Chapter 25 Trauma Overview Notes

Mechanism of Injury (MOI)

• Define terms: mechanism of injury, blunt trauma.
• Explain the relationship of MOI to potential energy.
• Discuss effects of high, medium, and low velocity penetrating trauma.
• Discuss primary, secondary, tertiary, and miscellaneous blast injuries.

Trauma Overview

• For individuals younger than 44, traumatic injuries are the leading cause of death in the United States.
• Trauma results from physical forces sustained on the body.
• Medical emergencies are illnesses or conditions not caused by an outside force.
• Index of suspicion: awareness and concern for potentially serious underlying injuries.
• Traumatic injury occurs when body tissues are exposed to energy levels beyond their tolerance.

Physics of Trauma

• Mechanism of injury describes the injury transmission acting on the body.
• Three concepts of energy related to injury:
  • Potential energy.
  • Kinetic energy.
  • Energy of work.
• Law of conservation of energy: energy can neither be created nor destroyed, only converted or transformed.
• Work is defined as force acting over a specific distance.
• Forces that bend, pull, and compress tissues beyond limits cause injury.
• Kinetic energy: energy of a moving object.
  • Formula: \frac{1}{2} \times \text{mass} \times \text{velocity}^2 = \text{kinetic energy}
• Potential energy: product of mass, force of gravity, and height.
  • Related to falling objects.

Mechanisms of Injury (MOI)

• Different MOIs produce different types of injury.
• Non-significant MOIs:
  • Isolated injury to one body part.
  • Fall from a low-level height without loss of consciousness.
• Significant MOIs:
  • Injury to more than one body system (multi-system trauma).
  • Falls from significant heights.
  • Motor vehicle and motorcycle crashes.
  • Vehicles versus pedestrians.
  • Gunshot wounds and stabbings.

Types of Trauma

• Traumatic injuries are divided into: blunt trauma and penetrating trauma.
• Blunt Trauma:
  • Results from force to the body without penetrating soft tissues, internal organs, or cavities.
• Penetrating Trauma:
  • Injury caused by objects that pierce and penetrate the body surface and tissues.
• An MOI can cause both blunt and penetrating trauma.

Blunt Trauma

• Results from objects making contact but not penetrating the body.
• Most common MOIs: motor vehicle crashes and falls.
• Skin discoloration and pain are signs of blunt trauma.

Vehicle Crashes

• Consist of three collisions:
  • First collision: vehicle impacts another object.
    • Damage indicates severity of the mechanism.
    • Speed of the vehicle affects damage and injuries.
  • Second collision: passenger impacts the interior of the vehicle.
    • Common injuries: lower extremity fractures, rib fractures, and head trauma.
  • Third collision: internal organs impact the body walls.
    • Coup-countercoup injuries: brain hits the inside of the skull (coup) and rebounds to hit the opposite side (countercoup).
• Internal injuries can be life-threatening even without apparent external injuries.

Significant Mechanisms in Vehicle Accidents

• Death of another occupant.
• Severe deformity or intrusion to the vehicle.
• Moderate intrusion from a lateral accident.
• Severe rear-end damage.
• Crashes involving rotation (rollovers) and ejection.

Frontal Crashes

• Evaluate seatbelt use, airbag deployment, and restraint systems.
• Seatbelts and airbags prevent second collisions.
• Seatbelts may decrease the severity of the third collision.
• Suspect injuries to extremities and internal organs despite airbags.
• Children shorter than 4'9" should ride in the rear seat.
• Undeployed airbags can still deploy, posing a risk to rescuers.
• Seatbelts and airbags can cause injuries themselves (e.g., hip dislocations).

Rear-End Collisions

• Commonly cause whiplash-type injuries due to improperly placed headrests.
• Acceleration-type injury to the brain.
• Passengers in the back with only lap belts may have more injuries.

Lateral Crashes (T-Bone)

• Vehicle struck from the side, usually above its center of gravity.
• Passengers can experience lateral whiplash.
• Substantial intrusion possible, leading to lower extremity and pelvic fractures.
• Organ damage from the third collision.

Rollover Crashes

• Large trucks and SUVs are prone to rollovers.
• Question to ask: was the patient restrained?
• Ejection is a life-threatening event in rollovers.
• Even restrained passengers can sustain severe injuries.

Rotational Crashes (Spins)

• Similar to rollovers; vehicle rotates and strikes other objects.

Vehicle vs. Pedestrian

• Injuries may be graphic and apparent, but not always.
• Determine vehicle speed at impact and whether the patient was thrown.
• Evaluate landing surface and whether the patient was struck or pulled underneath the vehicle.
• Evaluate vehicle damage.
• ALS should be summoned for significant MOIs.

Car vs. Bicycle

• Similar to car vs. pedestrian; bicycle offers no protection.
• Evaluate damage to the bike and whether the patient wore a helmet.
• If no airway, breathing, or circulatory compromise, leave the helmet on.
• Maintain C-spine while removing the helmet if necessary.

Car vs. Motorcycle

• Bikes don't provide much protection.
• Look at damage to the motorcycle to determine likely injuries.
• Assess skid distance and deformity of stationary objects.
• Extent and location of helmet deformity.
• Categories of motorcycle crashes:
  • Head-on crash: rider thrown forward.
  • Angular crash: lateral injuries.
  • Ejection: rider thrown from the bike.
  • Controlled crash: laying the bike down to avoid a more serious crash.

