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PerioperativeUpperAirwayConsiderationsinPediatricObstructiveSleepApnea

KimmoMurto MD,FRCPC

DepartmentofAnesthesiology&PainMedicine,CHEOAssociateProfessor,UniversityofOttawa,FacultyofMedicine

Email:Kmurto@cheo.on.cawww.sasmhq.org

ConflictofInterest

• Nonetodeclare

OBJECTIVESAttheendofthissessionaudiencememberswillbeableto:

• UnderstandhowOSArelatedupperairwaystructure,functionandrelatedpathophysiologyimpactanestheticmanagementinchildren.

• ListkeylimitationsofpublishedpediatricOSAassociatedmanagementguidelines.

• Appreciatearoleforanti-inflammatoryagentstomodulate perioperativerespiratoryadverseevents(PRAEs)inchildrenwithOSA.

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PerioperativeCare&Anesthesiology

PreoperativeOptimization

PostoperativeRecovery:DaycareorIn-patient

LAI=LocalAnestheticInfiltration;PNB=peripheralnerveBlock

Sedation&LAI

RegionalAnesthesia:NeuroaxialorPNB

Ketamine GeneralAnesthesia

&LAI

General&Regional

Anesthesia

IntraoperativeCare:Anxiolysis

UnconsciousAmnesiaAnalgesia

MuscleRelaxation“OSA:RiskStratification&Diagnosis” “Monitoring”&

“Analgesia”

AnxiolysisUnconsciousAnalgesia

MuscleRelaxation

Murto K.Anesth Analg 2018

ObstructiveSleepDisorderedBreathing(SDB)

• “Asyndromeofupperairwaydysfunctionduringsleepcharacterizedbysnoringand/orincreasedrespiratoryeffortthatresultfromincreasedupperairwayresistanceandpharyngealcollapsibility”

Kaditis AGEur Respir J2016

SDBSpectrum

Normal PrimarySnoring

UpperA/WResistanceSyndrome(UARS)

ObstructiveHypoventilation

(OH)

ObstructiveSleepApnea(OSA)

NormalUAR,nosnoring

Habitualsnoring,no

abnormalities

↑workofbreathing,arousals,

cognitive/behaviorsymptoms

noobviousobstructiveevents,but↑ExpCO2

Partial/totalobstructive

events,arousals,AbnO2/CO2,

end-organeffects

PediatricOSAPrototype=Adenotonsillar hyperplasia

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PediatricOSAS&SocietalImpact

• Common• 1-5%ofchildren;↑ with obesity• ?Surgicalprevalence• M>F&agephenotypes• Secondary&associatedmorbidity

• ↓ socioeconomicstatus• Expensive• ↓Schoolandjobperformance• ↑healthcareutilization• AlteredCVShealthtrajectory

• Shorterlifespan• Treatment&healthtrajectory

Jennum Petal.Thorax 2013

Pediatricmortalityafteradenotonsillectomy

Source Years 15-30DayDeathRate(per10,000)

Adenotonsillectomy

US(BrownKAnesth Analg 2014) 1970s 0.3-0.6

USout-patient(ShaySLaryngoscope2015) 2010 0.6

USin-patient(Allareddy VClin Pediatr 2016) 2001-10 4

Canadain/out-patient(MurtoKCanJAnesth 2017) 2002-13 0.2

Swedenin/out-patient(Østvoll EEur ArchOtorhinolaryngol 2015) 2004-11 0.24PediatricPredictionToolsforPerioperativeMorbidity&Mortality:

“PulmonaryorRespiratoryDisease”(SubramanyamRAnesth Analg 2015;NasrVGAnesth Analg 2017)

TheElephantintheRoom:LethalApneaatHomeafterATBrownKAnesth Analg June2014

Laryngoscope2013

Pediatr Anesth 2014

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OSAassociatedwithincreasedrespiratorycomplications&dose-responseevident

Pediatrics 2015

OSASyndromeOxidativeStress+ ↑Pco2InflammatoryCascadeAutonomicDysfunctionFrequentMicro-arousals

Environment

CardiovascularMorbidity MetabolicMorbidity Neuro-cognitive&BehaviorMorbidity

↑BP&LVStrain

EndothelialDisruption

AssociatedObesity→Insulin

Resistance

Athero-ScleroticLipidProfile

↓Memory,IQ&ExecutiveFunction

Hyperactive,Impulsive,↓Attention&Concentrat’n

GeneticPredisposition

End-OrganDysfunction

↑BP&LVStrain

AssociatedObesity→Insulin

Resistance

AbnormalLipidProfile

MetabolicSyndrome

RespiratoryMorbidity(Asthma&URTI)

