Position paper: management of perforated sigmoid diverticulitis

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Title:
Position paper: management of perforated sigmoid diverticulitis
Series Title:
World Journal of Emergency Surgery
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Creator:
Frederick A Moore
Fausto Catena
Ernest E Moore
Ari Leppaniemi
Andrew B Peitzmann
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World Journal of Emergency Surgery
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Subjects / Keywords:
Complicated diverticulitis
Hartmann’s procedure
Primary resection anastomosis
Laparoscopic lavage and drainage
Percutaneous drainage

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Abstract:
Over the last three decades, emergency surgery for perforated sigmoid diverticulitis has evolved dramatically but remains controversial. Diverticulitis is categorized as uncomplicated (amenable to outpatient treatment) versus complicated (requiring hospitalization). Patients with complicated diverticulitis undergo computerized tomography (CT) scanning and the CT findings are used categorize the severity of disease. Treatment of stage I (phlegmon with or without small abscess) and stage II (phlegmon with large abscess) diverticulitis (which includes bowel rest, intravenous antibiotics and percutaneous drainage (PCD) of the larger abscesses) has not changed much over last two decades. On the other hand, treatment of stage III (purulent peritonitis) and stage IV (feculent peritonitis) diverticulitis has evolved dramatically and remains morbid. In the 1980s a two stage procedure (1st - segmental sigmoid resection with end colostomy and 2nd - colostomy closure after three to six months) was standard of care for most general surgeons. However, it was recognized that half of these patients never had their colostomy reversed and that colostomy closure was a morbid procedure. As a result starting in the 1990s colorectal surgical specialists increasing performed a one stage primary resection anastomosis (PRA) and demonstrated similar outcomes to the two stage procedure. In the mid 2000s, the colorectal surgeons promoted this as standard of care. But unfortunately despite advances in perioperative care and their excellent surgical skills, PRA for stage III/IV diverticulitis continued to have a high mortality (10-15%). The survivors require prolonged hospital stays and often do not fully recover. Recent case series indicate that a substantial portion of the patients who previously were subjected to emergency sigmoid colectomy can be successfully treated with less invasive nonoperative management with salvage PCD and/or laparoscopic lavage and drainage. These patients experience a surprisingly lower mortality and more rapid recovery. They are also spared the need for a colostomy and do not appear to benefit from a delayed elective sigmoid colectomy. While we await the final results ongoing prospective randomized clinical trials testing these less invasive alternatives, we have proposed (based primarily on case series and our expert opinions) what we believe safe and rationale management strategy.

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REVIEWOpenAccessPositionpaper:managementofperforated sigmoiddiverticulitisFrederickAMoore1*,FaustoCatena2,ErnestEMoore3,AriLeppaniemi4andAndrewBPeitzmann5AbstractOverthelastthreedecades,emergencysurgeryforperforatedsigmoiddiverticulitishasevolveddramaticallybut remainscontroversial.Diverticulitisiscategorizedasuncomplicated(amenabletooutpatienttreatment)versus complicated(requiringhospitalization).Patientswithcomplicateddiverticulitisundergocomputerizedtomography (CT)scanningandtheCTfindingsareusedcategorizetheseverityofdisease.TreatmentofstageI(phlegmonwith orwithoutsmallabscess)andstageII(phlegmonwithlargeabscess)diverticulitis(whichincludesbowelrest, intravenousantibioticsandpercutaneousdrainage( PCD )ofthelargerabscesses)hasnotchangedmuchoverlast twodecades.Ontheotherhand,treatmentofstageIII(purulentperitonitis)andstageIV(feculentperitonitis) diverticulitishasevolveddramaticallyandremainsmorbid.Inthe1980satwostageprocedure(1st-segmental sigmoidresectionwithendcolostomyand2nd-colostomyclosureafterthreetosixmonths)wasstandardofcare formostgeneralsurgeons.However,itwasrecognizedthathalfofthesepatientsneverhadtheircolostomy reversedandthatcolostomyclosurewasamorbidprocedure.Asaresultstartinginthe1990scolorectalsurgical specialistsincreasingperformedaonestageprimaryresectionanastomosis( PRA )anddemonstratedsimilar outcomestothetwostageprocedure.Inthemid2000s,thecolorectalsurgeonspromotedthisasstandardofcare. Butunfortunatelydespiteadvancesinperioperativecareandtheirexcellentsurgicalskills, PRA forstageIII/IV diverticulitiscontinuedtohaveahighmortality(10-15%).Thesurvivorsrequireprolongedhospitalstaysandoften donotfullyrecover.Recentcaseseriesindicatethatasubstantialportionofthepatientswhopreviouslywere subjectedtoemergencysigmoidcolectomycanbesuccessfullytreatedwithlessinvasivenonoperativemanagement withsalvage PCD and/orlaparoscopiclavageanddrainage.Thesepatientsexperienceasurprisinglylowermortality andmorerapidrecovery.Theyarealsosparedtheneedforacolostomyanddonotappeartobenefitfromadelayed