Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Division 3 Trauma Emergencies

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Chapter 18 Penetrating Trauma

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Topics Introduction to Penetrating Trauma Physics of Penetrating Trauma Specific Tissue/Organ Injuries Special Concerns with Penetrating Trauma

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Introduction to Penetrating Trauma 28,000 deaths in U.S. annually due to shootings. Mechanisms of penetrating trauma: –Knives, arrows, nails, etc. Understanding principles of energy exchange increases the index of suspicion associated with the MOI.

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Definitions Yaw Trajectory Velocity Profile Stability Expansion Fragmentation Secondary impacts Shape Drag Cavitation

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Physics of Penetrating Trauma (1 of 5) Kinetic Energy KE = mass (weight) x velocity (speed) 2 2 Greater the mass the greater the energy –Double mass = double KE Greater the speed the greater the energy –Double speed = 4x increase KE

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Small and fast bullets can cause greater damage than large and slow bullets. Physics of Penetrating Trauma (2 of 5)

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Physics of Penetrating Trauma (3 of 5) Different bullets of different weights traveling at different speeds cause: –Low Energy/Low Velocity Knives and arrows –Medium Energy/Medium Velocity Weapons Handguns, shotguns, low-powered rifles mps –High Energy/High Velocity Assault rifles 600-1,000 mps

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Physics of Penetrating Trauma (4 of 5) Bullet spins as it travels down barrel. –Rifling in barrel –Allows bullet to travel straight with slight yaw Bullet departs barrel, spinning with a slight wobble or yaw. Weapon is forced backward and absorbs energy. –Recoil

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Physics of Penetrating Trauma (5 of 5) Remainder of energy propels bullet forward at a high rate of speed. Trajectory is curved due to gravity. As bullet strikes object, it slows and energy is transferred to object. –Law of Conservation of Energy

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Bullet Gyroscopic Effect

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Ballistics Study of the characteristics of projectiles in motion and effects upon objects impacted Factors affecting energy exchange between a projectile and body tissue –Velocity –Profile –Stability –Expansion and fragmentation –Secondary Impacts –Shape

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Aspects of Ballistics (1 of 5) Velocity –Causes trajectory Faster = straighter trajectory Slower = more curved due to gravity

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Energy 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 –Larger the profile = greater energy exchange –Expansion and fragmentation result in damage Stability –Allows for straighter trajectory –Decreases after striking object; results in tumbling

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Aspects of Ballistics (2 of 5) Profile –Portion of bullet you see as it travels toward 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. Robert S. Porter

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Aspects of Ballistics (3 of 5) Stability –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 Increases rate of energy exchange Greater tissue damage

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Aspects of Ballistics (4 of 5) Expansion and Fragmentation –Result in increased profile. –Mushrooming. –Initial impact forces may result in fragmenting. –Greater tissue damage.

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Secondary Impacts –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 fractures Shape –Handgun ammunition = Blunt = Tumble –Rifle ammunition = Pointed = Piercing Aspects of Ballistics (5 of 5)

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Projectile Types Simple lead Semi-jacketed –Hollow point Full jacket

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Lead Projectiles Oldest and simplest to manufacture Relatively soft and deformable Readily foul the barrel at higher muzzle velocity

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Semi-Jacketed Also referred to as hollow point –“Dum-dum” Designed to promote expansion

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Full Metal Casing (FMC) Prescribed by Geneva Convention Theoretically creates less tissue damage because it resists fragmentation

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Deformation Creates increased cross section. Promotes transfer of kinetic energy. Geometry dictates that… –2-fold increase in diameter results in a four-fold increase in area. This process is (in theory) promoted by partial jacket design. Robert S. Porter

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Fragmentation (1 of 2) Increases surface area Increases efficiency of kinetic energy transfer Multiple projectiles Robert S. Porter

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Fragmentation (2 of 2) Significant wounding potential Requires high velocity to reliably occur Particularly destructive when combined with concomitant cavitation wave

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ The Tumble Effect Projectiles travel through a dense media with their center of gravity forward. Tumble is an inevitable result of rifle projectile design.

