Comparison of effects on the oxidant/antioxidant system of sevoflurane, desflurane and propofol infusion during general anesthesia

REVISTA

BRASILEIRA

DE

ANESTESIOLOGIA

www.sba.com.br

SCIENTIFIC

ARTICLE

Comparison

of

effects

on

the

oxidant/antioxidant

system

of

sevoflurane,

desflurane

and

propofol

infusion

during

general

anesthesia

Mesut

Erbas

_,

_Yavuz

_Demiraran

_,

_Hayriye

_Ak

_Yildirim

_,

_Gulbin

_Sezen

_,

Abdulkadir

Iskender

_,

_Ibrahim

_Karagoz

_,

_Hayati

_Kandis

a_{DepartmentofAnesthesiologyandReanimation,MedicalFaculty,C¸anakkaleOnsekizMartUniversity,Canakkale,Turkey} b_{DepartmentofAnesthesiologyandReanimation,MedicalFaculty,DuzceUniversity,Duzce,Turkey}

c_{DepartmentofBiochemistry,MehmetAkifErsoyThoracicandCardiovascularSurgeryTrainingandResearchHospital,Istanbul,}

Turkey

d_{DepartmentofEmergencyMedicine,MedicalFaculty,DuzceUniversity,Duzce,Turkey}

Received12February2014;accepted2May2014 Availableonline3June2014

KEYWORDS Oxidant; Antioxidant; Propofol; Generalanesthesia Abstract

Backgroundandobjectives: Desfluraneandsevoflurane arefrequently usedfor maintenance ofanesthesiaandstudieshaveshownthattheseanestheticscauseavarietyofchangestothe oxidativestressandantioxidativedefensemechanisms.Thisstudyaimstocomparetheeffects ofsevoflurane, desflurane andpropofol infusion anesthesiaon theoxidant andantioxidant systemsofpatientsundergoinglaparoscopiccholecystectomy.

Methods:45 patients between 18 and50 years with planned laparoscopic cholecystectomy undergeneralanestheticwereincludedinthestudy.Patientsweredividedintothreegroups onthewaytosurgery:propofol(groupPn:15),sevoflurane(groupSn:15)anddesflurane(group Dn:15).Allgroupsweregivenhypnotic2mg/kgpropofolIV,1mcg/kgfentanylIVand0.1mg/kg vecuroniumIVforinduction.FormaintenanceofanesthesiagroupSwereventilatedwith2% sevoflurane,groupDcasesweregiven6%desfluraneandgroupPweregivenpropofolinfusions of12mg/kg/hforthefirst10min,9mg/kg/hforthesecond10minand6mg/kg/hafterthat. Before inductionandafter theoperationvenousbloodsamples weretaken toevaluatethe levelsofglutationperoxidase,totaloxidantsandantioxidants.

Resultsandconclusions: The45 patientsincludedinthestudywere 22maleand23female patients. The demographic characteristicsof thegroups were similar. In the postoperative periodweobservedthatwhilesevofluraneandpropofolincreasedantioxidantsbyastatistically significantlevel,desfluraneincreasedthetotaloxidantslevelbyasignificantamountcompared tolevelsbeforetheoperation.

©2014SociedadeBrasileiradeAnestesiologia.PublishedbyElsevier EditoraLtda.Allrights reserved.

∗_{Correspondingauthor.}

E-mail:demiraran@gmail.com(Y.Demiraran).

http://dx.doi.org/10.1016/j.bjane.2014.05.004

PALAVRAS-CHAVE Oxidante;

Antioxidante; Propofol; Anestesiageral

Comparac¸ãodosefeitosdaperfusãodesevoflurano,desfluranoepropofolsobreo

sistemaoxidante/antioxidanteduranteanestesiageral

Resumo

Justificativaeobjetivos: Desflurano e sevoflurano são usados com frequência para a manutenc¸ãodaanestesia,eestudosmostraramqueessesanestésicoscausamalterac¸ões vari-adas nosmecanismos dedefesa antioxidante contrao estresseoxidativo. Este estudoteve como objetivocompararosefeitosdeanestesias comperfusão desevoflurano,desfluranoe propofolsobreossistemasoxidante/antioxidantedepacientessubmetidosàcolecistectomia laparoscópica.

