Trauma Overview and Pre-Hospital Care

Chapter 25. Trauma Overview. Introduction. According to the National Center for Health Statistics, traumatic injuries and unintentional injuries are the leading causes of death in the United States among people from 1 to 44 years of age. Proper pre-hospital evaluation and care has the capability to reduce a patient's suffering, long-term disability, and risk of death from trauma. Patients who need emergency medical service assistance are generally categorized as either a medical or trauma emergency, although one may result from the other or both may exist. This is discussed further in Chapter 15, Medical Overview. Trauma emergencies occur as a result of physical forces applied to the body. Medical emergencies include illnesses or conditions. These are not caused by an outside force. Traumatic injuries may be caused by underlying medical conditions. A patient has a stroke and veers off the road, striking a tree. Similarly, medical illnesses may result from recent or remote traumatic injuries. Pneumonia develops in a patient a few days after a fall that fractured the patient's ribs. This chapter introduces the basic physical concepts that dictate how traumatic injuries occur and how they affect the human body. When you understand these concepts, you'll be better prepared to size up a vehicular crash scene and assess a patient. This chapter begins with the basic discussion of energy and trauma. Next, different types of vehicle crashes, and their effect on the body are explained. By assessing a vehicle that has crashed, you can often determine what happened to the passengers at the time of impact. This may allow you to predict what injuries the passengers sustained at the time of impact. Evaluation of the mechanism of injury for the trauma patient will provide you with an index of suspicion for different types of serious and or life-threatening underlying injuries. Certain injury patterns occur with certain types of injury events. The index of suspicion is your awareness and concern for potentially serious underlying and unseen injuries. Energy and Trauma Traumatic injury occurs when the body's tissues are exposed to energy levels beyond their tolerance. The mechanism of injury is the way in which traumatic injuries occur. It describes the forces, or energy transmission, acting on the body that cause injury. Three concepts of energy are typically associated with injury, not including thermal energy, which causes burns, potential energy, kinetic energy, and the energy of work. When considering the effects of energy on the human body, it is important to remember that energy can be neither created nor destroyed. It can only be converted or transformed. It is not the objective of this section to help you reconstruct the scene of a motor vehicle crash. Rather, you should have a sense of the effects of the event on the human body, and understand, in a broad sense, how that event is related to potential and kinetic energy. For example, when assessing a patient who fell, you need not calculate the speed at which the person hit the ground. Instead, focus on the factors of the impact. and how those relate to the potential for injury. For example, it is important to estimate the height from which the patient fell, as well as the surface he or she landed on, to fully appreciate the injury potential of the fall. Work is defined as force acting over a distance. For example, the force needed to bend metal multiplied by the distance over which the metal is bent is the work that crushes the front end of a vehicle that is involved in a frontal impact. Similarly, forces that bend pull or compressed tissues beyond their inherent limits result in the work that causes injury the energy of a moving object is called kinetic energy kinetic energy reflects the relationship between the mass weight of the object and the velocity speed at which it is traveling kinetic energy is expressed as kinetic energy equals one-half mass times velocity squared or kinetic energy equals one-half of a meter times V squared remember Energy cannot be created or destroyed, only converted. In the case of a motor vehicle crash, the kinetic energy of the speeding vehicle is converted into the work of stopping the vehicle, usually by crushing the vehicle's exterior. Similarly, the passengers of the vehicle have kinetic energy because they were traveling at the same speed as the vehicle. Their kinetic energy is converted to the work of bringing them to a stop. It is this work on the passengers that results in injury. Notice that, according to the equation for kinetic energy, the energy that is available to cause injury doubles when an object's weight doubles but quadruples when its speed doubles. When a car's speed increases from 50 to 70 miles per hour, the energy that is available to cause injury nearly doubles. This point is even clearer when considering gunshot wounds. The speed of the bullet, high velocity compared with low velocity, has a greater impact on producing injury than the mass, size, of the bullet. Therefore, it is important to report to the hospital the type of firearm that was used in a shooting. The amount of kinetic energy that is converted to do work on the body dictates the severity of the injury. High energy injuries often produce such severe damage that patients require immediate transport to an appropriate facility to have any hope of survival. Potential energy is the product of mass, weight, force of gravity, and height and is mostly associated with the energy of falling objects. A worker on a scaffold has potential energy because he or she is some height above the ground. If the worker falls, potential energy is converted into kinetic energy. As the worker hits the ground, The kinetic energy is converted into work, that is, the work of bringing the body to a stop, and thereby fracturing bones and damaging tissues. Mechanism of Injury Profiles Different types of mechanism of injuries will produce many types of injuries. Examples of non-significant injuries include injury to an isolated body part or a fall without the loss of consciousness. Examples of significant mechanism of injuries include injury to more than one body system. Multi-system trauma, falls from heights, motor vehicle and motorcycle crashes, car versus pedestrian, or bicycle or motorcycle, gunshot wounds, and stabbings. Whether one or more body systems are involved, maintain a high index of suspicion for serious unseen injuries. Blunt and penetrating trauma. Traumatic injuries can be considered in two categories, blunt trauma and penetrating trauma. Blunt trauma is the result of force. or energy transmission, to the body that causes injury without anything penetrating the soft tissues or internal organs and cavities. Penetrating trauma results in injury by objects that pierce and penetrate the surface of the body, and injure the underlying soft tissues, internal organs, and body cavities. Either type of trauma may occur from a variety of mechanism of injuries. It is important to consider unseen as well as visible, obvious injuries with either type of trauma. Damage to the underlying deeper tissues is often more significant. Blunt trauma. Blunt trauma results from an object making contact with the body. Any object, such as a baseball bat, can cause blunt trauma if it is moving fast enough. Motor vehicle crashes and falls are two of the most common mechanism of injuries for blunt trauma. When providing care for your patient, be alert to signs of skin discoloration or reports of pain because these may be the only signs of blunt trauma. During assessment, maintain a high index of suspicion for hidden injuries in patients with blunt trauma. Vehicular crashes Motor vehicle crashes are traditionally classified as frontal, head-on, rear-end, lateral, T-bone, rollover, and rotational . The principal difference among these crash types is the direction of the force of impact. Also, with spins and rollovers, There is the possibility of multiple impacts. Motor vehicle crashes typically consist of a series of three collisions. Understanding the events that occur during each one of these three collisions will help you be alert for certain types of injury patterns. The three collisions in a typical impact are as follows. 1. The collision of the car against another car, a tree, or some other object. Damage to the car is perhaps the most dramatic part of the collision. but it does not directly affect patient care, except possibly to make extrication difficult. However, it does provide information about the severity of the collision, and therefore has an indirect effect on patient care. The greater the damage to the car, the greater the energy that was involved and, therefore, the greater the potential to cause injury to the patient. By assessing the vehicle that has crashed, you can often determine the mechanism of injury. which may allow you to predict what injuries may have happened to the passengers at the time of impact according to forces that acted on their bodies. When you arrive at the crash scene, and perform your scene size up, quickly inspect the severity of damage to the vehicle or vehicles. If there is significant damage to a vehicle, your index of suspicion for the presence of life-threatening injuries should automatically increase. A great amount of force is required to crush, and deform a vehicle. cause intrusion into the passenger compartment, tear seats from their mountings, and collapse steering wheels. Such damage suggests the presence of high-energy trauma. 2. The collision of the passenger against the interior of the car. Just as the kinetic energy produced by the vehicle's mass and velocity is converted into the work of bringing the vehicle to a stop, the kinetic energy produced by the passenger's mass and velocity is converted into the work of stopping his or her body. Just like the obvious damage to the exterior of the car, the injuries that result are often dramatic and usually immediately apparent during your scene size-up or primary assessment. Common passenger injuries include lower extremity fractures, knees into the dashboard, rib fractures, rib cage into the steering wheel, and head trauma, head into the windshield. Such injuries occur more frequently if the passenger is not restrained. But even when the passenger is restrained with a properly adjusted seat belt, injuries can occur, especially in lateral and rollover impacts. 3. The collision of the passenger's internal organs against the solid structures of the body. The injuries that occur during the third collision may not be the only ones. be as obvious as external injuries, but they are often the most life-threatening. For example, as the passenger's head hits the windshield, the brain continues to move forward until it comes to rest by striking the inside of the skull. This results in a compression injury to the anterior portion of the brain, and a tension injury of the posterior portion of the brain. This is an example of a coup-contre-coup brain injury. Traumatic aortic transaction or rupture is associated with a sudden and rapid deceleration of the heart and the aorta within the thoracic cavity, which may rupture the aorta and cause fatal bleeding. Understanding the relationships among the three collisions will help you make the connections between the amount of damage to the exterior of the vehicle and potential injury to the passenger. For example, in a high-speed crash that results in massive damage to the vehicle, you should suspect serious injuries to the passengers. Even if the injuries are not readily apparent, several potential physical problems may develop as a result of traumatic injuries. Your initial general impression of the patient and evaluation of the mechanism of injury can help direct life-saving care and provide critical information to the hospital staff. Therefore, if you see a contusion on the patient's forehead and the windshield is starred and pushed out, you should strongly suspect an injury to the brain. After you inform medical control about the damage to the windshield, hospital staff can prepare for the patient by being ready to perform a computed tomography scan of the brain. Without your input, the physician might have found the brain injury anyway, but it might not have been detected until the brain had swollen sufficiently to cause clinical signs of the injury. Whenever there is a significant impact to the head, also suspect a spinal injury, and take cervical spine precautions if indicated. The amount of damage considered significant varies, depending on the type of crash, but any substantial deformity of the vehicle should be enough cause for you to consider transporting the patient to a trauma center. Significant mechanism of injuries are suggested by the following findings. Death of an occupant in the vehicle. Severe deformity of the vehicle or intrusion into the vehicle. Severe deformities of the frontal part of the vehicle, with or without intrusion into the passenger compartment. Moderate intrusions from a lateral, T-bone, type of accident. Severe damage from the rear. Crashes in which rotation is involved. Rollovers and spins. Ejection from the vehicle. Damage to the vehicle that was involved. And information obtained during the scene size-up are not the only clues you can use to determine crash severity. Clearly, if one or more of the passengers are dead, you should suspect that the other passengers have sustained serious injuries. even if the injuries are not obvious. Therefore, focus on treating life-threatening injuries and providing rapid transport to a trauma center, because these passengers have likely experienced the same amount of force that caused the death of the others. Digital photos of the crash scene may provide valuable information to the staff and treating physicians at the trauma center. However, photos should be shown or transmitted only to appropriate personnel and should never be shared over social media. Photos containing patient images or other identifiable patient information may become part of the medical record or may need to be deleted after review by the receiving health care providers, depending on protected health information policies developed by the department privacy officer. Frontal crashes. Understanding the mechanism of injury after a frontal crash first involves evaluation of the supplemental restraint system, including seatbelts and airbags. Determine whether the passenger was restrained by a full and properly applied three-point restraint. Also determine whether the airbag was deployed. Identifying the types of restraints used and whether airbags were deployed will help you identify injury patterns related to the supplemental restraint systems. When properly applied, seatbelts are successful in restraining the passengers in a vehicle and preventing a second collision inside the motor vehicle. According to the Centers for Disease Control and Prevention, seatbelt use saved an estimated 15,000 lives in 2016. Seat belts may also decrease the severity of the third collision, that of the passenger's organs with the chest or abdominal wall. The protective abilities of seat belts are further enhanced by deployment of the airbags. Airbags provide