醫(yī)學教學課件：Disturbance of Circulation Series -Shock

DisturbanceofCirculationSeries-ShockOutlineDefinitionEpidemiologyPhysiologyClassesofShockClinicalPresentationManagementControversiesDefinitionAphysiologicstatecharacterizedbyInadequatetissueperfusionClinicallymanifestedbyHemodynamicdisturbancesOrgandysfunctionEpidemiologyMortalitySepticshock–35-40%(1monthmortality)Cardiogenicshock–60-90%Hypovolemicshock–variable/mechanismPathophysiologyImbalanceinoxygensupplyanddemandConversionfromaerobictoanaerobicmetabolismAppropriateandinappropriatemetabolicandphysiologicresponsesPathophysiologyCellularphysiologyCellmembraneionpumpdysfunctionLeakageofintracellularcontentsintotheextracellularspaceIntracellularpHdysregulationResultantsystemicphysiologyCelldeathandendorgandysfunctionMSOFanddeathPhysiologyCharacterizedbythreestagesPreshock(warmshock,compensatedshock)ShockEndorgandysfunctionPhysiologyCompensatedshockLowpreloadshock–tachycardia,vasoconstriction,mildlydecreasedBPLowafterload(distributive)shock–peripheralvasodilation,hyperdynamicstatePathophysiologyShockInitialsignsofendorgandysfunctionTachycardiaTachypneaMetabolicacidosisOliguriaCoolandclammyskinPhysiologyEndOrganDysfunctionProgressiveirreversibledysfunctionOliguriaoranuriaProgressiveacidosisanddecreasedCOAgitation,obtundation,andcomaPatientdeathClassificationSchemesaredesignedtosimplifycomplexphysiologyMajorclassesofshockHypovolemicCardiogenicDistributiveHypovolemicShockResultsfromdecreasedpreloadEtiologicclassesHemorrhage-e.g.trauma,GIbleed,rupturedaneurysmFluidloss-e.g.diarrhea,vomiting,burns,thirdspacing,iatrogenicHypovolemicShockHemorrhagicShockParameterIIIIIIIVBloodloss(ml)<750750–15001500–2000>2000Bloodloss(%)<15%15–30%30–40%>40%Pulserate(beats/min)<100>100>120>140BloodpressureNormalDecreasedDecreasedDecreasedRespiratoryrate(bpm)14–2020–3030–40>35Urineoutput(ml/hour)>3020–305–15NegligibleCNSsymptomsNormalAnxiousConfusedLethargicCritCare.2004;8(5):373–381.

CardiogenicShockResultsfrompumpfailureDecreasedsystolicfunctionResultantdecreasedcardiacoutputEtiologiccategoriesMyopathicArrhythmicMechanicalExtracardiac(obstructive)DistributiveShockResultsfromaseveredecreaseinSVRVasodilationreducesafterloadMaybeassociatedwithincreasedCOEtiologiccategoriesSepsisNeurogenic/spinalOther(nextpage)SVR:SystemicvascularresistanceDistributiveShockOthercausesSystemicinflammation–pancreatitis,burnsToxicshocksyndromeAnaphylaxisandanaphylactoidreactionsToxinreactions–drugs,transfusionsAddisoniancrisisMyxedemacomaDistributiveShockSepticShockSIRS:systemicinflammatoryresponsesyndromeClinicalPresentationClinicalpresentationvarieswithtypeandcause,buttherearefeaturesincommonHypotension(SBP<90orDelta>40)Cool,clammyskin(exceptions–earlydistributive,terminalshock)OliguriaChangeinmentalstatusMetabolicacidosisEvaluationDoneinparallelwithtreatment!H&P–helpfultodistinguishtypeofshockFulllaboratoryevaluation(includingH&H,cardiacenzymes,ABG)Basicstudies–CxR,EKG,UABasicmonitoring–VS,UOP,CVP,A-lineImagingifappropriate–FAST,CTEchovs.PAcatheterizationCO,PAS/PAD/PAW,SVR,SvO2TreatmentManagetheemergencyDeterminetheunderlyingcauseDefinitivemanagementorsupportManagetheEmergencyYourpatientisinextremis–tachycardic,hypotensive,obtundedHowlongdoyouhavetomanagethis?SuggeststhatmanythingsmustbedoneatonceDrawinancillarystaffforsupport!Whatmustbedone?ManagetheEmergencyOnepersonrunsthecode!ControlairwayandbreathingMaximizeoxygendeliveryPlacelines,tubes,andmonitorsGetandrunIVFonapressurebagGetandrunblood(ifappropriate)GetandhangpressorsCallyoursenior/fellow/attendingDeterminetheCauseOftenobviousbasedonhistoryTraumamostoftenhypovolemic(hemorrhagic)Postoperativemostoftenhypovolemic(hemorrhagicorthirdspacing)DebilitatedhospitalizedptsmostoftensepticMustevaluateallptsforriskfactorsforMIandconsidercardiogenicConsiderdistributive(spinal)shockintraumaDeterminetheCauseWhatifyou’rewrong?85y/oM4hourspostopS/Psigmoidresectionforperforateddiverticulitisishypotensiveonamonitoredbedat70/40LikelycausesBestactionsforthefirst5minutes?DefinitiveManagementHypovolemic–Fluidresuscitate(bloodorcrystalloid)andcontrolongoinglossCardiogenic-Restorebloodpressure(chemicalandmechanical)andpreventongoingcardiacdeathDistributive–Fluidresuscitate,pressorsformaintenance,immediateabx/surgicalcontrolforinfection,steroidsforadrenocorticalinsufficiencyControversiesIVFResuscitationLimitedresuscitation