Trauma Systems and Mechanism of Injury

Occurs when the projectile has sufficient energy that is not entirely dissipated along its trajectory through the body; the projectile then exits the patient and can injure other bystanders as well

exit wounds

What is the difference between entrance and exit wounds?

exit wounds usually have irregular edges and may be larger than the entrance wound

In the United States, what is the most common sources of penetrating injuries?

firearms

What are the five types of impact patterns in motor vehicle crashes?

frontal, lateral, rear, rotational, and rollover

What factors determine the severity of falls?

height, position or orientation of the body at impact, area over which the impact is distributed, surface they fell onto, physical condition of the pt

When should you remove a helmet in a motorcycle crash?

if airway management techniques cannot be performed with the helmet in place or the helmet does not fit snugly to the head

How can a dangerous lung injury occur in an MVA patient?

if the patient reflexively takes a deep breath just before impact, hyperinflating the lungs and closing the glottis, the impact can injure the lungs via generation of pressures beyond the capabilities of lung tissue like a "paper bag being exploded"

A bursting inward

implosion

How should a dislocated knee be splinted in the field?

in the position found if the patient has good distal PMS

What does heavy wound contamination result from in gunshot wounds?

negative pressure generated behind the traveling projectile, which sucks surrounding elements such as clothing into the wound=infection potential

The phase of an explosion in which pressure from the blast is less than atmospheric pressure

negative wave pulse

What are the most common causes of death from blast injuries?

neurologic injuries and head trauma

What are secondary collisions in an MVA?

occur when a vehicle occupant is hit by objects moving within the auto such as packages, animals, or other passengers

What is the second impact of a pedestrian vs vehicle injury?

occurs as the adult is thrown on the hood and/or grill, resulting in head, pelvis, chest, and coup-contrecoup traumatic brain injuries

What is the third impact of a pedestrian vs vehicle injury?

occurs when the body strikes the ground or some other object after it has been subjected to a sudden acceleration by the colliding vehicle

The tissue displacement that occurs as a result of low-displacement shock waves that travek at the speed of sound in tissue

pathway expansion

The path of crushed tissue produced by a missile traversing part of the body

permanent cavity

Refers to the phase of the explosion in which there is a pressure front higher than atmospheric pressure

positive wave pulse

Energy stored in an object

potential energy

In this type of impact, a stationary or slower moving vehicle is struck from behind and the impact energy is transmitted as a sudden accerlerating force

rear-impact collision

What type of motor vehicle collision has the most survivors (if properly restrained)?

rear-impact collisions

What are the benfits of restraints in MVAs?

restraints limit the contact of the occupants with the interior of the vehicle, prevent ejection, distribute deceleration energy over a greater surface, and prevent the occupants from violently contacting each other

Occurs when the collision is off center

rotational or quarter-panel impact

What type of pellets do shotguns fire?

round pellets

When there is evidence of ear problems after an explosion, what should you look for?

serious injury to the lungs

An applied force or pressure exerted against the surface and layers of the skin as tissues slide in opposite but parallel planes

shearing

What can decelerating forces induce in organs?

shearing, avulsing, or rupture

What injuries are caused by deceleration?

shearing, avulsing, rupturing of organs; head injuries, chest (aortic) injuries, abdominal organ injuries, kidney and bowel injuries

How are pediatric patterns of pedestrian injury different than in adults?

small children are shorter, so the car bumper is more likely to strike them in the pelvis or torso, causing severe injuries from direct impact; they are also more likely to be run over by the vehicle as they are propelled to the ground by the impact rather than adults who tend to fly over the hood

Delaminating or breaking off into chips and pieces

spalling

What does the severity of a stab wound depend on?

the anatomic area involved, the depth of the penetration, blade length, and angle of penetration

The acute physiologic and structural change (injury) that occurs in a patient's body when an external source of energy dissipates faster than the body's ability to sustain and dissipate it

trauma

What are some contraindications for aeromedical transport?