the final capture point of the passengers, and decrease the severity of deceleration injuries by allowing seat belts to be more compliant and by gently cushioning the occupant as the body slows, or decelerates. Remember that airbags decrease injury to the chest, face, and lower back. and head very effectively. However, you should still suspect that other serious injuries to the extremities, resulting from the second collision, and to internal organs, resulting from the third collision, have occurred. Airbags have been standard equipment in most motor vehicles since 1999. These safety devices enhance the safety and survival of forward-facing occupants inside the vehicle during a crash, in an emergency braking event, or crash. the airbag inflates very quickly because a rear-facing car seat is in proximity to the dashboard rapid inflation of the airbag could cause serious injury or death to an infant all children who are shorter than four feet nine inches 145 centimeters should ride in the rear seat or in the case of a pickup truck or other single-seated vehicle the airbag should be turned off when providing care to an occupant inside a motor vehicle It is important to remember that if the airbag did not inflate during the accident, it may deploy during extrication. If this occurs, you may be seriously injured. Extreme caution must be used when extricating a patient in a vehicle with an airbag that has not deployed. Supplemental restraint systems can also cause harm depending on whether they are used properly or improperly. For example, some older vehicle models have seat belts that buckle automatically at the shoulder but require the passengers to buckle the lap portion. Not buckling the lap portion can cause the occupant to travel down and under the shoulder strap as the body continues forward, resulting in the lower body striking the dashboard. This movement of the body can cause the lower extremities and the pelvis to crash into the dashboard because that part of the body is unrestrained. Feet belts may also cause unseen abdominal injuries, particularly in pediatric patients. Seatbelts are designed to be worn over the iliac crests of the pelvis to distribute the force over the bony surface. Hip dislocations may result if seatbelts are worn too low. Internal injuries can occur when the belt is worn too high, resulting in damage to abdominal organs. Lumbar spine fractures are also possible, particularly in children and older patients. When passengers are riding in vehicles equipped with airbags but are not restrained by seatbelts, They are often thrown forward in the act of emergency braking. As a result, they come into contact with the airbag and or the doors at the time of deployment. This mechanism of injury is also responsible for some severe injuries to children who are riding unrestrained in the front seats of vehicles, unrestrained passengers, and those sitting too close to the airbag. Today's motor vehicles often have multiple airbags and side curtains. These are designed to protect the occupants of the vehicle. but can also alter injury patterns. Certain areas of a vehicle's body may have airbags that will deploy when impacted. Pushing on or using extrication tools in those areas may cause airbags to unexpectedly deploy. This can happen even after the car battery has been disengaged. In addition, some passengers may pass out before impact, and you may find them lying against the deployed airbag. When you encounter these types of situations, Look for abrasions and or traction type injuries on the face, lower part of the neck, and chest. Contact points are often obvious as you perform a simple, quick evaluation of the interior of the vehicle. If there is no intrusion into the passenger compartment, you might see that an unrestrained front seat passenger in a frontal crash has come into contact with the dashboard or the instrument panel at the knees, thus transferring loads from the knees through the femur to the pelvis and hip joint. The chest and or abdomen may also hit the steering wheel. In addition, the passenger's face often hits the steering wheel, or the passenger may launch forward and up, hitting the windshield and or the roof header in the area of the visors. Signs of most of these injuries can be found by inspecting the interior of the vehicle during extrication of the patient. Rear-end crashes. Rear-end impacts are known to cause whiplash injuries, particularly when the passenger's head and or neck is not restrained by an appropriately placed headrest. On impact, the passenger's body and torso move forward. As the body is propelled forward, the head and neck are left behind because the head is relatively heavy. and they appear to be whipped back relative to the torso. As the vehicle comes to rest, the unrestrained passenger moves forward, striking the dashboard. In this type of crash, the cervical spine, and surrounding area may be injured. The cervical spine is less tolerant of damage when it is bent back. Headrests decrease extension of the head and neck during a crash and, therefore, help reduce injury. Other parts of the spine and the pelvis may also be at risk for injury. In addition, the patient may sustain an acceleration injury to the brain, that is, the third collision of the brain within the skull. Passengers in the backseat wearing only a lap belt might have a higher incidence of injuries to the thoracic and lumbar spine. Lateral crashes. Lateral or side impacts, commonly called T-bone crashes, are a common cause of death associated with motor vehicle crashes. When a vehicle is struck from the side, it is typically struck above its center of gravity, and begins to rock away from the side of the impact. This results in the passenger sustaining a lateral whiplash injury. The movement is to the side, and the passenger's shoulders and head whip toward the intruding vehicle. This action may thrust the shoulder, thorax, and upper extremities, and, more important, the skull against the doorpost or the window. The cervical spine has little tolerance for lateral bending. If there is substantial intrusion into the passenger compartment, suspect your patient to have lateral chest and abdomen injuries on the side of the impact, as well as possible fractures of the lower extremities, pelvis, and ribs. In addition, the organs within the abdomen are at risk because of a possible third collision, according to the Journal of Safety Research. Lateral crashes cause approximately 25% of all severe injuries to the aorta, and approximately 30% of all fatalities that occur in motor vehicle crashes. Rollover crashes. Certain vehicles, such as large trucks, and some sport utility vehicles, are more susceptible to rollover crashes because of their high center of gravity. Injury patterns that are commonly associated with rollover crashes differ, depending on whether the passenger was restrained or unrestrained. The most unpredictable types of injuries are caused by rollover crashes in which an unrestrained passenger may have sustained multiple strikes within the interior of the vehicle as it rolled one or more times. The most common life-threatening event in a rollover is ejection or a partial ejection of the passenger from the vehicle. Passengers who have been ejected may have struck the interior of the vehicle many times before ejection. The passenger may also have struck several objects, such as trees, a guardrail. or the vehicle's exterior, before landing. Passengers who have been partially ejected may have struck both the interior and exterior of the vehicle, and may have been sandwiched between the exterior of the vehicle, and the environment as the vehicle rolled. Ejection and partial ejection are significant mechanism of injuries. In these cases, prepare to care for life-threatening injuries. Even when restrained, passengers can sustain severe injuries during a rollover crash. Although the patterns of injury tend to be more predictable, and when the restraint system is properly used, ejection from the vehicle is less likely. A passenger on the outboard side of a vehicle that rolls over is at high risk for injury because of the centrifugal force. The patient is pinned against the door of the vehicle. Rollover crashes can also cause injury when the roof of the vehicle hits the ground during the rollover. A passenger who is restrained can still move far enough toward the roof to make contact and sustain a spinal cord injury. Therefore, rollover crashes are dangerous for both restraint and, to a greater degree, unrestrained passengers because these crashes provide multiple opportunities for second and third collisions. Rotational crashes Rotational crashes, spans, are conceptually similar to rollovers. The rotation of the vehicle as it spins provides opportunities for the vehicle to strike objects such as utility poles. For example, as a vehicle spins and strikes a pole, the passengers experience not only the rotational motion, but also a lateral impact. Car vs. Pedestrian Car vs. Pedestrian crashes often result in patients who have graphic and apparent injuries, such as broken bones, however. This type of crash can cause serious unseen injuries to underlying body systems. Therefore, you must maintain a high index of suspicion for unseen injuries. A thorough evaluation of the mechanism of injury is critical. First, estimate the speed of the vehicle that struck the patient. Next, determine whether the patient was thrown, what surface the patient landed on, and at what distance or whether the patient was struck and pulled under the vehicle. Evaluate the vehicle that struck the patient for structural damage that might indicate contact points with the patient. and alert you to potential injuries. Multi-system injuries are common after this type of event. If available, consider summoning advanced life support backup for any patients who have or are thought to have sustained a significant mechanism of injury. Car vs. Bicycle In a car vs. bicycle crash, evaluate the mechanism of injury in much the same manner as car vs. pedestrian crashes. However, Additional evaluation of damage to end the position of the bicycle is warranted. If the patient was wearing a helmet, inspect the helmet for damage, and suspect potential injury to the head. Presume that the patient has sustained an injury to the spinal column, or spinal cord, until proven otherwise at the hospital. Initiate and maintain appropriate spinal motion restriction during the encounter. When practical. Roll the patient onto his or her side to allow for an appropriate assessment of the posterior side of the body. Car vs. Motorcycle In a motorcycle crash, any structural protection afforded to the victim is not derived from a steel cage, as is the case in an automobile, but from protective devices worn by the rider, that is, helmet, leather, or abrasion-resistant clothing, and boots. Although helmets are designed to protect against impact forces to the head. They do not protect from cervical spinal injury. Patients who have experienced a motorcycle crash should undergo cervical spine assessment and have a cervical collar placed if indicated. Leather and synthetic gear worn over the body was initially designed to protect professional riders in competition, where falls tend to be controlled and result in long sliding mechanisms on hard surfaces rather than multiple collisions against road objects and other vehicles. Leather clothing will mostly protect against road abrasion but offers no protection against blunt trauma from secondary impacts. In a street crash, collisions usually occur against other larger vehicles or stationary objects. When assessing the scene of a motorcycle crash, look for deformity of the motorcycle, the site 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. These findings can be helpful in estimating the extent of trauma sustained by a patient. There are four types of motorcycle impacts. Head-on crash. The motorcycle strikes another object and stops its forward motion while the rider and parts of the motorcycle that are broken off continue their forward motion until stopped by an outside force, such as drag from the road or another opposing force from a secondary collision. Angular crash. 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. This usually results in severe open and comminuted lower extremity injuries with severe neurovascular compromise, often resulting in traumatic amputation or otherwise requiring surgical amputation. Ejection The rider will travel at high speed until stopped by a stationary object, another vehicle, or road drag. Severe abrasion injuries, road rash, down to bone can occur with drag. An unpredictable combination of blunt injuries can occur from secondary collisions. Controlled crash. A technique used to separate the rider from the body of the motorcycle, and the object to be hit is referred to as laying the bike down. It was developed by motorcycle racers, and adapted by street bikers as a means of achieving a controlled crash. As a crash approaches, The motorcycle is turned flat and tipped sideways at 90 degrees to the direction of travel so that one leg is dropped to the grass or asphalt. This slows the occupant faster than the motorcycle, allowing the rider to become separated from the motorcycle. If properly protected with leather or synthetic abrasion-resistant gear, injuries should be limited to those sustained by rolling over the pavement, and any secondary collision that may occur. When executed properly. This maneuver prevents the rider from being trapped between the bike and the object. However, a rider unable to clear the bike will continue into the vehicle, often with devastating results. Falls The injury potential of a fall is related to the height from which the patient fell. Falls are common mechanism of injuries for blunt trauma. The greater the height of the fall, the greater the potential for injury. A fall for more than 20 feet, 6 meters, is considered significant. The patient lands on the surface just as an unrestrained passenger smashes into the interior of a vehicle. The internal organs travel at the speed of the patient's body before it hits the ground, and stop by smashing into the interior of the body. Again, as in a motor vehicle crash. It is these internal injuries that are the least obvious during assessment but pose the gravest threat to life. Therefore, suspect internal injuries in a patient who has fallen from a significant height, just as you would in a patient who has been in a high-speed motor vehicle crash. Always consider syncope or other underlying medical causes of the fall. Patients who fall and land on their feet may have less severe internal injuries because their legs may have absorbed much of the energy of the fall. However, As a result, they may have serious injuries to the lower extremities, and pelvic and spinal injuries from energy that was transmitted through the legs. Patients who impact head first, as in diving accidents, will likely have serious head and or spinal injuries. In either case, a fall from a significant height is a serious event with great injury potential, and the patient should be evaluated thoroughly. Take the following factors into account. The height of the fall. The type of