The Many Faces of Trauma

Today’s Discussion Kinematics of trauma forces involved with the transfer of energy kinematics of different types of trauma Energy is neither created nor destroyed; however, it can be changed in form

Definitions Kinetic energy - the energy contained in a moving body Kinetic energy is equal to mass multiplied by velocity squared divided by two Therefore, of the two factors, which has the greater impact on amount of damage; mass or velocity?

The Rules of Kinematics A body in motion or a body at rests tends to remain in that state until acted on by an outside force This is the law of inertia Force equals mass times deceleration (acceleration) This means that the rate at which something speeds up or slows down also impacts the degree of damage done in an accident

Types of Impacts Primary Impact - (vehicular collision) something the patient is in impacts an object Secondary Impact - (body collision) patient’s body strikes something in the vehicle Tertiary Impact - (organ collision) internal organ strikes a rigid object within the body

Blunt Trauma Vehicular Impact Pedestrian Impact Motorcycle Crashes Assaults Falls Blasts

Types of Injury Categories Compression paper bag syndrome to lungs Deceleration renal pedicle, ligamentum teres, descending aorta stop while mobile organs continue forward movement Restraint injury occasional cardiac contusion, broken clavicle patient would have died without the seatbelt

Frontal Impact Pattern Down and under fx/dis of knee/ankle Femur fx posterior dislocation of acetabulum Up and over head injury chest injury

Rear Impact Most commonly occurs when vehicle is at a complete stop Without proper headrest position, head does not accelerate with body Frontal impact often occurs if car is in a line of vehicles

Other impacts Rollover Ejection Patient can impact any part of vehicle Best indicator is impact points found on skin As a rule, more serious because of the multiple and violent motions involved Ejection Injuries from ejection may be greater than from ground impact Likelihood of injury is increased by 300% over patient that is not ejected

Pedestrian Injuries Three phases of impact Frontal vehicular bumper Vehicular hood and windscreen Ground In pediatrics the pattern is different and depends on the size of the patient

Pedestrian Injury Triad

Motorcycle Collisions Frontal impact head and chest may impact handlebars femurs hit handlebars Lateral crush injuries to extremities ejection injuries from ground impact Laying down the bike causes rider to move slower than bike avulsions, abrasions, burns

Falls and Blasts Blasts are caused by rapidly expanding gases Primary injuries direct injury to gas containing organs Secondary injuries flying debris Tertiary injuries individual becomes a missile and is thrown against solid objects

Cavitation Definition: energy transfer which occurs when body tissue cells are placed in motion directly away from the site of impact by the energy exchange

Size of Cavitation Determined by: amount of energy exchanged which is determined by number of tissue particles impacted which is determined by the density of the tissue Larger the surface area and denser the tissue, the more particles affected. The reverse is also true

Penetrating Trauma Factors affecting cavitation at the wound impact point Shape of the missile tumble and yaw Fragmentation Maximum velocity of a lead bullet is 2000 f/sec Kinetic Energy = mass x velocity

Bullet Velocities Kinetic Energy = mass x velocity High energy bullets may cavitate 30 times greater than the diameter of the missile

Entrance vs. Exit Entrance Exit Only two sure signs, powder burns, or only one hole Hints round or oval wound gases beneath skin (close range) burns (weapon inches from skin) stippling (weapon 4-6 inches from skin) Exit Usually stellate shape No other distinguishing features

Trauma Assessment Starts with a Story

Final Thought Plan for the worst and you will never be surprised or disappointed