Differences in perioperative femoral and radial arterial blood pressure in neonates and infants undergoing cardiac surgery requiring cardiopulmonary bypass 夽

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www.jped.com.br

ORIGINAL ARTICLE

Differences in perioperative femoral and radial arterial blood pressure in neonates and infants undergoing cardiac surgery requiring cardiopulmonary bypass ^夽

Hwa Jin Cho

^a

, Sang Hoon Lee

^a

, In Seok Jeong

^b^,∗

, Nam Sik Yoon

^c

, Jae Sook Ma

^d

, Byoung Hee Ahn

^b

aChonnamNationalUniversityMedicalSchool,ChonnamNationalUniversityHospital,DepartmentofPediatrics,Gwangju, SouthKorea

bChonnamNationalUniversityMedicalSchool,ChonnamNationalUniversityHospital,DepartmentofThoracicand CardiovascularSurgery,Gwangju,SouthKorea

cChonnamNationalUniversityMedicalSchool,ChonnamNationalUniversityHospital,DepartmentofInternalMedicine, Gwangju,SouthKorea

dKSHospital,DepartmentofPediatrics,Gwangju,SouthKorea

Received26December2016;accepted20February2017 Availableonline30August2017

KEYWORDS Infant;

Neonate;

Congenitalheart disease;

Invasiveblood pressuremonitoring;

Femoralartery

Abstract

Objective: Severalreportsclaimthatbloodpressure(BP)intheradialarterymayunderesti- matetheaccurateBPincriticallyillpatients.Here,theauthorsevaluateddifferencesinmean bloodpressure(MBP)betweentheradialandfemoralarteryduringpediatriccardiacsurgeryto determinetheeffectivenessoffemoralarterialBPmonitoring.

Method: Themedicalrecordsofchildrenunder1yearofagewhounderwentopen-heartsurgery between2007and2013wereretrospectivelyreviewed.RadialandfemoralBPweremeasured simultaneously,andthedifferencesbetweenthesevalueswereanalyzedatvarioustimes:after catheterinsertion,aftertheinitiationofcardiopulmonarybypass(CPB-on),afteraorticcross clamping(ACC),afterthereleaseofACC,afterweaningfromCPB,atarrivalintheintensive careunit(ICU),andevery6hduringtheﬁrstdayintheICU.

Results: Atotalof121patientswhounderwentopen-heartsurgerymettheinclusioncriteria.

Duringtheintraoperativeperiod,fromthebeginningtotheendofCPB,radialMBPsweresignif- icantlylowerthanfemoralMBPsateachtime-pointmeasured(p<0.05).Multivariateanalysis

夽 Pleasecitethisarticleas:ChoHJ,LeeSH,JeongIS,YoonNS,MaJS,AhnBH.Differencesinperioperativefemoralandradialarterial bloodpressureinneonatesandinfantsundergoingcardiacsurgeryrequiringcardiopulmonarybypass.JPediatr(RioJ).2018;94:76---81.

∗Correspondingauthor.

E-mail:[email protected](I.S.Jeong).

https://doi.org/10.1016/j.jped.2017.03.011

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showed that longerCPB time(>60min, oddsratio: 7.47) was arisk factor for lower radial pressure.However, discrepanciesbetween thesetwovaluesdisappearedafterarrivalinthe ICU.Therewasnoincidenceofischemiccomplicationsassociatedwiththecatheterizationof botharteries.

Conclusion: Theauthorssuggestthatfemoralarterialpressuremonitoringcanbesafelyper- formed,eveninneonates,andprovidesmoreaccurateBPvaluesduringCPB-onperiods,and immediatelyafterweaningfromCPB,especiallywhenCPBtimewasgreaterthan60min.

4.0/).

