- Reduction of Risk Potential Common Procedures: Diagnostic Tests, Oxygen Therapy, and Hands-on Nursing Care: COMMON DIAGNOSTIC PROCEDURES
- FURTHER READING/STUDY:
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- NCLEX-RN: Infection Control
- NCLEX-RN: Pharmacology
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Reduction of Risk Potential Common Procedures: Diagnostic Tests, Oxygen Therapy, and Hands-on Nursing Care: COMMON DIAGNOSTIC PROCEDURES
Focus topic: Reduction of Risk Potential Common Procedures: Diagnostic Tests, Oxygen Therapy, and Hands-on Nursing Care
I. NONINVASIVE DIAGNOSTIC PROCEDURES are those procedures that provide an indirect assessment of organ size, shape, and/or function; these procedures are considered safe, are easily reproducible, require less complex equipment for recording, and generally do not require the written consent of the client or guardian.
A. General nursing responsibilities:
Focus topic: Reduction of Risk Potential Common Procedures: Diagnostic Tests, Oxygen Therapy, and Hands-on Nursing Care
- Reduce client’s anxieties and provide emotional support by:
a. Explaining purpose and procedure of test.
b. Answering questions regarding safety of the procedure, as indicated.
c. Remaining with client during procedure when possible.
- Use procedures in the collection of specimens that avoid contamination and facilitate diagnosis—clean-catch urine and sputum specimens after deep breathing and coughing, for example.
B. Graphic studies of heart and brain:
Focus topic: Reduction of Risk Potential Common Procedures: Diagnostic Tests, Oxygen Therapy, and Hands-on Nursing Care
- Electrocardiogram (ECG, also known as EKG)— graphic record of electrical activity generated by the heart during depolarization and repolarization; used to: diagnose abnormal cardiac rhythms and coronary heart disease.
- Echocardiography (ultrasound cardiography)— graphic record of motions produced by cardiac structures as high-frequency sound vibrations are echoed through chest wall into the heart; transesophageal echocardiography produces a
clearer image, particularly in clients who are obese, barrel-chested, or with chronic obstructive pulmonary disease (COPD); used to: demonstrate valvular or other structural deformities, detect pericardial effusion, diagnose tumors and cardiomegaly, or evaluate prosthetic valve function.
- Phonocardiogram—graphic record of heart sounds; used to: keep a permanent record of client’s heart sounds before and after cardiac surgery.
- Electroencephalogram (EEG)—graphic record of the electrical potentials generated by the physiological activity of the brain; used to: detect surface
lesions or tumors of the brain and presence of epilepsy.
- Echoencephalogram—beam of pulsed ultrasound is passed through the head, and returning echoes are graphically recorded; used to: detect shifts in cerebral midline structures caused by subdural hematomas, intracerebral hemorrhage, or tumors.
C. Roentgenological studies (x-ray)
- Chest—used to: determine size, contour, and position of the heart; size, location, and nature of pulmonary lesions; disorders of thoracic bones or soft tissue; diaphragmatic contour and excursion; pleural thickening or effusions; and gross changes in the caliber or distribution of pulmonary vasculature.
- Kidney, ureter, and bladder (KUB)—used to: determine size, shape, and position of kidneys, ureters, and bladder.
- Mammography—examination of the breast with or without the injection of radiopaque substance into the ducts of the mammary gland; used to: determine the presence of tumors or cysts. Client preparation: no deodorant, perfume, powders, or ointment in underarm area on day of x-ray. May be uncomfortable due to pressure on the breast.
- Skull—outline configuration and density of brain tissues and vascular markings; used to: determine the size and location of intracranial calcifications, tumors, abscesses, or vascular lesions.
D. Roentgenological studies (fluoroscopy)—require the ingestion or injection of a radiopaque substance to visualize the target organ.
1. Additional nursing responsibilities may include:
- Administration of enemas or cathartics before the procedure and a laxative after.
- Keeping the client NPO 6 to 12 hours before examination; check with physician regarding oral medications.
