《外科急诊创伤(英文)-休克及出血课件》由会员分享，可在线阅读，更多相关《外科急诊创伤(英文)-休克及出血课件（117页珍藏版）》请在金锄头文库上搜索。
1、Hemorrhage & ShockSections Introduction to Hemorrhage & ShockHemorrhageShockHemorrhageAbnormal internal or external loss of bloodHomeostasisTendency of the body to maintain a steady and normal internal environmentShockINADEQUATE TISSUE PERFUSIONTransition between homeostasis and deathIntroduction to
2、 Hemorrhage & Shock1800sInjury to one part of the body results in often fatal effectStrychnine to stimulate NS; seizuresElectrical currentalcohol“shock was not a process of dying, rather a marshaling of the bodily defenses in a struggle to live”Realized a fall in BP could account for all symptoms of
3、 shockRepresents a generalized failure of the body to deliver sufficient amounts of O2 to its tissuesS/S represent compensation measures utilized by the body to maintain delivery of O2 to vital organsDelay of appropriate therapy, cascade of events results in damage to organsTreatment GoalsRecognitio
4、n of early shockAppropriate airway managementRapid transportation to appropriate facilityHemorrhageCirculatory SystemHemorrhage ClassificationClottingFactors Affecting ClottingHemorrhage ControlStages of HemorrhageHemorrhage AssessmentHemorrhage ManagementCardiovascular SystemDelivery of nutrients a
5、nd O2 to tissues and cellsTransportation of waste products produced by metabolism to liver and kidneysDelivery of CO2 to lungsComponentsHeart or pumpBlood vessels or pipesBlood or fluidCirculatory SystemReview Review TerminologyTerminology Stroke VolumeStroke Volume PreloadPreload Ventricular Fillin
6、gVentricular Filling Frank-Starling Frank-Starling MechanismMechanism AfterloadAfterload Cardiac OutputCardiac OutputSVxHR=COSVxHR=CO5L/min5L/min Fick PrincipleFick PrincipleHeartHeart Parasympathetic Parasympathetic Nervous SystemNervous SystemSlows rateSlows rateVagus NerveVagus Nerve Sympathetic
7、Nervous Sympathetic Nervous SystemSystemIncreases rateIncreases rateCardiac PlexusCardiac PlexusCardiac OutputVolume of blood pumped in 1 minute = 4-6LSV x HRSV = amount of blood ejected from left ventricle with each contractionBlood PressureDirectly proportional to the product of the CO multiplied
8、by SVRBP = CO x SVRSVR, resistance to flow in the system (systemic vascular resistance)Stroke VolumePreloadRepresents filling of the ventricleVolume of blood delivered to atria prior to ventricular diastoleDependent on venous returnAfterloadAmount of resistance heart must overcome to eject bloodCont
9、ractilityAbility to contract, inotropyFrank Starlings LawInotropyNegativeScar tissue, CHFBeta adrenergic blockersCalcium channel blockersPositive Beta adrenergic agonists, B1List some B blockers, Ca channel blockers, B agonistsNamesIndicationsContraindicationsWhat would you expect to see if you admi
10、nistered this medication?Why?Fick PrincipleFactors necessary for systemic O2 deliveryAbility of O2 to diffuse across alveolar membrane into blood streamAdequate number of RBCs to transport O2Adequate blood flow to transport RBCsAbility of RBCs to off-load O2O2 DeliveryNormal circumstances body extra
11、cts about 20% of O2 and 80% returned to heart for reoxygenationNormal ratio of delivered to consumed 5:1Shock may increase extraction to 50%Ratio drops to 2:1Cellular MetabolismGlycolysisKrebs CycleElectron TransportGlycolysisOccurs in cytoplasmGlucose converted to pyruvic acid2 ATP createdO2 presen
12、t further aerobic metabolismNo O2 present, hypoperfusion, pyruvic acid converted to lactic acidLiver converts some lactic acidGeneralized shockAmount of lactic acid exceeds the livers ability to convert itMuscle and skin can function in aerobic conditions for short periodBrain most sensitive to hypo
13、xiaKrebs CycleAerobic conditions pyruvic acid enters mitochondriaProduces 6 CO2 molecules and 4 ATPElectron TransportOccurs in proteins bound to mitochondrial membraneAdditional 32 ATP produced Primary site of O2 utilization within cellProduce very little ATP on anarerobic conditionsCellular Metabol
14、ismTwo Step ProcessGlycolysisCell utilizing energy sourceReleases energyAerobic Metabolism: 95% of cellular EnergyRequires oxygen and glucoseKrebs cycle (citric acid cycle)Uses carbohydrates, proteins and fats to release energyOther ProcessesAnaerobic MetabolismInadequate oxygen pathwayByproducts: P
15、yruvic Acid Lactic AcidCellular death eventually occurs due to inadequate perfusionCirculatory SystemVascular SystemVascular System ArteriesArteries Tunica AdventitiaTunica Adventitia Tunica MediaTunica Media Tunica IntimaTunica Intima ArterioleArteriole Capillary: 7% of blood volumeCapillary: 7% of
16、 blood volume VenuleVenule VeinVein Constriction returns 20% (1 L) of blood to Constriction returns 20% (1 L) of blood to active circulationactive circulation13% of blood volume64% of blood volumeBlood VesselsSympathetic innervationVasoconstrictionAlpha 1 agonistList some drugs that have alpha 1 agonsist/ blocker effectsNamesIndicationsContraindicationsWhat physiological response would you expect?Why?Hydrostatic and Oncotic PressureTwo opposing forces that control net flow of fluid and nutrients