PALABRASCLAVE Bebê;

Neonato;

Cardiopatia congênita;

Monitoramentoda pressãoarterial invasiva;

Artériafemoral

Diferenc¸asnapressãoarterialfemoraleradialnoperioperatórioemneonatos ebebêssubmetidosacirurgiacardíacacombypasscardiopulmonar

Resumo

Objetivo: Diversosrelatosalegamqueapressãoarterial(PA)naartériaradialpoderásubes- timaraPAprecisaem pacientesgravementedoentes.Aqui,avaliamosdiferenc¸asnapressão arterialmédia(PAM)entreaartériaradialefemoraldurantecirurgiacardíacapediátricapara determinaraeﬁcáciadomonitoramentodaPAdaartériafemoral.

Método: Realizamosumaanáliseretrospectivadeprontuáriosmédicosdecriançascommenos de1anodeidadesubmetidasacirurgiadecoraçãoabertoentre2007e2013.AsPAsradiale femoralforamauferidassimultaneamente,asdiferençasentreessesvaloresforamanalisadas diversasvezes:apósainserçãodocateter,apósoiníciodobypasscardiopulmonar(CPB-on), apóspinçamentocruzadoda aorta(ACC),apósaliberaçãodoACC, apósdesmamedoCPB, naentradanaunidadedeterapiaintensiva(UTI) eacada6horasduranteoprimeirodiana unidadedeterapiaintensiva(UTI).

Resultados: Umtotalde 121pacientessubmetidos acirurgia decoração aberto atenderam aosnossoscritériosde inclusão.Durante otransoperatório,doinícioaotérminodoCPB,as PAMsdaartériaradialforamsignificativamentemenoresdoqueasPAMsdaartériafemoralem cadapontodemedição(p<0,05).Aanálisemultivariadamostrouqueaduraçãomaislongado CPB(>60minutos,RazãodeChance=7,47)representouumfatorderiscodepressãoradial maisbaixa.Contudo,asdiferençasentreessesdoisvaloresdesapareceramapósaentradana UTI.Nãohouveincidênciadecomplicaçõesisquêmicasassociadasàcateterizaçãodeambasas artérias.

Conclusão: Sugerimosqueomonitoramentodapressãoarterialfemoralpodeserrealizadocom seguranc¸a,mesmoemneonatos,efornecevaloresdaPAmaisprecisosduranteperíodosdeCPB- oneimediatamenteapósodesmamedoCPB,principalmentenoscasosemqueadurac¸ãodo CPBfoisuperiora60minutos.

0/).

Introduction

Invasive blood pressure (BP) monitoring is essential for patients during and after open-heart surgery (OHS), and the radialarteryis themost common siteof catheteriza- tionduringOHS.However,manyinvestigatorshavereported that,inadults,duringtheearlyphaseof cardiopulmonary bypass(CPB),thefemoral arterialpressureis signiﬁcantly higherthantheperipheralarterialpressure.^1,2However,to thebestoftheauthors’knowledge,fewstudieshaveinves- tigatedthedifferencebetweenfemoralandradialarterial BPduringsurgeryandpostoperativeperiodinneonatesand infants.

Inthepresentstudy,thedifferencesinBPbetweenthe radial and femoral arteries in neonates and infants dur- ingtheperioperative periodwereevaluatedtodetermine whethertheywereclinicallyrelevant, andtoidentifythe patientgroupsinwhichthesedifferencesoccurred.

Materials and methods

This was a respective review of data, and the study was approved by the Institutional Review Board (CNUH-2015- 024). The authors retrospectively reviewed both surgical and medical data of patients under 1 year of age who hadundergone open-heartsurgery between January 2007 and December 2013. The exclusion criteria were as follows:OHSwithoutACC,CPBweaningfailure,conversionto extracorporealmembrane oxygenationsupport, earlyhos- pitalmortality(<24h),lackofsimultaneouscatheterization in the radial and femoral arteries, and congenital heart disease that could have affected the discrepancy in BP of these arteries, such as aortic arch anomalies. Demo- graphic data, including age at diagnosis, age at surgery, sex,weight,height,andbodysurfacearea,werereviewed.

Preoperative factors, such as cardiac diagnosis and med- ications were also reviewed in all patients. Among the

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intraoperativedata,thedurationofCPBandACCtimewas assessed.