traumatic cardiac arrest, inclement weather conditions, extremely combative patients, morbidly obese patients, patients with barotrauma (diving injuries), if ground transport would be quicker

The eardrum; a thin, semitransparent membrane in the middle ear that transmits sound vibrations to the internal ear by means of auditory ossicles

tympanic membrane

The amount of damage a firearm can cause will depend on what factors?

type of firearm (rifle, shotgun, handgun), velocity of projectile, physical design of projectile, the distance to the target from the muzzle of the firearm, and the type of tissue struck

Cavity formation

cavitation

What is the technique used by motorcycle riders to separate the rider from the body of the motorcycle and the object to be hit?

"laying the bike down" it is a means of achieving a controlled crash; it allows the rider to become separated from the motorcycle and prevents them from being trapped between the bike and the object

What are the 3 components of the Waddell triad?

1.) the bumper hits the pelvis and femur 2.) the chest and abdomen hit the grille or low on the hood of the car 3.) the head strikes the vehicle and then the ground

What are the two types of trauma?

Blunt or penetrating

What are secondary blast injuries?

Damage results from being struck by flying debris, such as schrapnel from the device or from glass or splinters, that has been set in motion by the explosion

What is the term for a group of potential injuries from a vertical fall to a standing position

Don Juan Syndrome or lover's leap

What are primary blast injuries?

Due entirely to the blast itself , that is, damage to the body caused by the pressure wave generated by the explosion

What is the most important factor for the seriousness of a gunshot wound?

the type of tissue through which the projectile passes

States that a body at rest will remain at rest unless acted on by an outside force

Newton's first law of motion

States that the force that an object can exert is the product of its mass times its acceleration (or deceleration)

Newton's second law of motion

The governing body responsible for the designation of trauma centers

The Committee on Trauma (COT)

What are miscellaneous blast injuries?

These include burns from hot gases or fires started by the blast, respiratory injury from inhaling toxic gases, and crush injury from the collapse of buildings

What are tertiary blast injuries?

These occur when the patient is hurled by the force of the explosion against a stationary object

A pattern of automobile-pedestrian injuries in children and people of short stature in which 1.) the bumper hits the pelvis and femur, 2.) the chest and abdomen hit the grille or low hood, and 3.) the head strikes the ground

Waddell triad

In what situations should air tansport be considered vs ground transport?

When there is extended transport time by ground, when there are multiple casualties, when extrication times are prolonged and patients are critically injured, when there are long distances to an appropriate facility as opposed to the closest ED, is there a safe area for landing?

What height has a greater incidence of morbidity and mortality for a fall?

a fall greater than 15 feet or three times the patient's height

What are abrupt deceleration injuries caused by?

a sudden stop of a body's forward motion

What are common injuries associated with air bag use?

abrasions and burns to the face, chest, and arms, minor corrosive toxic effects, chemical keratitis, conjunctivitis, or corneal abrasion and inhalation injuries

The rate of change in velocity

acceleration

A respiratory syndrome characterized by respiratory insufficiency and hypoxemia

acute respiratory distress syndrome (ARDS)

What organs are most susceptible to pressure changes?

air-containing organs such as the middle ear, lung, and GI tract

What are factors that affect types of injury?

amount of force and energy delivered, size (mass) of objects delivering the force and energy, velocity, body area, duration, direction, rate of application, position of trauma victim, impact resistance of body parts, densities of tissues

In this type of collision, the motorcycle strikes an object or another vehicle at an angle so that the rider sustains direct crushing injuries to the lower extremity between the object and the motorcycle

angular collision

What is one of the most concerning pulmonary blast injuries?

arterial air embolism

A tearing away or forcible separation

avulsing

The energy that results from sudden changes in pressure (diving or flying)

barometric energy

The study of the physiology and mechanics of a living organism using the tools of mechanical engineering

biomechanics

The leading edge of the shock wave

blast front

What injuries may result from compression against the seat-belt?