electivesigmoidcolectomy.Whileweawaitthefinalresultsongoingprospectiverandomizedclinicaltrialstestingthese lessinvasivealternatives,wehaveproposed(basedprimarilyoncaseseriesandourexpertopinions)whatwebelieve safeandrationalemanagementstrategy. Keywords: Complicateddiverticulitis,Hartmann ’ sprocedure,Primaryresectionanastomosis,Laparoscopiclavageand drainage,PercutaneousdrainageIntroductionThispositionpaperupdatestheliteraturerelatedtothe managementofperforatedsigmoiddiverticulitiswiththe goalsofidentifyinga)keymanagementdecisions,b)alternativemanagementoptionsandc)gapsinourknowledgebasethatcanbetargetedinafutureemergency surgeryresearchagenda[1,2].Fromthiswehavecreated adecisionmakingalgorithmthatcanbemodifiedbased onevolvingevidenceandlocalresourcestoguideinstitutionalpractices.Thismanuscriptwillprovidethebasis forafutureevidencebasedguideline(EBG)thatwillbe developedandendorsedbytheWorldSocietyofEmergencySurgeryandpublishedintheWorldJournalof EmergencySurgery.WeenvisionthattheEBGrecommendationswillbegradedbasedonthelevelofevidence andwillidentifytheresourcesneededtoprovideoptimal care.Recognizingthetremendousvariabilityinhospital resourcesavailableworldwide,thisoptimalresourceinformationwillbeusedtodesignatelevelsofacutecaresurgeryhospitals(similartotraum acenters).Thisdesignation *Correspondence: Frederick.Moore@surgery.ufl.edu1AcuteCareSurgery,UniversityofFlorida,1600SouthwestArcherRoad, POBox100108,Gainesville,FL32610-0108,USA Fulllistofauthorinformationisavailableattheendofthearticle WORLD JOURNAL OF EMERGENCY SURGERY 2013Mooreetal.;licenseeBioMedCentralLtd.ThisisanOpenAccessarticledistributedunderthetermsoftheCreative CommonsAttributionLicense(http://creativecommons.org/licenses/by/2.0),whichpermitsunrestricteduse,distribution,and reproductioninanymedium,providedtheoriginalworkisproperlycited.TheCreativeCommonsPublicDomainDedication waiver(http://creativecommons.org/publicdomain/zero/1.0/)appliestothedatamadeavailableinthisarticle,unlessotherwise stated.Moore etal.WorldJournalofEmergencySurgery 2013, 8 :55 http://www.wjes.org/content/8/1/55

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processwillbeusedtoleveragehospitalstoupgradetheir resourcestooptimizetheiremergencysurgerycapabilities.BackgroundandsignificancePathogenesisDiverticulardiseaseiscommonaffectingover50%ofmen andwomenolderthan65years.Diverticulitisisinflammationofthecolonthatoccursasaresultofperforationofa diverticulumalmostexclusivelyinthesigmoidcolonand incidenceisestimatedtobe3.4to4.5per100,000people peryear[3-6].Diverticulitisisknownasthe diseaseofthe industrialrevolution ,sincetherearenoreportsorpathologicspecimensdocumentingevidenceofdiverticulardiseasepriortothe1900s[7].Inthelate1800s,theprocess ofroller-millingwheatwasintroducedwhichremovestwo thirdsofthefibercontentofwheat.Coincidentwiththis implementation,diverticulosiswasobservedinthefirst decadeofthe1900s.Itisnowknownthatadietlowin fiberisacontributingfactorinthedevelopmentofdiverticulardisease[7-9].Inastudyofnearly48,000USmen,a low-fiberdietincreasedtheriskofsymptomaticdiverticulardiseasebytwo-tothreefoldovera4-yearperiod[10]. Inadditiontolowdietaryfiber,alterationsincolonicintraluminalpressureshavebeenshowninpatientswith diverticulardisease.Althoughrestingintraluminalpressuresbetweendiverticulardiseasepatientsandcontrols donotdiffersignificantly,higherpressureshavebeen demonstratedinsegmentsofcolonwithdiverticula[11]. Inaddition,laterstudiesindicateincreasedcolonicmotility,asassessedbythenumberandamplitudeofbowel wallcontractions,inthesigmoidcolonofpatientswithdiverticulardisease[12-14].Therefore,bothalow-fiberdiet andcolonicdysmotilityhavebeenimplicatedinthepathogenesisofdiverticulardisease.TreatmentoptionsThesearebaseduponthestageofdisease.Table1depicts ascoringsystemthatsubdividesdiverticulitisbasedupon theextentofdiseaseidentifiedoncomputerizedtomography(CT)scanning.ThetraditionalHincheyclassificationwasdevelopedbeforeroutineCTscanning[15]and wehavemodifieditslightlytoreflectcontemporarymanagementdecisionsthatarebasedonCTscanfindings. MostcliniciansarecomfortabletreatingpatientsstageIA andIBdiverticulitiswithintravenous(IV)antibioticsand bowelrest.Theywillalsoreadilyoptforinterventional radiologypercutaneousdrainage( PCD )inpatientswith stageIIBdiseaseaslongasthepatientsdonothavesevere sepsis/septicshock(SS/SS).However,thereisconsiderable controversyoverwhatisthebestoptionforpatientswho presentwithstageIIIandIVdiverticulitiswhohavesigns ofSS/SS.Thetreatmentoptionsforthesepatientsaredescribedbelow:ThreestageprocedureWhilediverticulosiswasinitiallyregardedasapathologic curiosity,thefirstcolonresectionforperforateddiverticulitiswasreportedbyMayoin1907[16].However,asubsequentreportfromtheMayoclinicin1924,concludedthat acuteresectionaccentuatedtheinfectionresultingina prohibitedhighmortality[17].Theyrecommendedacolostomywithdistalirrigationandthendelayedresection whenthepatientconditionimproved.Overthenext20 years,avarietyofprocedureswereperformedforperforateddiverticulitis.In1942theMassachusettsGeneral Hospitalreportedtheirexperiencewiththesedifferent proceduresandconcludedthatthebestoutcomeswere