GutierrezMJ.Pediatri Pulmonl 2013Bhattacharjee R.PLoS Med2014

TanHLNatSci Sleep2013

?GIMorbidity(GERD)

Polysomnography(PSG)isdiagnostic“GoldStandard”

“DIAGNOSTIC”SEVERITYisbasedonthefollowing:• PSGdata-Apnea-hypopneaindex(AHI)andgasexchange.• Nocturnalanddaytimesymptoms• Age• Secondarycomorbidities• Associatedcomorbidities

• Interpretedbyasleepmedicinespecialist• Limitedaccessandexpensive

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Pediatricmanagementguidelinesareconfusing…

• ASAPracticeguidelinefortheperioperativemanagementofpatientswithobstructivesleepapnea2014• AAP Diagnosisandmanagementofchildhoodobstructivesleepapneasyndrome2012• AAOHNS FoundationClinicalpracticeguideline:Tonsillectomyinchildren2011• AAOHNSFoundationClinicalpracticeguideline:polysomnographyforsleep-disorderedbreathingpriortotonsillectomyinchildren2011• AASM Executivesummaryofrespiratoryindicationsforpolysomnographyinchildren:anevidencebasedreview2011

PSGIndications“Everyone”--------------------Prescriptive-----------Notreallynecessary

AHIDiagnosticThresholdfor“Severe”OSA=↑RiskforPRAE?Yes------------No----Whatdoes“severe”mean?----Notacknowledged

PSGAlternativesAcceptable?Yes----------------------------------No----------------Notacknowledged

OSASdiagnosisismovingoutofthesleeplab

Questionnaires• Symptomsnotdiagnostic

• Physicalfindings“unreliable”

• Researchbasedimpractical

• STBURand“ShortScale”

• Nopediatric“STOPBANG”

• Includeassociatedco-morbidities(defineendotype)

Otheroptions• Single-channelrecordings

• Oximetry+ airfloworECG

• Home-basedsleepstudies• PSGandpolygraphy

• BiologicalMarkers(DeLucaCantoGSleepMedRev2015)• Blood• Urinary-mostpromising• Salivary• Exhaledcondensate

GozalDCurr Opin Pulm Med2015

“RelevantAsthmaEndotype?”

“Typical”tonsillectomydispositionplanning

SchwengelDAAnesthesiologyClin 2014

Definition“Severe”OSAleadingto↑riskofPRAE:NOCONSENSUS

UnknownhowPRAEriskmodulatedbyassociatedpathophysiology,age,comorbidities,skillofproviders(andopioids)

Intensivecareunitadmissioncriteria:NOCONSENSUS

Monitoraccordingtolocalpractice

DoesriskforPRAEvarybyprocedure?

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OSAage-relatedairwayphenotypes

PediatricOSAEndotypes Infant(0-<2yrs)

Child(2-8yrs)

Pre-teen/Teen(9-21yrs)

Lymphoidhyperplasia(adenoids+/- tonsils) +/- +++ +Softtissue

Obesity +/- ++ +++“Genetic”(e.g.Hurler’s,Prader-Willi,Beckwith-Wiedemann)

++ +++ +

CraniofacialSyndromesVault&Mandible(e.g.Craniosynostosis&PRobin)

+++ ++ +/-

ForamenMagnum(e.g.Arnold-Chiarii) ++ ++ +/-Neuromuscular(e.g.Cpalsy&Trisomy21) + +++ ++Prematurity(<32wks) +++ + -Inflammatory(e.g.Asthma&SickleCellDis.) +/- +++ ++

SchwengelDAAnesthesiologyClin 2014

NasopharyngealAirway

Retroglossal Airway

Genioglossusmuscle

PROMOTEA/WCOLLAPSE

Negativepressureoninspiration

Extra-lumenPositivepressure:FatdepositionSmallmandible

Genioglossuscontraction

Lungvolume(longitudinaltrachealtraction)

PROMOTEA/WPATENCY

FactorscontributingtoairwaypatencyandcollapseinpediatricOSA

Rigid“Box”

ACollapsibleTube

SoftTissue

PlumenPTissue

Relationshipbetweenairflow&resistance

Q=ΔP/R Rɑ1/radius4

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Pharyngealwalltension,trachealtraction&abdominalpannus

Doesdysfunctionalneuro-motorcontroloftheupperairwayhavearole?

