TRAUMA RADIOGRAPHY

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TRAUMA RADIOGRAPHY





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Introduction


Trauma is defined as a severe injury or damage to the body caused by an accident or violence. Victims of trauma require immediate and specialized care, which is commonly provided in larger hospitals within a specialized unit, termed the emergency department (ED). Physicians and many nurses specialize in trauma care. Imaging professionals are essential to the diagnosis of the injuries sustained during traumatic events, so extra study in this area of imaging is necessary. Trauma radiography can be an exciting and challenging environment for a properly prepared imaging professional. These procedures can be intimidating and stressful for individuals unprepared for the myriad injuries seen in the ED. The essential key to quality imaging procedures for trauma patients is proper study and preparation for imaging professionals.


Preparation for the trauma environment requires an understanding of the following: the most common traumatic injuries, the most commonly affected populations, the types of trauma care facilities, the specialized imaging equipment designed for imaging of trauma patients, the role of the imaging technologist as part of the ED team, and the common imaging procedures performed on trauma patients. This chapter provides the information necessary to improve the skills and confidence of all imaging professionals caring for trauma patients.



Trauma Statistics


Trauma-related injuries affect persons in all age ranges. Fig. 13-1 shows trauma incidence by age and gender, as reported by the American College of Surgeons’ National Trauma Database (NTDB) 2008 annual report. The database contains greater than 3 million records from more than 400 hospitals and has received information from across the United States. These data show that trauma patients most commonly are male, ranging in age from teenagers to early adults. Fig. 13-2 shows the distribution of trauma injuries by cause, with the most common being motor vehicle accidents (MVAs). Firearms rank next to last as a cause of injury; however, the 2008 NTDB report also shows that firearms have the highest fatality rate The data show the most common trauma patients and mechanisms of injury, but the imaging professional who chooses to work in the ED must be prepared to care for patients from every age range exhibiting a vast array of injuries.




Many types of facilities provide emergency medical care ranging from major medical centers to small outpatient clinics in rural areas. The term trauma center denotes a specific level of emergency medical care as defined by the American College of Surgeons Commission on Trauma. Four levels of care are defined. Level I is the most comprehensive, and Level IV is the most basic. A Level I center is usually a university-based center, research facility, or large medical center. It provides the most comprehensive emergency medical care available with complete imaging capabilities 24 hours per day. All types of specialty physicians are available on site 24 hours per day. Radiographers are also available 24 hours per day. A Level II center probably has all of the same specialized care available but differs in that it is not a research or teaching hospital, and some specialty physicians may not be available on site. Level III centers are usually located in smaller communities where Level I or Level II care is unavailable. Level III centers generally do not have all specialists available but can resuscitate, stabilize, assess, and prepare a patient for transfer to a larger trauma center. A Level IV center may not be a hospital at all, but rather a clinic or outpatient setting. These facilities usually provide care for minor injuries and offer stabilization and arrange for transfer of more serious injuries to a larger trauma center.


Several types of forces, including blunt, penetrating, explosive, and heat, result in injuries. Examples of blunt trauma are MVAs, which include motorcycle accidents and collisions with pedestrians; falls; and aggravated assaults. Penetrating trauma includes gunshot wounds (GSWs), stab wounds, impalement injuries, and foreign body ingestion or aspiration. Explosive trauma causes injury by several mechanisms including pressure shock waves, high-velocity projectiles, and burns. Burns may be caused by numerous agents including fire, steam and hot water, chemicals, electricity, and frostbite.



Preliminary Considerations



SPECIALIZED EQUIPMENT


Time is a crucial element in the care of a trauma patient. To minimize the time needed to acquire diagnostic x-ray images, many EDs have dedicated radiographic equipment located in the department or immediately adjacent to the department. Trauma radiographs must be taken with minimal patient movement, requiring more maneuvering of the tube and image receptor (IR). Specialized trauma radiographic systems are available and are designed to provide greater flexibility in x-ray tube and IR maneuverability (Fig. 13-3). These specialized systems help to minimize movement of the injured patient while performing imaging procedures. Additionally, some EDs are equipped with specialized beds or stretchers that have a movable tray to hold the IR. This type of stretcher allows the use of a mobile radiographic unit and eliminates the requirement and risk of transferring an injured patient to the radiographic table.



Computed tomography (CT) is widely used for imaging of trauma patients. In many cases, CT is the first imaging modality used, now that image acquisition has become almost instantaneous. (Refer to Chapter 31 in Volume 3 for a detailed explanation and description of CT.) The only major concern with CT imaging compared with radiography is the radiation dose. The debate centers on the exclusive use of CT, when lower dose radiographs may be sufficient to make a diagnosis. Patients who are at high risk and who are not good candidates for quality radiographs owing to their injuries may be referred to CT first.


