外科急診創(chuàng)傷(英文)-貫通傷40張課件

1、Penetrating TraumaPenetrating TraumaSections Introduction to Penetrating TraumaPhysics of Penetrating TraumaSpecific Tissue/Organ InjuriesSpecial Concerns with Penetrating TraumaSections Introduction to Pene38,000 Deaths in US annually due to shootings.Mechanisms of penetrating traumaKnives, Arrows,

2、 Nails, etcUnderstanding principles of energy exchange increase the Index of Suspicion associated with the MOIIntroduction to Penetrating Trauma38,000 Deaths in US annually dRecall Kinetic Energy EquationGreater the mass the greater the energyDouble mass = double KEGreater the speed the greater the

3、energyDouble speed = 4x increase KEPhysics of Penetrating Trauma(continued)Recall Kinetic Energy Equation外科急診創(chuàng)傷(英文)-貫通傷40張課件Physics of Penetrating TraumaSmall & Fast bullet can cause greater damage than large and slow.Different bullets of different weights traveling at different speeds causeLow Ener

4、gy/Low VelocityKnives and arrowsMedium Energy/Medium Velocity WeaponsHandguns, shotguns, low-powered rifles250-400 mpsHigh Energy/High VelocityAssault Rifles600-1,000 mps(continued)Physics of Penetrating TraumaPhysics of Penetrating TraumaBullet spins as it travels down barrelRifling in barrelAllows

5、 bullet to travel straight with slight yawBullet departs barrel, spinning with a slight wobble or yawWeapon forced backward and absorbs energyRecoil(continued)Physics of Penetrating TraumaPhysics of Penetrating TraumaRemainder of energy propels bullet forward at a high rate of speed.Trajectory is cu

6、rved due to gravityAs bullet strikes object, it slows and energy is transferred to object.Law of Conservation of EnergyPhysics of Penetrating TraumaBallisticsStudy of the characteristics of projectiles in motion and effects upon objects impactedFactors affecting energy exchange between a projectile

7、and body tissueVelocityProfileStabilityExpansion & FragmentationSecondary ImpactsShapeBallisticsStudy of the charactEnergy DissipationDrag: wind resistanceCavitation: formation of a partial vacuum and cavity within a semi-fluid mediumProfile: Size and shape of a projectile as it contacts a targetLar

8、ger the profile=greater energy exchangeExpansion and fragmentation results in damageStabilityAllows for straighter trajectoryDecreases after striking object results in tumblingEnergy DissipationDrag: 外科急診創(chuàng)傷(英文)-貫通傷40張課件外科急診創(chuàng)傷(英文)-貫通傷40張課件外科急診創(chuàng)傷(英文)-貫通傷40張課件Aspects of BallisticsVelocityCauses Traject

9、oryFaster = straighter trajectorySlower = more curved due to gravityAspects of BallisticsVelocityAspects of BallisticsProfilePortion of bullet you see as it travels towards youLarger profile = greater energy exchangeCaliberDiameter of a bullet (ID of gun)0.22 caliber = 0.22 inchesBullets become unst

10、able as they pass from one medium to another.Aspects of BallisticsProfileAspects of BallisticsStabilityBullet length increases bullet tumblingCan reduce the accuracy of the shotReduced by Rifling in barrel (spinning)YawGyroscopic effect on the center axis of the bullet that reduces tumblingTumbling

11、of bullet once it strikes objectReduces kinetic energyGreater tissue damageAspects of BallisticsStabilityBullet Gyroscopic EffectBullet Gyroscopic EffectAspects of BallisticsExpansion & FragmentationResults in increased profileMushroomingInitial impact forces may result in fragmentingGreater tissue

12、damageAspects of BallisticsExpansion外科急診創(chuàng)傷(英文)-貫通傷40張課件Aspects of BallisticsSecondary ImpactsBullet striking other objects can cause yaw and tumbleBody Armor (Kevlar)Transmits energy throughout entire vest resulting in blunt traumaMyocardial ContusionPulmonary ContusionRib FracturesShapeHandgun Ammu