- Ascertaining client’s history of allergies or allergic reactions (e.g., iodine, seafood).
- Observing for allergic reactions to contrast medium following procedure.
- Providing fluid and food following procedure, to counteract dehydration.
- Observing stool for color and consistency until barium passes.
2. Common fluoroscopic examinations:
a.Upper GI—ingestion of barium sulfate or meglumine diatrizoate (Gastrografin, a white, chalky, radiopaque substance), followed by fluoroscopic and x-ray examination; used to determine:
(1)Patency and caliber of esophagus; may also detect esophageal varices.
(2)Mobility and thickness of gastric walls, presence of ulcer craters, filling defects due to tumors, pressures from outside the stomach, and patency of pyloric valve.
(3)Rate of passage in small bowel and presence of structural abnormalities.
b.Lower GI—rectal instillation of barium sulfate followed by fluoroscopic and x-ray
examination; used to: determine contour and mobility of colon and presence of any space-occupying tumors; perform before upper GI.
Client preparation: explain purpose; no food after evening meal the evening before
test; stool softeners, laxatives, enemas, and suppositories to cleanse the bowel before the test; NPO after midnight before test; oral medications not permitted day of test. After completion of examination: food, increased liquid intake, and rest; laxatives for at least 2 days or until stools are normal in color and consistency.
c. Cholecystogram (done if gallbladder not seen with ultrasound)—ingestion of organic
iodine contrast medium Telepaque (iopanoic acid), or Oragrafin (preparation of calcium or sodium salt of ipodate), followed in 12 hours by x-ray visualization; gallbladder disease is indicated with poor or no visualization of the bladder; accurate only if GI and liver function is intact; perform before barium enema or upper GI.
Client preparation: explain purpose; administer large amount of water with contrast
capsules; low-fat meal evening before x-ray; oral laxative or stool softener after meal;
no food allowed after contrast capsules; water, tea, or coffee, with no cream or sugar usually allowed. After completion of examination: fluids, food, and rest; observe for any signs of allergy to contrast medium.
d. Cholangiogram—intravenous injection of a radiopaque contrast substance, followed by fluoroscopic and x-ray examination of the bile ducts; failure of the contrast medium to pass certain points in the bile duct pinpoints obstruction.
e. Intravenous urography (IVU) or pyelography (IVP)—injection of a radiopaque contrast medium, followed by fluoroscopic and x-ray films of kidneys and urinary tract; used to: identify lesions in kidneys and ureters and provide a rough estimate of kidney function.
f. Cystogram—instillation of radiopaque medium through a catheter into the bladder;
used to: visualize bladder wall and evaluate ureterovesical valves for reflux.
g. Phlebography (lower limb venography)— determines patency of the tibial-popliteal,
superficial femoral, common femoral, and saphenous veins. A contrast medium is injected into the superficial and/or deep veins of the involved extremity, followed by x-rays, while the leg is placed in a variety of positions; used to: detect deep vein thrombosis (DVT) and to select a vein for use in arterial bypass grafting; localized clotting may result.
E. Computed tomography (CT)—an x-ray beam sweeps around the body, allowing measurement of various tissue densities; provides clear radiographic definition of structures that are not visible by other techniques, permitting earlier diagnosis and treatment and more effective and efficient follow-up. Initial scan may be followed by “contrast enhancement” using an injection of an intravenous contrast agent (iodine), followed by a repeat scan.
Client preparation: instructions for eating before test vary. Clear liquids up to 2 hours before are usually permitted.
F. Positron emission tomography (PET)—A radionuclide-based imaging technique. Tracers given IV or by inhalation; rarely intra-arterial. Metabolic and physiological changes are produced by strokes, brain tumors, epilepsy, mental illnesses such as schizophrenia and bipolar disorder, and Parkinson’s disease. PET measures blood flow, glucose metabolism, and oxygen extraction. Useful in: diagnosing myocardial flow deficits and evaluating successful thrombolysis, outcomes of bypass surgery, and percutaneous transluminal coronary angioplasty (PTCA).