Radialandfemoralarterialcatheterswereplacedafter inductionofanesthesia. Radialcannulationwasperformed witha24GJelco^® IVRadiopaqueCatheter(SmithMedical InternationalLtd.---Rossendala,UnitedKingdom).Femoral arterialcatheterizationwasperformedusingtheSeldinger techniquewitha22-Gand4.45-cmradiopaquecatheterin apediatricmulti-lumencentralvenouscatheterizationset withaBlueFlexTip^® catheter(TeleﬂexMedical---Plymouth, MN, USA). The arterial catheters were connected to two pressuretransducers(Transpac^®IVmonitoringkit;ICUMedi- cal--- SanClemente,CA,USA).Thepressuretransducerwas placedattheleveloftherightatrium.Systolicbloodpres- sure(SBP),diastolicbloodpressure(DBP),andMBPofeach arteryweremeasuredcontinuouslyandsimultaneously.All numberswererecordedin adigitalchartbyanesthesiolo- gistsevery5minintheoperatingroom(OR)andbyintensive care unit (ICU) nurses every 1h in the ICU. The detailed singledigitswereavailable.

BP values from both arteries were assessed at various times: preoperative (after catheter insertion following inductionofanesthesiaandpriortoskinincision),intraop- erative(afterthebeginningofCPB,afterACC,afterrelease of ACC, and after weaning from CPB), and postoperative period(every6h duringtheﬁrstdayintheICU).The MBP databetween the twoarteries werethen compared. The patients were divided into subgroups according to age (neonates and early infants less than 3 monthsand older infantsbetween3 and12months),accordingtoCPB time (<60min, 60---120min, >120min), and according to the vasoactiveinotropicscore (VIS)calculatedfromthemean VIS values within the ﬁrst 24h in ICU (<20, 20---40, >40).

Then, the differences between radial and femoral MBP were assessed in each subgroup. The VIS was calculated as follows: dopamine dose (mcg/kg/min)+dobutamine (mcg/kg/min)+100×epinephrine dose (mcg/kg/min)+ 10×milrinone dose (mcg/kg/min)+10,000×vasopressin dose (U/kg/min)+100×norepinephrine dose (mcg/kg/min).³

Thet-testforindependentsampleswasusedtocompare continuous variables between groups. Repeated measures analysis of variance (ANOVA) was used to compare the serialvaluesbetweenradialandfemoralarterialpressure during the operation and ICU stay. Odds ratios with 95%

conﬁdenceintervalswerecalculatedbylogisticregression analysisaccordingtotheriskoflowerbloodpressureinthe radial artery during CPB weaning period. In all analyses, p-values<0.05wereconsideredtoindicatestatisticalsignif- icance.ThestatisticalsoftwarepackageSPSS(IBMStatistics forWindows,Version 21.0,NY,USA) wasusedfor alldata analyses.

Results

Patientdemographicsduringpreoperativeperiod A total of 121 patients who underwent open-heart surgery fulﬁlled our inclusion criteria. The study popula- tion consisted of 50 patients (41.3%) under 3 months of age and 71 patients (58.7%) between 3 and 12 months.

Table1 Patients’characteristicsduringtheperioperative period(n=121patients).

Variable^a

Age 4.25±2.44

<3months 50(41.3)

3---12months 71(58.7)

Female 47(38.8)

Bodyweight(kg) 6.94±9.97

Height(cm) 59.06±6.91

Bodysurfacearea(m²) 0.29±0.06 Underlyingdisease

VSD 78(64.5)

TOF 14(11.6)

TAPVR 8(6.6)

TGA 7(5.8)

Others 14(11.5)

CPBtime 111.82±68.37

<60min 26(21.5)

60---120min 54(44.6)

>120min 41(33.9)

ACCtime 65.30±32.57

<60min 36(29.8)

60---120min 76(62.8)

>120min 9(7.4)

VIS^b 28.54±24.45

<20 69(57.0)

20---40 29(24.0)

>40 23(19.0)

ACC,aorticcrossclamp;CPB,cardiopulmonarybypass;TAPVR, total anomalous pulmonary venous return; TOF, tetralogy of Fallot; TGA, transposition of great arteries; VIS, vasoactive inotropicscore;VSD,ventricularseptaldefect.

a Dataarepresentedasthenumberofcases(%)forcategor- icalvariablesorasmeans±standarddeviationsforcontinuous variables.

b VISispresentedasmeanvalueswithintheﬁrst24hperiod intheICU.

