RevBrasAnestesiol.2017;67(1):85---88
REVISTA
BRASILEIRA
DE
ANESTESIOLOGIA
PublicaçãoOficialdaSociedadeBrasileiradeAnestesiologia www.sba.com.brCLINICAL
INFORMATION
Anesthesia
for
cesarean
section
in
a
patient
with
isolated
unilateral
absence
of
a
pulmonary
artery
Tomonori
Furuya,
Ryoji
Iida
∗,
Jyumpei
Konishi,
Jitsu
Kato,
Takahiro
Suzuki
NihonUniversitySchoolofMedicine,DepartmentofAnesthesiology,Tokyo,Japan
Received1June2014;accepted3July2014 Availableonline28October2014
KEYWORDS
Anesthesia;
Cesareansection;
Pregnancy;
Unilateralabsenceof
apulmonaryartery
Abstract
Backgroundandobjectives: Congenitalunilateralabsence ofapulmonaryartery(UAPA) isa rareanomaly.Althoughthereareseveralreportsregardingpregnancyinpatientswithunilateral absenceofapulmonaryartery,therearenocasereportsdescribinganesthesiafor Cesarean sectioninapatientwithunilateralabsenceofapulmonaryartery.
Casereport: Wepresentapatientwithunilateralabsenceofapulmonaryarterywho under-wentCesareansectionstwiceattheagesof24and26yearsunderspinalanesthesiaforsurgery andepiduralanalgesiaforpostoperativepainrelief.Bothtimes,spinalanesthesiaand epidu-ral analgesiaenabledsuccessfulanesthesia managementwithoutthedevelopmentofeither pulmonaryhypertensionorrightheartfailure.
Conclusion: Spinalanesthesiacombinedwithepiduralanalgesiaisausefulanestheticmethod foraCesareansectioninpatientswithunilateralabsenceofapulmonaryartery.
©2014SociedadeBrasileiradeAnestesiologia.Publishedby ElsevierEditoraLtda.Thisisan openaccessarticleundertheCCBY-NC-NDlicense( http://creativecommons.org/licenses/by-nc-nd/4.0/).
PALAVRAS-CHAVE
Anestesia; Cesariana; Gravidez;
Ausênciaunilateral
deumaartéria
pulmonar
Anestesiaparacesarianaempacientecomausênciaunilateralisoladadeartéria pulmonar
Resumo
Justificativaeobjetivos: A ausênciacongênitaunilateraldeumaartériapulmonar(ACAP)é umaanomaliarara.EmboraexistamváriosrelatossobrepacientesgrávidascomACAP,nãohá relatosdecasosdescrevendoanestesiaparacesarianaempacientescomACAP.
Relatodecaso: ApresentamosumapacientecomACAPquefoisubmetidaaduascesarianas, nasidadesde24e26anos,sobraquianestesiaparaacirurgiaeanalgesiaepiduralparaador nopós-operatório.Nasduascesarianas,araquianestesia eanalgesiaepiduralpossibilitaram
∗Correspondingauthor.
E-mail:ryoiida03@gmail.com(R.Iida).
http://dx.doi.org/10.1016/j.bjane.2014.07.002
86 T.Furuyaetal.
omanejobem-sucedidodaanestesia,semaocorrênciadequalquerhipertensãopulmonarou insuficiênciacardíacadireita.
Conclusão:Raquianestesiacombinadacomanalgesiaepiduraléummétodoanestésicoútilpara cesarianasempacientescomACAP.
©2014SociedadeBrasileiradeAnestesiologia.PublicadoporElsevierEditoraLtda.Este ´eum artigoOpen Accesssobumalicenc¸aCCBY-NC-ND( http://creativecommons.org/licenses/by-nc-nd/4.0/).