Client preparation: fast for 4 hours. Injection of radioactive tracers that emit signals. Must remain motionless for 45 minutes. Scanner is quiet.
G. Magnetic resonance imaging (MRI)—noninvasive, non-ionic technique produces cross-sectional images by exposure to magnetic energy sources. Provides superior contrast of soft tissue, including healthy, benign, and malignant tissue, along with veins and arteries; uses no contrast medium. Takes 30 to 90 minutes to complete; client must remain still for periods of 5 to 20 minutes at a time— equipment often very noisy.
Client preparation: client can take food and medications except for low abdominal and pelvic studies (food/fluids withheld 4 to 6 hours to decrease peristalsis). Restrictions: clients who have metal implants, permanent pacemakers, or implanted medication pumps such as insulin, or who are pregnant or on life support systems. Clients who are obese may not be able to have full-body MRI because they may not fit in the scanner tunnel. Clients who are claustrophobic may need distraction (e.g., music) or may be
referred to a facility that has an MRI chamber that is more open.
H. Multiple gated acquisition (MUGA) scan—also known as blood pool imaging. Red blood cells (RBCs) are tagged with a radioactive isotope. A computer-operated camera takes sequential pictures of actual heart wall motion; complement to cardiac catheterization; used to: determine valvular effectiveness, follow progress of heart disease, diagnose cardiac aneurysms, detect coronary artery disease, determine effects of cardiovascular drug therapy. No special preparation. Painless, except for injections. Wear gloves if contact with client urine occurs within 24 hours after scan.
I. Ultrasound (sonogram)—scanning by ultrasound is used to diagnose disorders of the thyroid, kidney, liver, uterus, gallbladder, and fetus and the intracranial structures in the neonate. It is not useful when visualization through air or bone is required (lung
studies). In some agencies, the sonogram has taken the place of the oral cholecystogram in diagnosing gallbladder disease, bile duct distention, and calculi.
Client preparation is minimal—for example, NPO for at least 8 hours for gallbladder studies. No x-rays. Thirty-two ounces of water PO 30 minutes before studies of lower abdomen or uterus.
J. Pulmonary function studies:
1. Ventilatory studies—utilization of a spirometer to determine how well the lung is ventilating.
- Vital capacity (VC)—largest amount of air that can be expelled after maximal inspiration.
(1)Normally 4,000 to 5,000 mL.
(2)Decreased in restrictive lung disease.
(3)May be normal, slightly increased, or decreased in chronic obstructive lung disease.
- Forced expiratory volume (FEV)—percentage of vital capacity that can be forcibly expired in 1, 2, or 3 seconds.
(1)Normally 81% to 83% in 1 second, 90% to 94% in 2 seconds, and 95% to 97% in 3 seconds.
(2)Decreased values indicate expiratory airway obstruction.
- Maximum breathing capacity (MBC)— maximum amount of air that can be breathed in and out in 1 minute with maximal rate and depth of respiration.
(1)Best overall measurement of ventilatory ability.
(2) Reduced in restrictive and chronic obstructive lung disease.
2. Diffusion studies—measure the rate of exchange of gases across alveolar membrane. Carbon monoxide single-breath, rebreathing, and steady-state techniques—used because of special affinity of hemoglobin for carbon monoxide; decreased when fluid is present in alveoli or when alveolar membranes are thick or fibrosed.
K. Sputum studies:
- Gross sputum evaluations—collection of sputum samples to ascertain quantity, consistency, color, and odor.
- Sputum smear—sputum is smeared thinly on a slide so that it can be studied microscopically; used to: determine cytological changes (malignant
cells) or presence of pathogenic bacteria (e.g., tubercle bacilli).
- Sputum culture—sputum samples are implanted or inoculated into special media; used to: diagnose pulmonary infections.
