SURGICAL INFECTION 医疗7年制

SURGICALINFECTION ByDr ShiChengProfessorofSurgeryDepartmentofGeneralSurgeryBeijingTiantanHospitalCapitalMedicalUniversity Contents IntroductionClassificationInflammationandsystemicsurgicalinfectionSepsisFungalinfectionTetanusTheappropriateapplicationofantibiotics Introduction Classification SpecificandNonspecificinfection invasivemicro organismsSpecificinfection includingtuberculosis tentanus gasgangrene etal Nonspecificinfection pyogenic Acute subacuteandchronic duration twomonths Externalinfectionandinternalinfection invasiveway Opportunisticinfection superinfection nosocomialinfection conditions Inflammationandsystemicsurgicalinfection SYSTEMICINFLAMMATORYRESPONSESYNDROME SIRS Patientpresentswithtwoormoreofthefollowingcriteria 1 temperature 38 Cor90beats minute3 respiration 20 minorPaCO212 000 mm3 10 immature band cells Etiology Infectionfactor thecommoncause Sepsis Noninfectionfactor severetrauma burn pancreatitis shock ischemia reperfusioninjury Pathophysiology LocalinflammationSystemicinflammationTheroleofinflammationmediatorinSIRSRegulationandoutofcontroloftheinflammationresponse SIRS Sepsis Theconcepts SepsisThesystemicinflammatoryresponsetoinfection SepsissyndromeSepsis SIRS associatedwithorgandysfunction hypoperfusion orhypotension Hypoperfusionandperfusionabnormalitiesmayinclude butarenotlimitedto lacticacidosis oliguria oranacutealterationinmentalstatus Bacteremia Thepresenceofviablebacteriaincirculatingblood SystemicFactorscontributingtotheincreasingincidenceofsepsis 1 Miscellaneousconditions childbirth septicabortion traumaandwidespreadburns intestinalulceration 2 widespreaduseofcorticosteroidandimmunosuppressivetherapiesfororgantransplantsandinflammatorydiseases3 longerlivesofpatientspredisposedtosepsis cirrhosisofliver diabetics malnutrition anemia cancerpatients neutropenia leukemia dysproteinemias patientswithmajororganfailure andwithgranulocytopenia 4 Neonatesandtheelderlyaremorelikelytodevelopsepsis ex groupBStreptococcalinfections 5 aggressiveoncologicalchemotherapyandradiationtherapy6 AIDS localconditionsatincreasedrisksofdevelopingsepsis 1 Openingtrauma burning perforationofgastrointestine surgery puncture2 increaseduseofinvasivedevicessuchassurgicalprotheses inhalationequipment andintravenousandurinarycatheters 3 Intraductalobstruction4 Foreignbodyornecrotictissue 5 Bloodobstacleoflocaltissue Etiology Gram negativebacteria Escherichiacoli Klebsiellapneumoniae Pseudomonasaeruginosa Proteusspp Serratiaspp Neisseriameningitidis Gram positivebacteria Staphylococcusaureus coagulase negativeStaphylococcus Streptococcuspneumoniae Streptococcuspyogenes enterococci Othercauses Opportunisticfungi 2 to3 viral rickettsia andprotozoa OutcomeofInfecion ResolutionAbscessFormationDiffusionChronicinflammation ClinicalManifestations PrimaryinfectionfocusSystemicinflammationresponseHypoperfusionabnormalitiesoforgans Systemicinflammationresponse Fever chills Theymaybeabsentinseriousinfections especiallyinelderlyindividuals WBC leukocytosiswithleftshiftTachycardia tachypneaTachypneaaccompaniedwithmildrespiratoryalkalosisandalterationinmentalstatusmaybetheonlysignoftheelder Hypoperfusionabnormalitiesoforgans lacticacidosis oliguria Tachypnea hypoxia Pao2 Anacutealterationinmentalstatus Hyperbilirubinemia thrombocytopenia Septicshock organfailure PhysicalExamination MildenlargementofliverorspleenSkineruption reddishpatches Metastaticabscess Diagnosis DiseaseEvidenceBacteremiaPositivebloodcultureSepsisTheevidenceofinfectionthemanifestationofSIRSSepsissyndromePositivebloodculturetheevidenceofsepsisHypoperfusionoforganshypoxemia oliguria alterationinmentalstatus Diagnosis Gram positivebacteriasepsisGram negativebacteriasepsisCandidaalbicanssepsisAnaerobicbacteriasepsis Differentsepsisclinicalcharacters