achievedwithproximaldivertingcolostomyandthenresectionofthediseasedcoloninthreetosixmonthsafter theinflammationhadresolved[18].Thereafterthethree stageprocedurebecamethestandardofcare:1st-diverting transversecolostomyanddrainage;2nd-definitiveresectionandcolostomyafterthreetosixmonthsand3rdcolostomyclosureafterthreetosixmonths.TwostageprocedureAftertheintroductionofperioperativeantibioticsandimprovedperioperativecare,caseseriesemergedstartingin thelate1950sthatdemonstratedthatinselectcircumstancesthediseasedcoloncouldbesafelyresectedat the1stoperation.Thetwostageprocedure:1st-segmental sigmoidresectionwithendcolostomy[i.e.theHartmann ’ s procedure( HP )originallydescribedHenriHartmann in1921fortreatmentofcolorectalcancer][19]and2ndcolostomyclosureafterthreetosixmonthswasincreasinglypracticedandbecamestandardofcarebythe1980s. Thisapproachwassupportedbyastudypublishedin 1984whichcombinedpatientdatafrom36caseseries publishedsincethelate1950s[20].Thestudyincludea totalof821casesofdiverticulitiswithpurulent(i.e.stage IIIdisease)orfeculent(i.e.stageIVdisease)peritonitisof which316patientsunderwenta HP (withamortalityof 12%)comparedtothe505patientswhounderwentdivertingcolostomywithnoresection(withamortalityof29%). Whiletheseretrospectivecaseseriessufferfromselection biasinthatthelesshealthypatientsweremorelikelyto undergoadivertingcolostomywithnoresection,thisreportestablishedthatasubstantialportionofpatientscan undergoanemergency HP withanacceptablemortality. Table1PerforatedsigmoiddiverticulitisscoreStageCTscanfindings IAPhelogmonwithnoabscess IBPhlegmonwithabscess 4cm IIPhlegmonwithabscess>4cm IIIPurulentpertonitis(noholeincolon) IVFeculentpertonitis(persistentholeincolon) Moore etal.WorldJournalofEmergencySurgery 2013, 8 :55Page2of11 http://www.wjes.org/content/8/1/55

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Additionally,acuteresectionavoidedmissingacoloncancer(whichoccursinupto3%ofcases)anddecreased morbiditybecauseupto20%ofthenon-resectedpatients developedafistula.Interestingly,thereweretwosubsequentprospectiverandomizedtrials(PRTs)thatshowed divergentresults.InasinglecenterSwedishPRT,of46patientswithstageIIIpurulentperitonitis,25patientswho underwenta HP (with24%mortality)comparedto21patientswhounderwentcolostomywithnoresection(with 0%mortality)[21].InamulticenterFrenchPRTof103patientswithpurulentorfeculentperitonitis,55patients underwenta HP andhada<2%rateofpost-operative sepsiswithamortalityof23%[22].Incontrast,48patients underwentdivertingcolostomywithnoresection(with sutureclosureoftheholeinthestageIVcases)hada20% rateofpost-operativesepsiswithasimilarmortalityof 18%.Asaresultoftheseandotherdata,thecolorectal surgicalspecialistspublishedanEBGin2000inwhich theyconcludedthattheprocedureofchoiceforperforated diverticulitiswasa HP [23].However,withtherecognition uptohalfofthepatientswhounderwenta HP neverhad theircolostomyreversedandthatcolostomyclosurewasa morbidprocedure,manycolorectalsurgeonsperformeda primaryanastomosisinselectcases.Primaryresectionwithanastomosis(PRA)A2006meta-analysis[thatincluded15caseseries(13 retrospective)]indicatedthatmortalitywassignificantly lowerandtherewasatrendtowardsfewersurgicalcomplicationsinpatientswhounderwent PRA withorwithout aproximaldivertingloopileostomycomparedthosewho underwenta HP forperforateddiverticulitis[24].Again, whilethisreviewsuffersfromaselectionbiaswherethe lesshealthypatientsweremorelikelytoundergoaHP,it doesdocumentthatemergency PRA inselectpatientshas alowanastomoticleakrate(~6%)andthatinthesicker patients(stage>IIsubset) PRA and HP hadequivalent mortality(14.0vs.14.4%).Additionally,itwasrecognized that85%ofpatientswith PRA andproximalloopileostomyhadsubsequentstomalclosure[25].Asaresultof thesedata,thecolorectalsurgicalspecialistsupdatedtheir EBGin2006andrecommendedemergentdefinitivesigmoidresectionforperforateddiverticulitiswithperitonitis butconcludedthatanacceptablealternativetothe HP (i.e.colostomy)isprimaryanastomosis[26].Theprecise roleofproximalileostomydiversionafter PRA remains unsettled.Laparoscopiclavageanddrainage(LLD)Interestingly,asthecolorectalsurgicalspecialistsprogressivelyendorsedamoreaggressiveapproach,startingin 1996,therehavebeen18caseseriesinvolving806patients thatdocumentsurprisinglybetteroutcomeswithsimple LLD [27,28].In2008Myersetal.reportedthelargestseries todatewithcompellingresults(Figure1)[29].Outof1257 patientsadmittedfordiverticulitisoversevenyears,100 (7%)hadperitonitiswithevidenceoffreeaironx-rayor CTscan.Thesepatientswereresuscitated,givenathird generationcephalosporinandflagylandthentakenemergentlytotheORforlaparoscopy.Eightwerefoundtohave stageIVdiseaseandunderwenta HP .Theremaining92 patientsunderwent LLD .Three(3%)ofthesepatientsdied (whichmuchlowerthanreportedfor PRA or HP ).An additionaltwopatientshadnon-resolution,onerequired an HP ,andtheotherhadfurther PCD .Overall,88ofthe 92 LLD patientshadresolutionoftheirsymptoms.They weredischargedtohomeanddidnotundergoanelective resection.Overtheensuing36months,therewereonly tworecurrences.AnotherrecentstudybyLiangetal.associatessupports LLD [30].Theyreviewed88casesofdiverticulitis(predominantlystageIII)treatedlaparoscopically ofwhich47weretreatedby LLD and41bylaparoscopic