- Gastric lavage or analysis—insertion of a nasogastric tube into the stomach to siphon out swallowed pulmonary secretions; used to: detect organisms causing pulmonary infections; especially useful for detecting tubercle bacilli in children.
L. Examination of gastric contents:
- Gastric analysis—aspiration of the contents of the fasting stomach for analysis of free and total acid.
a. Gastric acidity is generally increased in presence of duodenal ulcer.
b. Gastric acidity is usually decreased in pernicious anemia, cancer of the stomach.
- Stool specimens—examined for: amount, consistency, color, character, and melena; used to: determine presence of urobilinogen, fat, nitrogen, parasites, and other substances.
M. Thermography—a picture of the surface temperature of the skin using infrared photography (non-ionizing radiation) detects the circulation pattern of areas in the breasts. Tumors produce more heat than normal breast tissue. Useful with large tumors,
but may not detect small or deep lesions. Requires expensive equipment and is difficult to interpret accurately.
N. Doppler ultrasonography—used to: measure blood flow in the major veins and arteries. The transducer of the test instrument is placed on the skin, sending out bursts of ultra-high-frequency sound. The ratio of ankle to brachial systolic pressure (API ≥ 1) provides information about vascular insufficiency. Sound varies with respiration and the Valsalva maneuver. No discomfort to the client.
O. Caloric stimulation test—used to: evaluate the vestibular portion of the eighth cranial nerve, identify the impairment or loss of thermally induced nystagmus. Reflex eye movements (nystagmus) result in response to cold or warm irrigations of the external auditory canal if the nerve is intact. A diminished or absent response occurs with Ménière’s disease or acoustic neuroma. Nausea, vomiting, or dizziness can be precipitated by the test.
P. 24-hour urine collection—a true and accurate evaluation of kidney function, primarily glomerular filtration. Substances excreted by the kidney are excreted at different rates, amounts, and times of day or night. Timed urine collection is done for
protein, creatinine, electrolytes, urinary steroids, etc. A large container is used with or without preservative. Label with client name, type of test, and exact time test starts and ends. Not usually necessary to measure urine. Have client void, discard urine; test starts at this time. Have client void as close to the end of the 24-hour period as possible. If refrigeration is required, urine may be stored in iced container.
Q. Glucose testing—to detect disorder of glucose metabolism, such as diabetes.
- Fasting blood sugar (FBS): blood sample is drawn after a 12-hour fast (usually overnight). Water is allowed. If diabetes is present, value will be 126 mg/dL or greater.
- 2-hour postprandial blood sugar (PPBS): blood is taken after a meal. For best results, client should be on a high-carbohydrate diet for 2 to 4 days before testing. Client fasts overnight, eats a high-carbohydrate breakfast; blood sample is drawn 2 hours after eating. Client should rest during 2-hour interval. Smoking and coffee may increase glucose level.
- Glucose tolerance test (GTT): done when sugar in urine, or FBS or 2-hour PPBS, is not conclusive. A timed test, usually 2 hours. A highcarbohydrate
diet is eaten 3 days before test. Blood is drawn after overnight fast. Client
drinks a very sweet glucose liquid. All of the solution must be taken. Blood and urine samples usually taken at 30 minutes, 1 hour, 2 hours, and sometimes 3 hours after drinking solution. Blood glucose peaks in 30 to 60 minutes, and returns to normal, usually within 3 hours.
II. INVASIVE DIAGNOSTIC PROCEDURES— procedures that directly record the size, shape, or function of an organ and that are often complex or expensive or require utilization of highly trained personnel; these procedures may result in morbidity and
occasionally death of the client and therefore require the written consent of the client or guardian.
A. General nursing responsibilities:
1. Before procedure: institute measures to provide for client’s safety and emotional comfort.
- Have client sign permit for procedure.
- Ascertain and report any client history of allergy or allergic reactions.
- Explain procedure briefly, and accurately advise client of any possible sensations, such as flushing or a warm feeling, as when a contrast medium is injected.
- Keep client NPO 6 to 12 hours before procedure if anesthesia is to be used.