Métodos: Foramincluídosnoestudo45 pacientesentre18 e50anos, agendadospara cole-cistectomialaparoscópicasobanestesiageralforamincluídosnoestudo.Ospacientesforam divididosem trêsgruposparareceberempropofol(GrupoP,n:15),sevoflurano(GrupoS,n: 15)edesflurano(GrupoD,n:15).Todososgruposreceberam2mg/kgdepropofolIV,1mcg/kg de fentanilIVe 0,1mg/kg devecurônioIV para induc¸ão.Para manutenc¸ãodaanestesia, o GrupoSrecebeuventilac¸ãocomsevofluranoa2%,oGrupoDrecebeudesfluranoa6%eoGrupo Precebeupropofolemperfusõesde12mg/kg/hnosprimeiros10min,9mg/kg/hnos10min seguintes e6mg/kg/h subsequentemente.Antesda induc¸ão edepoisda cirurgia,amostras desanguevenosoforamcolhidasparaavaliarosníveisdeglutationaperoxidaseeototalde oxidanteseantioxidantes.

Resultadoseconclusões: Dos45pacientesincluídosnoestudo,22eramdosexomasculinoe 23dosexofeminino.Ascaracterísticasdemográficasdosgruposeramsemelhantes.Noperíodo pós-operatório,observamosqueenquantosevofluranoepropofolaumentaramosantioxidantes a um nível de significância estatística,desflurano aumentou onível total deoxidantes em quantidadesignificativa,emcomparac¸ãocomosníveispré-operac¸ão.

©2014SociedadeBrasileira deAnestesiologia.PublicadoporElsevierEditoraLtda.Todosos direitosreservados.

Introduction

Free oxygen radicals, on the one hand while they

oxi-dizebiologicalmoleculessuchasthebody’sbuildingblocks

of protein, lipid and DNS, on the other hand they can

work against this oxidation as part of the body’s natural antioxidantdefensesystem.Thissituationisbalancedunder normalphysiological conditions.Howeverinasituationof meetinganystress,asaresultofincreasingantioxidant con-sumptionor freeradicalcreation,manyoxidative stresses increase.1,2 _{Many antioxidant molecules are found in the} bloodtopreventorinhibittheharmfuleffectsoffree oxy-genradicals.Measurementoftotalantioxidantandoxidant levels in plasma can be used to determine the oxidative stress reactionofthe organism.3,4 _{Desfluraneand} sevoflu-ranearefrequentlyusedformaintenanceofanesthesiaand studieshave shownthat theseanestheticscausea variety ofchangestotheoxidativestressandantioxidativedefense mechanisms.5_{Thechemicalstructureofpropofolissimilar} tosomefreeradicalconsumerssuchasendogenousvitamin Eandbutylatedhydroxenetoluene.6---8

Inthisstudyweaimedtocomparetheeffectsof sevoflu-rane, desflurane and propofol infusion anesthesia on the oxidant and antioxidant systems of patients undergoing laparoscopiccholecystectomy.

Methods

Afterpermissionwasgivenby2009/12no.decisionofDuzce UniversityMedicalFacultyClinicalStudyEthicsCommittee

and informed patient consent was obtained, 45 patients ASAI---IIbetween18and50yearswithplannedlaparoscopic cholecystectomyundergeneralanestheticwereincludedin thestudy.Patientswere dividedinto threegroups onthe waytosurgery:TIVA(groupPn:15),sevoflurane(groupSn: 15)anddesflurane(groupDn:15).Patientswithendocrine dysfunction,bloodtransfusionintheprevious2weeks,signs ofinfectionandinflammation,historyofpreoperative med-icationuse,anemia,andhemorrhagerequiring transfusion duringtheoperation wereexcluded fromthestudy.After fasting for 8h all patients in the study were given 1mg midazolamIV for premedication 30min beforethe opera-tion.Patientswere taken tothe operatingroom.Routine monitoring withelectrocardiogram (ECG), peripheral oxy-gensaturation(SPO2),andnon-invasivebloodpressurewere

done.Laterbeforetheoperationvenousbloodwastakento evaluatetotaloxidantstatus,totalantioxidantstatusand glutationperoxidaselevels.