Falls

• Injury potential is related to height.
• A fall from greater than 20 feet (6 meters) is considered significant.
• Internal injuries pose the greatest risk.
• Take into account height, surface, and body part that hit first.
• Follow the path of displacement.
• Landing on feet may cause lower extremity and pelvic injuries.

Penetrating Trauma

• Second leading cause of trauma-related deaths in the United States.
• Low-energy penetration: impalements, stabbings, ice picks.
  • Injuries caused by sharp edges of the object directly in its path.
  • Do not remove penetrating objects.
• Medium and high-velocity trauma: bullets, fragments from explosions.
  • The bullet may flatten, tumble, or ricochet within the body.
  • The path of the projectile is its trajectory.
  • Bullets don't travel in straight lines.
  • Look for an exit wound.

Fragmentation and Cavitation

• Fragmentation can increase damage.
• Cavitation: rapid pressure changes in tissue and fluid pressure.
  • Temporary cavity: temporary damage.
  • Permanent cavity: path that the bullet tore through.
• Air resistance (drag) slows projectile.
• The damaged area is larger than the projectile's diameter.
• Exit wounds are typically larger than entrance wounds.
• Bullet damage is more a function of speed than mass.
• The type of tissue where the projectile passes matters.

Blast Injuries

• Injuries caused by four different mechanisms:
  • Primary blast injuries: from the blast itself (pressure wave).
  • Secondary blast injuries: damage from flying debris.
  • Tertiary injuries: being thrown into something else.
  • Quaternary (miscellaneous) blast injuries: secondary events.
    • Inhaled toxic gas.
    • Respiratory distress.
    • Crush injuries from building collapse.
    • Suffocations, poisonings, eventual infection, etc.
• Most survivors experience a combination of the four types of injury.
• Organs containing air (hollow organs) are more susceptible to pressure injuries.
  • Ear is most susceptible, then lungs and gastrointestinal tract.
• Pulmonary blast injuries can cause arterial air embolism.
  • Alveolar distruption with air moving into the pulmonary system.
  • Visual disturbances, behavioral changes, altered level of consciousness and neurological symptoms.
• Solid organs are relatively protected.
• Neurological injuries and head trauma are the most common cause of death from blast injuries.

Multisystem Trauma

• Involves more than one body system.
  • head/spinal trauma, chest/abdominal trauma, bilateral extremity trauma.
• Patients can be trauma alerted.
• These patients have a high level of morbidity and mortality.

Patient Assessment and Priorities

• Safety is the top priority, then crew safety, then patient safety.
• Request law enforcement or hazmat if needed.
• Focus on patient care: hemorrhage control before ABCs (XABC).
• Maintain spinal restriction if C-spine injury is suspected.
• Lookout for signs and symptoms of shock.
• Transport critical trauma patients in under ten minutes.
• Rapid physical exam for significant MOIs.
  Rapid physical exam for significant MOIs.
• Focused assessment for non-significant MOIs.

Specific Injuries

• Head Injuries:
  • Disability and unseen injury to the brain are possible.
  • Bleeding and swelling inside the skull are life-threatening.
  • Perform frequent neurological exams(GCS) assessing mental status.
  • Some patients might have delayed signs.
• Injuries to the Head and Neck:
  • Lookout for the signs of airway compromise.
  • DCAP PTLS for JVD (Jugular Vein Distension) and tracheal deviation.
  • Swelling can prevent blood flow to the brain.
  • Penetrating injury can cause air embolism.
  • Crushing injuries to the neck can damage the larynx and upper airway.
• Chest injuries:
  • Broken ribs can hinder breathing.
  • The heart may be bruised, diminishing output.
  • The vessels/vasculature may be damaged leading to massive hemorrhaging.
  • Air or blood can collect between the lung tissue and the chest wall.
    • Pneumothorax and hemothorax.
• Open chest wound - Penetration/Perforation of the Chest.
  * Signs: Bubbling.
  * Immediate Treatment is required.
  * Cover w Gloved hand then an occlusive dressing/chest seal.
• Abdominal Injuries
  • High levels of blood flow in organs can have an effect on injuries to those organs.
    *Solid organs can tear, lacerate, or fracture. (bleeding/hemorrhage)
    *Hollow organs can rupture and leak and cause infections.

Trauma Facility Levels.

*Each facility has trauma surgeons available 24/7.
Level 1 - every aspect of trauma care(Major cities).
*Closest level 1: Pittsburg, Ruby and Baltimore.
Level 2 - Less populated areas.
*Can do some trauma interventions.
Level 3 - Assessment care, emergency, and stabilization (Garrett Co).
Level 4 - Band Aid station (Miresdale Med).

• ALS qualifications by paramedic transport.
  Extended period of time to remove traffication.
  Distance to trauma center is more than 20/25+ miles.
  ALS care is available by ground resources.
  If there is any mass casualty, and an overwhelming amount of local support.
  *Do not transfer pediatric patients to trauma patients.

Maryland Trauma Decision Tree.

*Trauma A: Show signs of Symptoms of Shock.
*Trauma B: has significant injuries (amputation, crushed).
*Trauma C: Significant mechanism (another passenger died).
*Trauma D: Just Because I said so. Old, young, preggers, burns, stroke, STEMI (Need a Helicopter.)
Transport types: Ground / Air EMS.