Mean bodyweightwas6.94±9.97kg. Mean CPBtimewas 111.82±68.37min,meanACCtimewas65.30±32.57min, and mean VIS was 28.54±24.45 (Table 1). No signiﬁcant differenceswereobservedinBPbetweenthefemoraland radialarteriespriortotheinitiationofCPB(Fig.1).

Intraoperativepressuremonitoringbetweenthe radialandfemoralarteriesovertime

From the beginning to the end of CPB, radial MBPs were signiﬁcantly lower than femoral MBPs at each time-pint measured (p<0.05;Fig.1).Theauthorsalsoanalyzed the characteristicsofthepatientswhohadaradialMBPlower than10mmHgcomparedwiththe femoralMBPduringthe CPBweaningperiod;thisappliedto37patients(30.1%).Mul- tivariateanalysisrevealedthatalongerCPBtime(>60min) representedariskfactorforlowerradialpressure(Table2).

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a

b

d

c

PreOp CPB on ACC on ACC off CPB off ICU arrival Femoral MAP Radial MAP

Femoral MAP Radial MAP

Mean blood pressureMean blood pressure

A

B

100 90 80 70 60 50 40 30 20 10

76 74 72 70 68 68 64 62

1hr 6hr 12hr 18hr 24hr

Figure1 Changeofmeanbloodpressureintheradialandfemoralarteryaccordingtotime.(A)Comparisonofmeanbloodpressure duringtheintra-operativeperiod(a,b,c,d:p<0.05).(B)Comparisonofmeanbloodpressurewithintheﬁrstpost-operative24h.

ACC,aorticcrossclamp;CPB,cardiopulmonarybypass;ICU,intensivecareunit;MAP,meanarterialpressure;PreOp,preoperative.

Table2 Multivariateanalyses oflowerbloodpressurein theradialarteryduringtheCPBweaningperiod.

Variable PG(mFAP---mRAP)>10mmHg Oddsratio 95%CI p-Value ACCtime>60min 0.40 0.17---0.87 0.02 CPBtime>60min 7.47 2.89---19.27 0.01 Age<3months 0.64 0.25---1.58 0.33 VIS>20duringCBP

weaning

1.01 0.97---1.03 0.71

ACC, aortic crossclamp; CI, conﬁdential interval; CPB, cardiopulmonarybypass;FAP,femoralarterialpressure;m,mean;

PG,pressuregradient;RAP,radialarterialpressure;VIS,vasoactiveinotropicscore.

Postoperativepressuremonitoringbetweenthe radialandfemoralarteriesovertime

Duringthepostoperativeperiod,nosigniﬁcant differences in MBP wereobserved between the two arteries(Fig. 1).

Evenwhenpatientsweredividedintosubgroupsaccording toage,CPBtime,andVIS,theanalysisshowednosigniﬁcant differencesbetween theradialand femoralMAP for each subgroup(Table3).

Safetyofradialarteryandfemoralartery catheterizationandrelatedcomplications

Theformationofsmall(<2cm)hematomasoccurredinthree patientsand local infection wasobserved in one patient.

Therewerenocasesofperfusion-relatedlimbischemiain eitherofthearteries.

Discussion

Many investigators have reported the safety of femoral arterialcatheterizationduringadultcardiacsurgery^4,5;however, studies on the characteristics of femoral arterial pressure monitoring in neonates and infants are few. In the present study, the authors examined the differences betweenfemoralandradialbloodpressureinneonatesand

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Table3 Comparisonofradialandfemoralarterialpressurewithintheﬁrst24hpostoperative.