All groups were given hypnotic 2mg/kg propofol IV, 1mcg/kgfentanylIVand0.1mg/kgvecuroniumIVfor induc-tion. During anesthesia induction cases were oxygenized with100%O2at6L/minflowrate.After3minofcontrolled

ventilation,usinganappropriateintubationtubeforageand weight,orotracheal intubation wascompleted. For main-tenance of anesthesia, group S were ventilated with 2% sevoflurane,50%airand50%O2mixat6L/minflow.Group

Dcasesweregiven6%desflurane,50% airand50%O2mix

at 6L/min flow.Group Pwere givenpropofol infusionsof 12mg/kg/hfor thefirst 10min, 9mg/kg/hfor the second 10minand6mg/kg/hafterthat.Patientswereventilated with50%air and50%O2 mixat 6L/minflow.In allgroups

aftertidalvolumewasdeterminedtobe6---8mg/kgand res-pirationratewas12,ventilationwasbegunwithanAvance S/5anesthesiadevice.Tenminutesbeforetheexpectedend ofsurgerypropofolinfusionwasended.Whenthelastskin suturewasbeingmadeinhalationagentswereshutoff. Man-ualventilationwith100%O2wasundertaken.Inthisperiod

allparametricreadingsweretaken.Afterspontaneous respi-rationbegan,neuromuscularantagonizationwascompleted with0.01mg/kgatropineand0.03mg/kgneostigmine.After extubationthepatientwastakentorecovery.Latervenous blood was taken to evaluate total oxidant status, total antioxidantstatusandglutationperoxidaselevelsafterthe operation.

Biochemicalanalysis

Bloodsamplestakeninanticoagulantfreevacuumgeltubes werecentrifugedat2000×gfor15min.Theserumwas por-tioned into clean tubes. For glutation studies the serum separated in the tube was deproteinized. Forthe depro-teinizationprocedure5gmetaphosphoricacidwasdissolved in50mLdistilledwaterand200␮Lsamplesweremixedwith 200␮L metaphosphoric acid solution and vortexed. They wererestedat roomtemperature for5minandwere cen-trifugedat2000×gfor4min.Thesupernatantwascarefully separated to a different tube. This supernatant to mea-sureglutationandtheserumportionsdesignatedtomeasure otherparameterswerestoredat−80◦Cuntilmeasurements couldbemade.Glutationwasmeasuredbasedonenzymatic measurementsusingCayman (CaymanInc.,AnnArbor,MI, USA)commercialkits,whichuse5-thio-2-nitrobenzoicacid (TNB)toreactwiththeDTNB(5,5-dithio-bis-2-nitrobenzoic acid) of the sulfhydryl group in GSH glutation reductase formingayellowcolor.Onthedayofmeasurement,samples werethawedandmixed,thenprepared4Mtriethanolamine solutionof10␮Lwasaddedto200␮Lsamplesandvortexed. Aftersamplesweredilutedat1:2(v/v)ratiowithMESbuffer, standardswerepreparedaccordingtotheprospectus.They wereaddedto50␮mwells,andtheplatewascoveredwith thelid fromwithinthekit.Atthisstage,accordingtothe prospectusanassaycocktailofMESbuffer(11.25mL),GSH co-factormixture(0.45mL),GSHenzymemixture(2.1mL), distilledwater(2.3mL),andGSHDTNB(0.45mL)was pre-paredand150␮Lfreshly-preparedassaycocktailwasadded toall wells, the plate wascovered and incubated on an orbitalmixerinthedarkfor25min.Inthe25thminute mea-surementwastakenusingaBio-Rad680Microplatereader at414nm.TotalantioxidantmeasurementsusedaCayman (CaymanInc.,AnnArbor,MI,USA)commercialkitbasedon oxidationinhibitionofABTS•+bythemetmyoglobininABTS (2,2-azino-di-[3-ethylbenzthiazoline sulphonate]). On the dayofmeasurementsampleswerethawedandmixed,then forantioxidantmeasurementsthesamplesweredilutedwith assay buffer at 1:19 (v/v) and standards were prepared accordingtotheprospectus.After10␮Ltroloxstandardor 10␮L sample was added to all wells 10␮L metmyoglobin and 150␮L chromogen solutionwere added and to begin the reaction immediately 40␮L 441␮M antioxidant assay hydrogenperoxidewasadded.The platewascoveredand incubatedonamixeratroomtemperaturefor5min. Mea-surementwasmadeusingaBio-Rad680Microplatereader