HP (seeTable2)[30].Again LLD appearedeffectivefor sourcecontrolandhadbetteroutcomethanalaparoscopic HP .Interesting,theytreated5casesofstageIVdisease with LLD combinedwithlaparoscopicclosureofthesigmoidcolonperforation.MostrecentlytheDutchhave reviewedtheirexperiencewith LLD in38patientsandreportednotablylessimpressiveoutcomes[28].In31patientsthe LLD controlledthesepsis.Thesepatientshad lowmortality(1died),acceptablemorbidityandrelatively rapidrecovers.However,intheremaining7patients LLD didnotcontrolabdominalsepsis,twodiedofmultiple organfailure(MOF)and5requiredfurthersurgicalinterventions(3 HP s,1divertingstomaand1perforationclosure).Oneofthesediedfromaspirationandtheremaining fourexperiencedprolongedcomplicatedrecoveries.These authorsconcludedthatpatientselectionisofutmostimportance.TheybelieveitiscontraindicatedinstageIV disease.AdditionallytheynotedthatpatientswithstageIII diseasewhohavemultipleco-morbidities,immunosuppression,ahighCreactiveproteinleveland/orahigh MannheimPeritonitisIndexareathighriskoffailureand concludedthata HP asafirststepisthebestoptionin thesepatients.Nonoperativemanagement(NOM)Morerecently,Costietal.addedmorecontroversyto managementoptionswhentheyreportedtheirexperience with NOM of39hemodynamicallystablepatientswith stageIIIdiverticulitis[31].Three(8%)requiredanemergencyoperationbecauseofclinicaldeteriorationandunderwentan HP .Seven(18%)requiredlaterCT-guided PCD ofabscesses,whileamazingly29(74%)requiredno earlyoperativeinterventionandhospitalmortalitywas zero.Halfofthedischargedpatientsunderwentadelayed electivesigmoidresectionandoftheremaininghalf,five hadrecurrentdiverticulitissuccessfullytreatedmedicallyMoore etal.WorldJournalofEmergencySurgery 2013, 8 :55Page3of11 http://www.wjes.org/content/8/1/55

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(withlaterelectiveresection).Ofnote,patientswho underwentdelayedelectiveresectionexperiencedhigher thanexpectedmorbidityleadingtheauthorstoconclude thatperhapsdelayedresectionisnotnecessaryandcauses moreharmthangood.Itissurmisedwithresolutionofan acuteperforation;localfibrosispreventstherecurrentperforationofthediverticulum.DrCostihascautionedthatit isimperativetodifferentiatestageIIIfromstageIVdisease.TheyaccomplishthisbyusingaCTscanprotocol thatutilizesrectalcontrastandiftheanyextravasationis seen,thepatientisnotacandidatefor NOM .StagedlaparotomyTheconceptofa plannedrelaparotomy forfulminant peritonitishasbeendebatedforoverthirtyyears.Reoperationsareperformedevery48hoursfor “ washouts ” untiltheabdomenisfreeofongoingperitonitisandthen theabdomenisclosed.Thissupposedlypreventsand/or providesearlytreatmentforsecondaryinfectionsthus decreasinglateMOFanddeaths.Thedownsideofthe plannedrelaparotomy approachisincreasedresource utilizationandtheincreasedpotentialriskforgastrointestinalfistulasanddelayedhernias.Thealternativeis referredtoas relaparotomyon-demand whererelaparotomyisperformedforclinicaldeteriorationorlackofimprovement.Thepotentialdownsidetothisapproachis harmfuldelaysindiagnosingsecondaryabdominalinfectionsandthepresenceofmoredenseadhesionsifthere isaneedtore-operate.Overtheyearstherehavebeen eightcaseseriesthathaveofferedconflictingresultsregardingtheimpactofthesestrategiesonoutcome.A meta-analysisofthesedataconcluded relaparotomyondemand wasthepreferredapproachinpatientswith APACHEII<10[32].Furthermore,arecentPRTbyvan Ruleret.al.inpatientswithAPACHEII>10indicates thatthepracticeof plannedrelaparotomy offeredno clinicaladvantageover relaparotomyon-demand and wasassociatedwithsubstantialincreasesinexpenditure ofhospitalresources[33].Damagecontrollaparotomy(DCL)Intheearly1980 ’ straumasurgeonsrecognizedwhenthey operatedinthesettingofthe “ bloodyviscouscycle ” of acidosis,hypothermiaandcoagulopathy,operatingroom (OR)mortalityfrombleedingwasunacceptablyhigh[34]. Thispromptedthedevelopoftheconceptofanabbreviatedlaparotomyusinggauzepackingtostopbleeding combinedtemporaryabdominalclosure( TAC )andtriage totheICUwiththeintentofoptimizingphysiology[35]. ThepatientistakenbacktotheORafter24 – 48hoursfor definitivetreatmentofinjuriesandabdominalclosure. Thisconceptwasinitiallypromotedformajorliverinjuriesasawaytoavoidmajorliverresectionsbutwas soonextendedtoallemergencytraumalaparotomies[36]. Overthenextdecadethisconceptevolvedinto “ damage control ” whichwasamajorparadigmshiftfortrauma Figure1 Experiencewithlaporoscopiclavageanddrainage. Table2Laparoscopiclavageanddrainage(LLD) comparedtolaparoscopichatman ’ sprocedure(LHP)LLDLHPpvalue #ofpatient4741 ORtime(minutes)10040182550.001 Conversion2%15%0.05 Complications4%13%0.05 Mortality0%2.4%ns Hospitalstay(days)6.62.416.6100.01 Colostomyclosurena72%na Electiveresection45%nana Moore etal.WorldJournalofEmergencySurgery 2013, 8 :55Page4of11 http://www.wjes.org/content/8/1/55

