Chapter 27 Trauma Overview: The Trauma Patient and the Trauma System Notes

Case Study: Hunting Accident in Remote Area

  • Incident Overview:

    • EMTs Nina Segall and Scotty Lindquist respond to a report of a person shot in a hunting accident.

    • Response Time: The EMTs had a 15min15\,min response time to a remote area.

    • Scene Safety: State police confirmed the scene was safe and all weapons were secured.

    • Patient Profile: A 2727-year-old male accidentally shot by another hunter with a high-velocity rifle.

  • Initial Assessment:

    • Scene Size-up: A police officer is holding direct pressure on the patient's thigh.

    • Patient Presentation: The patient is lying supine on the ground.

    • Mental Status: The patient appears combative and confused.

    • Skin Condition: Pale and sweating, despite cool environmental temperatures.

    • Vital Signs: Nina detect a weak, thready radial pulse estimated to be > 100\,beats/min.

    • Airway and Breathing: The airway is open; breathing is adequate. Oxygen is applied via a nonrebreather mask.

  • Secondary Assessment:

    • Rapid Secondary Assessment: Nina identifies an entry wound on the front of the thigh and an exit wound posteriorly.

    • Preparation: Scotty prepares a long backboard for transport.

  • Outcome and Disposition:

    • Destination Decision: There is a community trauma center 20min20\,min away and a regional trauma center 70min70\,min away.

    • Medical Direction: Advised transport to the community trauma center for initial stabilization, with a likely subsequent transfer to the regional trauma center for definitive treatment.

The Kinetics of Trauma

  • Definitions:

    • Mechanism of Injury (MOI): The process or method by which a person is injured.

    • Kinetics: This is the branch of mechanics dealing with the movements of bodies. It is the science used to analyze the mechanism of injury.

  • Key Factors in Kinetics:

    • Mass and Velocity: These are the primary determinants of kinetic energy.

    • Kinetic Energy Formula: Velocity is a more significant factor than mass. The energy involved is calculated as:       KE=12mv2KE = \frac{1}{2}mv^2       where mm is mass and vv is velocity.

    • Assessment Tip: Estimating the speed of objects involved in motor vehicle collisions or penetrating trauma is vital for predicting injury severity.

  • Acceleration and Deceleration Laws:

    • Law of Inertia: A body at rest remains at rest, and a body in motion remains in motion unless acted upon by an outside force.

    • Rate of Change: A faster change of speed (acceleration or deceleration) results in more force exerted on the body.

  • Energy Transformation:

    • Energy travels in a straight line unless it meets interference.

    • Interference causes kinetic energy to change direction or form (e.g., from motion into heat or tissue deformation).

Impact Types in Vehicle Collisions

  • The Three Impacts: In a typical motor vehicle collision, energy is absorbed in three distinct stages:

    1. Vehicle Collision: The vehicle strikes an object (e.g., an automobile hitting a tree).

    2. Body Collision: The occupant continues moving forward due to inertia and strikes the interior of the automobile (e.g., hitting the steering wheel or dashboard).

    3. Organ Collision: Internal organs continue moving forward and strike the inside of body cavities (e.g., the brain striking the skull, or the heart striking the sternum/ribs).

Mechanisms of Injury (MOI) in Vehicle Collisions

  • Indicators of High-Risk Injury: A high suspicion of injury should be maintained if any of the following are present:

    • Death of another vehicle occupant.

    • Altered mental status.

    • Intrusion of the vehicle over 12inches12\,inches into the occupant site.

    • Ejection from the vehicle.

    • Vehicle telemetry data indicating a high risk of injury.

  • Frontal Impact Pathways:

    • Up-and-Over Pathway: The occupant moves upward over the steering wheel. Injuries occur to the head, neck, face, chest, and abdomen.

    • Down-and-Under Pathway: The occupant moves downward under the dashboard. Injuries occur to the knees, femurs, hips, acetabulum, and spine.

    • "Paper Bag" Syndrome: Compression of the chest against the steering column occurs while the patient has a closed glottis, causing the lungs to pop like a paper bag.

  • Rear-End Impact:

    • Initially, the head and neck are whipped back (hyperextension).

    • Properly adjusted headrests and seat belts reduce these injuries.

    • Subsequent motion can lead to up-and-over or down-and-under pathways.

  • Lateral (Side) Impact:

    • Injuries occur to the side of the body struck.

    • Impacts often involve the head, neck, shoulder, lateral chest, lateral abdomen, lateral pelvis, and femur.

  • Rotational and Rollover Crashes:

    • Injury patterns are less predictable.

    • Rollovers involve multiple impacts and changes in direction.

    • Ejection is common; ejected occupants are frequently crushed.

    • These crashes carry a high risk of multisystem trauma.

Specific Mechanisms: Pedestrians, Restraints, and Specialized Vehicles

  • Vehicle-Pedestrian Collisions: Severity depends on:

    • Vehicle speed.

    • Body part hit.

    • Distance the pedestrian was thrown.

    • Landing surface and initial impact point on the ground.

    • Differences exist between child and adult injury patterns (children are often run over, whereas adults are often thrown up onto the hood).

  • Restraint Systems:

    • Benefits outweigh the risks, but improper use can cause hidden injuries.