surface struck, the part of the body that hit first, followed by the path of energy displacement. Many falls, especially those sustained by older patients, are not the result of high energy trauma, even though broken bones may result. Older patients often have osteoporosis, a condition in which the bones can fail under relatively low stress because they are structurally weakened. Because of this condition, An older patient can sustain a fracture as a result of a fall from a standing position. These cases do not constitute true high-energy trauma unless the patient fell from a significant height. Penetrating trauma Penetrating trauma is the second leading cause of trauma death in the United States after blunt trauma. In 2017, the Centers for Disease Control reported over 38,000 deaths from firearms, which is just under the number of deaths related to motor vehicles. Low-energy penetrating trauma may be caused accidentally by impalement or intentionally by a knife, ice pick, or other weapon. Often, it is difficult to determine the entrance and exit wounds from a projectile in a pre-hospital setting. First, determine the number of penetrating injuries, and then combine that information with the important things you already know about the potential pathway of penetrating projectiles to form an index of suspicion about unseen life-threatening injuries. With low energy penetrations, injuries are caused by the sharp edges of the object moving through the body, and are, therefore, close to the object's path. However, weapons such as knives may have been deliberately moved around internally, causing more damage than the external wound might suggest. Try to determine the length of the penetrating object. In medium and high velocity, speed, penetrating trauma, the path of the projectile, usually a bullet, may not be as long as the object. be as easy to predict. This is because the bullet may flatten out, tumble, or even ricochet within the body before exiting. The path the projectile takes is referred to as a trajectory. Fragmentation, especially frangible bullets that are designed to disintegrate into tiny particles on impact, will increase damage as multiple fragments increase the likelihood of multiple organs or vessels sustaining injury. Full Metal Jacket Bullet bullets cause less damage than fragmented rounds because of their tendency to pass through the body's tissues. The bullet speed is another factor in the resulting injury pattern. There is often additional damage caused by the object moving inside the body, but not along the suspected pathway. This phenomenon, called cavitation, results from the rapid changes in tissue and fluid pressure that occur with the passage of the projectile. and it can result in serious injury to internal organs distant to the actual path of the bullet. Consequences of cavitation can be temporary or permanent. Temporary cavitation injury results from a stretching of the tissues that occurs with the pressure changes. Permanent cavitation injury results along the path where the projectile, such as a bullet, has passed through the tissue. Remain alert. during assessment because patients will exhibit various signs and symptoms depending on the organ or organs affected. The relationship between distance and the severity of injury varies depending on the type of weapon involved, such as a rifle, pistol, or shotgun. Air resistance, often referred to as drag, slows the projectile, decreasing the depth of penetration and energy of the projectile and thus reducing damage to the tissues. Much like a boat moving through water, the bullet disrupts not only the tissues that are directly in its path but also those in its wake. Therefore, the area that is damaged by medium and high velocity projectiles is typically many times larger than the diameter of the projectile itself. This is one reason that exit wounds are often many times larger than entrance wounds. As with motor vehicle crashes, the energy available for a bullet to cause damage is more a function of its speed than its mass. Wait. If the mass of the bullet is doubled, the energy that is available to cause injury is doubled. If the velocity of the bullet is doubled, the energy that is available to cause injury is quadrupled. For this reason, it is important for you to try to determine the type of weapon that was used. Although it is not necessary, or always possible, for you to distinguish between medium, and high velocity injuries. Any information regarding the type of weapon that was used should be relayed to medical control. Medium-velocity injuries may be caused by handguns and some rifles, whereas high-velocity injuries may be caused by a military weapon. Police at the scene may be a useful source of information regarding the caliber of weapon. Most civilian gunshot wound injuries in the United States are the result of low-velocity weapons. An important factor for the seriousness of a gunshot wound is the type of tissue through which the projectile passes. Tissue of high elasticity, such as muscle, is better able to tolerate stretch than tissue of low elasticity, such as the liver. In a gunshot wound, shotgun wadding, bits of clothing, skin, and hair driven into the wound can cause massive contamination, leading to increased potential for infection should the patient survive the initial trauma. Table 25-1 summarizes how to recognize developing problems in trauma patients. Blast injuries. Although most commonly associated with military conflict, blast injuries are also seen in civilian practice in mines, shipyards, and chemical plants and, increasingly, in association with terrorist activities. As with any explosion, there is a risk of contamination of patients from environmental contaminants, toxic chemicals, or dirty bombs. People who are injured in explosions may be injured by any of four different mechanisms. Primary blast injuries. These injuries are due entirely to the blast itself, that is, damage to the body is caused by the pressure wave generated by the explosion. When the victim is close to the blast, the blast wave may cause disruption of major blood vessels and rupture of eardrums and major organs, including the lungs. Hollow organs are the most susceptible to the pressure wave. In some cases, pressure wave injuries can amputate limbs. Secondary blast injuries. Damage to the body results from being struck by flying debris, such as shrapnel from the device or from glass or splinters, which have been set in motion by the explosion. Objects are propelled by the force of the blast wave and strike the victim, causing injury. These objects can travel great distances, and be propelled at tremendous speeds. to almost 3,000 miles per hour for conventional military explosives. Tertiary blast injuries. These injuries occur when the patient is hurled by the force of the explosion against a stationary object. A blast wind, sudden change in the surrounding atmosphere, creates a pressure wave. This can cause the patient's body to be hurled or thrown, resulting in further injury. This physical displacement of the body is also referred to as ground shock when the body impacts. the ground. Quaternary blast injuries. This category of miscellaneous injuries includes burns from hot gases or fires started by the blast, respiratory injury from inhaling toxic gases, suffocation, poisoning, medical emergencies incurred as a result of the explosion, crush injuries from the collapse of buildings, contamination of wounds from environmental, chemical, or toxic substances, radiation injury from dirty bombs, and mental health emergencies. Essentially, all injuries due to the blast event that are not attributable directly to a primary, secondary, or tertiary mechanism are categorized as quaternary blast injuries. Most patients who survive an explosion will have some combination of the four types of injuries mentioned. The remainder of the discussion will be confined to primary blast injuries because while secondary blast injuries account for most of the trauma, primary injuries are the ones that are most easily overlooked. Tissues at risk, hollow organs, those that contain air, such as the middle ear, lung, and gastrointestinal tract, are most susceptible to pressure changes. The junction between tissues of different densities and exposed areas such as head and neck tissues are also susceptible to injury. The ear is the organ system that is most sensitive to blast injuries. The tympanic membrane evolved to detect minor changes in pressure and will rupture at pressures of 5 to 7 pounds per square inch above atmospheric pressure. Thus, the tympanic membranes are a sensitive indicator that you can use to help determine the possible presence of other blast injuries. The patient may report ringing in the ears, pain in the ears, or some loss of hearing, and blood may be visible in the ear canal. Dislocation of structural components of the ear, such as the ossicles conforming the inner ear, may occur. Permanent hearing loss is possible. These findings can be used to assist in triaging patients as they indicate risk of pressure injuries to the lungs. Pulmonary blast injuries are defined as pulmonary trauma, consisting of contusions. and hemorrhages that results from short-range exposure to the detonation of explosives. When the explosion occurs in an open space, both lungs are usually injured. Primary blast injury is often characterized by a lack of external visible injuries, and thus can go unrecognized. The patient may report tightness or pain in the chest, and may cough up blood, and have tachypnea or other signs of respiratory distress, subcutaneous emphysema, crackling under the skin. can be palpated over the chest, indicating air in the thorax. Pneumothorax is a common injury, and may require emergency decompression, which is covered in Chapter 30, Chest Injuries, in the field for your patient to survive. Pulmonary edema may ensue rapidly. If there is any reason to suspect lung injury in a blast victim, even just the presence of a ruptured eardrum, administer oxygen to maintain oxygen saturation of 94% to 99%. Avoid giving oxygen under positive pressure, however, because that may simply increase the damage to the lung or increase the size of a pneumothorax. One of the most concerning pulmonary blast injuries is arterial air embolism, which occurs on alveolar disruption with subsequent air embolization into the pulmonary vasculature. Even small air bubbles can enter a coronary artery and cause myocardial injury. Air embolisms to the cerebrovascular system can produce disturbances in vision, changes in behavior, changes in state of consciousness, and a variety of other neurologic signs. Solid organs are relatively protected from shock wave injury but may be injured by secondary missiles or a hurled body. Hollow organs, however, may be injured by the same mechanisms that damage lung tissue, skin injuries, ranging from petechiae. or pinpoint red-purple hemorrhages that show up on the skin, to large hematomas may be found. Perforation or rupture of the bowel and colon is a risk. Underwater explosions can result in severe abdominal injuries. Neurologic injuries and head trauma are the most common causes of death from blast injuries related to terrorist incidents. Subarachnoid, beneath the arachnoid layer covering the brain, and subdural, beneath the outermost covering of the brain. Hematomas are often seen. Permanent or transient neurologic deficits may be secondary to concussion, intracerebral bleeding, or air embolism. Instant but transient unconsciousness, with or without retrograde amnesia, may be initiated not only by head trauma, but also by cardiovascular problems. Bradycardia and hypotension are common after an intense pressure wave from an explosion. Extremity injuries, including traumatic amputations. are common. Patients with traumatic amputation by post-blast wind are likely to sustain fatal injuries secondary to the blast. In present-day combat, improved body armor has increased the number of survivors of blast injuries from shrapnel wounds to the torso. The number of severe orthopedic and extremity injuries, however, has increased. In addition, whereas body armor may limit or prevent shrapnel from entering the body. It also catches more energy from the blast wave, possibly resulting in the victim being thrown backward, thus increasing the potential for spine and spinal cord injury. Although blast injuries have usually occurred in war zones, they often occur in industrial settings, and are, unfortunately, currently more common because of the increased use of explosives as a tool for urban terrorism and, in the United States, from methamphetamine laboratory explosions. Although civilian blast injuries in an industrial or mining setting used to be mostly characterized by blast injuries and burns, terrorist bombs often contain shrapnel. As an emergency medical technician, you and other emergency medical service and trauma services personnel should be fully educated and aware of what to expect in these scenarios. Multi-system trauma. Multi-system trauma is a term that describes a person who has been subjected to multiple traumatic injuries involving more than one body system, such as head, and spinal trauma, chest and abdominal trauma, or chest and multiple extremity trauma. You must recognize patients who fit into this classification, and provide rapid treatment and transportation, and alert medical control as to the nature of the patient's injuries so that the trauma center is prepared prior to your arrival. Multi-system trauma patients have a high level of morbidity and mortality. Therefore, they require teams of physicians to treat their injuries. Golden principles of pre-hospital trauma care. As with any emergency medical service call, your main priority in managing multi-system trauma is to ensure your safety, and the safety of your crew and patient. Next, you must determine the need for additional personnel or equipment, evaluate the mechanism of injury. and identify and appropriately manage life threats. Once these steps have been completed, you can focus on patient care. Hemorrhage control has the highest priority. Severe bleeding from partial or complete amputations or other large wounds must be stopped. A tourniquet should be applied when bleeding from an extremity cannot be controlled using direct pressure, as discussed in Chapter 26, Bleeding. Assessing and Managing the Airway and Breathing including ventilatory support and high flow oxygen, while maintaining appropriate spinal motion restriction is the second priority. Ensure that other shock therapy, such as keeping the patient warm, is completed. Initiate spinal motion restriction precautions as indicated. If the patient is entrapped, consider the use of rapid extrication techniques. In most patients with multi-system trauma, definitive care requires surgical intervention, therefore, Unseen time should be limited to 10 minutes or less, referred to as the platinum 10. During transport, obtain a signs and symptoms, allergies, medications, pertinent past medical history, last oral intake, events leading up to the illness or injury history, and complete a secondary assessment. Most care can be provided during transport. However, keep in mind