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surgeons[37-39].Thispracticebecamestandardofcare worldwidebythemid-1990sandhassavedthelivesof manypatientswhopreviouslyexsanguinatedontheOR table.However,theroleof DCL inemergencygeneral surgeryiscontroversial[40-43].Itisoftenconfusedwith theconceptofa plannedrelaparotomy (describedabove). Mooreetal.proposedthatthepurposeof DCL inintraabdominalsepsisisdifferentfromtrauma.Whilethe “ bloodyviscouscycle ” canoccurwithintra-abdominal sepsis,exsanguinationisuncommonshortoftechnical mishaps.Ratherpatientswithintra-abdominalsepsiscan presentinpersistentsepticshock[40].Initially,theyare toounstabletoundergoimmediateoperation.Animmediateoperationinthesepatientsresultsinahighriskfor postoperativeacutekidneyinjury(AKI)setsthestagefor MOF,prolongedintensivecareunit(ICU)staysand dismallong-termoutcomes[40,44,45].Bytheirprotocol, patientpresentinginsepticshockwarrantpre-operative optimizationwithearlygoaldirectedtherapy.Iftheyare notoptimizedpre-operatively,theywillexperienceprofoundhypotensionwhensubjectedtogeneralanesthesia andrequirehighdosesvasopressors(typicallybolusesof phenylephrine)tomaintainmeanarterialpressure(MAP) andiftheyundergoatraditional HP thiswillbeprolonged andcontributesubstantiallytopost-operativeAKI[45]. Afteroptimization(describedbelow),thepatientistaken totheOR.Afterundergoinggeneralanesthesia,thesurgeonassesseswhetherthepatientisstillinsepticshock.If so,theORteamisinformedthata DCL isgoingtobeperformed.Theyshouldanticipateashortoperation(roughly 30 – 45minutes)andgetthesuppliesnecessaryfor a TAC .Alimitedcolonresectionoftheinflamedperforatedcolonisperformedusingstaplers(referredtoasa “ perforection ” )withnocolostomyanda TAC isperformed usinga “ vacpack ” technique.Thepatientisreturnedto theICUforongoingresuscitation.Oncephysiologicabnormalitiesarecorrected,thepatientisreturnedtothe ORforperitoneallavageandcolostomyformation.Adefinitiveresectionshouldbedoneiffeasibleforpatients whohaveundergonealimitedresectionattheprevious DCL topreventafistulaandrecurrence.However,KafkaRitschetal.proposeanalternativereasontoperform DCL inpatientswithdiverticulitisistoavoidacolostomyby performingadelayedanastomosis[43].Inaprospective study51patientswithperforateddiverticulitis(stageIII/ IV)wereinitiallymanagedwithlimitedresection,lavage and TAC withavacuum-assistedclosuredevicefollowed bysecond,reconstructiveoperation24 – 48hourslatersupervisedbyacolorectalsurgicalspecialist.Bowelcontinuitywasrestoredin38(84%)patients,ofwhichfourwere protectedbyaloopileostomy.Fiveanastomoticleaks (13%)wereencounteredrequiringloopileostomyintwo patientsor HP inthreepatients.Postoperativeabscesses wereseeninfourpatients,abdominalwalldehiscencein oneandrelaparotomyfordrain-relatedsmallbowel perforationinone.Theoverallmortalityratewas10% and35/46(76%)ofthesurvivingpatientsleftthehospital withreconstructedcoloncontinuity.Fascialclosurewas achievedinallpatients.SummaryOverthelastcentury,basedprimarilyonretrospective caseseries,wehaveseenaprogressioninthetreatmentof perforateddiverticulitisfromaconservative3stageprocedureinthe1940stothe2stage HP inthe1980s(which ispracticedbymanysurgeonstoday)andmostrecently anaggressiveonestage PRA thatisbeingpromotedby colorectalsurgicalspecialists.However,nowthereisemergingevidencethatweshouldadoptaminimaliststrategy of LLD or NOM inthelesssickpatientswhileemploying DCL inthesickestpatients.Unfortunately,likemostof theliteratureondiverticulitis,theserecentstudiesare retrospectiveandweareawaitingtheresultsofPRTsthat areongoinginEurope[46,47].Giventhislackofhigh gradedata,weproposeareasonabletreatmentalgorithm basedontheexpertopinionofsurgeonswhoactively practiceemergencysurgery[40,47-49].DecisionmakingalgorithmKeyQuestionsthatdrivedecisionmakinginclude: 1)Isclinicaldiagnosisconsistentwithperforated sigmoiddiverticulitis? 2)Doesthepatientrequireanemergencyoperation? 3)Isthepatientinsepticshockandshouldundergo pre-operativeoptimization? 4)Isthepatientinsepticshockandshouldundergo damagecontrollaparotomy? 5)Shouldthepatientundergolaparoscopiclavageand drainage? 6)Whatisadefinitiveresectionandshouldthepatient undergocolostomyoraprimaryanastomosis? 7)Shouldthepatientundergointerventionalradiologic percutaneousdrainage? 8)Shouldthepatientbeobservedandwhatconstitutes observationaltherapy? 9)Shouldpatientsundergodelayedcolonoscopyafter acutediverticulitistoruleoutcoloncancer? 10)Shouldpatientswithperforatedsigmoid diverticulitiswhorespondtoconservativetherapy undergodelayedelectivecolonresection? 11)ShouldpatientsafteraHartmann ’ sProcedurehavea colostomyclosureandwhatistheoptimaltime? Figure2depictsourproposedmanagementalgorithm foracutecomplicateddiverticulitis.Moore etal.WorldJournalofEmergencySurgery 2013, 8 :55Page5of11 http://www.wjes.org/content/8/1/55

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MakingtheclinicaldiagnosisWhenencounteringanewpatientintheemergencydepartment(ED),thesurgeonfirstmakestheclinicaldiagnosisofdiverticulitisbasedonhistory,physicalexam androutinelaboratorytesting.Abdominalpainisthe primarypresentingsymptom.Itistypicallylocatedin theleftlowerquadrant;however,aredundantsigmoid coloncanreachtherightlowerquadrantandmimicappendicitis.Localizedperitonealirritationcanresultin guardingandreboundtenderness.Freeperforationoften presentsasfrankperitonitis.Feverandleukocytosisare usuallypresentandassistinmakingtheclinicaldiagnosis.Nauseaandvomitingarethemostnotablesymptoms whenastrictureresultsinanobstruction.Theinitialassessmentshouldincludea)anassessmentoftheseverity