阑尾炎(英文)

AnatomyVariedanatomyLength:5~10cm,narrowlumenhaustraofcolonEpidemiologyThemostcommonacuteabdomendiseaseTheincidenceofappendectomyappearstobedecliningduetomoreaccuratepreoperativediagnosis.Despitenewerimagingtechniques,acuteappendicitiscanbeverydifficulttodiagnose.PathophisiologySimpleappendicitisSuppurativeappendicitisGangrenousappendicitisPerforatedappendicitisPeritonitisAbscessaroundtheappendixMucoceleofappendixPathophysiologyAcuteappendicitisisthoughttobeginwithobstructionofthelumenObstructioncanresultfromfoodmatter,adhesions,orlymphoidhyperplasiaAppendixistwisted,andLumenofappendixisnarrow,resultinobstructionMucosalsecretionscontinuetoincreaseintraluminalpressureEtiology1.Theanatomycharacteristics2.Thetissuefeatures3.fecality,foreignbodyobstruction4.Parasitescausethemucosadamage5.adhesion,pressurecauseappendixdistortedObstruction→highpressure→limphobstructed,ischemia→mucosadamage→bacteriainvade（70%～80%）ArteryTheappendixarteryhasnobranches,iseasilytobeobstacledEtiologyEventuallythepressureexceedscapillaryperfusionpressureandvenousandlymphaticdrainageareobstructed.Withvascularcompromise,epithelialmucosabreaksdownandbacterialinvasionbybowelfloraoccurs.microbes：Ecoli,streptococcus,Pseudomonas,anaerobeEtiologyIncreasedpressurealsoleadstoarterialstasisandtissueinfarctionEndresultisperforationandspillageofinfectedappendicealcontentsintotheperitoneumPathophysiologyInitialluminaldistentiontriggersvisceralafferentpainfibers,whichenteratthe10ththoracicvertebrallevel.Thispainisgenerallyvagueandpoorlylocalized.Painistypicallyfeltintheperiumbilicalorepigastricarea.PathophysiologyAsinflammationcontinues,theserosaandadjacentstructuresbecomeinflamedThistriggerssomaticpainfibers,innervatingtheperitonealstructuresTypicallycausingpainintheRLQPathophysiologyThechangeinstimulationformvisceraltosomaticpainfibersexplainstheclassicmigrationofpainintheperiumbilicalareatotheRLQseenwithacuteappendicitis.PathophysiologyExceptionsexistintheclassicpresentationduetoanatomicvariabilityoftheappendixAppendixcanberetrocecalcausingthepaintolocalizetotherightflankInpregnancy,theappendixcanbeshiftedandpatientscanpresentwithRUQpainPathophysiologyInsomemales,retroilealappendicitiscanirritatetheureterandcausetesticularpain.Pelvicappendixmayirritatethebladderorrectumcausingsuprapubicpain,painwithurination,orfeelingtheneedtodefecateMultipleanatomicvariationsexplainthedifficultyindiagnosingappendicitisManifestationsPrimarysymptom:abdominalpain½to2/3ofpatientshavetheclassicalpresentationPainbeginninginepigastriumorperiumbilicalareathatisvagueandhardtolocalizeManifestationsAstheillnessprogressesRLQlocalizationtypicallyoccursRLQpainwas81%sensitiveand53%specificfordiagnosisMigrationofpainfrominitialperiumbilicaltoRLQwas64%sensitiveand82%specificManifestationsAssociatedsymptoms:indigestion,discomfort,flatus,needtodefecate,anorexia,nausea,vomitingAnorexiaisthemostcommonofassociatedsymptomsVomitingismorevariable,occuringinabout½ofpatientsPhysicalExamFindingsdependondurationofillnesspriortoexam.EarlyonpatientsmaynothavelocalizedtendernessWithprogressionthereistendernesstodeeppalpationoverMcBurney’spointPhysicalExamRovsing’ssign:paininRLQwithpalpationtoLLQObturatorsign:passivelyflextheRhipandkneeandinternallyrotatethehip.IfthereisincreasedpainthenthesignispositivePhysicalexamPsoassign:placepatientinLlateraldecubitusandextendRlegatthehip.Ifthereispain,thesignispositive.Rectalexam:paincanbemostpronouncedifthepatienthaspelvicappendixPhysicalExamAdditionalcomponentsthatmaybehelpfulindiagnosis:reboundtenderness,voluntaryguarding,muscularrigidity,tendernessonrectalFever:anotherlatefinding.Attheonsetofpainfeverisusuallynotfound.Temperatures39Careuncommoninfirst24h,butcommonafterruptureDiagnosisAcuteappendicitisshouldbesuspectedinanyonewithepigastric,periumbilical,rightflank,orrightsidedabdpainwhohasnothadanappendectomyWomenofchildbearingageneedapelvicexamandapregnancytest.Additionalstudies:CBC,UA,imagingstudiesDiagnosisTheWBCisoflimitedvalue.SensitivityofanelevatedWBCis70-90%,butspecificityisverylow.But,+predictivevalueofhighWBCis92%and–predictivevalueis50%CRPandESRhavebeenstudiedwithmixedresultsDiagnosisImagingstudies:includeX-rays,US,CTXraysofabdareabnormalin24-95%Abnormalfindingsinclude:fecalith,appendicealgas,localizedparalyticileus,blurredrightpsoas,andfreeairAbdominalxrayshavelimiteduse:forthefindingsareseeninmultipleotherprocessesDiagnosisLimitationsofUS:retrocecalappendixmaynotbevisualized,perforationsmaybemissedduetoreturntonormaldiameterDiagnosisCT:bestchoicebasedonavailabilityandalternativediagnoses.Inonestudy,CThadgreatersensitivity,accuracy,-predictivevalueSpecialPopulationsVeryyoung,veryold,pregnant,andHIVpatientspresentatypicallyandoftenhavedelayeddiagnosisHighindexofsuspicionisneededinthethesegroupstogetanaccuratediagnosisTreatmentAppendectomyisthestandardofcarePatientsshouldbegivenIVF,andpreoperativeantibioticsAntibioticsaremosteffectivewhengivenpreoperativelyand