that your patient has sustained multi-system trauma. and the order in which you usually provide treatment and care may need to be adjusted depending on the needs of the patient. For critically injured patients, consider advanced life support intercept and or air medical transportation. Regardless of the mode of transport, ensure that the patient is transported to an appropriate facility, and that the facility is notified as soon as possible. Specific standards of care regarding multi-system trauma are addressed in detail in the respective chapters. Patient Assessment. Identifying life-threatening illnesses and injuries as soon as possible has proven to improve patient outcomes. As an emergency medical technician, you must apply this knowledge as well as the appropriate assessment skills to assess, triage, manage, and transport patients with traumatic injuries to the most appropriate facility. The major components of patient assessment include the following. Scene Size Up. Primary Assessment. History taking, secondary assessment, reassessment. When you are caring for a patient who has experienced a significant mechanism of injury and the patient is considered to be in serious or critical condition, you should rapidly perform a physical examination. With a patient who has experienced a non-significant mechanism of injury, focus on the chief complaint while assessing the patient as a whole. The human body is divided into areas, or systems, based on body function, and its internal organs are subject to unseen injuries when force is applied to the body. For example, the brain may have bruising, the heart and lungs may have bruising or unseen bleeding, and the organs of the abdomen may have life-threatening bleeding. The following sections discuss the assessment of various body systems. Injuries to the head. The brain lies well protected within the skull. However, when the head is injured from trauma, disability and unseen injury to the brain may occur. The brain itself may tear or become bruised, causing bleeding. The blood vessels around the brain may also tear and produce bleeding. Bleeding or swelling inside the skull from brain injury is often life-threatening. Therefore, your assessment must include conducting frequent neurologic examinations. Neurologic assessments, coupled with the patient's level of consciousness, will often provide details on subtle changes in the patient's condition. Some patients will not have obvious signs or symptoms, such as changes in pupillary size and reactivity, of unseen brain injury until minutes or hours after the injury has occurred. Injuries to the neck and throat. The neck and throat contain many structures that are susceptible to injuries from trauma that could be serious or deadly to your patients. In this region of the human body, the trachea, or windpipe, may become torn or swell after an injury to the neck or deviate after an injury to the lungs. These types of injuries may result in an airway problem that could quickly become a serious life threat because they interfere with the patient's ability to breathe. Therefore, Your assessment must include frequent physical examination looking for decap-BTLS in the neck region. In addition, you should assess for jugular venous, vein, distension and tracheal deviation, late sign of injury. The neck also contains large blood vessels that supply the brain with oxygen-rich blood. When a neck injury occurs, swelling may prevent blood flow to the brain and cause injury to the central nervous system. Even though the brain may not have been directly affected by the initial force that caused the injury to the neck, if a penetrating injury to the neck results in an open wound, the patient may have significant bleeding or air may be drawn into the circulatory system. If air enters the veins, this may result in air embolism, which may lead to cardiac arrest if the air enters the heart. Occlusive dressings must be used to keep this from happening. A crushing injury to the upper part of the neck may cause the cartilages of the upper airway and larynx to fracture. This can lead to air leaking into the soft tissue of the neck. When air is trapped in subcutaneous tissue, subcutaneous emphysema, it produces a crackling sound or feeling when palpated, called subcutaneous crepitation. Either air in the circulation or an airway cartilage fracture may cause rapid death. Injuries to the chest. The chest contains the heart. the lungs, and the large blood vessels of the body. When injury occurs to this area of the body, many life-threatening injuries may occur. For example, blunt trauma to the chest can fracture ribs or the sternum. When ribs are broken, and the chest wall does not expand normally during breathing, this interferes with the body's ability to obtain sufficient amounts of oxygen for the cells. Bruising may occur to the heart and cause an irregular heartbeat. Depending on the severity of the trauma, the large vessels of the heart may be torn inside the chest, causing massive unseen bleeding that can quickly kill the trauma patient. In some chest injuries the lungs become bruised, thus interfering with normal oxygen exchange in the body. Some chest injuries result in air collecting between the lung tissue, and the chest wall. As air accumulates in this space, the lung tissue becomes compressed. again interfering with the body's ability to effectively exchange oxygen. This injury is called a pneumothorax. If left untreated or unrecognized, the lung tissue becomes squeezed under pressure until the heart is also squeezed and can no longer pump blood. This condition is called a tension pneumothorax, and is a life-threatening emergency. In some patients, bleeding develops in this portion of the chest, instead of air collecting in this space. Blood collects and causes interference with breathing. This condition is called a hemothorax, and it also poses a threat to the patient's life. A penetration or perforation of the integrity of the chest is called an open chest wound. As air enters the chest cavity, the natural pressure balance within the chest cavity is no longer equal. If left untreated, shock and or death will result, regardless of the particular injury. It is imperative that you reassess a trauma patient's chest region every five minutes. The assessment should include decap-BTLS, lung sounds, and chest rise and fall. Some patients will not have obvious signs or symptoms such as absent breath sounds or respiratory difficulty immediately. Injuries to the abdomen The abdomen is an area of the human body that contains many organs vital to body function. These organs also require a high blood pressure. flow so they can perform the functions necessary for life. The organs of the abdomen and retroperitoneum, the space immediately behind the true abdomen, can be classified into two simple categories, solid and hollow. The solid organs include the liver, spleen, pancreas, and kidneys. The hollow organs include the stomach, large and small intestines, and urinary bladder. When injuries from trauma occur in this region of the body, serious and life-threatening problems may occur the solid organs may tear lacerate or fracture this causes serious bleeding into the abdomen that can quickly cause death be alert for a trauma patient who reports abdominal pain it may be a symptom of abdominal bleeding also be alert to vital signs that begin to worsen this can be a sign of serious unseen bleeding inside the abdominal region of the body When the hollow organs of the body have been injured, they may rupture and leak toxic chemicals used for digestion into the abdomen. This not only causes pain, but a life-threatening infection also may eventually develop. The abdomen also contains large blood vessels that supply the organs of this region, and the lower extremities with oxygen-rich blood. Occasionally these vessels rupture or tear and cause serious unseen bleeding that may cause death. Some patients particularly healthy young adults, are able to compensate longer than others from blood loss. Therefore, you should always maintain a high index of suspicion when the mechanism of injury suggests injury to the abdominal region. This is best accomplished by reassessing the abdominal region. Management, transport and destination. Caring for victims of traumatic injuries requires a solid understanding of the trauma system in the United States. You need a good working knowledge of the resources available to you, including the most optimal methods of rapid transport and trauma centers that can best provide definitive care. Call for advanced life support and helicopter assistance early, possibly even before you arrive on scene, to avoid delays in treatment and transport. Scene time. Because survival of critically injured trauma patients is time dependent. Limit on-scene time to the minimum amount necessary to correct life-threatening injuries and package the patient. Optimally, on-scene time for critically injured patients should be less than 10 minutes, the platinum 10. The following criteria will help you identify a critically injured patient. Dangerous mechanism of injury. Decreased level of consciousness. Any threats to airway, breathing, or circulation. Patients who present with these criteria or who are very young or old or have chronic illnesses should also be considered to be high risk, thus requiring rapid treatment, and transport. Destination Selection You will often be summoned to injury scenes to transport critically ill trauma patients to definitive care. For this reason, it is important for you to be familiar with how the American College of Surgeons Committee on Trauma classifies trauma care. Trauma centers are classified into levels 1 through 4, with level 1 having the most resources, followed by levels 2, 3, and 4. A level 1 facility is a regional resource center, and generally serves large cities or heavily populated areas. Level 1 facilities must be capable of providing every aspect of trauma care from prevention through rehabilitation. Therefore, the facility must have adequate personnel and resources. Because of the extensive requirements, most Level 1 facilities are university-based teaching hospitals. A Level 2 facility is typically located in less populated areas. Level 2 centers are expected to provide initial definitive care, regardless of injury severity. These facilities can be academic institutions or a public or private community facility, because of its location and resources. A level 2 trauma center may not be able to provide the same comprehensive care as a level 1 trauma center. Level 3 facilities serve communities that do not have access to level 1 or 2 facilities. Level 3 facilities provide assessment, resuscitation, emergency care, and stabilization. A level 3 facility must have transfer agreements with a level 1 or 2 trauma center. and must have protocols in place to transfer patients whose needs exceed the resources of the facility. Level 4 facilities are typically found in remote outlying areas where no higher level of care is available. These facilities provide ADLS prior to transfer to a higher level trauma center. Such a facility may be a clinic urgent care facility, with or without a physician. Although an inclusive trauma system should leave no facility without a direct link to a level 1 or 2 facility, all facilities are expected to provide the same high quality of initial care regardless of the classification level. Trauma centers are categorized as either adult trauma centers or pediatric trauma centers, but not necessarily both. Pediatric trauma centers are not nearly as common as adult trauma centers. When transporting a pediatric trauma patient, You must be certain to transport your patient to a pediatric trauma center if there is one in your area. Do not make the mistake of transporting a pediatric patient to an adult trauma center when a pediatric trauma center is available. In 2011, the American College of Surgeons Committee on Trauma in the Centers for Disease Control published an updated field triage decision scheme. These criteria are intended to help pre-hospital care providers recognize injured patients who are likely to benefit from transport to a trauma center compared with transport to an emergency department. The decision scheme is not intended to serve as a mass casualty or disaster triage tool. It is intended only for individual patients. Type of transport. Modes of transport ultimately come in one of two categories, ground or air. Transport modes are discussed further in Chapter 15, Medical Overview. Ground Transportation Emergency Medical Service Units are generally staffed by emergency medical technicians and paramedics. Air Transportation Emergency Medical Service Units or Critical Care Transport Units are often staffed by critical care transport professionals such as critical care nurses and paramedics. You should be familiar with your local protocols defining indications for use of helicopter emergency medical services transport. In 2014, an expert panel developed evidence-based guidelines for the appropriate use of emergency air medical services for trauma patients. Field triage criteria for trauma patients should include anatomic, physiologic, and situational components based on the Centers for Disease Control's 2011 Guidelines for the Field Triage of Injured Patients. These guidelines help predict injury severity to determine the need for helicopter or ground ambulance transport. When it is not clear that the patient meets the guidelines for severity, medical direction should be consulted to determine the appropriate means of transport for the patient. Factors to consider when determining whether the patient is seriously injured include the following. There is an extended period required to access or extricate a remote, for example, injured hiker, snowmobiler, or boater, or trapped patient, for example, in a crashed car, who has evidence of serious injury, and this access or extrication depletes the time window to get the patient to the trauma center by ground. The patient needs medical care and stabilization at the advanced life support level, and there is no advanced life support level ground ambulance service available within a reasonable time frame. Traffic conditions or hospital availability make it unlikely that the seriously injured patient will get to a trauma center via ground ambulance within the ideal time frame for best clinical outcome. There is a mass casualty incident with serious injuries. These recommendations are not to be understood as fully encompassing, but more as a guideline for local decision makers to develop more comprehensive protocols for the use of helicopter emergency medical services transport. Always follow your local protocols when determining what type of patient transportation is appropriate. Special considerations. Because traumatic injuries are as varied as the mechanisms that cause them. It is almost impossible to prepare for every possible situation that you may face during your career. In all situations, you must remain calm, complete an organized assessment, correct life-threatening injuries, and do no harm. You should never hesitate to contact Advanced Life Support Backup or Medical Control for guidance.