bowel rupture, bladder rupture, diaphragm tearing, and spinal injuries

What are injuries caused by crush and compression?

brain injury, fractured ribs, flail chest, blunt cardiac injury, acute respiratory distress syndrome (ARDS), abdominal organs, pelvic fractures

Which tissues of the body are relatively inelastic, in which the temporary cavity may become a permanent defect?

brain, liver, spleen

The shattering effect of a shock wave and its ability to cause disruption of tissues and structures

brisance

How do children tend to fall differently than adults?

children tend to fall head first and adults try to land on their feet

What is the difference between crush and deceleration injuries?

crush injuries occur at the time of impact and deceleration injuries occur before impact

What are the five phases of trauma in a motor vehicle collision?

deceleration of the vehicle, decleration of the occupant, deceleration of internal organs, secondary collisions, additional impacts

Unrestrained occupants of an MVA usually follow one of which two trajectories?

down-and-under pathway or up-and-over pathway

What does the size of the exit wound depend on?

energy dissipated and the degree of cavitation at the point of exit

The energy associated with bodies in motion, expressed mathematically as half the mass times the square of velocity

kinetic energy

The energy associated with that object in motion

kinetic energy (KE)

The study of the relationship among speed, mass, vector direction, and physical injury

kinetics

In which impact of an MVA do seatbelts do little to protect the passengers?

lateral impact because seatbelts are designed to limit forward hinging injuries, not side impacts

What is the highest level trauma center?

level 1

When the auto strikes and adult body with its bumper, what injuries does it create?

lower extremity injuries, particularly to the knee and leg

Energy from motion (kinetic energy) or that is stored in an object (potential energy)

mechanical energy

This is a major cause of tissue damage in which the projectile sends off fragments that create their own separate paths through tissues

missile fragmentation

Which tissues of the body are relatively elastic, resulting in fewer permanent effects of temporary cavitation?

muscle, bowel, and lung

What is the most common site of deceleration injury in the chest?

the aorta

What is the danger of deceleration injuries to the aorta?

the aorta is often torn away from its points of fixation in the body; this shearing of the aorta can result in rapid loss of all the body's blood and immediate death

When you are assessing the scene of a motorcycle crash, what should attention be given to?

the deformity of the motorcycle, the side of most damage, the distance of skid in the road, the deformity of stationary objects or other vehicles, and the extent and location of deformity in the helmet

What organ system is the most sensitive to blast injuries?

the ear

What is the general rule regarding entrance and exit wounds in penetrating trauma?

the entrance wound is always smaller than the exit wound

What does the platinum ten minutes refer to?

the goal of the max time spent at a scene for a critical trauma patient

In the up-and-over pathway in an MVA, what is the lead point of the patient?

the head

What body part is particularly vulnerable to deceleration injuries?

the head

In the down-and-under pathway in an MVA, what is the lead point of the patient?

the knees

States that energy can be neither created nor destroyed, it can only change form

the law of conservation of energy

In a lateral impact collision, where is energy to the near-side occupant almost directly imparted to?

the pelvis and chest

What will dents and deformities on the inside of a vehicle show you?

the point of impact on the patient

The speed, duration, and pressure of the shock wave are affected by what?

the size of the explosive charge, the nature of the surrounding medium (water, air, etc), the distance from the explosion, the presence of absence of refleting surfaces

The distance an object travels per unit of time

velocity

Which has a greater effect on kinetic energy, velocity or weight?

velocity

What is the difference between speed and velocity?

velocity is defined by moving in a specific direction

To give the trauma team at the hospital as much information as possible regarding a firearm injury, what information should you try and obtain?

what kind of weapon was used, at what range was it fired, what kind of bullet was used

What do tire skid marks at the scene indicate?

whether significant energy was dissipated by braking before collision

An injury to the cervical vertebrae or their supporting ligaments and muscles, usually resulting from sudden acceleration or deceleration

whiplash