Rev. Bras. Anestesiol. vol.65 número5

RevBrasAnestesiol.2015;65(5):411---413

REVISTA

BRASILEIRA

DE

ANESTESIOLOGIA

www.sba.com.br

CLINICAL

INFORMATION

‘‘Loss

of

breath’’

as

a

cause

of

postoperative

hypoxia

and

bradycardia

in

children

submitted

to

tonsillectomy

Eduardo

Toshiyuki

Moro

_,

_Alexandre

_Palmeira

_Goulart

FaculdadedeCiênciasMédicasedaSaúde,PontifíciaUniversidadeCatólicadeSãoPaulo,SãoPaulo,SP,Brazil

Received7April2012;accepted22November2012 Availableonline11February2014

KEYWORDS

Apnea; Lossofbreath; Child;

Hypoxia; Bradycardia; Postanesthesia recovery

Abstract

Backgroundandobjectives: the‘‘shortnessofbreath’’or‘‘breathinginterruption’’crisiscan beconsideredacauseofhypoxiainchildhood.Itischaracterizedbythepresenceofatriggering factor followedby weepingandapneainexpirationaccompaniedbycyanosisorpallor.The sequence ofeventsmay includebradycardia,lossofconsciousness,abnormal postural tone andevenasystole.Areviewoftheliteraturerevealedonlytworeportsofpostoperativeapnea causedby‘‘shortnessofbreath’’.

Casereport: thisarticledescribesthecaseofachildwithahistoryof‘‘shortnessofbreath’’ undiagnosed before theadenotonsillectomy, but thatrepresented the causeofepisodes of hypoxemiaandbradycardiainthepostoperativeperiod.

Conclusions: the‘‘shortnessofbreath’’crisisshouldbeconsideredasapossiblecauseof peri-operative hypoxiainchildren,especiallywhenthereisahistorysuggestiveofthisproblem. Assomeeventsmaybeaccompaniedbybradycardia,lossofconsciousness,abnormalpostural toneandevenasystole,observationinahospitalsettingshouldbeconsidered.

© 2013SociedadeBrasileirade Anestesiologia.Publishedby ElsevierEditoraLtda.Allrights reserved.

PALAVRAS-CHAVE

Apneia;

Perdadefôlego; Crianc¸a; Hipóxia; Bradicardia; Recuperac¸ão pós-anestésica

‘‘Perdadefôlego’’comocausadehipóxiaebradicardiapós-operatóriaemcrianc¸a submetidaàamigdalectomia

Resumo

Justificativaeobjetivos: Acrisede‘‘perdadefôlego’’oude‘‘interrupc¸ãorespiratória’’pode ser consideradaumacausadehipóxianainfância. Écaracteriza pelapresenc¸ade umfator desencadeanteseguidoporchoroeapneiaemexpirac¸ãoacompanhadadecianoseou palidez-cutânea. A sequênciade eventos podeincluir bradicardia, perdada consciência, alterac¸ão do tônusposturaleatéassistolia. Uma revisãodaliteraturaevidenciouapenas doisrelatos deapneiapós-operatóriacausadapor‘‘perdadefôlego’’.

∗_{Correspondingauthor.}

E-mail:[email protected](E.T.Moro).

0104-0014/$–seefrontmatter©2013SociedadeBrasileiradeAnestesiologia.PublishedbyElsevierEditoraLtda.Allrightsreserved.

412 E.T.Moro,A.P.Goulart

Relatodocaso:Opresenteartigo descreveum casodecrianc¸aacomantecedentedecrises de‘‘perdadefôlego’’nãodiagnosticadasantesdafeituradeadenoamigdalectomia,masque representaramacausadeepisódiosdehipoxemiaebradicardianoperíodopós-operatório.

Conclusões:Ascrisesde‘‘perdadefôlego’’devemserconsideradascomopossívelcausade hipóxiaperioperatóriaemcrianc¸aas,principalmentequandoháhistóriapréviasugestiva.Como algunseventospodemseracompanhadosdebradicardia,perdadaconsciência,alterac¸ãodo tônusposturaleatéassistolia,aobservac¸ãoemambientehospitalardeveserconsiderada. ©2013SociedadeBrasileiradeAnestesiologia.PublicadoporElsevierEditoraLtda.Todosos direitosreservados.

