Andersons pediatric cardiology 2261
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RespiratoryInfections.
Lowerrespiratoryinfectionsarenowidentifiedasthesinglemostimportant
causeofdeathinallchildrenbeyondtheneonatalperiodinLMICs.57Infants
andchildrenwithCHDandincreasedpulmonarybloodflowareespecially
vulnerabletosevereandseeminglyrefractorypneumonia.Heartdiseaseisoften
identifiedforthefirsttimeduringtheseepisodes.
Thescenarioofachildwithalargeleft-to-rightshunt,typicallyalargeVSD
andseverepneumoniasometimesnecessitatingmechanicalventilation,isa
commononeintheLMICenvironment(Fig.88.5).55Thesebabiesneedtobe
“stabilized”priortosurgery.Therearefewstudiesthatindicatepossible
strategies,butnoclearguidelinesexistabouttimingofsurgery.Asaresultthere
iswidevariationinpracticesamonginstitutions.Itisoftennotpossibleto
accomplishtheidealgoalofcompleteresolutionoftheinfectionpriortosurgery.
Indeed,amongthemostseverelyaffectedchildrenwhorequiremechanical
ventilation,itisoftennotpossibletoextubatethempriortosurgery.58In
addition,atransientincreaseinPVRresultingfromlunginfectionandimpaired
gasexchangemightresultinright-to-leftshunting,whichcreatesuncertaintyin
determiningtheoptimaltimingofsurgicalintervention.Apragmaticstrategyof
operatingafterpartialcontroloftheinfectionasevidencedbyabsenceoffever
for48hoursormore,decliningwhitecellcountifinitiallyelevatedand
improvingplateletcountifinitiallyreduced,someresolutionofchestsigns,
improvinggasexchange,andpartialradiologicclearanceoflunginfiltrateshas
beenadoptedbyselectedinstitutions.58Althoughpostoperativerecoveryisoften
prolongedincomparisonwithchildrenwhoarenotinfected,impressivesurgical
outcomeshavebeenreported.Mostunitsprefertoclosetheshunt(e.g.,alarge
VSD)ratherthanpalliatewithapulmonaryarterybandduetobetteroutcomes
followingdefinitivesurgery.Babieswithalargepatentarterialductand
pneumoniacanundergocatheterclosureafterpartialcontrolofactiverespiratory
infections.Thisoftenallowsrapidrecovery.59
FIG.88.5 Typicalchestradiographofaninfantwithalargeventricular
septaldefectandseverelunginfectionnecessitatingmechanical
ventilation.Notetheenlargecardiacsilhouette.
Thisstrategymaynotworkincomplexlesionswithincreasedpulmonary
bloodflow,suchascorrectedtranspositionwithVSDs,wherelong
cardiopulmonarybypasstimesareanticipated.Inaddition,itisquitechallenging
toundertakeapulmonaryarterybandaspalliationforpatientswitheithera
functionallyuniventricularheartorcomplexCHDthatareeventualtwoventriclecandidatesinthepresenceofactivelunginfections.Thisisbecauseof
eitherbaselinesystemichypoxemiaand/orlabilePVRthatmakesitrather
difficulttoaccuratelysizethebandoradequatelyprotectthepulmonary
vasculature.
BloodstreamSepsisinNeonates.
InfectionsareamajorcauseofneonataldeathinLMICs.Globally,ofthe
estimated6.3milliondeathsinchildrenyoungerthan5yearsin2013,2.8
million(44%)deathswereintheneonatalperiod(0to27days),and0.42(95%
CI,0.27to0.69)millionofneonataldeathswereduetosepsis.Theestimateof
possibleseverebacterialinfectioninneonatesinSouthAsia,Sub-Saharan
Africa,andLatinAmericain2012was6.9(95%CI,5.5to8.3)million.60
Hospital-bornbabiesindevelopingcountriesareatincreasedriskofneonatal
infectionsbecauseofpoorintrapartumandpostnatalinfection-controlpractices.
Reportedratesofneonatalinfectionswere3to20timeshigherthanthose
reportedforhospital-bornbabiesinindustrializedcountries.Gram-negative
organismspredominate,andmultidrugresistanceiscommon.61Childrenwith
heartdiseasetypicallyspendvariableperiodsoftimeindifferenthospitalsand
arelikelytobehandledbyanumberofhealthcareworkers.Thisfurther
increasesthelikelihoodofsepsiswithmultidrugresistancestrains.Preoperative
sepsisisstronglyassociatedwithpostoperativebloodstreamsepsisandhasa
majorimpactonpostoperativemortalityandmorbidity.26
ThespecificchallengesrelatingtooperatingonnewbornswithCHDand
sepsisrelatestotimingofsurgery.Itisnotoftenpossibletoadminister
antibioticsforthestipulateddurationpriortosurgerybecausethechild's
conditionmaynotallowsubstantialdelayinsurgery.Agoodexampleisa
newbornwithobstructedtotalanomalouspulmonaryvenousreturn.
Inmanysituations,forexampleapatientwithlatepresentationofdtranspositionofthegreatarterieswithconcurrentgram-negativeorfungalsepsis
mayhavetobeadequatelytreatedpriortosurgery,causingfurtherdelaysin
surgery.Innovativetemporizingproceduressuchasstentingofthearterialduct
withanatrialseptostomymayneedtobedonetooffsetthedelayinsurgery
incurredduetocoexistentsepsis.
PostoperativeInfections.
PostoperativeinfectionsarecommonerintheLMICsettingswhencompared
withdevelopednationspresumablybecauseoflimitationsininfectioncontrol
practices.InastudyfromtheIQICinvolving14,545pediatriccardiacsurgical
casesfrom27participatingsitesin16LMICs,theincidenceofbacterialsepsis
was5.5%andsurgicalsiteinfectionswas2.1%.62Youngerageatsurgery,higher
surgicalcomplexity,loweroxygensaturation,andmajormedicalillnesswere
independentriskfactorsforinfection.
In-hospitalmortalitywasnearlythreetimeshigheramongcaseswithinfection
thanamongthosewithoutinfection(16.7%vs.5.3%;P<.001),aswere
postoperativeventilationduration(80vs.14hours;P<.001)andintensivecare
unitstay(216vs.68hours;P<.001).TheIQICalsoimplementedtargeted
educationalprogramsforinfectioncontrolduringtheperiodofdatacollection
andtheinfectionratesdeclinedsignificantlybyabout50%overthe2-year
period.62Simpleinfectioncontrolpracticescanbeimplementedatlowcostsin