- Allow client to verbalize concerns, and note attitude toward procedure.
- Administer preprocedure sedative, as ordered.
- If procedure done at bedside:
(1)Remain with client, offering frequent reassurance.
(2) Assist with optional positioning of client.
(3)Observe for indications of complications— shock, pain, or dyspnea.
2. After procedure: institute measures to avoid complications and promote physical and emotional comfort.
- Observe and record vital signs.
- Check injection, cut down, or biopsy sites for bleeding, infection, tenderness, or thrombosis.
(1)Report untoward reactions to physician.
(2)Apply warm compresses to ease discomfort, as ordered.
- If topical anesthetic is used during procedure
(e.g., gastroscopy, bronchoscopy), do not give food or fluid until gag reflex returns.
- Encourage relaxation by allowing client to discuss experience and verbalize feelings.
B. Procedures to evaluate the cardiovascular system:
1. Angiocardiography—intravenous injection of a radiopaque solution or contrast medium for the purpose of studying its circulation through the client’s heart, lungs, and great vessels; used to: check the competency of heart valves, diagnose congenital septal defects, detect occlusions of coronary arteries, confirm suspected diagnoses,
and study heart function and structure before cardiac surgery.
2. Cardiac catheterization—insertion of a radiopaque catheter into a vein to study the heart and great vessels.
- Right-heart catheterization—catheter is inserted through a cut down in the antecubital vein into the superior vena cava, through the right atrium and ventricle, and into the pulmonary artery.
- Left-heart catheterization—catheter may be passed retrograde to the left ventricle through the brachial or femoral artery; it can be passed into the left atrium after right-heart catheterization by means of a special needle that punctures the septa; or it may be passed directly into the left ventricle by means of a posterior or anterior chest puncture.
- Cardiac catheterizations are used to:
(1) Confirm diagnosis of heart disease and determine the extent of disease.
(2)Determine existence and extent of congenital abnormalities.
(3)Measure pressures in the heart chambers and great vessels.
(4)Obtain estimate of cardiac output.
(5)Obtain blood samples to measure oxygen content and determine presence of cardiac shunts.
d. Specific nursing interventions:
(1)Pre-procedure client teaching:
(a) Fatigue due to lying still for 3 hours or more is a common complaint.
(b)Some fluttery sensations may be felt— occur as catheter is passed backward into the left ventricle.
(c) Flushed, warm feeling may occur when contrast medium is injected.
(2) Postprocedure observations:
(a)Monitor ECG pattern for arrhythmias.
(b) Check extremities for color and temperature, peripheral pulses (femoral and dorsalis pedis) for quality.
3. Angiography (arteriography)—injection of a contrast medium into the arteries to study the vascular tree; used to: determine obstructions or narrowing of peripheral arteries.
4. Pericardiocentesis (pericardial aspiration)— puncture of the pericardial sac is performed to remove fluid accumulating with pericardial effusion. The goal is to prevent cardiac tamponade (compression of the heart).
Nursing interventions: monitor ECG and central venous pressure (CVP) during the procedure, have resuscitative equipment ready. Head of bed elevated to 45 to 60 degrees. Maintain peripheral IV with saline or glucose. Following the procedure: monitor BP, CVP, and heart sounds for recurrence of tamponade (pulsus paradoxus).
C. Procedures to evaluate the respiratory system:
1. Pulmonary circulation studies—used to: determine regional distribution of pulmonary blood flow.
- Lung scan—injection of radioactive isotope into the body, followed by lung scintiscan, which produces a graphic record of gamma rays emitted by the isotope in lung tissues; used to: determine lung perfusion when space occupying
lesions or pulmonary emboli and infarction are suspected.
- Pulmonary angiography—x-ray visualization of the pulmonary vasculature after the injection of a radiopaque contrast medium; used to: evaluate pulmonary disorders (e.g., pulmonary embolism, lung tumors, aneurysms, and changes in the pulmonary vasculature due to such conditions as emphysema or congenital defects).
