外科急診創(chuàng)傷(英文)貫通傷課件

1、Sections Sections Introduction to Penetrating TraumaPhysics of Penetrating TraumaSpecific Tissue/Organ InjuriesSpecial Concerns with Penetrating Trauma38,000 Deaths in US annually due to shootings.Mechanisms of penetrating trauma Knives, Arrows, Nails, etcUnderstanding principles of energy exchange

2、increase the Index of Suspicion associated with the MOIIntroduction to Introduction to Penetrating TraumaPenetrating TraumaRecall Kinetic Energy Equation Greater the mass the greater the energy Double mass = double KE Greater the speed the greater the energy Double speed = 4x increase KEPhysics of P

3、hysics of Penetrating TraumaPenetrating Trauma2)()(2speedVelocityweightMassKE(continued)Physics of Physics of Penetrating TraumaPenetrating Trauma Small & Fast bullet can cause greater damage than large and slow. Different bullets of different weights traveling at different speeds cause Low Ener

4、gy/Low Velocity Knives and arrows Medium Energy/Medium Velocity Weapons Handguns, shotguns, low-powered rifles 250-400 mps High Energy/High Velocity Assault Rifles 600-1,000 mps(continued)Physics of Physics of Penetrating TraumaPenetrating Trauma Bullet spins as it travels down barrel Rifling in bar

5、rel Allows bullet to travel straight with slight yaw Bullet departs barrel, spinning with a slight wobble or yaw Weapon forced backward and absorbs energy Recoil(continued)Physics of Physics of Penetrating TraumaPenetrating Trauma Remainder of energy propels bullet forward at a high rate of speed. T

6、rajectory is curved due to gravity As bullet strikes object, it slows and energy is transferred to object. Law of Conservation of EnergyBallisticsBallistics Study of the characteristics of projectiles in motion and effects upon objects impacted Factors affecting energy exchange between a projectile

7、and body tissue Velocity Profile Stability Expansion & Fragmentation Secondary Impacts ShapeEnergy DissipationEnergy Dissipation Drag: wind resistance Cavitation: formation of a partial vacuum and cavity within a semi-fluid medium Profile: Size and shape of a projectile as it contacts a target L

8、arger the pro energy exchange Expansion and fragmentation results in damage Stability Allows for straighter trajectory Decreases after striking object results in tumblingAspects of BallisticsAspects of BallisticsVelocity Causes Trajectory Faster = straighter trajectory Slower = more curved due to gr

9、avityAspects of BallisticsAspects of BallisticsProfile Portion of bullet you see as it travels towards you Larger profile = greater energy exchange Caliber Diameter of a bullet (ID of gun) 0.22 caliber = 0.22 inches Bullets become unstable as they pass from one medium to another.Aspects of Ballistic

10、sAspects of BallisticsStability Bullet length increases bullet tumbling Can reduce the accuracy of the shot Reduced by Rifling in barrel (spinning) Yaw Gyroscopic effect on the center axis of the bullet that reduces tumbling Tumbling of bullet once it strikes object Reduces kinetic energy Greater ti

11、ssue damageBullet Gyroscopic EffectBullet Gyroscopic EffectAspects of BallisticsAspects of BallisticsExpansion & Fragmentation Results in increased profile Mushrooming Initial impact forces may result in fragmenting Greater tissue damageAspects of BallisticsAspects of BallisticsSecondary Impacts

12、 Bullet striking other objects can cause yaw and tumble Body Armor (Kevlar) Transmits energy throughout entire vest resulting in blunt trauma Myocardial Contusion Pulmonary Contusion Rib FracturesShape Handgun Ammunition = Blunt = Tumble Rifle Ammunition = Pointed = Piercing Handguns Small caliber,

13、short barrel, medium-velocity Effective at close range Severity of injury based upon organs damaged Rifle High-velocity, longer barrel, large caliber Increased accuracy at far distances Assault Rifles Large magazine, semi- or full-automatic Similar injury to hunting rifles Multiple woundsSpecific We

14、apon Specific Weapon CharacteristicsCharacteristicsShotgun Slug or pellets at medium velocity 00 (1/3”) to #9 (pin head sized) Larger the load, the smaller the number of projectiles Deadly at close rangeKnives & Arrows Low-energy & low-velocity Damage related to depth and angle of attack Mov

15、ement of the victim can increase damageSpecific Weapon Specific Weapon CharacteristicsCharacteristicsDamage PathwayDamage PathwayProjectile Injury Process Tip impacts tissue Tissue pushed forward and to the side Tissue collides with adjacent tissue Shock wave of pressure forward and lateral Moves pe

16、rpendicular to bullet path Rapid compression, crushes and tears tissue Cavity forms behind bullet pulling in debris with suction.Damage PathwayDamage Pathway Direct Injury Damage done as the projectile strikes tissue Pressure Shock Wave Human tissue is semi-fluid Solid and dense organs are damaged g

17、reatly Temporary Cavity Due to cavitation Permanent Cavity Due to seriously damaged tissue Zone of Injury Area that extends beyond the area of permanent injuryBallistics CavitationBallistics CavitationLow-Velocity WoundsLow-Velocity Wounds Objects Knives, Ice-picks, Arrows Flying objects or debris I

18、njury limited to tissue impacted Object pathway Object twisting or moved Oblique angle Attacker Characteristics Males: outward and crosswise Females: overhand and downward Density of tissue affects the efficiency of energy transmission Resiliency Strength and elasticity of an object Connective Tissu

19、e Absorbs energy and limits tissue damage Organs Solid Organs Dense and low resilience Hollow Organs Fluid filled: transmit energy = increased damage Air filled: absorbs energy = less damageSpecific Tissue & Specific Tissue & Organ InjuriesOrgan InjuriesLungs Air in lung absorbs energy Paren

20、chyma is compressed and rebounds Pneumothorax or hemothorax can resultBone Resists displacement until it shatters Alters projectile pathSpecific Tissue & Specific Tissue & Organ InjuriesOrgan InjuriesGeneral Body RegionsGeneral Body Regions Extremities Injury limited to resiliency of tissue

21、60-80% of injuries with 10% mortality Abdomen (Includes Pelvis) Highly susceptible to injury and hemorrhage Bowel perforation: 12-24 hrs peritoneal irritation Thorax Rib impact results in explosive energy Heart & great vessels have extensive damage due to lack of fluid compression Any large ches

22、t wound compromises breathingGeneral Body RegionsGeneral Body RegionsNeck Damages Trachea and Blood Vessels Neurological problems Sucking neck woundHead Cavitational energy trapped inside skull Serious bleeding and lethalWound CharacteristicsWound Characteristics Entrance Wounds Size of bullet pro n

23、on-deforming bullets Deforming projectiles may cause large wounds Close Range Powder Burns (Tattooing of powder) 1-2 mm circle of discoloration Localized subcutaneous emphysema Exit Wounds Appears to be “Blown” outward Pressure waveScene Size-Up Law-Enforcement DO NOT ENTER UNTIL SCENE IS SAFE! Weapons: Victim or Assailant Assailants IF A CRIME SCENE DOCUMENT DO NOT DISTURB EVIDENCE RETAIN CLOTHING, ETC LIMIT PERSONNEL INVOLVEMENTSpecial Concerns with Special Concerns with Penetrating TraumaPenetrating TraumaPenetrating Wound Assessment Internal Organ Injury Potenti