• Dayvsnighttimeobstruction• ↑EMGgenioglossusactivity• NotallchildrenwithanatomicalobstructionhaveOSA• VariableOSAcureratefollowingadenotonsillectomy

PathophysiologyofpediatricOSA:StructurallabmodelIsonoS.EncyclopediaSleep2013

TransmuralPressure=Plumen-Ptissue(cmH2O)

0 20-5

(cm2)5

Pediatric

-15

Cross-SectionofRigidBox&CollapsibleTube

Non-OSA=Pclose <0cmH20 OSA=Pclose >0cmH20

OSA

Adult

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OSAandupperairwayneuromotor control

UpperAirwayFindings Receptor(Location)

OSAPhenotypesInfant

(0-<2yrs)Child

(2-8yrs)Pre-teen/Teen(9-21yrs)

Collapsibility(genioglossus) CO2(BrainStem)

Mechano (airway)High High High

Ventilatory drive O2(Peripheral)CO2(BrainStem) ? Normal ?

Arousibility“AirwaySelf-Rescue”

O2(Peripheral)CO2(BrainStem)Mechano (airway)

Blunted Blunted Bluntedtohigh

VentilatoryControlinstability-“LoopGain”

O2(Peripheral)CO2(Peripheral&BrainStem)

?High ?High ?High

Arens R&MarcusC.Sleep 2004

O2administrationimprovesventilatory controlinstability

Upperairwaycollapsibility:Anestheticagents&opioids

GenericDrugName

AirwayCollapse

MechanismofAction

Midazolam + CNSGABAA,?α doseSevoflurane +++ CNSGABAA,α doseDesflurane +++ CNSGABAA

Propofol ++ CNSGABAA/NMDA,α doseDexmedetomidine +/- CNSα2 adrenergicagonistKetamine +/- NMDAreceptorantagonist;↑EMGgenioglossus(rats)TopicalLidocaine + ↓Dilator/tensormusclespharynx/larynxOpioids ++ ↓ventilatory &pharyngealneuromotor drive

EhsanZLaryngoscope 2016

GABAA receptors-stimulationleadstomyo-relaxation

Anestheticagentsenhance GABAA receptoractivityCampagnaJANEJMMay2003

GABAA receptoractivityaugmentedbyanestheticagentsinpresenceofIL-1

CellReports2,September2012

Anesth Analg April2012

PreventionofPRAEsinOSApatients:IstherearoleforsteroidsorNSAIDs?

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Perioperativesteroidadministrationimprovingadenotonsillectomyoutcomes

NEng JMed2013

CaulfieldHMClin Otolaryngol 2012

Oxidativestress&sensitivitytoopiatesinpediatricOSAS

Anesth Analg 2010

Anesthesiology 2006

Anesthesiology 2006

Pediatr Anesth 2010;20:1078-83

Musclerelaxants,reversalagents&theupperairway

Anesthesiology 2014

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Summary:PerioperativeUpperAirwayConsiderationsinChildrenwithOSA

• PATIENT• Pronetoimpairedairwayneuro-motorfunctionduetodrugs• SpectrumofcomorbiditiessecondarytoOSAor“age-specific”

• PREOPERATIVE• RiskStratificationforPRAE

• Age<3yrs&“significant”comorbidities• “Severe”OSAbyHx/Px,PSGorOvernightPulseOximetry• “PrescriptivePSG”needed?• “Invasiveness”ofsurgery&anesthesia• Needforpostoperativeopioids

• POSITION• Headup“TrachealTethering”,avoidbeingsupine

Summarycontinued

• PROCEDURE• Goals-preparefor“challenging”airway&PRAEs• Noone“best”anesthetictechnique;• “Pharyngealsparing”approach• Emergeawakeandconsidernasopharyngealairway

• POSTOPERATIVE• Monitoring

• ContinuousSpO2preferablyonroomairandasleep• Appropriatedurationunknown(2-6hrs)• Significanceofminor/majorPRAEsduringrecoveryunknown

(WeingartenGAnesth Analg 2015)• Analgesia

• Multimodalandavoidopioidinfusionsor“around-the-clock“• Optimalapproachunknown(AndersonBJPediatr Anesth 2011)

• ParentPreparation• 2019AAOHNSTonsillectomyGuideline

KimmoMurtoMD,FRCPC

DepartmentofAnesthesiology&PainMedicine,CHEOAssociateProfessor,UniversityofOttawa,FacultyofMedicine

Email:Kmurto@cheo.on.cawww.sasmhq.org

Thankyou!