loon laryngoplasty, besides being an excellent option for

childrenwithacuteSGS,couldpreventalarge numberof

tracheostomieswhich are unfortunately performed in the

pediatricpopulation,particularlyduringandafter

hospital-izationsinICUs.

Evenafterperformingatracheotomy,theinflammation

generated by the tracheal tube will heal, and

consider-ing that the respiratory condition was stabilized by the

1 10

8

6

4

0 2

3 2

4

5 7

6

G test: Independence

9

1 1

0

4 5

1 2

Successful Failure

Figure8 Correlationbetweenthenumberofdilatationsand balloonlaryngoplastysuccess.Nostatisticalsignificance.

tracheostomy, often the resultingscarringor stenosis will

beignoredforweeks,months,orevenyears.Insuchcases,

thestenosiswillbediagnosedlate.Inthesechroniccases,

thetherapeuticalternativesmayinvolveendoscopic

proce-duresorexternalsurgeries.Inthepresentstudy,itwasfound

thateveninchroniccases,thesubglotticstenosesmaybe

amenabletorelativelylessinvasivetreatments,suchas

bal-loon dilatation, although in thisstudy the success rate in

childrenwithchronicSGSwasonly32%.Theresultsreported

in theliterature for balloon laryngoplastydo not

discrim-inate among chronic and acute cases, but some authors8

suggest that the results would not be good.According to

thepresentresults,inchronicstenosiscasesthereseemsto

bearelationshipbetweentimeofstenosisprogressionand

therapeuticsuccesswithballoonlaryngoplasty.Thisseems

to be more related to the degree of stenosis and to the

characteristicsofthescar.Thesedatadiffersomewhatfrom

thosereportedbyWhighametal.10_In_2012,_these_authors10

suggestedthatfailureintheprimarytreatmentofstenoses

withballoondilatation isrelatedtoothercomorbiditiesin

theairways,andfoundnorelationshipbetweentherapeutic

successandageoftheirchildren,degreeofstenosis,andits

characteristics(softorfibrous),divergingfromthefindings

ofthepresentstudy,whichobservedbettersuccessratesfor

youngerchildrenandthosewithlowerdegreesofstenosis.

Thinorlaminarscarsappeartobemorepronetogoodresults

withballoon dilatation. This makessense,sincethe thick

andfibroticcartilaginousframeworkofthelarynxcannotbe

dilated.However,thisisonlyanimpressionoftheauthors,

andthisfindinghasnotbeenmeasuredinthepresentstudy.

In this study, the absence of prior tracheostomy had

sig-nificantcorrelationwiththesuccessoftheprocedure.This

findingmayreflectthegeneralhealthstateofthesechildren

who, despite showing severe stenosis, had no significant

comorbidities,inagreementwithliteraturereports.10

Although in this study thefailure of balloon dilatation

occurred in 68% of children treated for chronic SGS, it is

believedthatevenincaseswherethereisnopossibilityof

stenosis anddecannulation, theincrease ofthesubglottic

diameteratthecostofmucosalscartissuedilatationoften

allows vocalization. The possibility of vocal emission and

communicationsignificantlyimpactthequalityoflifeofthe

patientandof theirrelatives,whooften musttowaitfor

thecontrolofcomorbidities---which cantakemonthsand

sometimesyears---forprogramminganopenreconstruction

surgery.

Theprincipalattractivefeatureofballoonlaryngoplasty

istherelativeeaseofitsimplementationandthepossibility

ofitsuseeveninseverestenosis,consideringthediminutive

diameteroftheballoon,whichdifferentiatesitfromother

forms of dilatation. This techniquealso does not exclude

thepossibilityof anexternalreconstructivesurgeryinthe

caseoffailure;norwasitshowntocauseanincreaseinthe

scarred area,hindering subsequent treatments that were

performedin fivechildreninthisgroup.Thesuccessrates

ofballoonlaryngoplastyforprimarytreatmentofacquired

SGSvariesbetween60%10_and_100%11_in_the_literature.8,12---14

Recently,thegroupofBlanchardetal.13_suggested_even_the

primary treatment of congenital subglottic stenoses with

thismethod.

However, the dilatation of non-tracheostomized

(7)

with the glottis obstructed by a balloon can lead to

serious complications, such as pulmonary edema.

There-fore, it is essential to involve the surgical team with

the anesthesia team, so that spontaneous breathing and

apneas are coordinated during the procedure ---

espe-ciallyinnon-tracheostomizedchildren.Somechildrenhave

extremely reactive airways, and edema of the

supraglot-ticregion mayresult in transient cough anddysphagia as

clinical implications. Obstructiveconditions,secondary to

dilatation,werenotfoundinthisgroup,evenamong

non-tracheostomizedchildren.Transientdysphagiawasobserved

in only three children, representing an 8% incidence of

complications.Thiswasconsideredaminorcomplication,as

theseweretransientepisodes.Therewerenootherevents

orcomplicationsrelatedtoballoonlaryngoplasty.

Currently,the maindifficulties inlaryngoplastyballoon

proceduresrelateprincipallytothelackofstandardization,

mainlywithregardtothenumberofdilatations.Inthe

liter-ature,thereisnostandardizationwithrespecttodilatation

pressure,dilatationtime,intervalbetweendilatations,and

useofmoldsandoftopicalorinjectablemedications.The

authors’ impression is that the inflation pressure and the

duration of balloon inflation should be adjusted to each

patient,dependingontheobservationof reactiveedema.

Theballoonsusedhaveanindicationofmaximumdiameter

withrespecttoacertainpressure;therefore,toexceedthe

prescribedpressuredoesnotincreasetheexpansionofthe

airway,butonlyincreasestheriskofballoonbreakage,

ren-deringnewinflationsimpossible.Usually,theauthorsagree

that theballoon shouldbeinflated at least twice ineach

procedure.

An extremelyinterestingfindingobservedin thisseries

wasthelackofcorrelationbetweensuccessrateand

num-berofdilatations.Considerablecommonsenseiscalledfor

inordertoavoidperformingunnecessaryproceduresandthe

creationoffalseexpectationsoftherapeuticsuccessforthe

childandhis/herfamily.Videodocumentationandserial

cal-ibrationoftheairwaywithtrachealtubesatthebeginning

andendofeachprocedureprovidealittlemoreobjectivity

tothefollow-upofthesecases.Furthermore,theyallowthe

surgeontoactuallymaterializethebenefitsofintervention,

andtodeterminewhentostopthistreatmentandelectthe

reconstructivesurgerymostappropriateforthecase.

Conclusion

Balloonlaryngoplastycanbeconsideredasafirst-line

treat-mentin SGS,both acuteandchronic. Inacutecases, this

procedure was100% successful.In chronic cases the

ben-efits,evenpartial,were freeof significantcomplications,

withoutprejudicetofuturereconstructivesurgeries.

Thepredictivefactorsofsuccessinthisstudywere:

pres-enceofacutestenosis,dilatationatanearlyage,dilatation

intheabsenceofpriortracheostomy,andlesssevere(grade

IandII)stenoses.

Conflicts

of

interest

Theauthorsdeclarenoconflictsofinterest.

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