    • Lap belts and shoulder straps must be positioned correctly over the pelvis and shoulder.

    • Air bags are not designed for secondary collisions.

  • Infants and Children in Vehicles:

    • Head and neck are not secured; the head snaps forward straining the neck.

    • Spinal cord injury can occur without visible vertebrae damage.

    • Car seats should only be placed in the backseat.

  • Motorcycles and ATVs:

    • Motorcycles: Helmets significantly reduce morbidity/mortality. Injuries result from head-on impacts, angular impacts, or ejection. "Laying the bike down" causes severe abrasions and burns.

    • ATVs: Highly unstable and easily tipped. Impacts are similar to motorcycle collisions but with added crushing risks from the vehicle itself.

Falls

  • Severity Factors:

    • Distance of the fall.

    • Surface landed on.

    • Body part that impacted first.

  • Critical Fall Heights:

    • Adults: Severe if > 20\,ft.

    • Children: Severe if > 10\,ft or two to three times the child's height.

  • Fall Mechanics:

    • Feet-First Falls: Energy is transmitted up the skeletal system. Common injuries: lower extremities, spine, internal organs, and wrists/elbows (if arms were used to break the fall).

    • Head-First Falls: Upper extremity, head, neck, chest, spine, and pelvis injuries.

Penetrating Injuries

  • Velocity Categories:

    • Low-Velocity: Knives or similar objects. Damage is usually limited to the path of the object. Defensive slash wounds are possible.

    • Medium-Velocity: Shotguns and handguns.

    • High-Velocity: Rifles. These cause massive injury due to cavitation.

  • Energy Dissipation Factors:

    • Drag: Air resistance on the projectile.

    • Profile: The surface area of the projectile pointing forward.

    • Cavitation: The pressure wave creates a temporary cavity in the tissues much larger than the projectile diameter.

    • Fragmentation: The projectile breaks into smaller pieces, increasing damage.

  • Gunshot Statistics:

    • 90%90\% of fatal wounds involve the head, thorax, and abdomen.

Blast Injuries

  • Primary Phase (Pressure Wave): Air molecules slam into one another. The pressure wave causes injuries to hollow, air-filled organs (lungs, ears, GI tract).

  • Secondary Phase (Blast Wave): Pieces of the bomb casing or other projectiles strike the patient.

  • Tertiary Phase (Patient Displacement): The blast wind propels the patient to the ground or against objects.

  • Quaternary/Quinary Phase: Exposure to chemicals, toxins, or structural collapse.

Management of Multisystem Trauma

  • The Multisystem Trauma Patient: Patients with injuries to multiple body systems have higher morbidity/mortality rates. Care focuses on managing immediate life threats and rapid transport.

  • The Golden Principles:

    • Personal safety is the highest priority.

    • Maintain airway and adequate ventilation/oxygenation.

    • Control significant external bleeding.

    • Perform assessments in a systematic sequence.

    • Use a backboard to splint fractures in unstable patients.

    • Avoid "tunnel vision" on dramatic injuries.

  • The Golden Period and Platinum 10 Minutes:

    • Best survival occurs with rapid intervention.

    • EMS goal: Limit scene time to 10min10\,min or less for severely injured patients.

  • Indications for Rapid Transport (10min\le 10\,min Scene Time):

    • Airway/Respiratory: Occlusion, Rate < 10 or > 29/min, inadequate tidal volume, hypoxia, respiratory failure.

    • Head/Neurological: Suspected skull/brain injury, GCS 13\le 13, altered mental status, seizures, paralysis, sensory/motor deficits.

    • Circulation/Bleeding: Shock signs, uncontrolled external hemorrhage, suspected internal hemorrhage.

    • Specific Anatomical Injuries:

      • Flail chest, suspected pneumothorax/tension pneumothorax.

      • Pelvic fracture.

      • Two or more proximal long-bone fractures.

      • Crushed or mangled extremity.

      • Amputation proximal to the finger.

      • Penetrating trauma to the head, neck, torso, or proximal extremities (above elbow/knee).

    • Special Populations: Multisystem trauma, trauma in pregnancy, patients over 5555, or those with significant medical history (MI, COPD, CHF).

The Trauma System and Triage

  • Trauma Center Levels:

    • Level I: Regional Trauma Center.

    • Level II: Area Trauma Center.

    • Level III: Community Trauma Center.

    • Level IV: Trauma Facility.

  • Triage Guidelines (ACS-COT 2022):

    • Red Criteria: High risk for serious injury; requires transport to the highest level trauma center.

    • Yellow Criteria: Moderate risk for serious injury.

Questions & Discussion

  • What are the priorities in managing the case study patient?

    • Response: Airway management, ensuring adequate breathing, administering oxygen, and controlling the femoral hemorrhage while preparing for rapid transport due to signs of shock (tachycardia and altered mental status).

  • What information will help determine the extent of the patient's injuries?

    • Response: Understanding the MOI (high-velocity rifle), the location of entry and exit wounds, and the patient's clinical signs of shock.

  • What factors should EMTs consider in determining transport destination?

    • Response: The level of surgical capability required, distance to specialized trauma centers, and medical direction guidance.