at405nm.TotaloxidantcapacitymeasurementsusedaRel Assaykit(RelAssayDiagnostics, MegaTıpSanandTicLtd Sti, Turkey) developed by Erel.9 _{This method is based on} oxidants inthesample turningaferrousironchelatorinto ferricions,whichinanacidenvironmentformacolor com-plex with chromogen and this complex is then measured spectrophotometrically. Stabilized stock standard solution (SSSS) was diluted 40,000 times by deionized water then 150␮Lor the sample wasmixed with1000␮L reactive I. First absorbance was measured using a spectrophotome-terat530nmwavelength.Fifty␮Lprochromogensolution wasadded,mixedandincubatedat roomtemperaturefor 10min.Secondabsorbancewasmeasuredat530nm.

Forcalculationsthefollowingformulaewereused:

TOS=  Absorbancesample Absorbancestandard  ×standardvalue

Absorbance sample=2nd absorbance sample−1st absorbancesample,

Absorbance standard=2nd absorbance standard−1st absorbancestandard,

Standardvalue:20␮molH2O2equiv./L.

Statisticalanalysis

Data were analyzed using the SPSS v 11.5 (SPSS, Inc., Chicago,IL,USA)computerprogram.Distributionof numer-ical data within the groups was evaluated using the Shapiro---Wilktest.Datawithnormaldistributionaregiven asmean±standarddeviation(SD);categoricalvariablesare givenasfrequencies.Todetermineanydifferencesin aver-agenumericaldatabetweenthegroupstheone-wayANOVA wasused.Tofindgroups responsible forsignificant differ-encesmultivariateanalysisusedtheScheffetest.Beforeand aftermeasurementswereanalyzedwiththepairedsamples t test as they had normal distribution. Categorical varia-bleswerecomparedbetweenthegroupswiththechi-square test. Ap value <0.05 wasaccepted asstatistically signifi-cant.

Results

Ourstudycomprisedatotalof45 patients:15weregiven sevoflurane, 15 were given desflurane and 15 were given propofolinfusion.Ofthe45patients22weremaleand23 were femalepatients. Therewasnostatistical difference betweenthepatientsinthegroupsintermsofaverageage, weight,andanesthesiaduration(Table1)(p>0.05).

Hemo-Table1 Demographiccharacteristicsofpatients. GroupS GroupD GroupP p Age(years) 35±8 36±8 34±8 0.84 Heavy(kg) 69±9.3 68±8.8 67±8.6 0.92

Sex(M/F) 9/6 7/8 6/9

Anesthesiatime(min) 106_±13 113_±18 107_±10 0.43 M,male;F,female.

68

Group S Group D Group P

Pre-op 1. min 5. min _{15. min 30. min 60. min}

Post-op 1. minPost-op 5. min_{Post-op 15. min}

70 72 74 76 78 80 82 84

Figure1 Hemodynamicdatafromthegroups.

