geratric radiography positioning. the position of choice for the chest radiograph is the upright...

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Geratric Radiography Positioning

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Geratric Radiography Positioning

The position of choice for the chest radiograph is the upright position; however, the elderly patient may not be able to stand without assistance for this examination. The traditional posteroanterior (PA) position is to have the “backs of hands on hips.” This may be difficult for someone with impaired balance and flexibility. The radiographer can allow the patient to wrap his or her arms around the chest stand as a means of support and security. The patient may not be able to maintain his or her arms over the head for the lateral projection of the chest. Provide extra security and stability while moving the arms up and forward.

Chest

When the patient cannot stand, the examination may be done seated in a wheelchair, but some issues will affect the radiographic quality. First, the radiologist needs to be aware that the radiograph is an anteroposterior (AP) instead of a PA projection, which may make comparison difficult. Hyperkyphosis can result in the lung apices being obscured, and the abdomen may obscure the lung bases. In a sitting position, respiration may be compromised, and the patient should be instructed on the importance of a deep inspiration.

Positioning of the image receptor for the kyphotic patient should be higher than normal because the shoulders and apices are in a higher position. Radiographic landmarks may change with age, and the centering may need to be lower if the patient is extremely kyphotic. When positioning the patient for the sitting lateral chest projection, the radiographer should place a large sponge behind the patient to lean him or her forward.

Radiographic spine examinations may be painful for the patient suffering from osteoporosis who is lying on the x-ray table. Positioning aids such as radiolucent sponges, sandbags, and a mattress may be used as long as the quality of the image is not compromised. Performing upright radiographic examinations may also be appropriate if a patient can safely tolerate this position. The combination of cervical lordosis and thoracic kyphosis can make positioning and visualization of the cervical and thoracic spine difficult. Lateral cervical projections can be done with the patient standing, sitting, or lying supine. The AP projection in the sitting position may not visualize the upper cervical vertebrae because the chin may obscure this anatomy. In the supine position the head may not reach the table and result in magnification. The AP and open-mouth projections are difficult to do in a wheelchair.

Spine

Positioning sponges and sandbags are commonly used as immobilization devices

The thoracic and lumbar spines are sites for compression fractures. The use of positioning blocks may be necessary to help the patient remain in position. For the lateral projection, a lead blocker or shield behind the spine should be used to absorb as much scatter radiation as possible

Osteoarthritis, osteoporosis, and injuries as the result of falls contribute to hip pathologies. A common fracture in the elderly is the femoral neck. An AP projection of the pelvis should be done to examine the hip. If the indication is trauma, the radiographer should not attempt to rotate the limbs. The second view taken should be a cross-table lateral of the affected hip. If hip pain is the indication, assist the patient to internal rotation of the legs with the use of sandbags if necessary

Pelvis

Legs inverted for an AP projection of the pelvis. Use of flexible sandbags to wrap around the feet can help the geriatric patient hold his or her legs in this position.

TRAUMA

CLEMENTS-NAKAYAMA MODIFICATION

Leonard –George Modification

Upper extremities

Positioning the geriatric patient for projections of the upper extremities can present its own challenges. Often the upper extremities have limited flexibility and mobility. A cerebrovascular accident or stroke may cause contractures of the affected limb. Contracted limbs cannot be forced into position, and cross-table views may need to be done. The inability of the patient to move his or her limb should not be interpreted as a lack of cooperation. Supination is often a problem in patients with contractures, fractures, and paralysis. The routine AP and lateral projections can be supported with the use of sponges, sandbags, and blocks to raise and support the extremity being imaged. The shoulder is also a site of decreased mobility, dislocation, and fractures. The therapist should assess how much movement the patient can do before attempting to move the arm. The use of finger sponges may also help with the contractures of the fingers

Lower extremities

The lower extremities may have limited flexibility and mobility. The ability to dorsiflex the ankle may be reduced as a result of neurologic disorders. Imaging on the x-ray table may need to be modified when a patient cannot turn on his or her side. Flexion of the knee may be impaired and require a cross-table lateral projection. If a tangential projection of the patella, such as the Settegast method, is necessary and the patient can turn on his or her side, place the image receptor superior to the knee and direct the central ray perpendicular through the patellofemoral joint. Projections of the feet and ankles may be obtained with the patient sitting in the wheelchair. The use of positioning sponges and sandbags support and maintain the position of the body part being imaged

CONTRAST ADMINISTRATION

Because of age-related changes in kidney and liver functions, only the amount, not the type, of contrast media is varied when performing radiographic procedures on the elderly patient. The number of functioning nephrons in the kidneys steadily decreases from middle age throughout the life span. Compromised kidney function contributes to the elderly patient being more prone to electrolyte and fluid imbalance, which can create life-threatening consequences. They are also more susceptible to the effects of dehydration because of diabetes and decreased renal or adrenal function.

The decision of type and amount of contrast media used for the geriatric patient usually follows some sort of routine protocol. Assessment for contrast agent administration accomplished by the imaging technologist must include age and history of liver, kidney, or thyroid disease; history of hypersensitivity reactions and previous reactions to medications or contrast agents; sensitivity to aspirin; over-the-counter and prescription drug history including acetaminophen (Tylenol); and history of diabetes and hypertension.1 The imaging technologist must be selective in locating an appropriate vein for contrast administration on the elderly patient. They should consider the location and condition of the vein, decreased integrity of the skin, and duration of the therapy. Thin superficial veins, repeatedly used veins, and veins located in areas where the skin is bruised or scarred should be avoided. Assess the patient for any swallowing impairments, which could lead to difficulties with drinking liquid contrast agents. The patient should be instructed to drink slowly to avoid choking, and an upright position will help prevent aspiration.

TECHNICAL FACTORS

Exposure factors also need to be taken into consideration when imaging the geriatric patient. The loss of bone mass, as well as atrophy of tissues, often requires a lower kilovoltage (kVp) to maintain sufficient contrast. kVp is also a factor in chest radiographs when there may be a large heart and pleural fluid to penetrate. Patients with emphysema require a reduction in technical factors to prevent overexposure of the lung field. Patient assessment can help with the appropriate exposure adjustments