Introduction

The‘‘shortnessofbreath’’or‘‘breathinginterruption’’’ cri-siscanbeconsideredacauseofhypoxiainchildhood.Itis characterizedbythepresenceofatriggeringfactorsuchas anxiety,fear,painorfrustration,followedbyweepingand apneainexpirationaccompaniedbycyanosisorpallor.The sequence ofevents may include bradycardia,loss of con-sciousness,abnormalposturaltoneandevenasystole.1,2_A

reviewoftheliteraturerevealedonlytworeportsof post-operativeapneacausedby‘‘shortnessofbreath’’.3,4

Case

report

Malechild,1yearand11monthsofage,evaluatedin pre-anestheticconsultationforanadenotonsillectomy,showed noabnormalities suggestive of systemic disease. Premed-icationwithmidazolam(0.5mgkg−1_{)PO20minbeforethe}

procedure.Intheoperatingroomthepatientwasmonitored with electrocardiogram (DII), pulse oximetry and nonin-vasive blood pressure. After administration of mixture of O2 by inhalationand N2O 60% andsevoflurane 6%by face mask,acatheter24Gwasinsertedbyvenoclysisafter induc-tionofanesthesiawithremifentanilincontinuousinfusion (0.5␮gkg−1min−1), propofol 3mgkg−1 and cisatracurium

0.1mgkg−1_{.Trachealintubationandinsertionofatubeof}

4mmwithballoonweredoneuneventfully.Thepatientwas maintained on mechanical ventilation in a closed system withreabsorptionofCO2andthenmonitoringofexpired car-bondioxide(PetCO2)wasadded.Theanesthesiawas main-tainedwithremifentanil(0.3␮gkg−1min−1)andsevoflurane

1---1.5%. The surgery lasted40min without complications. Thechildpresentedacalmawakening,about 10minafter stopping the infusion of anesthetic agents. Postoperative analgesiawasintroducedwithmorphine (0.1mgkg−1_)and

dipyrone (30mgkg−1_{). The child was transferred to the}

postanesthesiarecoveryroom(PARR),whereitstayedwith O2facemaskandmonitoringwithpulseoximetry.Duringthe permanenceinPARRandaftertheexpectedinitialagitation forthefirst30minaftertheprocedure,thepatienthad peri-odsofcalmandagitation,withoutevidentbleedingandwith apain consideredof mild tomoderate intensity. Approxi-mately3hafterthetransferencetoPARR,thechildshowed cyanosis and muscle hypertonia which resolved sponta-neously after a few seconds. The episode, characterized by apnea during crying, cyanosis, SpO2 70%, bradycardia (37bpm) and loss of consciousness, recurred after 2h. Thepatient,withnosignsofairwayobstruction,received naloxone 0.4mg intravenously. However, the patient still

experienced two episodes with the same characteristics, always duringcryingspellsandafterapnea during expira-tion. The child wasthen sent tothe Intensive Care Unit, whereheremainedfor12h.Inthisperiodheshowedsome sporadicboutsofcryingaccompaniedbyadecreaseinSpO2. During the hospitalization,the echocardiogram and elec-trocardiogramwerenormal.Thechildwasdischargedwith a diagnosis of ‘‘shortness of breath’’ crisis. According to themother,sincethreemonthsofagethechildhadcrises characterizedby apneaduring crying,accompanied by lip cyanosis.Astheepisodeswereinfrequent,shedidnotseek medicalhelp.Oneweekaftersurgery,thechildexperienced another crisis characterized by pallor anddecreased pos-turaltone.

Discussion

This articledescribes thecase ofachild withahistory of ‘‘shortnessofbreath’’crisisundiagnosedbeforethe adeno-tonsillectomy,but thatrepresented thecause ofepisodes ofhypoxemiaandbradycardiainthepostoperativeperiod. The diagnosis of ‘‘shortness of breath’’crisis is basedon thereportofthreeor moreepisodescharacterizedbythe presence of atriggering factor such asanxiety,fear,pain orfrustration,followedbyweepingandapneainexpiration accompaniedbycyanosisorpallor.1,2_{The‘‘lossofbreath’’}

crisis can beconsidered as paroxysmal,non-epileptic and involuntary events thatmay occurduring childhood.1 _The

incidenceofchildrenwithahistoryof‘‘shortnessofbreath’’ crisis ranges from 0.1% to 4.6%.1 _{It has been shown that}

there is an autosomal dominant traitwith reduced pene-tranceinaconsiderableproportionofpatients.5_According

toDiMario,1_{inaprospectivestudyof95childrenwitha}

‘‘Lossofbreath’’asacauseofpostoperativehypoxiaandbradycardiainchildren 413

AccordingtoDiMariostudy,in5%ofchildrenthecrisesbegan whentheywerejustnewborns.

