Rev. Bras. Anestesiol. vol.66 número5

RevBrasAnestesiol.2016;66(5):549---550

REVISTA

BRASILEIRA

DE

ANESTESIOLOGIA

CLINICAL

INFORMATION

Simple

handling

of

venous

air

embolism

during

abdominal

myomectomy

Betül

Basaran

,

Ahmet

Basaran

,

Betül

Kozanhan

,

Sadık

Özmen

,

Mustafa

Basaran

a_{DepartmentofAnesthesiologyandCriticalCare,KonyaEducationandResearchHospital,Konya,Turkey} b_{DepartmentofObstetricsandGynecology,KonyaEducationandResearchHospital,Konya,Turkey}

Received28January2014;accepted5February2014 Availableonline7June2014

KEYWORDS

Venousairembolism; Myomectomy; Anesthesia

Abstract Wereportacaseofvenousairembolismduringabdominalmyomectomy.Although trueincidenceofvenousairembolismisnotknown,inliteraturemostofreportedcasesare belongstosittingpositioncraniotomies.Manyofthosearesubclinical,anddiagnosticmethods have varying degrees ofsensitivity andspecificity. Attime of suspicion, prevention ofany subsequentairemboliisthecornerstoneoftreatment.

©2014SociedadeBrasileiradeAnestesiologia.Publishedby ElsevierEditoraLtda.Thisisan openaccessarticleundertheCCBY-NC-NDlicense( http://creativecommons.org/licenses/by-nc-nd/4.0/).

PALAVRAS-CHAVE

Emboliaaérea; Miomectomia; Anestesia

Manejosimplesdeemboliagasosadurantemiomectomiaabdominal

Resumo Relatamosumcasodeemboliagasosadurantemiomectomiaabdominal.Emboraa incidênciaexatadeemboliagasosanãosejaconhecida,amaioriadoscasosrelatadosna liter-aturaserefereàposic¸ãosentadaemcraniotomias.Muitoscasossãosubclínicoseosmétodos diagnósticostêmdiferentesgrausdesensibilidadeeespecificidade.Nomomentodasuspeita, aprevenc¸ãodequalquerêmbolodearsubsequenteéachavefundamentaldotratamento. ©2014SociedadeBrasileiradeAnestesiologia.PublicadoporElsevierEditoraLtda.Este ´eum artigo OpenAccess sobumalicenc¸aCCBY-NC-ND( http://creativecommons.org/licenses/by-nc-nd/4.0/).

A36-year-oldwoman(height150cm,weight80kg,American Society ofAnesthesiologist II) wasscheduledfor umbilical herniarepair.Shewasdiagnosedtohaveasthmaandwason fluticasoneandsalmeteroltreatment.Shehadotherwiseno

∗_{Correspondingauthor.}

E-mail:[email protected](B.Basaran).

specificmedical history. Therewere noabnormalfindings during her preoperative examination, laboratory, respira-toryfunctiontest,electrocardiogramandchestX-ray.Thirty minutes before operation the patient was hydrated with 10mL/kglactatedringersolution.Onarrivalintothe operat-ingroom,routinemonitoringwasapplied.Forspinalblock 26gauge atracaun spinal needle wasused at L3---4 in the sitting position by a mid-line approach. A T4 block was

http://dx.doi.org/10.1016/j.bjane.2014.02.012

0104-0014/©2014SociedadeBrasileiradeAnestesiologia.PublishedbyElsevierEditoraLtda.ThisisanopenaccessarticleundertheCC

550 B.Basaranetal.

obtainedandBromagescorewasfourbeforesurgery.After midlinesurgicalincisionlargemultipleuterinmyomaswere noticed. Gynecologists decided tomake myomectomy for these large myomas after getting informed consent from herfamily.Frombeginningof thesurgeryvitalsignswere stable.Her average blood pressure110/60and heartrate 70---80beat/min.Threelitersofoxygenwereadministered bynasalcannula andheroxygensaturation was99---100%. Upon starting myomectomy the patient started to com-plainabout abdominaltendernessandfeeluncomfortable althoughsedated with0.05mg/kg midazolamand 1␮g/kg

fentanyl. Then we decided to induce general anesthesia. Afterinductionwith200mgpropofoland50mgrocuronium tracheawasintubated. Anesthesia wasmaintained O2---air

mixture(40:60), sevoflurane (2%) withcontrolled ventila-tionusingatidalvolumeof500mL,respiratoryrate12,PEEP 5mmHg.Thesurgerywasuneventful,andSpO2,ECG,ETCO2

andnoninvasivebloodpressurewasmonitoredcontinuously during operation. An abundant blood loss (about 500mL) duringthisfirstmyomectomywasseen;herSpO2andblood

