Transcript Penetrating Trauma - Central Piedmont Community College

Penetrating Trauma
Penetrating Trauma
• 38,000 deaths in US annually due to shootings
• Mechanisms of penetrating trauma
– Knives, Arrows, Nails, etc
• Understanding principles of energy exchange
increase the Index of Suspicion associated with
the MOI
Penetrating Trauma
• Kinetic Energy Equation
Mass( weight)  Velocity( speed) 2
KE 
2
– Greater the mass, the greater the energy
• Double mass = double KE
– Greater the speed, the greater the energy
• Double speed = 4x increase KE
Penetrating Trauma
• A small & fast bullet can cause greater damage
than a large and slow one.
– Different bullets of different weights traveling
at different speeds cause:
• Low Energy/Low Velocity
–Knives, handguns and arrows
–Injury caused by direct contact and
cavitation
Penetrating Trauma
• Medium Energy/Medium Velocity Weapons
–Handguns, shotguns, low-powered rifles
–250-400 mps
• High Energy/High Velocity
–Assault Rifles
–600-1,000 mps
–Military, hunting rifles & high powered
hand guns
–Extensive injury due to high pressure
cavitation
Penetrating Trauma
• 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 forced backward and absorbs energy
– Recoil
Penetrating Trauma
• 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
Penetrating Trauma
• Factors affecting energy exchange between a
projectile and body tissue:
– Velocity
– Profile
– Stability
– Expansion & Fragmentation
– Secondary Impacts
– Shape
Penetrating Trauma
• Drag:
– wind resistance
• Cavitation:
– formation of a partial vacuum and cavity
within a semi-fluid medium
Penetrating Trauma
• Profile:
– Size and shape of a projectile as it contacts a
target
– Larger the profile=greater energy exchange
– Expansion and fragmentation results in
damage
– Factors that affect energy exchange between
projectile is equal to Velocity and Stability
Penetrating Trauma
• Stability
– Allows for straighter trajectory
– Decreases after striking object results in
tumbling
Penetrating Trauma
• Velocity
– Causes Trajectory
• Faster = straighter trajectory
• Slower = more curved due to gravity
Penetrating Trauma
• Profile
– 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.
Penetrating Trauma
• 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
Penetrating Trauma
– Tumbling of bullet once it strikes object
• Reduces kinetic energy
• Greater tissue damage
Penetrating Trauma
• Expansion & Fragmentation
– Results in increased profile
– Mushrooming
– Initial impact forces may result in fragmenting
– Greater tissue damage
Penetrating Trauma
• 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
Penetrating Trauma
• Shape
– Handgun Ammunition = Blunt = Tumble
– Rifle Ammunition = Pointed = Piercing
Bullet striking Kevlar type vest
Penetrating Trauma
• Handguns
– Small caliber, 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
Penetrating Trauma
• Assault Rifles
– Large magazine, semi- or full-automatic
– Similar injury to hunting rifles
– Multiple wounds
Penetrating Trauma
• Shotgun
– Slug or pellets at medium velocity
• 00 (1/3”) to #9 (pin head sized)
• Larger the load, the smaller the number of
projectiles
• More Deadly at close range
Penetrating Trauma
• Knives & Arrows
– Low-energy & low-velocity
– Damage related to depth and angle of attack
– Movement of the victim can increase damage
Penetrating Trauma
• Projectile 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 perpendicular to bullet path
Penetrating Trauma
– Rapid compression, crushes and tears tissue
– Cavity forms behind bullet pulling in debris
with suction.
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• Direct Injury
– Damage done as the projectile strikes tissue
• Pressure Shock Wave
– Human tissue is semi-fluid
– Solid and dense organs are damaged greatly
Penetrating Trauma
• Organs
– Solid Organs
• Dense and low resilience
– Hollow Organs
• Fluid filled: transmit energy = increased
damage
• Air filled: absorbs energy = less damage
Penetrating Trauma
• Temporary Cavity
– Due to cavitation
• Permanent Cavity
– Due to seriously damaged tissue
• Zone of Injury
– Area that extends beyond the area of
permanent injury
Penetrating Trauma
Temporary Cavity
Permanent Cavity
Penetrating Trauma
• Much of the damage done by a bullet results
from the tumbling motion and the cavitation in
the tissue. This is the bullet track in clay of a .38
caliber round, demonstrating that the wound
track is much larger than .38 inches (closer to 3
inches).
