产科麻醉英文版

ObstetricAnesthesiaDepartmentofanesthesiologyCuiXiaoGuangPHYSIOLOGICCHANGESOFPREGNANCY1CardiovascularSystem:cardiacoutput,heartrateHematologicSystem:bloodvolumeincreasesbyupto45%,redcellvolumeincreasesbyonly30%--physiologicanemiaRespiratorySystem:increaseintherespiratoryminutevolumeandworkofbreathingGastrointestinalSystem:riskofincidenceofaspiration↑endotrachealintubation:theriskRenalSystem:GFRrises50%;glycosuriaCentralNervousSystem:↑sensitivitytoanesthetics.PHYSIOLOGICCHANGESOFPREGNANCY2PLACENTALTRANSFEROFANESTHETICDRUGSPlacentatransport:SimplediffusionFacilitateddiffusionActivetransportPinocytosisReadilycross:lowmolecularweights,highlipidsolubility,non-ionizedApproximately50%oftheumbilicalvenousbloodbypassestheliver.MorphinePlacentaltransferisrapidMother:uterusreactiveness↓orthostatichypotensionnauseavomitingdelayedgastricemptyingFetus:respiratorydepressionPethidineMostcommonlyusedduringlaborintramusculardose:50-100mgTimeofIM:beforeexpulsion1hor4huterinecontraction,frequencyandintension↑FentanylAlfentanilSufentanilPlacentaltransferisrapidLowdose:10-25µgfentanylor5-10µgsufentanilinsubarachnoidspacePCEA:lowdoseoffentanyland0.1%-0.3%ropivacaineTramadolPlacentaltransferNoinhibitinguterinecontractionNoRespiratorydepressionDiazepamReadilycrosstheplacentaHalf-lives:48hoursProblems:sedation,hypotonia,cyanosis,impairedmetabolicresponsestostress.MidazolamPlasmaproteinbinding:94%Respiratorydepression:dependedondose0.075mg/kg–noproblem0.15mg/kg–differentdegreeChlorderazinPreeclampsiaandeclampsiaIM：12.5–25mgOverdose:centralinhibitionPromethazinePreventemesisAppearsinfetalbloodwithin1to2minutesafterintravenousinjectioninthemotherReachesequilibriumwithin15minutesDroperidolPregnantwoman:慎用Apgarscore↓ThiopentalsodiumNeonatussleep:littlePrematureandintrauterineembarrass:carefullyusingKetamineHighdoses(greaterthan2mg/kg)maycauselowApgarscoresandabnormalitiesinneonatalmuscletoneLaborpainsofuterinecontraction↓Uterinemusculartensionandcontractionforce↑Contraindication:psychosis,gestationalhypertensionsyndromeorpreeclampsia,metrorrhexisPropofolRecommendation:induction:2.5mg/kgmaintenance:2.5-5.0mg/kg/hDiscontinuegravidityonlyN2OPlacentaltransferisrapidMother’srespiration,circulationandUterinemuscularcontractionforce↑20-30sbeforeoffirststageoflabor:50%O2and50%N2O,maximum70%EnfluraneandIsofluraneLightanesthesia:noinhibitionDeepanesthesia:mother:inhibitionofuterinecontraction,uterinebleedingfetus:disadvantageSevofluranePlacentaltransferismorerapidthanhalothaneInhibitionofuterinecontraction:halothaneSuccinylcholineCholinesterase:normaldose→noplacentaltransferDose300mgorsingledoseislarger:stillhaveplacentaltransferNondepolarizingMuscleRelaxantsOnsetisquick,maintanenceisshortandplacentaltransferisleastAtracurium:0.3mg/kgLocalanestheticsFactors:Proteinbinding:MolecularweightLiposolubilityCatabolismintheplacentLocalanestheticsProcaineLidocaineBupivacaineRopivacaineANESTHESIAFORCESAREANSECTIONChoicedependson:theindicationsforthesurgerythedegreeofurgencymaternalstatusdesiresofthepatientSpinalAnesthesiaHyperbaricbupivacaineAdvantages:rapidonset,littleriskoflocalanesthetictoxicity,minimaltransfertothefetus,infrequentfailure.Disadvantages:finitedurationhypotensionheadacheEpiduralAnesthesiaL2～3orL1～21.5%～2%Lidocaineor0.5%RopivacaineemergencycesareansectionCombinedSpinal-EpiduralTechniqueIncreaseddramaticallyinpopularityAdvantages:rapidonsetsupplementedatanytimeanestheticdose↓sacralnervesblockissufficientGeneralAnesthesiarapidinduction:obviatepositivepressureventilationoppressthecricoidcartilagemainterance:lightansthesiavomiting,backstreamingandaspiration:atropine,0.5mg,IMorglycopyrolate,0.2mg,IMSupinehypotensivesyndromeIncidence:2%～30%Time:after28weeks,specially32～36weeksSymptoms:◆hypotension,◆dizziness,◆nausea,◆chestdistress,◆coldsweat,◆toyawn,◆pulserate↑,◆pallescenceMechanismPreventHighriskpregnancyEmergencyoperation:latetrimesterofpregnancy:hemorrhagegestationalhypertensionsyndromandeclampsiaSelectiveoperation:hypertensioncardiacdiseasediabetesmultifetationPlacentaPreviaandPlacentalAbruptionPreanesthticpreparation:bloodcoagulationfunctionDICsiftingtestacuterenalfailurePrinciple:generalanesthesia:activebleeding,hypovolemicshock,definitebloodcoagulationdisfunctionorDICintraspinalanesthesia:conditionofmotherandfetusisokayManagementdegreesofabruptioplacentae.A,Concealedhemorrhage.B,Externalhemorrhage.C,Completeplacentalseparation.Typesofplacentaprevia.ManagementofanesthesiaAnnouncementsoftheinduction:difficultairwaycricoidcartilagebackstreamingandaspirationPreparetosalvagethebloodcoagulationdisfunctionandthehemorrhoea.Preventtheacuterenalfunctionfailure:urinevolumeureanitrogenandcreatininePreventionandcureofDICPregnancy-inducedhypertensionsyndromeIncidence:10.3%Causeofdeath:cerebrovascularaccident,pneumonedema,livernecrosisPathophysiology:systemicarteriolasystole,200µm,calciumion,pachemia,hypovolemia→wholebloodandplasmaviscosity↑andhyperlipemia→microcirculationperfusion↓→intravascularcoagulationPregnancy-inducedhypertensionsyndro