This is discussed further in Chapter 15, Medical Overview. Trauma emergencies occur as a result of physical forces applied to the body. Medical emergencies include illnesses or conditions. These are not caused by an outside force.

Traumatic injuries may be caused by underlying medical conditions. A patient has a stroke and veers off the road, striking a tree. Similarly, medical illnesses may result from recent or remote traumatic injuries.

Pneumonia develops in a patient a few days after a fall that fractured the patient's ribs. This chapter introduces the basic physical concepts that dictate how traumatic injuries occur and how they affect the human body. When you understand these concepts, you'll be better prepared to size up a vehicular crash scene and assess a patient.

This chapter begins with the basic discussion of energy and trauma. Next, different types of vehicle crashes, and their effect on the body are explained. By assessing a vehicle that has crashed, you can often determine what happened to the passengers at the time of impact.

This may allow you to predict what injuries the passengers sustained at the time of impact. Evaluation of the mechanism of injury for the trauma patient will provide you with an index of suspicion for different types of serious and or life-threatening underlying injuries. Certain injury patterns occur with certain types of injury events.

The index of suspicion is your awareness and concern for potentially serious underlying and unseen injuries. Energy and Trauma Traumatic injury occurs when the body's tissues are exposed to energy levels beyond their tolerance. The mechanism of injury is the way in which traumatic injuries occur. It describes the forces, or energy transmission, acting on the body that cause injury.

Three concepts of energy are typically associated with injury, not including thermal energy, which causes burns, potential energy, kinetic energy, and the energy of work. When considering the effects of energy on the human body, it is important to remember that energy can be neither created nor destroyed. It can only be converted or transformed.

It is not the objective of this section to help you reconstruct the scene of a motor vehicle crash. Rather, you should have a sense of the effects of the event on the human body, and understand, in a broad sense, how that event is related to potential and kinetic energy. For example, when assessing a patient who fell, you need not calculate the speed at which the person hit the ground. Instead, focus on the factors of the impact. and how those relate to the potential for injury.

For example, it is important to estimate the height from which the patient fell, as well as the surface he or she landed on, to fully appreciate the injury potential of the fall. Work is defined as force acting over a distance. For example, the force needed to bend metal multiplied by the distance over which the metal is bent is the work that crushes the front end of a vehicle that is involved in a frontal impact.

Similarly, forces that bend pull or compressed tissues beyond their inherent limits result in the work that causes injury the energy of a moving object is called kinetic energy kinetic energy reflects the relationship between the mass weight of the object and the velocity speed at which it is traveling kinetic energy is expressed as kinetic energy equals one-half mass times velocity squared or kinetic energy equals one-half of a meter times V squared remember Energy cannot be created or destroyed, only converted. In the case of a motor vehicle crash, the kinetic energy of the speeding vehicle is converted into the work of stopping the vehicle, usually by crushing the vehicle's exterior. Similarly, the passengers of the vehicle have kinetic energy because they were traveling at the same speed as the vehicle.

Their kinetic energy is converted to the work of bringing them to a stop. It is this work on the passengers that results in injury. Notice that, according to the equation for kinetic energy, the energy that is available to cause injury doubles when an object's weight doubles but quadruples when its speed doubles. When a car's speed increases from 50 to 70 miles per hour, the energy that is available to cause injury nearly doubles. This point is even clearer when considering gunshot wounds.

The speed of the bullet, high velocity compared with low velocity, has a greater impact on producing injury than the mass, size, of the bullet. Therefore, it is important to report to the hospital the type of firearm that was used in a shooting. The amount of kinetic energy that is converted to do work on the body dictates the severity of the injury.

High energy injuries often produce such severe damage that patients require immediate transport to an appropriate facility to have any hope of survival. Potential energy is the product of mass, weight, force of gravity, and height and is mostly associated with the energy of falling objects. A worker on a scaffold has potential energy because he or she is some height above the ground.

If the worker falls, potential energy is converted into kinetic energy. As the worker hits the ground, The kinetic energy is converted into work, that is, the work of bringing the body to a stop, and thereby fracturing bones and damaging tissues. Mechanism of Injury Profiles Different types of mechanism of injuries will produce many types of injuries. Examples of non-significant injuries include injury to an isolated body part or a fall without the loss of consciousness. Examples of significant mechanism of injuries include injury to more than one body system.

Multi-system trauma, falls from heights, motor vehicle and motorcycle crashes, car versus pedestrian, or bicycle or motorcycle, gunshot wounds, and stabbings. Whether one or more body systems are involved, maintain a high index of suspicion for serious unseen injuries. Blunt and penetrating trauma. Traumatic injuries can be considered in two categories, blunt trauma and penetrating trauma.

Blunt trauma is the result of force. or energy transmission, to the body that causes injury without anything penetrating the soft tissues or internal organs and cavities. Penetrating trauma results in injury by objects that pierce and penetrate the surface of the body, and injure the underlying soft tissues, internal organs, and body cavities.

Either type of trauma may occur from a variety of mechanism of injuries. It is important to consider unseen as well as visible, obvious injuries with either type of trauma. Damage to the underlying deeper tissues is often more significant. Blunt trauma. Blunt trauma results from an object making contact with the body.

Any object, such as a baseball bat, can cause blunt trauma if it is moving fast enough. Motor vehicle crashes and falls are two of the most common mechanism of injuries for blunt trauma. When providing care for your patient, be alert to signs of skin discoloration or reports of pain because these may be the only signs of blunt trauma.

During assessment, maintain a high index of suspicion for hidden injuries in patients with blunt trauma. Vehicular crashes Motor vehicle crashes are traditionally classified as frontal, head-on, rear-end, lateral, T-bone, rollover, and rotational . The principal difference among these crash types is the direction of the force of impact.

Also, with spins and rollovers, There is the possibility of multiple impacts. Motor vehicle crashes typically consist of a series of three collisions. Understanding the events that occur during each one of these three collisions will help you be alert for certain types of injury patterns. The three collisions in a typical impact are as follows.

1. The collision of the car against another car, a tree, or some other object. Damage to the car is perhaps the most dramatic part of the collision. but it does not directly affect patient care, except possibly to make extrication difficult.

However, it does provide information about the severity of the collision, and therefore has an indirect effect on patient care. The greater the damage to the car, the greater the energy that was involved and, therefore, the greater the potential to cause injury to the patient. By assessing the vehicle that has crashed, you can often determine the mechanism of injury.

which may allow you to predict what injuries may have happened to the passengers at the time of impact according to forces that acted on their bodies. When you arrive at the crash scene, and perform your scene size up, quickly inspect the severity of damage to the vehicle or vehicles. If there is significant damage to a vehicle, your index of suspicion for the presence of life-threatening injuries should automatically increase. A great amount of force is required to crush, and deform a vehicle.

cause intrusion into the passenger compartment, tear seats from their mountings, and collapse steering wheels. Such damage suggests the presence of high-energy trauma. 2. The collision of the passenger against the interior of the car. Just as the kinetic energy produced by the vehicle's mass and velocity is converted into the work of bringing the vehicle to a stop, the kinetic energy produced by the passenger's mass and velocity is converted into the work of stopping his or her body. Just like the obvious damage to the exterior of the car, the injuries that result are often dramatic and usually immediately apparent during your scene size-up or primary assessment.

Common passenger injuries include lower extremity fractures, knees into the dashboard, rib fractures, rib cage into the steering wheel, and head trauma, head into the windshield. Such injuries occur more frequently if the passenger is not restrained. But even when the passenger is restrained with a properly adjusted seat belt, injuries can occur, especially in lateral and rollover impacts.

3. The collision of the passenger's internal organs against the solid structures of the body. The injuries that occur during the third collision may not be the only ones. be as obvious as external injuries, but they are often the most life-threatening. For example, as the passenger's head hits the windshield, the brain continues to move forward until it comes to rest by striking the inside of the skull.

This results in a compression injury to the anterior portion of the brain, and a tension injury of the posterior portion of the brain. This is an example of a coup-contre-coup brain injury. Traumatic aortic transaction or rupture is associated with a sudden and rapid deceleration of the heart and the aorta within the thoracic cavity, which may rupture the aorta and cause fatal bleeding.

Understanding the relationships among the three collisions will help you make the connections between the amount of damage to the exterior of the vehicle and potential injury to the passenger. For example, in a high-speed crash that results in massive damage to the vehicle, you should suspect serious injuries to the passengers. Even if the injuries are not readily apparent, several potential physical problems may develop as a result of traumatic injuries. Your initial general impression of the patient and evaluation of the mechanism of injury can help direct life-saving care and provide critical information to the hospital staff.

Therefore, if you see a contusion on the patient's forehead and the windshield is starred and pushed out, you should strongly suspect an injury to the brain. After you inform medical control about the damage to the windshield, hospital staff can prepare for the patient by being ready to perform a computed tomography scan of the brain. Without your input, the physician might have found the brain injury anyway, but it might not have been detected until the brain had swollen sufficiently to cause clinical signs of the injury.

Whenever there is a significant impact to the head, also suspect a spinal injury, and take cervical spine precautions if indicated. The amount of damage considered significant varies, depending on the type of crash, but any substantial deformity of the vehicle should be enough cause for you to consider transporting the patient to a trauma center. Significant mechanism of injuries are suggested by the following findings.

Death of an occupant in the vehicle. Severe deformity of the vehicle or intrusion into the vehicle. Severe deformities of the frontal part of the vehicle, with or without intrusion into the passenger compartment. Moderate intrusions from a lateral, T-bone, type of accident. Severe damage from the rear.

Crashes in which rotation is involved. Rollovers and spins. Ejection from the vehicle. Damage to the vehicle that was involved. And information obtained during the scene size-up are not the only clues you can use to determine crash severity.

Clearly, if one or more of the passengers are dead, you should suspect that the other passengers have sustained serious injuries. even if the injuries are not obvious. Therefore, focus on treating life-threatening injuries and providing rapid transport to a trauma center, because these passengers have likely experienced the same amount of force that caused the death of the others.

Digital photos of the crash scene may provide valuable information to the staff and treating physicians at the trauma center. However, photos should be shown or transmitted only to appropriate personnel and should never be shared over social media. Photos containing patient images or other identifiable patient information may become part of the medical record or may need to be deleted after review by the receiving health care providers, depending on protected health information policies developed by the department privacy officer.

Frontal crashes. Understanding the mechanism of injury after a frontal crash first involves evaluation of the supplemental restraint system, including seatbelts and airbags. Determine whether the passenger was restrained by a full and properly applied three-point restraint.

Also determine whether the airbag was deployed. Identifying the types of restraints used and whether airbags were deployed will help you identify injury patterns related to the supplemental restraint systems. When properly applied, seatbelts are successful in restraining the passengers in a vehicle and preventing a second collision inside the motor vehicle. According to the Centers for Disease Control and Prevention, seatbelt use saved an estimated 15,000 lives in 2016. Seat belts may also decrease the severity of the third collision, that of the passenger's organs with the chest or abdominal wall. The protective abilities of seat belts are further enhanced by deployment of the airbags.