Penetrating Trauma
• 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
Penetrating Trauma
• Knives, needles, and ice picks
• Cause tissue damage by their sharp, cutting
edges
– Amount of tissue crushed is usually minimal
because the amount of force applied in the
wounding process is small
• Tissue damage is usually limited to the pathway
of the projectile
Penetrating Trauma
• Effects on Parts of the body
Penetrating Trauma
• Neck
– Damages trachea and blood vessels
– Neurological problems
– Sucking neck wound
• Head
– Cavitational energy trapped inside skull
– Serious bleeding and lethal
Penetrating Trauma
• Gunshot wounds to the head are typically
devastating
– Patients frequently sustain severe face and
neck injuries
• Significant blood loss
• Difficulty in maintaining airway control
• Spinal instability
Penetrating Trauma
• Thorax
– Rib impact results in explosive energy
– Heart & great vessels have extensive damage
due to lack of fluid compression
– Any large chest wound compromises
breathing
Penetrating Trauma
Injuries Associated
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Tracheobronchial tree lacerations
Esophageal lacerations
Penetrating cardiac injuries
Pericardial tamponade
Spinal cord injuries
Diaphragm trauma
Intra-abdominal penetration with associated
organ injury
Penetrating Trauma
• Closed pneumothorax
• Open pneumothorax (including sucking chest
wound)
• Tension pneumothorax
• Pneumomediastinum
• Hemothorax
• Hemopneumothorax
• Laceration of vascular structures
Penetrating Trauma
• Lungs
– Air in lung absorbs energy
– Pneumothorax or hemothorax can result in an
accumulation of up to 3000 ml of blood in
each side of the chest.
Penetrating Trauma
• Open Pneumothorax
– Free passage of air between atmosphere and
pleural space
– Air replaces lung tissue
– Mediastinum shifts to uninjured side
Penetrating Trauma
• Simple Pneumothorax
– AKA: Closed Pneumothorax
• Progresses into Tension Pneumothorax
– Occurs when lung tissue is disrupted and air
leaks into the pleural space
Penetrating Trauma
– Progressive Pathology
• Air accumulates in pleural space
• Lung collapses
• Alveoli collapse (atelectasis)
• Reduced oxygen and carbon dioxide
exchange
Penetrating Trauma
• Ventilation/Perfusion
–Increased ventilation but no alveolar
perfusion
–Reduced respiratory efficiency results in
HYPOXIA
Penetrating Trauma
– Air will be drawn through wound if wound is
2/3 diameter of the trachea or larger
– Signs & Symptoms
• Penetrating chest trauma
• Sucking chest wound
• Frothy blood at wound site
• Severe dyspnea
• Hypovolemia
Penetrating Trauma
• Tension Pneumothorax
– Buildup of air under pressure in the thorax
– Excessive pressure reduces effectiveness of
respiration
– Air is unable to escape from inside the pleural
space
– Progression of Simple or Open Pneumothorax
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• Dyspnea
– Tachypnea at first
• Progressive ventilation/perfusion mismatch
– Atelectasis on uninjured side
• Hypoxemia
• Hyperinflation of injured side of chest
• Hyper-resonance of injured side of chest
Penetrating Trauma
• Diminished then absent breath sounds on
injured side
• Cyanosis
• Diaphoresis
• JVD
• Hypotension
• Hypovolemia
• Tracheal Shifting = LATE SIGN
Penetrating Trauma
• Hemothorax
– Accumulation of blood in the pleural space
– Serious hemorrhage may accumulate 1,500
ml of blood
• Mortality rate of 75%
• Each side of thorax may hold up to 3,000
ml
Penetrating Trauma
– Blood loss in thorax causes a decrease in
tidal volume
• Ventilation/Perfusion
– Typically accompanies pneumothorax
• Hemopneumothorax
Penetrating Trauma
• Blunt or penetrating chest trauma
• Shock
– Dyspnea
– Tachycardia
– Tachypnea
– Diaphoresis
– Hypotension