Inourcase,possibledifferentialdiagnoses,asthe resid-ual effectof opioids or edema in thesurgical field, were discardedbytheadministrationofnaloxone andbydirect visualizationofthelarynx.Althoughthefrequencyofcrises isdescribedasdailyorweekly,insomechildrentheinterval betweenepisodesmaybegreaterthanonemonth.Theboys seemtohaveamoreearlypeakfrequency(13---18months) comparedto girls (19---24 months).1 _{According toBridge,}6

whofollowed for nine years83 children witha historyof ‘‘shortness of breath’’ crisis, approximately half of them showedthelastepisodeatfouryearsofage.

The pathophysiology of the cyanotic variant of ‘‘shortness of breath’’ crisis probably has multiple factorsnotyetfullyknown.Theseincludehyperventilation (withconsequentexcessivereductioninPaCO2),apneaand decreasedvenousreturninducedbytheValsalvamaneuver.7

Loss of consciousness seems to be the result of changes in autonomic regulation, becauseit has been shown that thesechildrenhavetheocular-cardiacreflexexacerbated, which may be responsible for the asystole observed in 61%of casesof ‘‘shortnessof breath’’crisisaccompanied by pallor (also called cardioinhibitory syncope) and in 25%of thosecharacterizedby cyanosis.2,8 _{Althoughin our}

case the heart rate has reached values below 40bpm, bradycardia associated with ‘‘shortness of breath’’ crises hasbeenconsideredseverewhentheheartrateis<20bpm or asystole occursfor more than6s.2 _{Whensymptomatic,}

the bradycardia has been considered as an indication for pacemaker implantation.2 _{There is no specific treatment}

for‘‘shortnessofbreath’’crisis.Asanon-epilepticevent, there is no favorable response after administration of anticonvulsants.6 _{Thereis aneed toproperlyeducatethe}

parentsand,inthecaseofchildrenundergoinganesthesia, these authors believe that itsobservation in the hospital for at least 12h is important, because this is a periodin which countless possible triggering factors for the crises

areinvolved,andthereisnowaytopredictwhetherthere will be hemodynamic changes or loss of consciousness in thepossibleeventsthatwilloccurpostoperatively.

Toconclude,althoughconsideredbenign,the‘‘shortness ofbreath’’crisisshouldbeconsideredasapossiblecause ofperioperativehypoxiainchildren,especiallywhenthere isa suggestive history. Considering thatsome events may be accompanied by bradycardia, loss of consciousness, abnormalpostural tone andeven asystole, observation in ahospitalsettingshouldbeconsidered.

Conflicts

of

interest

Theauthorsdeclarenoconflictsofinterest.

References

1.DiMario Jr FJ. Prospective study of children with cyan-otic and pallid breath-holding spells. Pediatrics. 2001;107: 265---9.

2.KellyAM,PorterCJ,McGoonMD,EspinosaRE,OsbornMJ,Hayes DL.Breath-holdingspellsassociatedwithsignificantbradicardia: successfultreatmentwithpermanentpacemakerimplantation. Pediatrics.2001;108:698---702.

3.Hubbert CH. Post-operative apnoea caused bybreath-holding spells.CanAnaesthSocJ.1978;25:151---2.

4.Chhabra A, Baidya D. Postoperative cyanotic breath-holding spells in a child with Worster---Drought syndrome. J Anesth. 2010;24:982---3.

5.DiMario Jr FJ, Sarfarazi M. Family pedigree analysis of chil-dren with severe breath-holding spells. J Pediatr. 1997;130: 646---51.

6.BridgeEM, LivingstonS, TietzeC.Breath-holdingspells.Their relationship tosyncope, convulsions,and otherphenomena.J Pediatr.1943;23:539---61.

7.Menezes MAS. Paroxysmal non-epileptic events. J Pediatr. 2002;78Suppl.1:S73---88.