Mobile radiography is often a necessity in the ED. Many patients have injuries that prohibit transfer to a radiographic table, or their condition may be too critical to interrupt treatment. Trauma radiographers must be competent in performing mobile radiography on almost any part of the body and be able to use accessory devices (i.e., grids, air-gap technique) necessary to produce quality mobile images.


Mobile fluoroscopy units, usually referred to as C-arms because of their shape, are becoming more commonplace in EDs. C-arms are used for fracture reduction procedures, foreign body localization in limbs, and reduction of joint dislocations (Fig. 13-4).



An emerging imaging technology has the potential to have a significant effect on trauma radiography. The Statscan (Lodox Systems [Pty], Ltd.) is a relatively new imaging device that produces full-body imaging scans in approximately 13 seconds without moving the patient (Figs. 13-5 to 13-7). There are at present approximately 17 of these systems worldwide. At a cost of approximately $450,000, this technology is an expensive addition to trauma imaging.





Positioning aids are essential to quality imaging in trauma radiography. Sponges, sandbags, and the creative use of tape are often the trauma radiographer’s most useful tools. Most patients who are injured cannot hold the required positions because of pain or impaired consciousness. Other patients cannot be moved into the proper position because to do so would exacerbate their injury. Proper use of positioning aids assists in quick adaptation of procedures to accommodate the patient’s condition.


Grids and IR holders are necessities because many projections require the use of a horizontal central ray. Grids should be inspected routinely because a damaged grid often causes image artifacts. IR holders enable the radiographer to perform cross-table lateral projections (dorsal decubitus position) on numerous body parts with minimal distortion. To prevent unnecessary exposure, ED personnel should not hold the IR.



EXPOSURE FACTORS


Patient motion is always a consideration in trauma radiography. The shortest possible exposure time that can be set should be used in all procedures except when a breathing technique is desired. Unconscious patients cannot suspend respiration for the exposure. Conscious patients are often in extreme pain and unable to cooperate for the procedure.


Radiographic exposure factor compensation may be required when making exposures through immobilization devices such as a spine board or backboard. Most trauma patients arrive at the hospital with some type of immobilization device (Fig. 13-8). Pathologic changes should also be considered when setting technical factors. Internal bleeding in the abdominal cavity would absorb a greater amount of radiation than a bowel obstruction.




POSITIONING OF THE PATIENT


The primary challenge of the trauma radiographer is to obtain a high-quality, diagnostic image on the first attempt when the patient is unable to move into the desired position. Many methods are available to adapt a routine projection and obtain the desired image of the anatomic part. To minimize the risk of exacerbating the patient’s condition, the x-ray tube and IR should be positioned, rather than the patient or the part. The stretcher can be positioned adjacent to the vertical Bucky or upright table as the patient’s condition allows (Fig. 13-9). This location enables accurate positioning with minimal patient movement for cross-table lateral images (dorsal decubitus positions) on numerous parts of the body. Additionally, the grid in the table or vertical Bucky is usually a higher ratio than that used for mobile radiography, so image contrast is improved. Another technique to increase efficiency, while minimizing patient movement, is to take all of the AP projections of the requested examinations moving superiorly to inferiorly. All of the lateral projections of the requested examinations are then performed moving inferiorly to superiorly. This method moves the x-ray tube in the most expeditious manner.



When taking radiographs to localize a penetrating foreign object, such as metal or glass fragments or bullets, the entrance and exit wounds should be marked with a radiopaque marker that is visible on all projections (Fig. 13-10). Two exposures at right angles to each other show the depth and the path of the projectile.




Radiographer’s Role as Part of the Trauma Team


The role of the radiographer within the ED ultimately depends on the department protocol and staffing and the extent of emergency care provided at the facility. Regardless of the size of the facility, the primary responsibilities of a radiographer in an emergency situation include the following:



Ranking these responsibilities is impossible because they occur simultaneously, and all are vital to quality care in the ED.




RADIATION PROTECTION


One of the most essential duties and ethical responsibilities of the trauma radiographer is radiation protection of the patient, members of the trauma team, and the radiographer himself or herself. In critical care situations, members of the trauma team cannot leave the patient while imaging procedures are being performed. The trauma radiographer must ensure that the other team members are protected from unnecessary radiation exposure. Common practices should minimally include the following:



Consideration must also be given to patients on nearby stretchers. If these patients are less than 6 ft away from the x-ray tube, appropriate shielding should be provided. Some of the greatest exposures to patients and medical personnel are from fluoroscopic procedures. If the C-arm fluoroscopic unit is used in the ED, special precautions should be in place to ensure that fluoroscopic exposure time is kept to a minimum and that all personnel are wearing protective aprons.



