PHTLS Slides

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Kinematics of Trauma
Kimberly Ann Holmes Kenney RN, CNS-Rx, MS(N),
MS CCRN, CEN, CFRN, NREMT-P
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Objectives

• Discuss the laws of energy and motion.
• Discuss trauma associated with blunt impact and
  penetrating injury.
• Overview of the effects of energy distribution in
  MVCs.
• Review the kinematics of blast and violent
  injuries.
• Use kinematics to predict injury patterns.

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Kinetic Energy
KE
or
KE
Kinetic energy is the energy of motion.
4
Example of Kinetic Energy
The KE of a 150-lb. person traveling at 30 mph
would be
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Velocity vs. Mass

• 150 lb. person traveling at 30 mph 67,500 KE
  units
• 180 lb. person traveling at 30 mph 81,000 KE
  units
• 150 lb. person traveling at 40 mph 120,000 KE
  units

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Velocity
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Newtons First Law of Motion

• A body at rest will stay at rest.
• A body in motion will remainin motion.
• Unless what?

8
Newtons First Law and Blunt Trauma

• Car strikes pole.
• Driver continues moving forward.
• Anterior surface of body strikes steering wheel.
• Posterior body continues moving forward.
• Organs compressed within body.

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Law of Conservation of Energy

• Energy cannot be created.
• Energy cannot be destroyed.

0
But, energy can change forms and can be
transferred.
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How does the Law of Conservation of Energy
pertain to trauma?
Can you give some examples?
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Deceleration and Acceleration
Compression Injury
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Deceleration and Acceleration
Shear Injury
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Organ Injury
In a 50 mph MVC, what types injuries would occur
if the patient were to strike the windshield?
14
Head Injury

• Fractures.
• Ligamentous injuries.
• Soft tissue injury.
• Brain injury.
• Cord damage.

15
Torso Injury

• Rib fractures.
• Heart lung damage.
• Abdominal organ damage.
• Major vessel damage.

16
Extremity Injury

• Fractures.
• Ligamentous injury.
• Soft tissue injury.

17
Types of Motor Vehicle Collisions

• Frontal impact.
• Lateral impact.
• Rotational impact.
• Rear impact.
• Rollover.

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What type of injury patterns might you see in a
frontal impact?
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Frontal Impact - Occupant Pathways
What injuries would you expect with an up and
over pathway?
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Injuries with Up Over Pathway
continued...

• Head injuries.
• Spine injuries.
• Chest injuries.
• Fractures.
• Pneumothorax.
• Hemothorax.
• Contusions.
• Great vessel injury.

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Injuries with Up Over Pathway
continued...

• Abdominal injuries.
• Solid organs.
• Hollow organs.
• Diaphragm.
• Fractured pelvis.

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Frontal Impact - Occupant Pathways
What injuries would you expect with a down and
under pathway?
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Injuries with Down Under Pathway

• Posterior knee/hip dislocations.
• Femur fractures.
• Lower extremity fractures.
• Pelvic/acetabular fractures.

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Rear Impact
What types of injuries would you expect?
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Lateral Impact
What types of injuries would you expect?
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Body Motion during Lateral Impacts

• Neck
• Chest
• Pelvis

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Rotational Impact
What types of injuries would you expect?
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Rollover
What injury patterns might you see following this
collision?
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Lap Restraint Device

• Properly positioned lap restraint.
• Improperly positioned lap restraint.

What types of injuries should you anticipate?
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Lap Shoulder Restraint System

• Shoulder harness only lap belt not used.
  (Victim moves down and under).
• Lap restraint only shoulder harness not used.
  (Victim moves up and over)

What types of injuries should you anticipate?
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Airbag Deployment

• What types of injuries would you expect to see?
• What injuries would occur in a second collision?

32
Airbag Deployment

• What concerns would you have about a
• Small patient?
• Child in a car seat?

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Motorcycle Collisions
Mandatory helmet laws have been associated with
up to 300 fewer head injuries and deaths.
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Types of Impact Frontal/Ejection
How many impacts did this collision involve?
What types of injuries would you expect to see?
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Types of Impact Lateral
How many impacts did this collision involve?
What types of injuries would you expect to see?
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Pedestrian vs. Motor Vehicle
How would the injury patterns differ between the
adult and the child?
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Falls

• Impact surface.
• (Harder surface greater injury.)
• Height.
• (Greater height greater injury.)
• Falls from a distance of more than three times
  the patients height produce critical injuries.