Introduction
Congenitalunilateralabsenceofapulmonaryartery(UAPA)
isarareanomalywithanestimatedprevalenceof
approx-imately1 in 200,000young adults.1 Patientswhohave no
cardiacanomaliesotherthanUAPAcanremain asymptom-aticevenintolateadulthood.Themostcommonsymptoms arerecurrentpulmonaryinfections,decreasedexercise tol-erance or mild dyspnea on exertion.2 The symptoms of
isolatedUAPAcanbeprovokedbypredisposingfactors,such as pregnancy3---8 or high altitude.2 Pregnancy is known to
increasecardiacoutput.Furthermore,unilateral lung per-fusionwiththeentirecardiacoutputisariskfactorforthe developmentofpulmonaryarterialhypertension.The prog-nosisofisolatedUAPAdependsonthepresenceorabsence ofpulmonaryarterialhypertension.2Althoughthereare
sev-eralreportsregardingpregnancyin patientswithUAPA,3---9
therearenocasereportsdescribinganesthesiafora Cesar-eansectioninapatientwithUAPA.Thus,thebestapproach toanesthesiaforCesareansectioninthesepatientsremains unclear. We present a patient who underwent Cesarean sectionsunder spinal anesthesia for surgery and epidural analgesiaforpostoperativepainrelieftwiceattheagesof 24and26years.
Case
report
Firstcesareansection
A 24-year-old woman, pregnant patient, with UAPA was admittedtoourhospitalat 35weeks’gestationfor deliv-eryandperinatalcare.ShewasdiagnosedwithUAPAatthe ageof15yearswhensheincurred right-sidedpneumonia. AchestX-rayrevealedtheabsenceoftherightpulmonary arterytrunk.Computedtomography revealedthe absence oftherightpulmonaryarteryandthepresenceofthree col-lateralvesselsfromtheascending aortatotheright lung. An echocardiogram did not image any additional cardiac anomalies. Right cardiac catheterization revealed normal pulmonary arterialpressure (PAP). At thetime of diagno-sis,shewasasymptomaticforUAPAandsurgicalcorrection wasnotindicated. She had nopast medicalhistory other thanUAPAandtheright-sidedpneumonia.
On admission, the patient wasasymptomatic. She had nopregnancy-relatedcomplications.Herheightwas154cm andherweightwas63kg.AchestX-rayshowedtheabsence of the right pulmonary artery trunk, mediastinal shift to the right and an expanded left pulmonary artery trunk
Figure1 Chestroentgenographyshowingabsenceoftheright pulmonary artery trunk,decreased pulmonary vasculaturein therightlung,shiftofthemediastinalstructurestotheright andanexpandedleftpulmonaryarterytrunk.
Anesthesiaforapatientwithunilateralabsenceofapulmonaryartery 87
via afacemask, an epiduralcatheterwasinserted at the Th12/L1 interspace. Next, spinal anesthesiawas adminis-tered at the L3/L4 interspace with 10mg of hyperbaric bupivacainehydrochloridehydrate.Fiveminutesafterthe injection, SAPwas 108/52mmHg, PAP was 6/2mmHg, HR was82beats/minandSpO2was99%.Fifteenminutesafter theinjection,thesensoryblocklevelwasbetweenTh1and S5. Atthis time,300mLof crystalloidfluidand 400mLof colloidal fluid had been administered intravenously. SAP, PAP andSpO2 did not change significantly. No cardiovas-cular agents were administered. Intraoperatively aswell, SAP,PAPandSpO2didnotchangesignificantly.Atdelivery, the neonate hadApgar scores of 8 and9 at 1 and 5min, respectively.Duringthedelivery,thePAPincreasedslightly from 10/7mmHg to 15/6mmHg while the SAP increased slightlyfrom100/50mmHgto108/65mmHg.Afterthe pla-centawasdelivered,10unitsofoxytocinwereadministered intravenously,which is routinepracticeatour institution. This administrationcaused a slight decrease in SAP from 108/65mmHgto100/55mmHgandnochangesinPAP. Mida-zolam wasadministered at a dose of 2mg asa sedative, whichresultedinnochangesinSAPorPAP.The administra-tionofasedativewasbasedonpatientdemand.Totalblood lossexcludingdilutionwithamnioticfluidwasapproximately 180mL.TotalfluidsadministeredunderPAPmonitoringand centralvenous pressure(CVP) monitoringincluded 400mL ofcrystalloidfluidand900mLofcolloidalfluid.Thepatient was pain-free throughout the operation. No cardiovascu-laragents wereadministered.The surgerywascompleted uneventfully.Postoperativepainwasadequatelycontrolled by epidural analgesia with 0.2% ropivacaine at a rate of 5mL/h, without supplementary analgesics. The high-est pulmonary systolicpressure reached was 20mmHg on thesecond postoperativeday. Postoperatively,theclinical coursesofthepatientandherinfantwereuneventful.