Variable Subtype 1h 6h 12h 18h 24h p-Value

Age

<3month mRAP 67.47±14.12 56.28±19.54 62.18±11.45 63.61±16.40 65.85±10.58 mFAP 66.00±13.88 60.59±10.72 61.85±11.08 62.17±19.02 63.22±16.81 0.64

≥3month mRAP 74.10±12.25 64.89±18.43 69.18±7.98 72.14±17.75 69.36±20.72 mFAP 74.69±12.79 67.39±9.79 67.96±8.97 71.71±19.50 71.22±16.57 0.97

CPBtime

<60min mRAP 80.15±11.10 72.83±10.03 73.05±6.82 78.26±19.19 75.00±18.42 mFAP 79.77±12.38 70.08±9.27 71.15±7.00 78.85±10.68 75.96±9.83 0.33 60---120min mRAP 72.28±11.76 66.37±8.43 67.04±8.02 71.16±14.91 69.77±17.47

mFAP 72.37±11.67 66.43±8.29 66.66±8.21 69.86±17.64 69.37±16.96 0.91

>120min mRAP 63.67±12.98 58.49±12.46 60.44±11.53 59.15±15.58 60.98±13.68 mFAP 63.82±13.93 58.63±11.68 60.00±12.05 56.34±22.24 59.76±18.07 0.95

VIS

<20 mRAP 76.32±11.84 65.89±16.87 69.45±7.79 74.09±15.52 70.97±18.83 mFAP 76.19±12.32 67.64±9.15 68.47±8.45 71.94±19.38 71.05±15.79 0.68 20---40 mRAP 68.60±11.60 57.56±21.64 64.14±7.74 65.70±16.16 65.40±16.27 mFAP 67.97±13.16 63.34±8.62 63.21±8.07 63.07±21.04 63.49±21.17 0.65

>40 mRAP 58.21±10.85 52.43±19.69 58.92±14.42 55.86±18.61 61.90±11.13 mFAP 59.19±11.06 56.82±13.41 58.52±14.30 58.87±15.25 63.02±12.82 0.93

CPB,cardiopulmonarybypass;FAP,femoralarterialpressure;m,mean;RAP,systolicradialarterialpressure;s,systolic;VIS,vasoactive inotropicscore.

infantsandobservedthatradialarterialpressurewasusually underestimated ascompared tofemoral arterial pressure duringtheCPB-onperiodinthispopulation.However,this phenomenondidnotextendintotheICUperiod.

In general, as the arterial pressure waveform moves toward the peripheral artery, the systolic pressure grad- uallyincreases and thesystolic portionof the waveforms becomesnarrower.Diastolicpressureusuallydecreasesand meanpressureremainsunchangedordecreasesminimally.⁶ However, this phenomenon is inﬂuenced by the clinical conditionofthepatient,includingthepresenceofperiph- eralvasculardisease,theuseofvasoactiveagents,andbody temperature.^7---9

Cardiac surgery withCPB is the most important factor affecting discrepancies in intra-arterial pressure between central and peripheral arteries, and several studies have reported such ﬁndings during and after adult cardiac surgery;thishasbecomeanestablishedpathophysiological featureof adultcardiac surgery.^1,2 Vasomotor dysfunction aftercardiacsurgerywithCPBresultsinreducedperipheral vascularresistance,whichclinicallymanifestsasanunder- estimationofBPintheperipheralarteries.Thisphenomenon occurs secondary to abnormal vascular permeability and tissueedema, which can contribute todysfunctionin the heart,lung,brain,kidneys,andotherorgans.^10,11Therefore, althoughtheperipheralarterialpressure,suchasthatinthe radialartery,is morecommonly monitored duringcardiac surgery,ittendstobeunderestimatedanditsreliabilityhas beencalledintoquestion.