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Falls

• Deceleration injuries.
• Liver.
• Aorta.
• Spleen.
• Kidney.

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Landing Feet First(Don Juan Syndrome)

• Injuries seen in patients landing feet first
• Bilateral heel fractures.
• Ankle fractures.
• Distal tibia/fibula fractures.
• Knee dislocations.
• Femur fractures.
• Hip injuries.
• Spine compression fractures.

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Landing Arms/Hands First

• Physical findings
• Colles fractures of wrists.
• Shoulder dislocations.
• Fractures of the clavicles.

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Landing Head-First

• Physical findings
• C-spine injuries.
• Facial injuries.
• CNS damage.

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Sports Recreational Activity Mechanisms

• Acceleration
• Deceleration
• Hyperextension
• Hyperflexion
• Twisting
• Falling

43
Predicting Sports-Related Injuries

• Kinematics forces involved.
• Equipment contributing to injury.
• Involvement of protective equipment.
• Nature of the sport.

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Blast Injuries

• Warfare.
• Civilian areas.
• Mines.
• Shipyards.
• Chemical plants.
• Tank trucks.
• Refineries.
• Fireworks firms.
• Silos.
• LP gas tanks.

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Blast-Related Injuries

• Three mechanisms of injury
• Primary.
• Secondary.
• Tertiary.

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Primary Phase Injuries

• Cause pressure wave from blast.
• Affected area gas-containing organs.
• Injuries
• Pulmonary bleeding.
• Pneumothorax.
• Air emboli.
• Perforation of the GI tract.
• Burns.
• Death may occur in absence of outward signs.

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Secondary Phase Injuries

• Cause flying debris.
• Affected area
• Body surface.
• Skeletal system.
• Injuries
• Lacerations.
• Fractures.
• Burns.

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Tertiary Phase Injuries

• Cause victim thrown against an object.
• Affected area area of impact or referred
  energy.
• Injuries similar to those sustained in a
  vehicle ejection.

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Penetrating Trauma

• Physics.
• Weapon velocity.
• Bullet design.

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Penetrating Trauma

• Newtons First Law and ballistics
• Bullet in brass cartridge is at rest.
• Bullet propelled by rapid combustion of powder.
• Bullet leaves barrel of gun.
• Bullet strikes a body.
• Bullet transfers energy to victim.

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Low-Energy Injuries

• Low velocity.
• Usually hand-driven weapons.
• Less secondary trauma.
• Multiple wounds from a single weapon.

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Low-Energy Penetrating Wounds
How does the length of the weapon relate to the
cone of damage?
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Assessment of Low-Energy Injuries

• Type of weapon involved.
• Path of weapon.
• Depth of penetration.
• Number of wounds.
• Underlying anatomy.

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Medium-Energy Penetrating Injuries
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High-Energy Penetrating Injuries
How do these weapons differ from handguns and
shotguns?
How do the wounds differ internally and
externally?
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Projectile - Frontal Area

• The larger the frontal area of the projectile,
  the greater the damage.
• The larger the cavitation and the greater the
  damage, the greater the exit wound.

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Gunshot Wounds - Cavitation
Reformation by elastic tissue
Temporary cavity
Direction of travel
Bullet
Permanent cavity
Compression and crush
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Gunshot Wounds
Describe the difference between entrance and
exit wounds.
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Tumbling Projectiles

• Some projectiles are designed to tumble.
• Tumbling creates greater tissue damage and more
  tissue destruction.

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Fragmentation
The shotgun round is the ultimate in
fragmentation.
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Considerations for Penetrating Trauma

• Scene safety.
• Patient care is the priority!
• Weapon type.
• Range at which weapon was fired.
• Number of entrance and exit wounds.
• Underlying anatomy and track.
• Crime scene preservation.

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Kinematics Summary
The cornerstone of assessment is early
consideration of kinematics to predict hidden
injury.