ofthesignsofthesystemicinflammatoryresponsesyndrome(SIRS)includingheartrate,respiratoryrate,temperatureandwhitebloodcellcount,b)peritonitison physicalexamandc)signsoforgandysfunctions.Patientswithclinicaldiagnosisconsistentwithdiverticulitis whohaveconcerningsignsofsepsisshouldbeconsideredtobeathighriskforcomplicateddiverticulitis. TheyshouldhaveIVaccessobtained,begivenabolusof IVisotoniccrystalloids(20ml/kg),beadministeredIV antibiotics,andbeadmittedtothehospital. ThesepatientsshouldundergoCTscanningwithIV contrastoftheabdomenandpelviswiththeexception ofpregnantwomenwhereultrasoundisrecommended [50].CTscanninghasahighsensitivityandspecificityin confirmingthediagnosisandidentifyingpatientswho arecandidatesfortherapeutic PCD [51,52].CTscanning alsoexcludesothercausesofleftlowerquadrantabdominalpain(e.g.leakingabdominalaorticaneurismoran ovarianabscess),butisnotreliableindifferentiating acutediverticulitisfromcolonmalignancy[53].PatientswhorequireanemergencyoperationThisdecisionmostlypertainstopatientswithstageIII andstageIVdiverticulitiswhopresentwithsignsofsepsis andneedanemergencyoperationforsourcecontrol.The timingandtypeofsourcecontrolisunclear.Traditionally, allofthesepatientsweretakenexpedientlytotheOR. However,therehasbeenashiftinthisparadigmwiththe recognitionthatoperatinginthesettingofsepticshock setsthestageforpostoperativeAKI,MOF,prolongedICU staysanddismallong-termoutcomes[40,44,45].Specifically,webelievepatientsinsepticshockbenefitfrom pre-operativeoptimization .Thistakes2 – 3hours[54,55]. ItstartswithobtainingtwolargeboreIVlinesthrough whichbroadspectrumantibioticsandabolusofisotonic crystalloids(20ml/kg)areadministered.Acentralline(via theinternaljugularveinplacedunderultrasoundguidance)andanarteriallineareconcurrentlyplaced.With ongoingvolumeloading,CVPisincreasedtoabove10 cmH2O.Atthispointthepatientisintubatedandventilationoptimized.Norepinephrineistitratedtomaintain MAP>65mmHgandifhighdosesarerequired,stress dosesteroidsandlowdosevasopressinareadministered. Electrolyteabnormalitiesarecorrectedandbloodproductsareadministeredbasedoninstitutionalguidelines. Lactateandmixedvenoushemoglobinsaturationsare measuredandtrendedtoassesstheadequacyoftheresuscitativeefforts.OncethepatientisstableenoughtotolerateORtransportandgeneralanesthesia,he/sheshould betransportedtotheORforasourcecontroloperation. AfterthepatientisintheORandundergeneralanesthesia,thesurgeonneedstoreassesswhetherthepatient isstillinsepticshock.Ifso,theORteamshouldbeinformedthata DCL isgoingtobeperformed(described above).Theyshouldanticipateashortoperation(roughly 30 – 45minutes)andgetthesuppliesnecessaryfora TAC Figure2 Decisionmakingalgorithmforperforatedsigmoiddiverticulitis. Moore etal.WorldJournalofEmergencySurgery 2013, 8 :55Page6of11 http://www.wjes.org/content/8/1/55

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Whiletheroleof DCL inthissettingiscontroversial,it shouldnotbeconfusedwiththeconceptofa planned relaparotomy (describedabove)[32].Atthesecondoperation,webelievethatthedecisiontoperformadelayed anastomosisshouldbeindividualizedbasedonthecurrent physiology,theconditionofbowel,patientco-morbidities, andsurgeonexperience.However,inmostpatientswho haveundergone DCL becauseofpersistentsepticshock, bowelwalledemaandpersistenthypoperfusionmakea delayedanastomosisanunsafeoption. ForpatientswhohavestageIIIandstageIVdiseaseand concerningsignsofsepsisbutarenotinsepticshockalso needsourcecontrol.Whiletraditionallythesepatients weretakenexpeditiouslytotheORfora HP ora PRA ,we believethattherecentcaseseriesindicatethat LLD isa viableoptionthatshouldbeemployedtolowriskpatients butrecommendadefinitivesigmoidresectionforhighrisk thatincludepatientswhoarea)immunocompromised, b)havesevereco-morbiditiesc)organdysfunctionsattributabletoongoingsepsisord)stageIVdisease.Theagain thedecisiontoperformananastomosisshouldbeindividualizedbasedonthecurrentphysiology,theconditionof bowel,patientco-morbidities,andsurgeonexperience.PatientswhodonotrequireanemergencyoperationInitialrecommendedtreatmentofstageIAandIBdiverticulitisincludesa)nilperos(NPO),b)nasogastrictube totreat(ifpresent)symptomsofnausea,vomitingandabdominaldistentionandc)antibioticswithactivityagainst commongram-negativeandanaerobicpathogens.Anumberofsingleagentsandcombinationregimensprovide suchactivity.However,thereislittleevidenceonwhichto baseselectionofspecificantimicrobialregimens,andno regimenhasdemonstratedsuperiority[56,57].Ingeneral, episodesofdiverticulitissevereenoughtowarranthospitalizationshouldbeinitiallymanagedwithIVantibiotics. Oralantibiotictherapycanbestartedwhenthepatient's conditionimprovesandcontinuedasoutpatienttreatment.Thereisapaucityofdataregardingtheoptimal durationofantimicrobialtherapy. PatientswithstageIIdiverticulitisshouldbemanagedas abovebutshouldalsobeevaluatedbyinterventionalradiologyforCTguided PCD [51].Thepreferredapproachis trans-abdominaleitheranteriororlateral,attemptingto avoidtheinferiorepigastricordeepcircumflexiliacvessels.Otherapproachesincludetransgluteal,transperineal, transvaginalortransanal.ReportedfailureratesforPCD rangefrom15%to30%withacomplicationrateof5%(includingbleeding,perforationofahollowviscousorfistula formation)[58-60].ObservationPatientswithstageIA,IBandIIdiverticulitisshouldbe