Reduced radial arterial pressure can be caused by vasospasmasa resultof certainthermoregulatorymecha- nisms;similarly, femoraltoradialpressuregradientshave been observed in patients with hypothermic circulatory arrestorincriticallyillsurgicalpatientstreatedwithhigh dosesofvasoactive agents.^9,12,13 Chauhanetal.¹ reported thatFAPmonitoringwasmorereliableduringtheinitialpart ofCPBin60patientsofallages(range:3---65years)undergoing cardiac surgery. These authors found that femoral

arterial pressure was higher than radial arterial pressure duringCPB,especiallyduringtheinitiationofCPB;however, the differences between the radial and femoral arterial pressurewerelowerafter60minofCPB.Theirstudypop- ulation consistedof 60 patients,and included awide age range;thisrepresentedamajordifferencewhencompared tothepresentstudy,whichfocusedonlyonpatientsyounger than1yearsofageandfoundthatfemoralarterialpressure washigherat the initiationofCPB andimmediately after ACCreleaseinallneonatesandinfants.

In the present study, the location of the distal tip of thefemoralcatheterwasnotconﬁrmed.Nonetheless,the length of catheter for the femoral artery was 4.45cm;

therefore,it canbeassumedthatinsmaller patients,the distal tip would be located in the descending aorta, and in largerpatients, it might be located in the descending aortaor inthebifurcation ofiliac arteries.Whilefemoral arterial pressure represents central aortic pressure more accurately,therehavebeensomereportsofcomplications causedbyfemoralarterialcatheterization.Severalstudies have indicated a complication rate of 2.4---25.0% associ- atedwithfemoralarterialcatheterizationinneonatesand infants. Dumond et al.¹³ reported that the incidence of pedal pulse loss, distal to the catheter, in neonates and infants, wasrelated tothe sizeofthe catheteranddura- tion of use. Longer duration or larger size was directly related to perfusion-related complications from femoral arterial catheterization. In the present study, only tran- sientandminorcomplicationswereobserved,suchassmall hematomas and local erythema; no major complications such as limb ischemia associated with femoral arterial cannulation were observed. However, further prospective studies using serial ultrasonography are now needed to fullydeterminethesafetyoffemoralarterialcannulation.

Moreover, aseptic maneuvers should be performed by an experiencedphysician,anditisessentialtocarefullymon- itor theinsertion site andlimb color distal tothe site of catheterization.

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Thisstudywaslimitedbyitsretrospectivestudydesign, and by the fact that this was a single institutional study withasmallsamplesizeinpatientswithavarietyofcon- genitalheartdiseases.IntheICU,BPwasmeasuredhourly, which does not always represent the pattern of BP during the entire hour. Furthermore, noobjective diagnostic methodsuchasultrasoundwasusedtoassesscomplications.

Intheauthors’experience,thenumberofbothradialand femoralattemptsincreasesinsickerandsmallerchildren.

Itcouldthereforebetheorizedthattheincreasednumber of radial attempts in sicker (longer bypass) and younger children could traumatize the artery and thus contribute tothelowerreadingsobtained.Furtherstudiesareneeded toinvestigatethenumberofcannulationattemptsandthe associatedpressuredifferences.

Theauthorsconcludethat,inourthisstudypopulation, radial arterial pressure was usually underestimated com- paredtofemoralarterialpressureaftertheinitiationofCPB, andthatthedifferencesbetweenradialandfemoralarte- rialpressureweremoremarkedinpatientswithlongerCPB time.Itwasalsoobservedthatthesepressuredifferences werenotapparentduringtheICUperiod.

Funding

Thisstudywassupportedbyagrant(CRI11083-33)fromthe ChonnamNationalUniversityHospitalBiomedicalResearch Instituteandbyagrant(NRF-2016R1D1A1A02937493,NRF- 2015R1C1A1A02037778 and NRF-2016R1D1A3B03935986) throughtheMinistryofEducationoftheRepublicofKorea andNationalResearchFoundationofKorea.

Conﬂicts of interest

Theauthorsdeclarenoconﬂictsofinterest.

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