Secondcesareansection
Thepatientachievedasecondpregnancyatageof26years and was admitted toour hospital at 36 weeks’ gestation with nopregnancy-related complications. Her height was 154cmandherweightwas61kg. HerPAP waswithin nor-mallimits.ShewasscheduledtoundergoCesareansection at 37 weeks’ gestation under the same anesthetic plan as that of her first Cesarean section. On arrival to the OR, SAP was 115/76mmHg, PAP was 8/4mmHg, HR was 90beats/min and SpO2 was 97%. After application of all monitors asbefore and administration of 5L/min of oxy-gen viaafacemask, an epiduralcatheterwasinsertedat theTh12/L1interspace.Next,spinalanesthesiawas admin-istered at the L3/L4 interspace with 9mg of hyperbaric bupivacainehydrochloridehydrate.Fiveminutesafterthe injection,SAPwas115/52mmHg,PAPwas10/5mmHg,HR was92beats/minandSpO2was100%.Fifteenminutesafter theinjection,thesensoryblocklevelwasbetweenTh2and S5. Atthis time,300mLof crystalloidfluidand 300mLof colloidalfluidwereadministeredintravenously.SAP,PAPand SpO2didnotchangesignificantly.Therefore,no cardiovas-cular agents were administered. At delivery, the neonate had Apgar scores of 8and 9 at 1and 5min, respectively. During the delivery, the patient’s PAP increased slightly
from 11/4mmHg to 15/7mmHg. After the placenta was delivered,intravenous oxytocinat a dose of 10 units and intravenousmidazolamatadoseof2mgdidnotcauseany significantchangesinSAPorPAP.Totalbloodlossexcluding dilutionwithamnioticfluidwas190mL.Totalfluids admin-isteredunderPAPmonitoringandCVPmonitoringincluded 800mLofcrystalloidfluidand500mLofcolloidalfluid.No cardiovascularagents wereadministered.The patientwas pain-freethroughout the operation,which wasperformed uneventfully.Postoperativepainwasadequatelycontrolled withepiduralanalgesiawith0.2%ropivacaineat arateof 5mL/h,withoutsupplementaryanalgesics.Thehighest pul-monarysystolicpressurereachedwas22mmHg2hafterthe conclusionofsurgery.Thepostoperativeclinicalcoursesof thepatientandherinfantwereuneventful.
Discussion
Therehavebeennopreviouscasereportsdescribing anes-thesia for Cesarean section in patients with UAPA. We administered spinal anesthesia for surgery and epidural analgesiaforpostoperativepainrelieftoourpatientwith UAPA.Theadvantageofthisprotocolisthatitblocks intra-operativeandpostoperativenociceptivestimulicausedby surgery,thuspreventingthecardiovascularchangesinduced by these nociceptive stimuli. The disadvantage is that patients might need vasopressordrug administration or a significantlylargefluidinfusiontomaintainarterialpressure ifthelevelofspinalblockrises.Duringbothsurgeriesinour patient,spinalanesthesiacaused nosignificant cardiovas-cularorrespiratorychanges.Moreover,thepatientdidnot developanyseriouscomplicationsduringtheperioperative period.