treatedasdescribedaboveandobservedwithserial a)physicalexams,b)assessmentsofSIRSseverityand c)laboratoryevidenceorgandysfunctions.Itisexpected thattheirclinicalconditionwillimproveover72hours. Ifitdoesnotimproveortheirconditionworsensthey shouldundergoanurgentoperation.Patientswhoresolvetheirsymptomsshouldbedischargedtohomeon oralantibioticswithfollow-up(describedbelow).PatientswhofailobservationThesepatientsshouldundergodefinitivesigmoidresection.Whilelaparoscopiccolonresectioncomparedto openlaparotomycolonresectionisassociatedwithbetter outcomesinelectivesurgery[61,62],thereisnoevidence thatthesameistrueinurgent/emergentoperations.Definitivesigmoidresectionrequiresmobilizationofthe sigmoidcolonwithavoidanceofinjurytotheureters.Ureteralstentsshouldbeusedselectivelyinthosepatients withabscessesorexcessiveinflammationinthepelvis.For definitiveresectionthedistalmarginofresectionshould betheupperrectum[63]whiletheproximalmarginofresectionshouldgobacktonon-inflameddescendingcolon. Alldiverticulidonotneedtoberesected.Thesplenicflexureisgenerallynotmobilizedunlessneededtoformcolostomywhenindicated.Aspreviouslydiscussed,themajor debateiswhethertoperforma PRA ora HP .Avarietyof factorsneedtobeconsideredincludinga)diseaseseverity b)conditionofbowelatthesiteofanastomosis,c)patient physiology,d)nutritionalstatus,e)patientco-morbidities, f)hospital/situationalfactorsandg)surgeonexperience. Anotherunresolveddebateisshouldaprotectingdiverting ileostomybeaddedifa PRA isperformed?Unlessconditionsareoptimal,thisistheprudentoption.Theuseof perioperativecoloniclavageappearstolowercomplicationswith PRA ,butthesupportingevidenceislimited [64].Omentoplastydoesnotofferanybenefits[65].The inferiormesentericarteryshouldbepreservedwhenfeasibletolowertheriskofananastomoticleak[66].Dischargeandfollow-upAlthoughthereislackofevidencethatlifestylechanges willhelppreventrecurrentdiverticulitis,itislikelythat measuresthoughttopreventaninitialepisodeofdiverticulitiswouldalsoapplytopreventingarecurrence. Thesehealthylifestylesshouldberecommendedupondischargeandincludea)physicalexercise,b)ahighfiberdiet, c)reducedredmeat,d)minimizealcoholconsumption ande)stopsmoking[67,68].Patientsshouldreturntothe clinicifsymptomsrecurandhaveafollow-upclinicappointmentatfourtosixweekstoaddressthreeissues.ColonoscopyAftertheinflammationfromanewonsetofdiverticulitis hasresolved,traditionallypatientshaveundergonecolonoscopytoruleoutcoloncancer.However,theneedforMoore etal.WorldJournalofEmergencySurgery 2013, 8 :55Page7of11 http://www.wjes.org/content/8/1/55

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routinecolonoscopyhasrecentlybeenquestioned[69]. Colonoscopyisatime-consumingandaresourceburden onanalready-stretchedhealthcaresystem.Inaddition, endoscopymaybetechnicallymoredifficultinthesepatientswithanriskiatrogenicbowelperforation(~0.1%). ThereportedincidenceofcoloncancerinCTdiagnosed acutediverticulitisrangesfrom0.5to3%.ButwithtechnologicalimprovementinqualityandresolutionofCT hasledtobetterevaluationofthecolonintheaffected segmentandthechancesofmissingacoloncancerhas decreased.ArecentstudybySallinenetal.provides additionalinsightintothisdebate[70].Theylooked536 patientswereadmittedtothehospitalfordiverticulitis whoweretreatedwithoutanoperation.Ofthesepatients 394underwentadelayedcolonoscopyand17(2.7%)were foundtohavecancer.Sixteencancercases(94%)hadabscessintheCT,whereastheremainingcasehadpericolic extraluminalair,butnoabscess.Ofthepatientswithabscess,11%hadcancermimickingacutediverticulitis.No cancerwasfoundinpatientswithuncomplicateddiverticulitis.Besidesabscess,otherindependentriskfactorsfor cancerincludedsuspicionofcancerbyaradiologist,thicknessofbowelwallover15mm,nodiverticulaseen,and previouslyundiagnosedmetastases.Theyconcludethat routinecolonoscopyafterCT-provenuncomplicateddiverticulitisseemsunnecessary.However,colonoscopyshould beperformedinpatientsdiagnosedwithadiverticularabscessorthosewithoneoftheindependentriskfactors. BariumenemaorCTcolonographycanbeusedincases whereacompletecolonoscopycannotbeaccomplished.ProphylacticsigmoidcolectomyIntherecentpast,adelayedelectivesigmoidresection wasrecommendedaftertwocasesofuncomplicatedor onecaseofcomplicatedacutediverticulitis[23].The ideawasthattheelectiveresectionwouldbelessmorbid thanarecurrentboutofdiverticulitis.However,anelectiveresectionhasrisksincludinga)upto10%recurrence, b)1-2%mortalityandc)a10%needforastoma.Additionally,itisnowapparentthatthemajorityofpatients withseverediverticulitispresentattheir1stepisodeand thatrecurrentdiverticulitisisrelativelyrare(roughly2% peryear).Additionally,whenitrecursitislesslikelyto requireanoperationandhasaverylowmortality.Asa resulttheindicationsforelectiveresectionafteracute diverticulitishavechangedsubstantially[67,68,71-74]. Thefollowingisarecommendedlist: a)aElectiveresectionshouldbedoneafterone documentedepisodeacutediverticulitisinpatients withoneormoreofthefollowingriskfactors includingimmunosuppression,chronicuseof steroids,chronicrenalfailure,diabetesmellitus, COPD,orcollagenvasculardisease. b)Forpatientswithouttheaboveriskfactors,the preferredtimingofelectivesurgeryisafterthe3rdor 4thepisodeofuncomplicateddiverticulitis. c)Patientswithoneepisodeofcomplicated