Airbags provide the final capture point of the passengers, and decrease the severity of deceleration injuries by allowing seat belts to be more compliant and by gently cushioning the occupant as the body slows, or decelerates. Remember that airbags decrease injury to the chest, face, and lower back. and head very effectively. However, you should still suspect that other serious injuries to the extremities, resulting from the second collision, and to internal organs, resulting from the third collision, have occurred. Airbags have been standard equipment in most motor vehicles since 1999. These safety devices enhance the safety and survival of forward-facing occupants inside the vehicle during a crash, in an emergency braking event, or crash.

the airbag inflates very quickly because a rear-facing car seat is in proximity to the dashboard rapid inflation of the airbag could cause serious injury or death to an infant all children who are shorter than four feet nine inches 145 centimeters should ride in the rear seat or in the case of a pickup truck or other single-seated vehicle the airbag should be turned off when providing care to an occupant inside a motor vehicle It is important to remember that if the airbag did not inflate during the accident, it may deploy during extrication. If this occurs, you may be seriously injured. Extreme caution must be used when extricating a patient in a vehicle with an airbag that has not deployed.

Supplemental restraint systems can also cause harm depending on whether they are used properly or improperly. For example, some older vehicle models have seat belts that buckle automatically at the shoulder but require the passengers to buckle the lap portion. Not buckling the lap portion can cause the occupant to travel down and under the shoulder strap as the body continues forward, resulting in the lower body striking the dashboard. This movement of the body can cause the lower extremities and the pelvis to crash into the dashboard because that part of the body is unrestrained. Feet belts may also cause unseen abdominal injuries, particularly in pediatric patients.

Seatbelts are designed to be worn over the iliac crests of the pelvis to distribute the force over the bony surface. Hip dislocations may result if seatbelts are worn too low. Internal injuries can occur when the belt is worn too high, resulting in damage to abdominal organs. Lumbar spine fractures are also possible, particularly in children and older patients.

When passengers are riding in vehicles equipped with airbags but are not restrained by seatbelts, They are often thrown forward in the act of emergency braking. As a result, they come into contact with the airbag and or the doors at the time of deployment. This mechanism of injury is also responsible for some severe injuries to children who are riding unrestrained in the front seats of vehicles, unrestrained passengers, and those sitting too close to the airbag.

Today's motor vehicles often have multiple airbags and side curtains. These are designed to protect the occupants of the vehicle. but can also alter injury patterns.

Certain areas of a vehicle's body may have airbags that will deploy when impacted. Pushing on or using extrication tools in those areas may cause airbags to unexpectedly deploy. This can happen even after the car battery has been disengaged.

In addition, some passengers may pass out before impact, and you may find them lying against the deployed airbag. When you encounter these types of situations, Look for abrasions and or traction type injuries on the face, lower part of the neck, and chest. Contact points are often obvious as you perform a simple, quick evaluation of the interior of the vehicle.

If there is no intrusion into the passenger compartment, you might see that an unrestrained front seat passenger in a frontal crash has come into contact with the dashboard or the instrument panel at the knees, thus transferring loads from the knees through the femur to the pelvis and hip joint. The chest and or abdomen may also hit the steering wheel. In addition, the passenger's face often hits the steering wheel, or the passenger may launch forward and up, hitting the windshield and or the roof header in the area of the visors. Signs of most of these injuries can be found by inspecting the interior of the vehicle during extrication of the patient. Rear-end crashes.

Rear-end impacts are known to cause whiplash injuries, particularly when the passenger's head and or neck is not restrained by an appropriately placed headrest. On impact, the passenger's body and torso move forward. As the body is propelled forward, the head and neck are left behind because the head is relatively heavy.

and they appear to be whipped back relative to the torso. As the vehicle comes to rest, the unrestrained passenger moves forward, striking the dashboard. In this type of crash, the cervical spine, and surrounding area may be injured. The cervical spine is less tolerant of damage when it is bent back.

Headrests decrease extension of the head and neck during a crash and, therefore, help reduce injury. Other parts of the spine and the pelvis may also be at risk for injury. In addition, the patient may sustain an acceleration injury to the brain, that is, the third collision of the brain within the skull.

Passengers in the backseat wearing only a lap belt might have a higher incidence of injuries to the thoracic and lumbar spine. Lateral crashes. Lateral or side impacts, commonly called T-bone crashes, are a common cause of death associated with motor vehicle crashes.

When a vehicle is struck from the side, it is typically struck above its center of gravity, and begins to rock away from the side of the impact. This results in the passenger sustaining a lateral whiplash injury. The movement is to the side, and the passenger's shoulders and head whip toward the intruding vehicle. This action may thrust the shoulder, thorax, and upper extremities, and, more important, the skull against the doorpost or the window. The cervical spine has little tolerance for lateral bending.

If there is substantial intrusion into the passenger compartment, suspect your patient to have lateral chest and abdomen injuries on the side of the impact, as well as possible fractures of the lower extremities, pelvis, and ribs. In addition, the organs within the abdomen are at risk because of a possible third collision, according to the Journal of Safety Research. Lateral crashes cause approximately 25% of all severe injuries to the aorta, and approximately 30% of all fatalities that occur in motor vehicle crashes. Rollover crashes.

Certain vehicles, such as large trucks, and some sport utility vehicles, are more susceptible to rollover crashes because of their high center of gravity. Injury patterns that are commonly associated with rollover crashes differ, depending on whether the passenger was restrained or unrestrained. The most unpredictable types of injuries are caused by rollover crashes in which an unrestrained passenger may have sustained multiple strikes within the interior of the vehicle as it rolled one or more times.

The most common life-threatening event in a rollover is ejection or a partial ejection of the passenger from the vehicle. Passengers who have been ejected may have struck the interior of the vehicle many times before ejection. The passenger may also have struck several objects, such as trees, a guardrail.

or the vehicle's exterior, before landing. Passengers who have been partially ejected may have struck both the interior and exterior of the vehicle, and may have been sandwiched between the exterior of the vehicle, and the environment as the vehicle rolled. Ejection and partial ejection are significant mechanism of injuries.

In these cases, prepare to care for life-threatening injuries. Even when restrained, passengers can sustain severe injuries during a rollover crash. Although the patterns of injury tend to be more predictable, and when the restraint system is properly used, ejection from the vehicle is less likely.

A passenger on the outboard side of a vehicle that rolls over is at high risk for injury because of the centrifugal force. The patient is pinned against the door of the vehicle. Rollover crashes can also cause injury when the roof of the vehicle hits the ground during the rollover. A passenger who is restrained can still move far enough toward the roof to make contact and sustain a spinal cord injury. Therefore, rollover crashes are dangerous for both restraint and, to a greater degree, unrestrained passengers because these crashes provide multiple opportunities for second and third collisions.

Rotational crashes Rotational crashes, spans, are conceptually similar to rollovers. The rotation of the vehicle as it spins provides opportunities for the vehicle to strike objects such as utility poles. For example, as a vehicle spins and strikes a pole, the passengers experience not only the rotational motion, but also a lateral impact.

Car vs. Pedestrian Car vs. Pedestrian crashes often result in patients who have graphic and apparent injuries, such as broken bones, however. This type of crash can cause serious unseen injuries to underlying body systems. Therefore, you must maintain a high index of suspicion for unseen injuries.

A thorough evaluation of the mechanism of injury is critical. First, estimate the speed of the vehicle that struck the patient. Next, determine whether the patient was thrown, what surface the patient landed on, and at what distance or whether the patient was struck and pulled under the vehicle. Evaluate the vehicle that struck the patient for structural damage that might indicate contact points with the patient.

and alert you to potential injuries. Multi-system injuries are common after this type of event. If available, consider summoning advanced life support backup for any patients who have or are thought to have sustained a significant mechanism of injury.

Car vs. Bicycle In a car vs. bicycle crash, evaluate the mechanism of injury in much the same manner as car vs. pedestrian crashes. However, Additional evaluation of damage to end the position of the bicycle is warranted. If the patient was wearing a helmet, inspect the helmet for damage, and suspect potential injury to the head.

Presume that the patient has sustained an injury to the spinal column, or spinal cord, until proven otherwise at the hospital. Initiate and maintain appropriate spinal motion restriction during the encounter. When practical.

Roll the patient onto his or her side to allow for an appropriate assessment of the posterior side of the body. Car vs. Motorcycle In a motorcycle crash, any structural protection afforded to the victim is not derived from a steel cage, as is the case in an automobile, but from protective devices worn by the rider, that is, helmet, leather, or abrasion-resistant clothing, and boots. Although helmets are designed to protect against impact forces to the head.

They do not protect from cervical spinal injury. Patients who have experienced a motorcycle crash should undergo cervical spine assessment and have a cervical collar placed if indicated. Leather and synthetic gear worn over the body was initially designed to protect professional riders in competition, where falls tend to be controlled and result in long sliding mechanisms on hard surfaces rather than multiple collisions against road objects and other vehicles. Leather clothing will mostly protect against road abrasion but offers no protection against blunt trauma from secondary impacts.

In a street crash, collisions usually occur against other larger vehicles or stationary objects. When assessing the scene of a motorcycle crash, look for deformity of the motorcycle, the site 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. These findings can be helpful in estimating the extent of trauma sustained by a patient.

There are four types of motorcycle impacts. Head-on crash. The motorcycle strikes another object and stops its forward motion while the rider and parts of the motorcycle that are broken off continue their forward motion until stopped by an outside force, such as drag from the road or another opposing force from a secondary collision.

Angular crash. 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. This usually results in severe open and comminuted lower extremity injuries with severe neurovascular compromise, often resulting in traumatic amputation or otherwise requiring surgical amputation.

Ejection The rider will travel at high speed until stopped by a stationary object, another vehicle, or road drag. Severe abrasion injuries, road rash, down to bone can occur with drag. An unpredictable combination of blunt injuries can occur from secondary collisions. Controlled crash. A technique used to separate the rider from the body of the motorcycle, and the object to be hit is referred to as laying the bike down.

It was developed by motorcycle racers, and adapted by street bikers as a means of achieving a controlled crash. As a crash approaches, The motorcycle is turned flat and tipped sideways at 90 degrees to the direction of travel so that one leg is dropped to the grass or asphalt. This slows the occupant faster than the motorcycle, allowing the rider to become separated from the motorcycle. If properly protected with leather or synthetic abrasion-resistant gear, injuries should be limited to those sustained by rolling over the pavement, and any secondary collision that may occur.

When executed properly. This maneuver prevents the rider from being trapped between the bike and the object. However, a rider unable to clear the bike will continue into the vehicle, often with devastating results.

Falls The injury potential of a fall is related to the height from which the patient fell. Falls are common mechanism of injuries for blunt trauma. The greater the height of the fall, the greater the potential for injury.

A fall for more than 20 feet, 6 meters, is considered significant. The patient lands on the surface just as an unrestrained passenger smashes into the interior of a vehicle. The internal organs travel at the speed of the patient's body before it hits the ground, and stop by smashing into the interior of the body. Again, as in a motor vehicle crash. It is these internal injuries that are the least obvious during assessment but pose the gravest threat to life.

Therefore, suspect internal injuries in a patient who has fallen from a significant height, just as you would in a patient who has been in a high-speed motor vehicle crash. Always consider syncope or other underlying medical causes of the fall. Patients who fall and land on their feet may have less severe internal injuries because their legs may have absorbed much of the energy of the fall.

However, As a result, they may have serious injuries to the lower extremities, and pelvic and spinal injuries from energy that was transmitted through the legs. Patients who impact head first, as in diving accidents, will likely have serious head and or spinal injuries. In either case, a fall from a significant height is a serious event with great injury potential, and the patient should be evaluated thoroughly.

Take the following factors into account. The height of the fall. The type of surface struck, the part of the body that hit first, followed by the path of energy displacement. Many falls, especially those sustained by older patients, are not the result of high energy trauma, even though broken bones may result. Older patients often have osteoporosis, a condition in which the bones can fail under relatively low stress because they are structurally weakened.