SpinalanesthesiacausedsensoryblockadeuptoTh1for thefirstsurgeryandTh2forthesecondsurgery.The possi-blereasonswhythepatientdidnotrequireanyvasopressors includedproperfluidadministrationandthepatient’srobust circulation. A slow incremental epidural anesthesia com-bined with the lower-dose spinal anesthesiawas another anestheticoptionforthiscase.Thisoptioncouldhave reg-ulatedtheregionofsensoryblockade.
The PAP increased slightly on the second postopera-tive day for the first surgery and 2h postoperatively for the second surgery. It was probably due toongoing uter-inecontractionsafterdelivery.Uterinecontractionsinduce hypervolemia especially during the first few postpartum days.CloseobservationofthePAPisimportantduringthis period.Therefore,postoperativeanalgesiaisalsoimportant becausenociceptive sympathetic stimulation might cause rightheartoverload.
Administration of 10 units of oxytocin did not cause anysignificant cardiovascular changesduring both surger-ies; however, this dose is large for an elective Cesarean section.10 Adequate uterine contractions can usually be
achievedwithoxytocin at adose of <5units; this dosage can also minimize cardiovascular side effects.10---12
Oxy-tocinisproblematicparticularlyinpatientswithpulmonary hypertension becauseit raises the PAP.13 In addition, the
dropinsystemicvascularresistanceduetooxytocin.11 can
88 T.Furuyaetal.
obstetriciansandusedtheminimumdosenecessaryfor ade-quateuterinecontractionswhileconsideringtheamountof bloodloss.
AlthoughUAPAcanremainasymptomaticuntillate adult-hood,itcanbeunmaskedbypregnancy,3---8probablydueto
increasingcardiacpreloadduringpregnancy. Symptomsof UAPAcanalsobetriggeredbyspinalanesthesiaorCesarean section,becausetheseproceduresmightcauserightheart failureorpulmonaryhypertension.Rightheartfailureor pul-monaryhypertensionresultsfromexcessivecardiacpreload orafterloadduetoincreasedvenousreturnafterdelivery, excessivetransfusionorexcessivesympatheticstimulation duetonociceptivestimuli.Koga etal.reportedacase of awomaninwhomPAProseafterCesareansectionbecause ofa sudden increase in venous returnafter labor.3 Inour
patient, close cardiovascular and respiratory monitoring indicatedthatthesefactorswerenotsignificantlyalteredby eitherthespinalanesthesiaortheCesareansection.Spinal anesthesiaforsurgeryandpostoperativeepiduralanalgesia resultedincompletepainrelief.Thus,thisprotocolisa use-fulanestheticoptionforCesareansectioninpatientswith UAPA.
AreviewbyHarkeletal.,2reportedamortalityrateof
isolatedUAPA to be 7 (6.5%) of 108. The cause of death included pulmonary hemorrhage, right heart failure, pul-monaryhypertension,respiratoryfailureandhigh altitude pulmonary edema.2 Pregnancy is known to increase
car-diacoutput,whichcouldinducepulmonaryhypertensionin pregnantpatientswithUAPA,leadingtorightheartfailure orruptureofaffectedpulmonarycapillaries.Theliterature contains only seven previous reports addressing the clini-calcourseofpregnancyinpatientswithUAPA.3---9According
tothesestudies, UAPA wasunmasked by pregnancyin 10 patientswhopresentedwithsymptomssuchasdyspneaand chestpain.3---8Onepatientdevelopedadultrespiratory
dis-tresssyndromeonthesecondpostpartumdayanddied15 daysafterdelivery.6Therefore,patientswithUAPA
under-goingCesareansectionshouldbecloselyand continuously followed throughout the perioperative period, especially whenuterinecontractionsarepresent.
Conclusions
We administered spinal anesthesia for the Cesarean sec-tionandepiduralanalgesiaforpostoperativepainreliefin
a patient withUAPA in two instances. In both instances, neither pulmonary hypertension nor right heart failure developed. Thus, this combination is a useful anesthetic methodforCesareansectioninpatientswithUAPA.
Conflicts
of
interest
Theauthorsdeclarenoconflictsofinterest.
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