• Dull to percussion over injured side
Penetrating Trauma
• Pericardial Tamponade
– Restriction to cardiac filling caused by blood
or other fluid within the pericardium
– Occurs in <2% of all serious chest trauma
• However, very high mortality rate
Penetrating Trauma
– Results from tear in the coronary artery or
penetration of myocardium
• Blood seeps into pericardium and is unable
to escape
• 200-300 ml of blood can restrict
effectiveness of cardiac contractions
–Removing as little as 20 ml can provide
relief
Penetrating Trauma
• Dyspnea
• Possible cyanosis
• Beck’s Triad
– JVD
– Distant heart tones
– Hypotension or narrowing pulse pressure
• Weak, thready pulse
• Shock
Penetrating Trauma
• Kussmaul’s sign
– Decrease or absence of JVD during
inspiration
• Pulsus Paradoxus
– Drop in SBP >10 during inspiration
– Due to increase in CO2 during inspiration
• PEA
Penetrating Trauma
• Abdominal Injuries
Penetrating Trauma
• A gunshot wound to the abdomen usually
requires surgery to determine the extent of injury
• May affect multiple organ systems
– Damage to air-filled and solid organs
– Vascular injury
– Spinal column and spinal cord injury
Penetrating Trauma
• 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
Penetrating Trauma
• Gunshot wounds to the extremities:
– Are occasionally life-threatening
– May result in lifelong disability
Penetrating Trauma
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• 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
Penetrating Trauma
• Exit Wounds
– Appears to be “blown” outward
• Pressure wave
Penetrating Trauma
• Scene Size-Up
– Law enforcement
• DO NOT ENTER UNTIL SCENE IS SAFE!
– Weapons: Victim or Assailant
– Assailants
Penetrating Trauma
– IF A CRIME SCENE
• DOCUMENT
• DO NOT DISTURB EVIDENCE
• RETAIN CLOTHING, ETC
• LIMIT PERSONNEL INVOLVEMENT
Penetrating Trauma
• Impaled Objects
– Low-energy
– Dangerous to remove
– DO NOT REMOVE
• UNLESS
–In cheek
–Interferes with CPR: ASSESS!!!
Penetrating Trauma
• When evaluating a patient with a stab wound:
– Attempt to identify the type of wounding object
– Consider the possibility of:
• Multiple wounds
• Embedded penetrating objects
• Extensive internal damage to organs of the
thorax and abdomen
• Penetration of multiple body cavities
– A high degree of suspicion is also indicated
for stab wounds to areas of the back and flank
Penetrating Trauma
You are dispatched to the scene of a patient with a
possible impelled object.
• This could be:
– 1. Gunshot wound
– 2. Stabbing
– 3. Foreign object from an accident
• a. pipe
• b. stick
• c. glass
Penetrating Trauma
What you should do:
1. Is the scene safe?
2. Don proper PPE
3. Get the number of patients
a. Call for additional help if needed
4. Evaluate patient’s ABCs
a. Advise Medic of your situation and patient report if
possible
Penetrating Trauma
5. Treat life-threatening injuries
6. Apply direct pressure to wound area.
a. Look for entrance and exit
7. Assess vitals
8. Place patient on high concentration
a. Oxygen with n/rb mask 12+lpm
b. Asst bvm if needed
Penetrating Trauma
9. Apply dressing
a. Allow Medic to view wound (per protocol) prior to
bandaging
b. If entrance is in lung area, assess for pneumothorax
1. Place occlusive dressing over site and secure on
three sides.
c. If entrance is in area around neck
a. Place occlusive dressing over site and secure on
all sides
Penetrating Trauma
10. Stabilize impaled object
11. Maintain spinal immobilization
12. Reassure patient that all possible is being
done
13. Assist in packaging
14. Reassess vitals every 5 minutes
15. Continue to monitor and treat patient
16. Assist Medic as needed
Follow all local medical protocols and department
SOG’s
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