PATIENT CARE


As with all imaging procedures, trauma procedures require a patient history. The patient may provide this history, if he or she is conscious, or the attending physician may inform the radiographer of the injury and the patient’s status. If the patient is conscious, the radiographer should explain what he or she is doing in detail and in terms the patient can understand. The radiographer should listen to the patient’s rate and manner of speech, which may provide insight into the patient’s mental and emotional status. The radiographer should make eye contact with the patient to provide comfort and reassurance. A trip to the ED is an emotionally stressful event, regardless of the severity of injury or illness.


Radiographers are often responsible for the total care of the trauma patient while performing diagnostic imaging procedures. It is crucial that the radiographer constantly assess the patient’s condition, recognize any signs of decline or distress, and report any change in the status of the patient’s condition to the attending physician. The trauma radiographer must be well versed in taking vital signs and knowing normal ranges and must be competent in cardiopulmonary resuscitation (CPR), administration of oxygen, and dealing with all types of medical emergencies. The radiographer must be prepared to perform these procedures when covered by a standing physician’s order or as departmental policy allows. The radiographer also should be familiar with the location and contents of the adult and pediatric crash carts and understand how to use the suctioning devices.


The familiar ABCs (airway, breathing, and circulation) of basic life support techniques must be constantly assessed during the radiographic procedures. Visual inspection and verbal questioning enable the radiographer to determine whether the status of the patient changes during the procedure. Table 13-1 provides a guide for the trauma radiographer regarding changes in status that should be reported immediately to the attending physician. Table 13-1 includes only the common injuries in which the radiographer may be the only health care professional with the patient during the imaging procedure. Patients with multiple trauma injuries and patients in respiratory or cardiac arrest usually are imaged with a mobile radiographic unit while ED personnel are present in the room. In these situations, the primary responsibility of the trauma radiographer is to produce quality images in an efficient manner while practicing ethical radiation protection measures.



TABLE 13-1


Guide for reporting patient status change


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*Hypovolemic or hemorrhagic shock is a medical condition in which there are abnormally low levels of blood plasma in the body, such that the body cannot properly maintain blood pressure, cardiac output of blood, and normal amounts of fluid in the tissues. It is the most common type of shock in trauma patients. Symptoms include diaphoresis, cool and clammy skin, decrease in venous pressure, decrease in urine output, thirst, and altered state of consciousness.


†Vasovagal reaction is also called a vasovagal attack, situational syncope, and vasovagal syncope. It is a reflex of the involuntary nervous system or a normal physiologic response to emotional stress. Patients may complain of nausea, feeling flushed (warm), and feeling lightheaded. They may appear pale before they lose consciousness for several seconds.


‡Cerebrovascular accident (CVA) is commonly called a stroke and may be caused by thrombosis, embolism, or hemorrhage in the vessels of the brain.


§Drugs or alcohol. Patients under the influence of drugs or alcohol or both commonly present in the ED. In this situation, the usual symptoms of shock and head injury are unreliable. Be on guard for aggressive physical behaviors and abusive language.


||Hyperglycemia is also known as diabetic ketoacidosis. The cause is increased blood glucose levels. The patient may exhibit any combination of symptoms noted and has fruity-smelling breath.


Pelvic fractures have a high mortality rate (mortality with open fractures may be 50%). Hemorrhage and shock are often associated with this type of injury.



Best Practices in Trauma Radiography


Radiography of the trauma patient seldom allows the use of “routine” positions and projections. Additionally, the trauma patient requires special attention to patient care techniques while performing difficult imaging procedures. The following best practices provide some universal guidelines for the trauma radiographer:



1. Speed: Trauma radiographers must produce quality images in the shortest amount of time. Rapidity in performing a diagnostic examination is crucial to saving the patient’s life. Many practical methods that increase examination efficiency without sacrificing image quality are introduced in this chapter.


2. Accuracy: Trauma radiographers must provide accurate images with a minimal amount of distortion and the maximum amount of recorded detail. Alignment of the central ray, the part, and the IR also applies in trauma radiography. Using the shortest exposure time minimizes the possibility of imaging involuntary and uncontrollable patient motion.


3. Quality: Quality does not have to be sacrificed to produce an image quickly. The patient’s condition should not be used as an excuse for careless positioning and accepting less than high-quality images.


4. Positioning: Careful precautions must be taken to ensure that performance of the imaging procedure does not exacerbate the patient’s injuries. The “golden rule” of two projections at right angles from one another still applies. As often as possible, the radiographer should position the tube and the IR, rather than the patient, to obtain the desired projections.