Table2 TAS,TOSandGSH-PXlevelsofpatients.

PREOP POSTOP p TAS(mmol/L) GroupS 0.6±0.1 0.8±0.2 0.02a GroupD 0.8_±0.2 0.7_±0.2 0.24 GroupP 0.6±0.1 0.7±0.1 0.04a TOS(mol/L) GroupS 7.1±4.5 10.5±6.4 0.07 GroupD 9.1±4.6 12.6±4.1 0.03b GroupP 8.4±6.3 6.4±4.2 0.10 GSH-PX(mmol/L) GroupS 0.7_±0 0.7_±0.1 0.42 GroupD 0.7±0.1 0.7±0.1 0.89 GroupP 0.8_±0.1 0.7_±0.1 0.79

a _{Thereisstatistically significantdifferenceinTASbetween}

thepreoperativeandpostoperativeperiodingroupsSandP. b _{ThereisstatisticallysignificantdifferenceinTOSbetween} thepreoperativeandpostoperativeperiodingroupD.

dynamicmonitoring of patientswascompletedduring the operation. During this monitoring the patients’ preopera-tive,intraoperativeandpostoperativemeanbloodpressure (MBP) was recorded (Fig. 1). The MBP values of patients in groups S, D and P were similar. It was observed that sevoflurane and propofol significantly increases the total antioxidantcapacity.Furthermorewefoundthatdesflurane significantlyincreasesthetotaloxidantcapacity.

TheTAS,TOSandglutationperoxidaselevelsofpatients beforeandaftertheoperationareshowninTable2.

Discussion

In this study we reached the conclusion that sevoflurane andpropofolhave antioxidantpropertieswhile desflurane increasedoxidativestress.

The aimof generalanestheticapplicationsis tocreate anesthesiaeffectivelywhilereducingtominimallevelsthe conditionsthatmay harmtheorganism. Anesthetic mate-rial appropriate for this aim should be pure and stable chemically, have quickonset andslowend to effect,and notcreateany unwantedeffects onvitalfunctions during andafteradministration.10_{Infactanestheticmaterialsand}

anesthetic duration used in general anesthesia, together withthestressofsurgicaltrauma,areimportantfactorsthat disruptthe body’simmunologicaland antioxidantdefense systems.11 _{Laparoscopicsurgeryexposes theparietal} peri-toneumandvisceralperitoneumtoischemictrauma.Studies have shown that if intraabdominal pressure is held at 15mmHgduringlaparoscopy,bloodflowtotheparietal peri-toneumreducesbyasignificantamount,whileat10mmHg there is no change. For this reason pneumoperitoneum maypotentially cause ischemia and increase free oxygen radicals.12 _{General anesthesia disruptsthe immunological} defense mechanisms and induces an inflammatory reac-tionin alveolarmacrophages.Ingeneralizedinflammatory reactionsincludingproductionofleukocytes,inflammation mediatorsandfreeoxygenradicalsarereleased.Membrane damagecaused byfree radicalsduringgeneral anesthesia presentsasobservedlipidperoxidationproducts.13 _Studies haveshownthatavarietyofmedicationsusedin anesthe-siahaveeffectsontheoxidant-antioxidantsystem.However theeffectontheantioxidantsystemoftheinhalation anes-theticdesfluranehasnotbeenfullystudied.Knowledgeof theinteractionsofinhalationagentusedonpatientsunder oxidativestresscarriesclinicalimportance.14_Baysaletal.15 examinedthetotaloxidativestatusandantioxidativestatus levelsofpediatricpatientsundergoinglaparoscopicsurgery andconcludedthatthesurgicalstressoflaparoscopy with inhalationanestheticsincreasedtotaloxidantcapacityand reducedtotalantioxidantcapacity.