diverticulitiswithpersistentorrecurrentsymptoms. d)Patientswithcomplicateddiverticulitiswhohavean anatomicdeformityincludingastrictureorfistula. Thetimingofthiselectivecolectomyisdebatedbut generallyonewaits4 – 6weekstoallowtheinflammation tosubside[75,76].Laparoscopiccolectomyispreferred opencolectomy[61,62].ColostomyclosureForpatientswhohaveundergonea HP ,colostomyclosure isperformedinonlyabouthalfofthepatients[25,77]. Manyofthepatientsareelderlywithmultipleriskfactors thatcontraindicateasecondsurgicalprocedure.Additionally,colostomyclosurecarriessignificantriskofperioperativecomplications(10to40%)[78].Patientswhoare satisfiedwithlivingwithacolostomymaynotwantassumetheserisksaswellasthetimeandtheexpenseofa secondoperation.Theoptimaltimingcolostomyclosureit notclear[79,80].Itshouldnotbeperformeduntilthepatienthasresolvedtheiracutephaseresponseandresolved nutritionaldeficienciestooptimizewoundhealingreducingtheriskofanastomoticleakandwoundinfection. Thisusuallytakesthreetosixmonthsbutsometimesup toayearornever.Itdependsofthepatient ’ sage,comorbiditiesandhowdeconditionedtheywereatthetime ofhospitaldischarge.Recentstudieshavedocumentedthat thelong-termoutcomesofelderlypatientsafterbeinghospitalizedforsepsisisnotablypoor[81,82].ConclusionBasedonavailableclinicaldataandourcollectiveexpert opinions,weproposeamanagementstrategythatwefeel isrationalandsafe.AllpatientswithpresumedcomplicateddiverticulitisshouldundergoCTscanningwithIV contrast.Thiswillconfirmtheclinicaldiagnosisandallow stagingofthedisease.Therapeuticdecisioninthebased ona)stageofdisease,b)patientco-morbidityandc)sepsis severity.PatientswithstageI/IIdiseasegenerallydonot presentwithseveresepsis/septicshock(SS/SS)andcanbe safelytreatedwithbowelrest,IVantibioticsand PDC of largerabscesses.IfstageI/IIthefail NOM orprogress intoSS/SStheyshouldundergo PRA or HP dependinga varietyfactorsoutlinedabove.PatientswithstageIII/IV diseasemaypresentinsepticshock.Ifsotheyshould undergopre-operativeoptimizationandifsepticshock persistsonceintheoperatingroom(OR),theyshould undergo DCL withalimitedresection.Ifconditionsare optimalat2ndORadelayed PRA shouldbeperformed.If conditionareunfavorable,and HP shouldbedone.IfMoore etal.WorldJournalofEmergencySurgery 2013, 8 :55Page8of11 http://www.wjes.org/content/8/1/55

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patientsstageIII/IVdonotpresentinsepticshockthey shouldbetakentotheORandu ndergolaparoscopy.Low riskpatientsshouldundergo LLD whilehighriskpatients [i.e.a)immunocompromised,b)havesevereco-morbidities c)organdysfunctionsattri butabletoongoingsepsisor d)stageIVdisease]shouldundergo PRA or HP depending avarietyfactorsoutlinedabov e.Proximaldivertingileostomyshouldbeusedliberallywith PRA .Abbreviations CT: Computerizedtomographic;CVP:Centralvenouspressure; ED:Emergencyroom;EBG:Evidencebasedguideline;DCL:Damagecontrol laparotomy;HP:Hartmann ’ sprocedure;IV:Intravenous;LLD:Laparoscopic lavageanddrainage;MAP:Meanarterialpressure;MOF:Multipleorgan failure;NOM:Nonoperativemanagement;OR:Operatingroom; PCD:Percutaneousdrainage;PRA:Primaryresectionanastomosis; PRTs:Prospectiverandomizedtrials;SS/SS:Severesepsis/septicshock; TAC:Temporaryabdominalclosure. Competinginterests Theauthorshavenocompetinginterestsandnothingtodisclose. Authors ’ contributions Alloftheauthors(FMFC,EM,AL,andAP)havea)madesubstantial contributionstoconceptionanddesignofthispositionpaper, b)beeninvolvedinacquisitionofrelevantreferencesandtheir interpretation;c)beeninvolvedindraftingthemanuscriptorrevisingit criticallyforimportantintellectualcontent;d)givenfinalapprovalofthe versiontobepublished;ande)agreetobeaccountableforallaspectsof theworkinensuringthatquestionsrelatedtotheaccuracyorintegrityof anypartoftheworkareappropriatelyinvestigatedandresolved.Allauthors readandapprovedthefinalmanuscript. Authordetails1AcuteCareSurgery,UniversityofFlorida,1600SouthwestArcherRoad, POBox100108,Gainesville,FL32610-0108,USA.2EmergencySurgery Department,ParmaUniversityHospital,ViaCracvia23,Bologna40139, Italy.3UniversityofColoradoHealthScienceCenter,DenverHealthScience Center,777BannockStreet,Denver,CO80204-4507,USA.4Departmentof AbdominalSurgery,UniversityofHelsinki,Haartmaninkatu4,POBox340, MeilahiHospital,FIN-00029HUS,Helsinki,HUS00290,Finland.5University ofPittsburgh,F-1281,UPMC-Presbyterian,Pittsburgh,PA15213,USA. Received:25November2013Accepted:26November2013 Published:26December2013 References1.ShafiS,AboutanosMB,AgarwalSJr,BrownCV,CrandallM,FelicianoDV, GuillamondeguiO,HaiderA,InabaK,OslerTM,RossS,RozyckiGS, TominagaGT,AssessmentACS,PatientO: Emergencygeneralsurgery: definitionandestimatedburdenofdisease. 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Submit your next manuscript to BioMed Central and take full advantage of: € Convenient online submission € Thorough peer review € No space constraints or color “gure charges € Immediate publication on acceptance € Inclusion in PubMed, CAS, Scopus and Google Scholar € Research which is freely available for redistribution Submit your manuscript at www.biomedcentral.com/submit Moore etal.WorldJournalofEmergencySurgery 2013, 8 :55Page11of11 http://www.wjes.org/content/8/1/55