5. Practice standard precautions: Exposure to blood and body fluids should be expected in trauma radiography. The radiographer should wear gloves, mask, eye shields, and gown when appropriate. IR and sponges should be placed in nonporous plastic to protect them from body fluids. Hand hygiene should be performed frequently, especially between patients. All equipment and accessory devices should be kept clean and ready for use.


6. Immobilization: The radiographer should never remove any immobilization device without physician’s orders. The radiographer should provide proper immobilization and support to increase patient comfort and to minimize risk of motion.


7. Anticipation: Anticipating required special projections or diagnostic procedures for certain injuries makes the radiographer a vital part of the ED team. Patients requiring surgery generally require an x-ray of the chest. In facilities where CT is not readily available for emergency patients, fractures of the pelvis may require a cystogram to determine the status of the urinary bladder. The radiographer should know which procedures are often referred to CT first or for additional images. Being prepared for and understanding the necessity of these additional procedures and images instills confidence in, and creates an appreciation for, the role of the radiographer in the emergency setting.


8. Attention to detail: The radiographer should never leave a trauma patient (or any patient) unattended during imaging procedures. The patient’s condition may change at any time, and it is the radiographer’s responsibility to note these changes and report them immediately to the attending physician. If the radiographer cannot process images while maintaining eye contact with the patient, he or she should call for help. Someone must be with the injured patient at all times.


9. Attention to department protocol and scope of practice: The radiographer should know department protocols and practice only within his or her own competence and abilities. The scope of practice for radiographers varies from state to state and from country to country. The radiographer should study and understand the scope of his or her role in the emergency setting. The radiographer should not provide or offer a patient anything by mouth. The radiographer should always ask the attending physician before giving the patient anything to eat or drink, no matter how persistent the patient may be.


10. Professionalism: Ethical conduct and professionalism in all situations and with every person is a requirement of all health care professionals, but the conditions encountered in the ED can be particularly complicated. The radiographer should adhere to the Code of Ethics for Radiologic Technologists (see Chapter 1) and the Radiography Practice Standards. The radiographer should be aware of the people present or nearby at all times when discussing a patient’s care. The ED radiographer is exposed to myriad tragic conditions. Emotional reactions are common and expected but must be controlled until the emergency care of the patient is complete.



Radiographic Procedures in Trauma


The projections included in this chapter result from a telephone survey of Level I trauma centers. The results indicated that the common radiographic projections ordered for initial trauma surveys are as follows1:



Skull radiographs did not rank as one of the most common imaging procedures performed in the ED of Level I trauma centers. Most Level I trauma centers have replaced conventional trauma skull radiographs (e.g., AP, lateral, Towne, reverse Waters) with CT scan of the head (Fig. 13-11). Research articles continue to delineate the advantages of CT over radiography, and the results indicate that certain types of head trauma should be referred to CT first. Smaller facilities may not have CT readily available, however. Trauma skull positioning remains valuable knowledge for the radiographer.



This section provides trauma positioning instructions for radiography projections of the following body areas:



In addition to the dorsal decubitus positions, AP projections of the thoracic and lumbar spine are usually required for trauma radiographic surveys. AP projections of this anatomy vary minimally in the trauma setting and are not discussed in detail. Critical study and clinical practice of these procedures should adequately prepare a radiographer for work in the ED. Certain criteria apply in all trauma imaging procedures and are explained next and not included on each procedure in detail.



PATIENT PREPARATION


Remembering that the patient has endured an emotionally disturbing and distressing event in addition to the physical injuries he or she may have sustained is important. If the patient is conscious, speak calmly and look directly in the patient’s eyes while explaining the procedures that have been ordered. Do not assume that the patient cannot hear you, even if he or she cannot or will not respond.


Check the patient thoroughly for items that might cause an artifact on the images. Explain what you are removing from the patient and why. Place all removed personal effects, especially valuables, in the proper container used by the facility (i.e., plastic bag) or in the designated secure area. Each facility has a procedure regarding proper storage of a patient’s personal belongings. Know the procedure and follow it carefully.



BREATHING INSTRUCTIONS


Most injured patients have difficulty following the recommended breathing instructions for routine projections. For these patients, exposure factors should be set using the shortest possible exposure time to minimize motion on the radiograph, necessitating use of the large focal spot. The decreased resolution of the large focal spot produces greater resolution than the significant loss of resolution from patient movement. If a breathing technique is desired, this can be explained to a conscious trauma patient in the usual manner. If the patient is unconscious or unresponsive, careful attention should be paid to the rate and degree of chest wall movement. If inspiration is desired on the image, the exposure should be timed to correspond to the highest point of chest expansion. Conversely, if the routine projection calls for exposure on expiration, the exposure should be made when the patient’s chest wall falls to its lowest point.



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Mar 3, 2016 | Posted by in GENERAL RADIOLOGY | Comments Off on TRAUMA RADIOGRAPHY

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