Inrecentyearsmanystudiesontheantioxidantsystem havebeencompleted,thesestudiesfoundthatthe antiox-idant system has major effects on patient mortality and morbidity.16_{Antioxidantsystemsnormallyworkasawhole,} protectingcells fromthetoxiceffects ofoxygenradicals. Thismaintains theoxidant andantioxidantsystemsinthe organisminabalancedfashion.Insituationswherethis bal-anceisdisruptedtowardoxidation,inflammatorymediators andfreeoxygenradicalsareproducedbyleukocytes.These createlipidperoxidationincellmembranes,damagingDNA andcausingdisease.17

In our study we observed in the desflurane group total oxidant capacity, an indicator of oxidative stress, wasstatisticallyincreased,while antioxidantcapacitywas reduced,thoughnotatstatisticallysignificantlevels.Inthe sevofluranegroupoxidativestresswasincreasedcompared to values before the operation, though not significantly,

while antioxidant capacity was statistically significantly increased.Dikmenetal.18 _{lookedat theeffectof} sevoflu-raneon the enzymaticantioxidant defense system in the livers of rats and showed that sevoflurane produced an increase in lipid peroxidation before any insufficiency in the enzymatic antioxidant defense system. Allaouchiche et al.19 _{compared propofol (8mg/kg/h), desflurane (10%)} and sevoflurane (2.5%) to determine oxidative situation in pigs. Pigs were exposed to the anesthetic agents for about120min;propofolincreasedglutationperoxidase lev-els (GSH-Px) significantly in both bronchoalveolar lavage (BAL)fluidandincirculation.Desfluranecausedasignificant decreaseofGSH-PxinbothBALfluidandcirculation,while inthesevofluranegrouptherewerenosignificantchanges identifiedin BALfluidandincirculation. Theystatedthat oxidative stress due to desflurane anesthesia might be relatedtoextreme increasesinproinflammatorycytokines in alveolar macrophages. Sivaci et al.20 _{used sevoflurane} or desfluraneonpatients undergoinglaparoscopic surgery andobservedthatbothagentshadcytotoxiceffectsdueto freeradicalformation.Desfluranechangesoxidativestress and antioxidant mechanisms negatively; they stated that thenitrogen mixture usedwith desfluranemight increase thiseffectevenmore.Sivacietal.determinedthat desflu-ranereducedserumGSHlevels.Howeverwedidnotidentify anyeffectonserumGSHlevelsduetoeitherdesfluraneor propofol.

Propofol hasbeen found toincreasethe fluidityofthe erythrocytemembranepreventinghemolysis,similarto vita-min E, and shows antioxidant activity. Propofol protects erythrocytes from oxidative and physical stress. Ascorbic acidhasbeenshowntomakethiseffectmorepronounced. Inverselyvolatileanestheticsreduceerythrocytemembrane fluidity inducing hemolysis.21 _{In our study in the} propo-folinfusiongroup oxidativestressafterthe operationwas reducedcomparedtovaluesbeforeoperation,thoughnot significantly, while at the same time antioxidant capac-itywasstatisticallyincreasedafteroperation.In allthree groupsstatistically significantchanges inglutation peroxi-daselevelswerenotobserved.Inthepropofolinfusiongroup inthepostoperative periodtheywere alittlereduced,in thesevofluranegroupinthepostoperativeperiodtheywere alittleincreasedwhileinthedesfluranegroupnochanges wereobserved.Inourstudyinbothsevofluraneandpropofol infusiongroupsTASvaluesafteroperationwerestatistically significantlyincreasedcomparedtovaluesbeforesurgery.

Conclusion

Thisstudygivesanideathatingeneralanesthesia, neces-saryforavarietyofreasons,incasesunderoxidativestress theagentthatwillleastdamagetheantioxidantsystem,an importantcascadeinthehumoraldefensesystem,andthat willhaveleasteffectontheimmunesystemshouldbe cho-sen.Furtherresearchintotheimmunesituationofpatients receivinggeneralanestheticandtherelationshipbetween oxidant/antioxidantsystemsarerequired.

Conflicts

of

interest

Theauthorsdeclarenoconflictsofinterest.

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