Transcript Geratric Radiography Positioning

Geratric Radiography Positioning
Chest
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.
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.
Spine
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.
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
Pelvis
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
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