Because of this condition, An older patient can sustain a fracture as a result of a fall from a standing position. These cases do not constitute true high-energy trauma unless the patient fell from a significant height. Penetrating trauma Penetrating trauma is the second leading cause of trauma death in the United States after blunt trauma.

In 2017, the Centers for Disease Control reported over 38,000 deaths from firearms, which is just under the number of deaths related to motor vehicles. Low-energy penetrating trauma may be caused accidentally by impalement or intentionally by a knife, ice pick, or other weapon. Often, it is difficult to determine the entrance and exit wounds from a projectile in a pre-hospital setting. First, determine the number of penetrating injuries, and then combine that information with the important things you already know about the potential pathway of penetrating projectiles to form an index of suspicion about unseen life-threatening injuries.

With low energy penetrations, injuries are caused by the sharp edges of the object moving through the body, and are, therefore, close to the object's path. However, weapons such as knives may have been deliberately moved around internally, causing more damage than the external wound might suggest. Try to determine the length of the penetrating object. In medium and high velocity, speed, penetrating trauma, the path of the projectile, usually a bullet, may not be as long as the object. be as easy to predict.

This is because the bullet may flatten out, tumble, or even ricochet within the body before exiting. The path the projectile takes is referred to as a trajectory. Fragmentation, especially frangible bullets that are designed to disintegrate into tiny particles on impact, will increase damage as multiple fragments increase the likelihood of multiple organs or vessels sustaining injury.

Full Metal Jacket Bullet bullets cause less damage than fragmented rounds because of their tendency to pass through the body's tissues. The bullet speed is another factor in the resulting injury pattern. There is often additional damage caused by the object moving inside the body, but not along the suspected pathway.

This phenomenon, called cavitation, results from the rapid changes in tissue and fluid pressure that occur with the passage of the projectile. and it can result in serious injury to internal organs distant to the actual path of the bullet. Consequences of cavitation can be temporary or permanent.

Temporary cavitation injury results from a stretching of the tissues that occurs with the pressure changes. Permanent cavitation injury results along the path where the projectile, such as a bullet, has passed through the tissue. Remain alert. during assessment because patients will exhibit various signs and symptoms depending on the organ or organs affected.

The relationship between distance and the severity of injury varies depending on the type of weapon involved, such as a rifle, pistol, or shotgun. Air resistance, often referred to as drag, slows the projectile, decreasing the depth of penetration and energy of the projectile and thus reducing damage to the tissues. Much like a boat moving through water, the bullet disrupts not only the tissues that are directly in its path but also those in its wake.

Therefore, the area that is damaged by medium and high velocity projectiles is typically many times larger than the diameter of the projectile itself. This is one reason that exit wounds are often many times larger than entrance wounds. As with motor vehicle crashes, the energy available for a bullet to cause damage is more a function of its speed than its mass. Wait. If the mass of the bullet is doubled, the energy that is available to cause injury is doubled.

If the velocity of the bullet is doubled, the energy that is available to cause injury is quadrupled. For this reason, it is important for you to try to determine the type of weapon that was used. Although it is not necessary, or always possible, for you to distinguish between medium, and high velocity injuries. Any information regarding the type of weapon that was used should be relayed to medical control.

Medium-velocity injuries may be caused by handguns and some rifles, whereas high-velocity injuries may be caused by a military weapon. Police at the scene may be a useful source of information regarding the caliber of weapon. Most civilian gunshot wound injuries in the United States are the result of low-velocity weapons.

An important factor for the seriousness of a gunshot wound is the type of tissue through which the projectile passes. Tissue of high elasticity, such as muscle, is better able to tolerate stretch than tissue of low elasticity, such as the liver. In a gunshot wound, shotgun wadding, bits of clothing, skin, and hair driven into the wound can cause massive contamination, leading to increased potential for infection should the patient survive the initial trauma.

Table 25-1 summarizes how to recognize developing problems in trauma patients. Blast injuries. Although most commonly associated with military conflict, blast injuries are also seen in civilian practice in mines, shipyards, and chemical plants and, increasingly, in association with terrorist activities. As with any explosion, there is a risk of contamination of patients from environmental contaminants, toxic chemicals, or dirty bombs.

People who are injured in explosions may be injured by any of four different mechanisms. Primary blast injuries. These injuries are due entirely to the blast itself, that is, damage to the body is caused by the pressure wave generated by the explosion. When the victim is close to the blast, the blast wave may cause disruption of major blood vessels and rupture of eardrums and major organs, including the lungs.

Hollow organs are the most susceptible to the pressure wave. In some cases, pressure wave injuries can amputate limbs. Secondary blast injuries. Damage to the body results from being struck by flying debris, such as shrapnel from the device or from glass or splinters, which have been set in motion by the explosion.

Objects are propelled by the force of the blast wave and strike the victim, causing injury. These objects can travel great distances, and be propelled at tremendous speeds. to almost 3,000 miles per hour for conventional military explosives.

Tertiary blast injuries. These injuries occur when the patient is hurled by the force of the explosion against a stationary object. A blast wind, sudden change in the surrounding atmosphere, creates a pressure wave.

This can cause the patient's body to be hurled or thrown, resulting in further injury. This physical displacement of the body is also referred to as ground shock when the body impacts. the ground.

Quaternary blast injuries. This category of miscellaneous injuries includes burns from hot gases or fires started by the blast, respiratory injury from inhaling toxic gases, suffocation, poisoning, medical emergencies incurred as a result of the explosion, crush injuries from the collapse of buildings, contamination of wounds from environmental, chemical, or toxic substances, radiation injury from dirty bombs, and mental health emergencies. Essentially, all injuries due to the blast event that are not attributable directly to a primary, secondary, or tertiary mechanism are categorized as quaternary blast injuries. Most patients who survive an explosion will have some combination of the four types of injuries mentioned. The remainder of the discussion will be confined to primary blast injuries because while secondary blast injuries account for most of the trauma, primary injuries are the ones that are most easily overlooked.

Tissues at risk, hollow organs, those that contain air, such as the middle ear, lung, and gastrointestinal tract, are most susceptible to pressure changes. The junction between tissues of different densities and exposed areas such as head and neck tissues are also susceptible to injury. The ear is the organ system that is most sensitive to blast injuries. The tympanic membrane evolved to detect minor changes in pressure and will rupture at pressures of 5 to 7 pounds per square inch above atmospheric pressure. Thus, the tympanic membranes are a sensitive indicator that you can use to help determine the possible presence of other blast injuries.

The patient may report ringing in the ears, pain in the ears, or some loss of hearing, and blood may be visible in the ear canal. Dislocation of structural components of the ear, such as the ossicles conforming the inner ear, may occur. Permanent hearing loss is possible. These findings can be used to assist in triaging patients as they indicate risk of pressure injuries to the lungs.

Pulmonary blast injuries are defined as pulmonary trauma, consisting of contusions. and hemorrhages that results from short-range exposure to the detonation of explosives. When the explosion occurs in an open space, both lungs are usually injured. Primary blast injury is often characterized by a lack of external visible injuries, and thus can go unrecognized. The patient may report tightness or pain in the chest, and may cough up blood, and have tachypnea or other signs of respiratory distress, subcutaneous emphysema, crackling under the skin.

can be palpated over the chest, indicating air in the thorax. Pneumothorax is a common injury, and may require emergency decompression, which is covered in Chapter 30, Chest Injuries, in the field for your patient to survive. Pulmonary edema may ensue rapidly. If there is any reason to suspect lung injury in a blast victim, even just the presence of a ruptured eardrum, administer oxygen to maintain oxygen saturation of 94% to 99%. Avoid giving oxygen under positive pressure, however, because that may simply increase the damage to the lung or increase the size of a pneumothorax.

One of the most concerning pulmonary blast injuries is arterial air embolism, which occurs on alveolar disruption with subsequent air embolization into the pulmonary vasculature. Even small air bubbles can enter a coronary artery and cause myocardial injury. Air embolisms to the cerebrovascular system can produce disturbances in vision, changes in behavior, changes in state of consciousness, and a variety of other neurologic signs.

Solid organs are relatively protected from shock wave injury but may be injured by secondary missiles or a hurled body. Hollow organs, however, may be injured by the same mechanisms that damage lung tissue, skin injuries, ranging from petechiae. or pinpoint red-purple hemorrhages that show up on the skin, to large hematomas may be found.

Perforation or rupture of the bowel and colon is a risk. Underwater explosions can result in severe abdominal injuries. Neurologic injuries and head trauma are the most common causes of death from blast injuries related to terrorist incidents. Subarachnoid, beneath the arachnoid layer covering the brain, and subdural, beneath the outermost covering of the brain. Hematomas are often seen.

Permanent or transient neurologic deficits may be secondary to concussion, intracerebral bleeding, or air embolism. Instant but transient unconsciousness, with or without retrograde amnesia, may be initiated not only by head trauma, but also by cardiovascular problems. Bradycardia and hypotension are common after an intense pressure wave from an explosion. Extremity injuries, including traumatic amputations.

are common. Patients with traumatic amputation by post-blast wind are likely to sustain fatal injuries secondary to the blast. In present-day combat, improved body armor has increased the number of survivors of blast injuries from shrapnel wounds to the torso. The number of severe orthopedic and extremity injuries, however, has increased. In addition, whereas body armor may limit or prevent shrapnel from entering the body.

It also catches more energy from the blast wave, possibly resulting in the victim being thrown backward, thus increasing the potential for spine and spinal cord injury. Although blast injuries have usually occurred in war zones, they often occur in industrial settings, and are, unfortunately, currently more common because of the increased use of explosives as a tool for urban terrorism and, in the United States, from methamphetamine laboratory explosions. Although civilian blast injuries in an industrial or mining setting used to be mostly characterized by blast injuries and burns, terrorist bombs often contain shrapnel. As an emergency medical technician, you and other emergency medical service and trauma services personnel should be fully educated and aware of what to expect in these scenarios. Multi-system trauma.

Multi-system trauma is a term that describes a person who has been subjected to multiple traumatic injuries involving more than one body system, such as head, and spinal trauma, chest and abdominal trauma, or chest and multiple extremity trauma. You must recognize patients who fit into this classification, and provide rapid treatment and transportation, and alert medical control as to the nature of the patient's injuries so that the trauma center is prepared prior to your arrival. Multi-system trauma patients have a high level of morbidity and mortality.

Therefore, they require teams of physicians to treat their injuries. Golden principles of pre-hospital trauma care. As with any emergency medical service call, your main priority in managing multi-system trauma is to ensure your safety, and the safety of your crew and patient. Next, you must determine the need for additional personnel or equipment, evaluate the mechanism of injury. and identify and appropriately manage life threats.

Once these steps have been completed, you can focus on patient care. Hemorrhage control has the highest priority. Severe bleeding from partial or complete amputations or other large wounds must be stopped.

A tourniquet should be applied when bleeding from an extremity cannot be controlled using direct pressure, as discussed in Chapter 26, Bleeding. Assessing and Managing the Airway and Breathing including ventilatory support and high flow oxygen, while maintaining appropriate spinal motion restriction is the second priority. Ensure that other shock therapy, such as keeping the patient warm, is completed. Initiate spinal motion restriction precautions as indicated.

If the patient is entrapped, consider the use of rapid extrication techniques. In most patients with multi-system trauma, definitive care requires surgical intervention, therefore, Unseen time should be limited to 10 minutes or less, referred to as the platinum 10. During transport, obtain a signs and symptoms, allergies, medications, pertinent past medical history, last oral intake, events leading up to the illness or injury history, and complete a secondary assessment. Most care can be provided during transport.