2. Bronchoscopy—introduction of a special lighted instrument (bronchoscope) into the trachea and bronchi; used to: inspect tracheobronchial tree for pathological changes, remove tissue for cytological and bacteriological studies, remove foreign bodies or mucous plugs causing airway obstruction, assess functional residual capacity of diseased lung, and apply chemotherapeutic agents.
a. Prebronchoscopy nursing interventions:
- Oral hygiene.
- Postural drainage is indicated.
b. Postbronchoscopy nursing interventions:
- Instruct client not to swallow oral secretions but to let saliva run from side
- Save expectorated sputum for laboratory analysis, and observe for frank bleeding.
- NPO until gag reflex returns.
- Observe for subcutaneous emphysema and dyspnea.
- Apply ice collar to reduce throat discomfort.
3. Thoracentesis—needle puncture through the chest wall and into the pleura; used to: remove fluid and occasionally air from the pleural space.
a.Nursing interventions before thoracentesis:
- Position: high-Fowler’s position or sitting up on edge of bed, with feet supported on chair to facilitate accumulation of fluid in the base of the chest.
- If client is unable to sit up—turn onto unaffected side.
- Evaluate continually for signs of shock, pain, cyanosis, increased respiratory rate, and pallor.
D. Procedures to evaluate the renal system:
1. Renal angiogram—small catheter is inserted into the femoral artery and passed into the aorta or renal artery, radiopaque fluid is instilled, and serial films are taken.
- Used to: diagnose renal hypertension and pheochromocytoma and differentiate renal cysts from renal tumors.
- Postangiogram nursing actions: check pedal pulse for signs of decreased circulation.
2. Cystoscopy—visualization of bladder, urethra, and prostatic urethra by insertion of a tubular, lighted, telescopic lens (cystoscope) through the urinary meatus.
- Used to: directly inspect the bladder; collect urine from the renal pelvis; obtain biopsy specimens from bladder and urethra; remove calculi; and treat lesions in the bladder, urethra, and prostate.
- Nursing interventions following procedure:
(1)Observe for urinary retention.
(2)Warm sitz baths to relieve discomfort.
3. Renal biopsy—needle aspiration of tissue from the kidney for the purpose of microscopic examination.
E. Procedures to evaluate the digestive system:
- Celiac angiography, hepatoportography, and umbilical venography—injection of a contrast medium into the portal vein or related vessel; used to: determine patency of vessels supplying target organ or detect lesions in the organs that distort the vasculature.
- Esophagoscopy and gastroscopy—visualization of the esophagus, the stomach, and sometimes the duodenum by means of a lighted tube inserted through the mouth.
- Proctoscopy—visualization of rectum and colon by means of a lighted tube inserted through the anus.
- Peritoneoscopy—direct visualization of the liver and peritoneum by means of a peritoneoscope inserted through an abdominal stab wound.
- Liver biopsy—needle aspiration of tissue for the purpose of microscopic examination; used to: determine tissue changes, facilitate diagnosis, and provide information regarding a disease course.
Nursing interventions: place client on right side and position pillow for pressure, to prevent bleeding.
- Paracentesis—needle aspiration of fluid from the peritoneal cavity; used to: relieve excess fluid accumulation or for diagnostic studies.
a. Specific nursing interventions before paracentesis:
(1)Have client void—to prevent possible injury to bladder during procedure.
(2) Position—sitting up on side of bed, with feet supported by chair.
(3)Check vital signs and peripheral circulation frequently throughout procedure.
(4)Observe for signs of hypovolemic shock— may occur due to fluid shift from vascular compartment following removal of protein-rich ascitic fluid.
b. Specific nursing interventions following paracentesis:
(1)Apply pressure to injection site and cover with sterile dressing.
(2)Measure and record amount and color of ascitic fluid; send specimens to laboratory for diagnostic studies.
- Small-bowel biopsy—a specimen is obtained by passing a tube through the oral cavity and is microscopically examined for changes in cellular morphology.