SepsiscommonpathogenicfeverchillshockrashdiseasebacteriametastaticabscessG CarbuncleStaphylococcuscontinued warm CellulitisaureusremittentlatepyogenicinfectionofboneandjointG biliary urinaryEscherichiaintermittent cold intestinalinfectioncoliearlyseriousburnCandidaafterapplyingCandidas albicansbroad spectrumalbicanantibioticsAnaerobicseriousinfectionBacteroidesbacteriaabdominalandfragilis metastaticabscesspelviccavity Therapy Theoriginalfocusofinfectionmustbetreatedsurgicaldrainagemaybeneededinsomecases Theapplicationofantibiotics PatientswithseveresepsisshouldbeinICU Supporttherapy InhibitionorblockadeofinflammationmediatorMonoclonalantibodiesagainstgram negativeendotoxin steroids andanti TNFantibodieshavenotdemonstratedsignificantreduction Recentstudysuggestslow dosesteroidsmayhelpinsepticshock butthisisnotyetstandardofcare Introduction Surgicalfungalinfectionisanopportunisticinfection Thedeeperinfectionisthemajor MostsurgicalfungalinfectionsareinfactduetoCandida butAspergillusinfectionsarealsoseen Pathogenesis C albicansisanasexual diploid dimorphicfungusthatiswidespreadonhumansandintheirenvironment Westilldon tunderstandwhythiscommoncommensalsometimesbecomespathogenic althoughimpairedhostdefencemechanismsseemcrucial Riskfactorsforopportunisticfungalinfections 1 Neutropaenicpatientsfollowingchemotherapy andotheroncologypatientswithimmunesuppression 2 PersonsimmunecompromisedduetoAcquiredImmuneDeficiencySyndromecausedbyHIVinfection 3 Patientsinintensivecare ICU whoarenotnecessarilyneutropaenic butarecompromisedduetothepresenceoflong termintravascularlinesorotherbreachesintheirintegument severesystemicillnessorburns andprolongedbroad spectrumantibiotictherapy Other quoted predisposingfactors APACHEscore 10 renaldysfunction haemodialysis surgeryforacutepancreatitis orevenpossiblysplenectomy recurentGITperforation Hickmanncatheters Clinicalmanifestations C albicanscausedigestivetract respiratorytractandurinarytractinfection BlooddisseminatedcandidiasisAspergilluscausepneumonia Diagnosis Ifyoudon tsuspectit you llmissit Conventionaldiagnosisoftheseinfections basedonbloodculturesorcultureoftheoffendingorganismfrommultiplesites Newerteststhathavebeenadvocatedforearlydiagnosisofsystemicfungalinfectioninclude SandwichELISAforcirculatinggalactomannan PCRshowspromiseinthediagnosisofCandidainfections evenunusualspecies Treatment Therapytoetiology Antifungaltherapy AmphotericinB0 5 1mg kg divFluconazoleandotherAzoles400mg firstday 200 400mg d Prevention AppropriateapplyingantibioticsProphylacticapplyingantifungaldrugs Whatistetanus Tetanusisanacute sometimesfatal diseaseofthecentralnervoussystem causedbythetoxinofthetetanusbacterium whichusuallyentersthebodythroughanopenwound Pathogenesis TetanusresultsfrominfectionwithCtetani amobile spore forming anaerobic gram positivebacillus Thisbacillusisfoundinoronsoil manure dust clothing skin and10 25 ofhumanGItracts Thesporesneedtissuewiththeproperanaerobicconditionstogerminate theidealmediumiswoundswithtissuenecrosis Pathogenesis ThesporesofCtetanigerminateandproduce2toxins tetanolysinandtetanospasmin Theactionofthelatterhelpsexplaintheclinicalmanifestationsofthedisease Pathogenesis Tetanospasminissynthesizedasasingle151 kdchainandiscleavedtogeneratetoxinswith2chainsjoinedbyasingledisulfidebond Theheavychain 100kd isresponsibleforspecificbindingtoneuronalcellsandforproteintransport Thelightchain 50kd blocksthereleaseofneurotransmitters Pathogenesis Oncethetoxinissynthesized itmovesfromthecontaminatedsitetothespinalcordin2 14days Whenthetoxinreachesthespinalcord localizedorcephalictetanusmayoccurinitially followedbygeneralizedtetanus ClinicalManifestation IncubationTheincubationperiodfortetanusisusually2to14days withmostsymptomsbeginningaroundthe7 8day butonsetmayrangefrom24hoursto3weeks ClinicalManifestation Tetanusoftenbeginswithmusclespasmsinthejaw