However, keep in mind that your patient has sustained multi-system trauma. and the order in which you usually provide treatment and care may need to be adjusted depending on the needs of the patient. For critically injured patients, consider advanced life support intercept and or air medical transportation.

Regardless of the mode of transport, ensure that the patient is transported to an appropriate facility, and that the facility is notified as soon as possible. Specific standards of care regarding multi-system trauma are addressed in detail in the respective chapters. Patient Assessment.

Identifying life-threatening illnesses and injuries as soon as possible has proven to improve patient outcomes. As an emergency medical technician, you must apply this knowledge as well as the appropriate assessment skills to assess, triage, manage, and transport patients with traumatic injuries to the most appropriate facility. The major components of patient assessment include the following.

Scene Size Up. Primary Assessment. History taking, secondary assessment, reassessment.

When you are caring for a patient who has experienced a significant mechanism of injury and the patient is considered to be in serious or critical condition, you should rapidly perform a physical examination. With a patient who has experienced a non-significant mechanism of injury, focus on the chief complaint while assessing the patient as a whole. The human body is divided into areas, or systems, based on body function, and its internal organs are subject to unseen injuries when force is applied to the body. For example, the brain may have bruising, the heart and lungs may have bruising or unseen bleeding, and the organs of the abdomen may have life-threatening bleeding.

The following sections discuss the assessment of various body systems. Injuries to the head. The brain lies well protected within the skull. However, when the head is injured from trauma, disability and unseen injury to the brain may occur.

The brain itself may tear or become bruised, causing bleeding. The blood vessels around the brain may also tear and produce bleeding. Bleeding or swelling inside the skull from brain injury is often life-threatening. Therefore, your assessment must include conducting frequent neurologic examinations. Neurologic assessments, coupled with the patient's level of consciousness, will often provide details on subtle changes in the patient's condition.

Some patients will not have obvious signs or symptoms, such as changes in pupillary size and reactivity, of unseen brain injury until minutes or hours after the injury has occurred. Injuries to the neck and throat. The neck and throat contain many structures that are susceptible to injuries from trauma that could be serious or deadly to your patients.

In this region of the human body, the trachea, or windpipe, may become torn or swell after an injury to the neck or deviate after an injury to the lungs. These types of injuries may result in an airway problem that could quickly become a serious life threat because they interfere with the patient's ability to breathe. Therefore, Your assessment must include frequent physical examination looking for decap-BTLS in the neck region. In addition, you should assess for jugular venous, vein, distension and tracheal deviation, late sign of injury. The neck also contains large blood vessels that supply the brain with oxygen-rich blood.

When a neck injury occurs, swelling may prevent blood flow to the brain and cause injury to the central nervous system. Even though the brain may not have been directly affected by the initial force that caused the injury to the neck, if a penetrating injury to the neck results in an open wound, the patient may have significant bleeding or air may be drawn into the circulatory system. If air enters the veins, this may result in air embolism, which may lead to cardiac arrest if the air enters the heart. Occlusive dressings must be used to keep this from happening.

A crushing injury to the upper part of the neck may cause the cartilages of the upper airway and larynx to fracture. This can lead to air leaking into the soft tissue of the neck. When air is trapped in subcutaneous tissue, subcutaneous emphysema, it produces a crackling sound or feeling when palpated, called subcutaneous crepitation. Either air in the circulation or an airway cartilage fracture may cause rapid death.

Injuries to the chest. The chest contains the heart. the lungs, and the large blood vessels of the body.

When injury occurs to this area of the body, many life-threatening injuries may occur. For example, blunt trauma to the chest can fracture ribs or the sternum. When ribs are broken, and the chest wall does not expand normally during breathing, this interferes with the body's ability to obtain sufficient amounts of oxygen for the cells.

Bruising may occur to the heart and cause an irregular heartbeat. Depending on the severity of the trauma, the large vessels of the heart may be torn inside the chest, causing massive unseen bleeding that can quickly kill the trauma patient. In some chest injuries the lungs become bruised, thus interfering with normal oxygen exchange in the body. Some chest injuries result in air collecting between the lung tissue, and the chest wall.

As air accumulates in this space, the lung tissue becomes compressed. again interfering with the body's ability to effectively exchange oxygen. This injury is called a pneumothorax. If left untreated or unrecognized, the lung tissue becomes squeezed under pressure until the heart is also squeezed and can no longer pump blood. This condition is called a tension pneumothorax, and is a life-threatening emergency.

In some patients, bleeding develops in this portion of the chest, instead of air collecting in this space. Blood collects and causes interference with breathing. This condition is called a hemothorax, and it also poses a threat to the patient's life. A penetration or perforation of the integrity of the chest is called an open chest wound. As air enters the chest cavity, the natural pressure balance within the chest cavity is no longer equal.

If left untreated, shock and or death will result, regardless of the particular injury. It is imperative that you reassess a trauma patient's chest region every five minutes. The assessment should include decap-BTLS, lung sounds, and chest rise and fall. Some patients will not have obvious signs or symptoms such as absent breath sounds or respiratory difficulty immediately.

Injuries to the abdomen The abdomen is an area of the human body that contains many organs vital to body function. These organs also require a high blood pressure. flow so they can perform the functions necessary for life. The organs of the abdomen and retroperitoneum, the space immediately behind the true abdomen, can be classified into two simple categories, solid and hollow.

The solid organs include the liver, spleen, pancreas, and kidneys. The hollow organs include the stomach, large and small intestines, and urinary bladder. When injuries from trauma occur in this region of the body, serious and life-threatening problems may occur the solid organs may tear lacerate or fracture this causes serious bleeding into the abdomen that can quickly cause death be alert for a trauma patient who reports abdominal pain it may be a symptom of abdominal bleeding also be alert to vital signs that begin to worsen this can be a sign of serious unseen bleeding inside the abdominal region of the body When the hollow organs of the body have been injured, they may rupture and leak toxic chemicals used for digestion into the abdomen. This not only causes pain, but a life-threatening infection also may eventually develop. The abdomen also contains large blood vessels that supply the organs of this region, and the lower extremities with oxygen-rich blood.

Occasionally these vessels rupture or tear and cause serious unseen bleeding that may cause death. Some patients particularly healthy young adults, are able to compensate longer than others from blood loss. Therefore, you should always maintain a high index of suspicion when the mechanism of injury suggests injury to the abdominal region. This is best accomplished by reassessing the abdominal region.

Management, transport and destination. Caring for victims of traumatic injuries requires a solid understanding of the trauma system in the United States. You need a good working knowledge of the resources available to you, including the most optimal methods of rapid transport and trauma centers that can best provide definitive care.

Call for advanced life support and helicopter assistance early, possibly even before you arrive on scene, to avoid delays in treatment and transport. Scene time. Because survival of critically injured trauma patients is time dependent. Limit on-scene time to the minimum amount necessary to correct life-threatening injuries and package the patient.

Optimally, on-scene time for critically injured patients should be less than 10 minutes, the platinum 10. The following criteria will help you identify a critically injured patient. Dangerous mechanism of injury. Decreased level of consciousness.

Any threats to airway, breathing, or circulation. Patients who present with these criteria or who are very young or old or have chronic illnesses should also be considered to be high risk, thus requiring rapid treatment, and transport. Destination Selection You will often be summoned to injury scenes to transport critically ill trauma patients to definitive care.

For this reason, it is important for you to be familiar with how the American College of Surgeons Committee on Trauma classifies trauma care. Trauma centers are classified into levels 1 through 4, with level 1 having the most resources, followed by levels 2, 3, and 4. A level 1 facility is a regional resource center, and generally serves large cities or heavily populated areas. Level 1 facilities must be capable of providing every aspect of trauma care from prevention through rehabilitation.

Therefore, the facility must have adequate personnel and resources. Because of the extensive requirements, most Level 1 facilities are university-based teaching hospitals. A Level 2 facility is typically located in less populated areas. Level 2 centers are expected to provide initial definitive care, regardless of injury severity. These facilities can be academic institutions or a public or private community facility, because of its location and resources.

A level 2 trauma center may not be able to provide the same comprehensive care as a level 1 trauma center. Level 3 facilities serve communities that do not have access to level 1 or 2 facilities. Level 3 facilities provide assessment, resuscitation, emergency care, and stabilization.

A level 3 facility must have transfer agreements with a level 1 or 2 trauma center. and must have protocols in place to transfer patients whose needs exceed the resources of the facility. Level 4 facilities are typically found in remote outlying areas where no higher level of care is available. These facilities provide ADLS prior to transfer to a higher level trauma center.

Such a facility may be a clinic urgent care facility, with or without a physician. Although an inclusive trauma system should leave no facility without a direct link to a level 1 or 2 facility, all facilities are expected to provide the same high quality of initial care regardless of the classification level. Trauma centers are categorized as either adult trauma centers or pediatric trauma centers, but not necessarily both. Pediatric trauma centers are not nearly as common as adult trauma centers.

When transporting a pediatric trauma patient, You must be certain to transport your patient to a pediatric trauma center if there is one in your area. Do not make the mistake of transporting a pediatric patient to an adult trauma center when a pediatric trauma center is available. In 2011, the American College of Surgeons Committee on Trauma in the Centers for Disease Control published an updated field triage decision scheme. These criteria are intended to help pre-hospital care providers recognize injured patients who are likely to benefit from transport to a trauma center compared with transport to an emergency department. The decision scheme is not intended to serve as a mass casualty or disaster triage tool.

It is intended only for individual patients. Type of transport. Modes of transport ultimately come in one of two categories, ground or air. Transport modes are discussed further in Chapter 15, Medical Overview.

Ground Transportation Emergency Medical Service Units are generally staffed by emergency medical technicians and paramedics. Air Transportation Emergency Medical Service Units or Critical Care Transport Units are often staffed by critical care transport professionals such as critical care nurses and paramedics. You should be familiar with your local protocols defining indications for use of helicopter emergency medical services transport.

In 2014, an expert panel developed evidence-based guidelines for the appropriate use of emergency air medical services for trauma patients. Field triage criteria for trauma patients should include anatomic, physiologic, and situational components based on the Centers for Disease Control's 2011 Guidelines for the Field Triage of Injured Patients. These guidelines help predict injury severity to determine the need for helicopter or ground ambulance transport.

When it is not clear that the patient meets the guidelines for severity, medical direction should be consulted to determine the appropriate means of transport for the patient. Factors to consider when determining whether the patient is seriously injured include the following. There is an extended period required to access or extricate a remote, for example, injured hiker, snowmobiler, or boater, or trapped patient, for example, in a crashed car, who has evidence of serious injury, and this access or extrication depletes the time window to get the patient to the trauma center by ground.

The patient needs medical care and stabilization at the advanced life support level, and there is no advanced life support level ground ambulance service available within a reasonable time frame. Traffic conditions or hospital availability make it unlikely that the seriously injured patient will get to a trauma center via ground ambulance within the ideal time frame for best clinical outcome. There is a mass casualty incident with serious injuries. These recommendations are not to be understood as fully encompassing, but more as a guideline for local decision makers to develop more comprehensive protocols for the use of helicopter emergency medical services transport.

Always follow your local protocols when determining what type of patient transportation is appropriate. Special considerations. Because traumatic injuries are as varied as the mechanisms that cause them.

It is almost impossible to prepare for every possible situation that you may face during your career. In all situations, you must remain calm, complete an organized assessment, correct life-threatening injuries, and do no harm. You should never hesitate to contact Advanced Life Support Backup or Medical Control for guidance.

Transcript for:Trauma Overview and Pre-Hospital Care

Transcript for:
Trauma Overview and Pre-Hospital Care