Nursing interventions: no food or fluids 8 hours before procedure. Obtain written consent. Remove dentures if present. Monitor vital signs before, during, and after procedure for indications of hemorrhage. Procedure takes approximately 1 hour.
F. Procedures to evaluate the reproductive system in women:
- Culdoscopy—surgical procedure in which a culdoscope is inserted into the posterior vaginal cul-de-sac; used to: visualize uterus, fallopian tubes, broad ligaments, and peritoneal contents.
- Hysterosalpingography—x-ray examination of uterus and fallopian tubes following insertion of a radiopaque substance into the uterine cavity; used to: determine patency of fallopian tubes and detect pathology in uterine cavity.
- Breast biopsy—needle aspiration or incisional removal of breast tissue for microscopic examination; used to: differentiate among benign tumors,
cysts, and malignant tumors in the breast.
- Cervical biopsy and cauterization—removal of cervical tissue for microscopic examination and cautery; used to: control bleeding or obtain additional tissue samples.
- Uterotubal insufflation (Rubin’s test)—injection of carbon dioxide into the cervical canal; used to: determine fallopian tube patency.
G. Procedures to evaluate the neuroendocrine system:
1. Radioactive iodine uptake test (iodine-131 [131I] uptake)—ingestion of a tracer dose of 131I, followed in 24 hours by a scan of the thyroid for amount of radioactivity emitted.
- High uptake indicates hyperthyroidism.
- Low uptake indicates hypothyroidism.
2. Eight-hour intravenous ACTH test—administration of 25 units of adrenocorticotropic hormone (ACTH) in 500 mL of saline over an 8-hour period.
- Used to: determine function of adrenal cortex.
- 24-hour urine specimens are collected, before and after administration, for measurement of 17-ketosteroids and 17-hydroxycorticosteroids.
- In Addison’s disease, urinary output of steroids does not increase following administration of ACTH; normally steroid excretion increases threefold to fivefold following ACTH stimulation.
- In Cushing’s syndrome, hyperactivity of the adrenal cortex increases the urine output of steroids in the second urine specimen 10-fold.
3. Cerebral angiography—fluoroscopic visualization of the brain vasculature after injection of a contrast medium into the carotid or vertebral arteries; used to: localize lesions (tumors, abscesses, intracranial hemorrhages, and occlusions) that are large enough to distort cerebrovascular blood flow.
4. Myelogram—through a lumbar puncture needle, a contrast medium is injected into the subarachnoid space of the spinal column to visualize the spinal cord; used to: detect herniated or ruptured intervertebral disks, tumors, or cysts that compress or distort spinal cord.
Nursing interventions: elevate head of bed with water-soluble contrast; flat with oil contrast; check for bladder distention with metrizamide (water soluble); vital signs every 4 hours for 24 hours.
5. Brain scan—intravenous injection of a radioactive substance, followed by a scan for emission of radioactivity.
- Increased radioactivity at site of abnormality.
- Used to: detect brain tumors, abscesses, hematomas, and arteriovenous malformations.
6. Lumbar puncture—puncture of the lumbar subarachnoid space of the spinal cord with a needle to withdraw samples of cerebrospinal fluid (CSF); used to: evaluate CSF for infections and determine presence of hemorrhage. Not done if increased intracranial pressure (ICP) suspected.
H. Procedures to evaluate the skeletal system.
Arthroscopy—examination of a joint through a fiberoptic endoscope called an arthroscope. Usually done in the operating room (same-day surgery) under aseptic conditions using a local anesthetic, although a general anesthetic may be used. A tourniquet is used to reduce blood flow to the area while the scope is introduced through a cannula. Saline is used as the viewing medium. Biopsy or removal of loose
bodies from the joint may be done. A compression dressing (e.g., Ace bandage) is applied. Restrictions vary according to surgeon preference and nature of procedure. Weight-bearing may be immediate or restricted for 24 hours. Teach client to observe for signs of infection.