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Cavitation Definition –The radial dispersion of energy created by a moving object Well tolerated by muscle and lung Poorly tolerated by high water content tissue –CNS –Liver

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Cavitation and Fragmentation Particularly destructive when the two effects are combined Tissue stretched by cavitation/cut by fragmentation

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Stippling Deposition of gunpowder in a “tattooing” pattern around the entrance wound Usually indicative of close range –Roughly 3 to 8 inches

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Fouling The concentric deposition of gunpowder at the entrance site Indicative of contact or immediate proximity of the weapon

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Specific Weapon Characteristics (1 of 4) Handguns –Most commonly used weapons in homicides –Small caliber, short barrel, medium velocity –Effective at close range –Severity of injury based upon organs damaged –Increasing popularity of semi-automatic weapons

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Specific Weapon Characteristics (2 of 4) Rifles –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 wounds

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Specific Weapon Characteristics (3 of 4) Shotguns –Slug or pellets at medium velocity 00 (1/3”) to #9 (pin head size) Larger the load, the smaller the number of projectiles Deadly at close range

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Specific Weapon Characteristics (4 of 4) Knives and Arrows –Low energy and low velocity –Damage related to depth and angle of attack –Movement of the victim can increase damage

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Shotgun – Barrel Choke ChokeConstriction(1/1000) Cylinder boreNone Improved5 to 10 Modified20 Improved Modified30 Full choke40

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Shotgun – Shell Construction Standard weight of shot Wadding separates powder from shot Shot usually contained by plastic collar

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Shotgun – Estimating Range Wadding in the wound implies very close range.

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Low-Velocity Wounds Objects –Knives, ice picks, arrows –Flying objects or debris Injury limited to tissue impacted –Object pathway –Object twisting or moved –Oblique angle Attacker Characteristics –Males: outward and crosswise –Females: overhand and downward

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Damage Pathway Direct Injury –Damage done as the projectile strikes tissue Pressure Shock Wave –Human tissue semi- fluid –Solid and dense organs damaged greatly Temporary Cavity –Due to cavitation Permanent Cavity –Due to seriously damaged tissue Zone of Injury –Area that extends beyond the area of permanent injury

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Specific Tissue and Organ Injuries (1 of 2) Connective Tissue –Absorbs energy and limits tissue damage Organs –Solid organs Dense and low resilience –Hollow organs Fluid filled: transmit energy = increased damage Air filled: absorb energy = less damage

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Lungs –Air in lung absorbs energy. –Parenchyma is compressed and rebounds. –Pneumothorax or hemothorax can result. Bone –Resists displacement until it shatters. –Alters projectile path. Specific Tissue and Organ Injuries (2 of 2)

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ General Body Regions (1 of 2) Extremities –Injury limited to resiliency of tissue –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 and great vessels have extensive damage due to lack of fluid compression. –Any large chest wound compromises breathing.

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ General Body Regions (2 of 2) Neck –Damages trachea and blood vessels –Neurological problems –Sucking neck wound Head –Cavitational energy trapped inside skull –Serious bleeding, lethal

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Wound Characteristics Entrance Wounds –Size of bullet profile for non-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 –Appear to be “blown” outward Pressure wave

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Special Concerns (1 of 4) Scene 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 involvement.

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Penetrating Wound Assessment –Internal organ injury potential –Entrance and exit wounds PROVIDE RAPID TRANSPORT FOR ANY GSW TO HEAD, CHEST, OR ABDOMEN. TREAT AGGRESSIVELY FOR SHOCK!! Special Concerns (2 of 4)

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Penetrating Wound Care –Facial wounds Chest Wounds –Pneumothorax –Pericardial tamponade Special Concerns (3 of 4)

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Impaled Objects –Low energy –Dangerous to remove –DO NOT REMOVE UNLESS In cheek Interferes with CPR Special Concerns (4 of 4)

Bledsoe et al., Essentials of Paramedic Care: Division 1II © 2006 by Pearson Education, Inc. Upper Saddle River, NJ Summary Introduction to Penetrating Trauma Physics of Penetrating Trauma Specific Tissue/Organ Injuries Special Concerns with Penetrating Trauma