pressure and ET CO2 fallen down to 80%, 65/40mmHg,

20 respectively. Left radial arterial cannula was inserted pH: 7.22, PO2: 45mmHg, PCO2: 40mmHg were detected

in arterial blood gas analysis.As a consequence of blood gasanalysisandherhemodynamicfailurewesuspectedthe venous air emboli. In order to visualize patient’s uterus and multiple large myomas, her uterus was exteriorized. Precordialauscultation at the apexof the heart revealed a mill-wheelmurmur. Thereafter we changed the patient position to left lateral recumbent position. We informed surgeonsabout possiblevenous airemboli. Surgeonsflood the surgical field with a normal saline. Air bubble image seenontransthoracicechocardiographyalsocorrectedour suspicion.100%oxygenwasadministered.PEEP in ventila-torsettingwasincreasedto10mmHg.To increasecentral venous pressure and replace blood loss the patient was hydratedwith1000cm3_{lactatedringersolutionand500cm}3

colloidin1h.Alongwithhydration10mg/hephedrine infu-sionaftertwo5mgbolusdosewasstarted.Within30minher bloodpressure,SpO2andETCO2valuesraisedgraduallyand

measured90/45mmHg,90%,30respectively.Arterialblood gasesatthistimeshowedpH:7.30,PO2:224mmHg,PCO2:

35mmHg.Afterthatmill-wheel murmurwasdisappeared. Thesurgerywascompletedinreverse trendelenburg posi-tion.Thepatientwasextubatedattheendofthesurgery, andreturnedfromintensive careunittothegeneralward onedayafterthesurgery.

Discussion

Venousairembolismis definedasentrapment ofair from damaged venous structure to the central venous system. Althoughvenousairembolismismostlyseen duringsitting positioncraniotomies,venousembolicanalsobeseen dur-ing cesarean section.1 _{Venous air emboli mechanism and} diagnosis during cesarean section were defined in many studies.2,3 _{The height difference between uterine} inci-sion and heart causes a negative pressure gradient thus encouraging air embolism. By the same mechanism, dur-ingabdominalmyomectomyexteriorizationofuteruscauses gravitationalgradientandleadtoentrapmentofairtothe damagedvenousvasculature.4

In our patient previously introduced spinal anesthesia decreased systemicvascularresistanceandcaused venous pooling. After induction systemic vascular resistance fell downfurther.Allthesefactorswouldbeanexplanationof thesesymptoms.Becauseinlowcardiacoutputstateslow ETCO2 can beseen.Asthma relatedbronchospasm mimics

thesamesymptomaticscenariotoo.

Preoperativehydrationandreplacementofbleedingloss with same amount of lactated ringer solution prevented deep hypotension. We did not see any high peak airway pressureand bronchospasmrelated ETCO2 pattern.Sowe

ruled out both possible two leading causes that may be an explanation of patient’s hemodynamic and respiratory alteration.

Venousairembolism(VAE)detectionduringobstetric pro-cedureswouldbeconsideredifunexplainedhypotensionand low level ofETCO2 are seentogether, or hypotensionand

hypoxiaarenotexplainedonlywithhypovolemia.

Since detection of VAE with transthoracic echocardio-gram,weexcludedpulmonarythromboembolismwhichmay beanotherreasonofthisscenario.

Currently, no any valuable data support emergent catheter insertionfor aspirationof air from right atrium. We decided to postpone the insertion of central venous line to the time when if any further hemodynamic and respiratorycompromiseseen.Afterallpreventiveand sup-portive measures patient’s hemodynamic and respiratory parameters were normalized, there wasno need for any interventionalanddiagnosticprocedure.

Inthemanagementprocesssurgeonsshouldbeinformed about suspicionof VAE.So the surgeon should check and coveranypossiblesiteofembolitoinhibitfurtherairentry. Hydrationtoincreasecentralvenouspressure,instanthigh oxygenpressuretomaximizepatientoxygenationand tren-delenburg position to optimize hemodynamics are other supportivetreatmentmethods.

Inconclusion,thiscaseshowsus,VAEmaybeseenduring myomectomy.AlthoughVAEshavedramaticconsequences, they can be handled conservatively if further preventive measuresprovidedinthecaseofsuspicion.

Conflicts

of

interest

Theauthorsdeclarenoconflictsofinterest.

References

1.MushkatY,LuxmanD,NachumZ,etal.Gasembolism compli-cating obstetric or gynecologic procedures. Case reports and review of the literature. Eur J Obstet Gynecol Reprod Biol. 1995;63:97---103.

2.LewTW,TayDH,ThomasE.Venousairembolismduringcesarean section:morecommonthanpreviouslythought.AnesthAnalg. 1993;77:448---52.

3.Fong J, Gadalla F, Druzin M. Venous emboli occurring cae-sareansection:theeffectofpatientposition.CanJAnaesth. 1991;38:191---5.