13、nition = Blunt = TumbleRifle Ammunition = Pointed = PiercingAspects of BallisticsSecondaryHandgunsSmall caliber, short barrel, medium-velocityEffective at close rangeSeverity of injury based upon organs damagedRifleHigh-velocity, longer barrel, large caliberIncreased accuracy at far distancesAssault

14、 RiflesLarge magazine, semi- or full-automaticSimilar injury to hunting riflesMultiple woundsSpecific Weapon CharacteristicsHandgunsSpecific Weapon CharacShotgunSlug or pellets at medium velocity00 (1/3”) to #9 (pin head sized)Larger the load, the smaller the number of projectilesDeadly at close ran

15、geKnives & ArrowsLow-energy & low-velocityDamage related to depth and angle of attackMovement of the victim can increase damageSpecific Weapon CharacteristicsShotgunSpecific Weapon CharactDamage PathwayProjectile Injury ProcessTip impacts tissueTissue pushed forward and to the sideTissue collides wi

16、th adjacent tissueShock wave of pressure forward and lateralMoves perpendicular to bullet pathRapid compression, crushes and tears tissueCavity forms behind bullet pulling in debris with suction.Damage PathwayProjectile Injur外科急診創(chuàng)傷(英文)-貫通傷40張課件Damage PathwayDirect InjuryDamage done as the projectile

17、 strikes tissuePressure Shock WaveHuman tissue is semi-fluidSolid and dense organs are damaged greatlyTemporary CavityDue to cavitationPermanent CavityDue to seriously damaged tissueZone of InjuryArea that extends beyond the area of permanent injuryDamage PathwayDirect InjuryBallistics CavitationBal

18、listics CavitationLow-Velocity WoundsObjectsKnives, Ice-picks, ArrowsFlying objects or debrisInjury limited to tissue impactedObject pathwayObject twisting or movedOblique angleAttacker CharacteristicsMales: outward and crosswiseFemales: overhand and downwardLow-Velocity WoundsObjectsDensity of tiss

19、ue affects the efficiency of energy transmissionResiliencyStrength and elasticity of an objectConnective TissueAbsorbs energy and limits tissue damageOrgansSolid OrgansDense and low resilienceHollow OrgansFluid filled: transmit energy = increased damageAir filled: absorbs energy = less damageSpecifi

20、c Tissue & Organ InjuriesDensity of tissue affects the LungsAir in lung absorbs energyParenchyma is compressed and reboundsPneumothorax or hemothorax can resultBoneResists displacement until it shattersAlters projectile pathSpecific Tissue & Organ InjuriesLungsSpecific Tissue & Organ General Body Re

21、gionsExtremitiesInjury limited to resiliency of tissue60-80% of injuries with 10% mortalityAbdomen (Includes Pelvis)Highly susceptible to injury and hemorrhageBowel perforation: 12-24 hrs peritoneal irritationThoraxRib impact results in explosive energyHeart & great vessels have extensive damage due

22、 to lack of fluid compressionAny large chest wound compromises breathingGeneral Body RegionsExtremitieGeneral Body RegionsNeckDamages Trachea and Blood VesselsNeurological problemsSucking neck woundHeadCavitational energy trapped inside skullSerious bleeding and lethalGeneral Body RegionsNeckWound C

23、haracteristicsEntrance WoundsSize of bullet profile for non-deforming bulletsDeforming projectiles may cause large woundsClose RangePowder Burns (Tattooing of powder)1-2 mm circle of discolorationLocalized subcutaneous emphysemaExit WoundsAppears to be “Blown” outwardPressure waveWound Characteristi

24、csEntrance 外科急診創(chuàng)傷(英文)-貫通傷40張課件Scene Size-UpLaw-EnforcementDO NOT ENTER UNTIL SCENE IS SAFE!Weapons: Victim or AssailantAssailantsIF A CRIME SCENEDOCUMENTDO NOT DISTURB EVIDENCERETAIN CLOTHING, ETCLIMIT PERSONNEL INVOLVEMENTSpecial Concerns with Penetrating TraumaScene Size-UpSpecial Concerns Penetrating Wound AssessmentInternal Organ Injur