calledtrismus accompaniedbydifficultyswallowingandstiffnessorpaininthemusclesoftheneck shoulders orback Thesespasmscanspreadtothemusclesoftheabdomen upperarms andthighs Symptoms stiffnessofjaw alsocalledlockjaw difficultyswallowingcontractionoffacialmusclesstiffnessofabdominalandbackmusclesSweatingpainfulmusclespasmsnearthewoundarea iftheseaffectthelarynxorchestwall theymaycauseasphyxiation Physical Commonfirstsignsoftetanusareheadacheandmuscularstiffnessinthejaw ie lockjaw followedbyneckstiffness difficultyswallowing rigidityofabdominalmuscles spasms andsweating Severetetanusresultsinopisthotonos flexionofthearms extensionofthelegs periodsofapnearesultingfromspasmoftheintercostalmusclesanddiaphragm andrigidityoftheabdominalwall Lateinthedisease autonomicdysfunctiondevelops withhypertensionandtachycardiaalternatingwithhypotensionandbradycardia Complications Themostcommoncomplicationisspasmofthevocalcordsand orspasmsoftherespiratorymusclesthatcauseinterferencewithbreathing Asphyxiation pneumoniaOthercomplicationsincludemuscleavulsion fractures dislocationstachycardia andheartfailure DIFFERENTIALS RabiesEncephalitisStrychninepoisoningOtherProblemstobeConsidered DentalinfectionsLocalinfectionsHysteria Prevention Therearetwoimportantcomponentsoftetanusprevention tetanusimmunization receivingroutinetetanusvaccinations andwhat sknownaspost exposuretetanusprophylaxis receivingashotafteraninjuryoccurs Prevention Forchildren tetanusimmunizationispartoftheDTaP diphtheria tetanus andacellularpertussis vaccinations ActiveimmunizationPost exposuretetanusprophylaxisalsoinvolvesgettingtetanusshots butafteraninjuryoccurs Passiveimmunization Treatment ThoroughcleaningofthewoundNeutronlizethefreetoxinPassiveimmunizationwithhumantetanusimmuneglobulin TIG shortensthecourseoftetanusandmaylessenitsseverity Adoseof500Uappearsaseffectiveaslargerdoses OrTAT20000 50000UIV Treatment TocontrolspasmsDiazepamiv 10mgtid Luminal0 1im Physiciansalsousesedativehypnotics narcotics inhalationalanesthetics neuromuscularblockingagents andcentrallyactingmusclerelaxants eg intrathecalbaclofen Treatment Securinganadequateairway Atracheotomyinseverecases withrespiratoryproblems AntibioticsMetronidazole eg 0 5gq6h hascomparableorbetterantimicrobialactivity andpenicillinisaknownantagonistofGABA asistetanustoxin Treatment SupportivetherapyParenteralnutritionIntensivenursing Theappropriateapplicationofantibiotics Background Theglobalincreaseinresistancetoantimicrobialdrugs includingtheemergenceofbacterialstrainsthatareresistanttoallavailableantibacterialagents hascreatedapublichealthproblemofpotentiallycrisisproportions Theroleofantibiotics InhibitscellwallsynthesisImpairmentofbacterialDNAsynthesisDisruptionofmembranebarrierfunctionDisruptionofribosomalproteinsynthesis ThecommonusedAntibiotics A AmphotericinBB PenicillinC CephalosporinsD lactamase ImipenemE AminoglycosidesF QuinolonesG ClindamycinH Antianaerobic microbacterialdrugs Prophylacticuseofantibioticsperioperativeperiod Indication 1 Severetrauma severeburn Anywoundwithknowngrossbacterialcontamination 2 Operationsenteringthegastrointestinaltract respiratorytract femalegenitaltractandbowelpreparationbeforecolonsurgery 3 Implantationofanypermanentprostheticmaterial 4 Highriskfactorofinfection Diabetesmellitus elder malnutrition granulocytopenia Steroids Immunosuppression oncologicalchemotherapyetal 5 Cardiacvalvulardiseaseorvalvesurgery organtransplantation Craniotomy Administrationofprophylacticantibiotics ChoiceofantibioticsTimingofadministrationDosageselectionDurationofprophylaxisRouteofadministration GuidelinesforUse ChoiceofantibioticsTheantibioticsselectedforprophylaxismustcovertheexpectedpathogensforthatoperativesite CephalosporinRecommeded Cefuroxime 2ndgenerationcephalosporin GuidelinesforUse Timingofadministration