voiding cystourethrogram

Cystourethrography, Voiding

Common use

Area of application

Contrast

Description

This procedure is contraindicated for

• high alertPatients who are pregnant or suspected of being pregnant, unless the potential benefits of a procedure using radiation far outweigh the risk of radiation exposure to the fetus.
• high alertPatients with conditions associated with adverse reactions to contrast medium (e.g., asthma, food allergies, or allergy to contrast medium). Although patients are still asked specifically if they have a known allergy to iodine or shellfish, it has been well established that the reaction is not to iodine, in fact an actual iodine allergy would be very problematic because iodine is required for the production of thyroid hormones. In the case of shellfish, the reaction is to a muscle protein called tropomyosin; in the case of iodinated contrast medium, the reaction is to the noniodinated part of the contrast molecule. Patients with a known hypersensitivity to the medium may benefit from premedication with corticosteroids and diphenhydramine; the use of nonionic contrast or an alternative noncontrast imaging study, if available, may be considered for patients who have severe asthma or who have experienced moderate to severe reactions to ionic contrast medium.
• high alertPatients with conditions associated with preexisting renal insufficiency (e.g., renal failure, single kidney transplant, nephrectomy, diabetes, multiple myeloma, treatment with aminoglycosides and NSAIDs) because iodinated contrast is nephrotoxic.
• high alertElderly and compromised patients who are chronically dehydrated before the test, because of their risk of contrast-induced renal failure.
• high alertPatients with bleeding disorders because the puncture site may not stop bleeding.
• high alertPatients with an active urinary tract infection, obstruction, or injury.

Indications

• Assess the degree of compromise of a stenotic prostatic urethra
• Assess hypertrophy of the prostate lobes
• Assess ureteral stricture
• Confirm the diagnosis of congenital lower urinary tract anomaly
• Evaluate abnormal bladder emptying and incontinence
• Evaluate the effects of bladder trauma
• Evaluate possible cause of frequent UTIs
• Evaluate the presence and extent of ureteral reflux
• Evaluate the urethra for obstruction and strictures

Potential diagnosis

Normal findings

• Normal bladder and urethra structure and function

Abnormal findings related to

• Bladder trauma
• Bladder tumors
• Hematomas
• Neurogenic bladder
• Pelvic tumors
• Prostatic enlargement
• Ureteral stricture
• Ureterocele
• Urethral diverticula
• Vesicoureteral reflux

Critical findings

N/A

Interfering factors

• Factors that may impair clear imaging

  • Metallic objects within the examination field, which may inhibit organ visualization and cause unclear images.
  • Inability of the patient to cooperate or remain still during the procedure because of age, significant pain, or mental status.
  • Gas or feces in the gastrointestinal tract resulting from inadequate cleansing or failure to restrict food intake before the study.
  • Retained barium from a previous radiological procedure.

• Other considerations

  • Consultation with a health-care provider (HCP) should occur before the procedure for radiation safety concerns regarding younger patients or patients who are lactating. Pediatric & Geriatric Imaging Children and geriatric patients are at risk for receiving a higher radiation dose than necessary if settings are not adjusted for their small size. Pediatric Imaging Information on the Image Gently Campaign can be found at the Alliance for Radiation Safety in Pediatric Imaging (www.pedrad.org/associations/5364/ig/).
  • Risks associated with radiation overexposure can result from frequent x-ray procedures. Personnel in the room with the patient should wear a protective lead apron, stand behind a shield, or leave the area while the examination is being done. Personnel working in the examination area should wear badges to record their level of radiation exposure.

Nursing Implications and Procedure

Pretest

• Positively identify the patient using at least two unique identifiers before providing care, treatment, or services.
• Patient Teaching: Inform the patient this procedure can assist in assessing the urinary tract.
• Obtain a history of the patient’s complaints or clinical symptoms, including a list of known allergens, especially allergies or sensitivities to latex, anesthetics, contrast medium, or sedatives.
• Obtain a history of results of the patient’s genitourinary system, symptoms, and previously performed laboratory tests and diagnostic and surgical procedures. Ensure that the results of blood tests are obtained and recorded before the procedure, especially coagulation tests, BUN, and creatinine if contrast medium is to be used.
• Ensure that this procedure is performed before an upper gastrointestinal study or barium swallow.
• Record the date of the last menstrual period and determine the possibility of pregnancy in perimenopausal women.
• Obtain a list of the patient’s current medications, including anticoagulants, aspirin and other salicylates, herbs, nutritional supplements, and nutraceuticals (see Effects of Natural Products on Laboratory Values online at DavisPlus). Note the last time and dose of medication taken.
• Note that if iodinated contrast medium is scheduled to be used in patients receiving metformin (Glucophage) for non-insulin-dependent (type 2) diabetes, the drug should be discontinued on the day of the test and continue to be withheld for 48 hr after the test. Iodinated contrast can temporarily impair kidney function, and failure to withhold metformin may indirectly result in drug-induced lactic acidosis, a dangerous and sometimes fatal side effect of metformin related to renal impairment that does not support sufficient excretion of metformin.
• Review the procedure with the patient. Address concerns about pain and explain that there may be moments of discomfort and some pain experienced during the test. Inform the patient that the procedure is usually performed in the radiology department by an HCP, with support staff, and takes approximately 30 to 60 min. Pediatric Considerations There is no specific pediatric patient preparation for cystourethrography. Encourage parents to be truthful about unpleasant sensations (pinching or pushing) the child may experience during catheter insertion and to use words that they know their child will understand. Toddlers and preschool-age children have a very short attention span, so the best time to talk about the test is right before the procedure. The child should be assured that he or she will be allowed to bring a favorite comfort item into the examination room, and if appropriate, that a parent will be with the child during the procedure. Infants and small children may be wrapped tightly in a blanket to assist in keeping them still during the procedure.
• Sensitivity to social and cultural issues, as well as concern for modesty, is important in providing psychological support before, during, and after the procedure.
• Inform the patient that he or she may receive a laxative the night before the test or an enema or a cathartic the morning of the test, as ordered.
• Instruct the patient to increase fluid intake the day before the test and to have only clear fluids 8 hr before the test.
• Make sure a written and informed consent has been signed prior to the procedure and before administering any medications.

Intratest

• Potential complications:

• Complications include dysuria, injury to the urethra, and urinary infection related to use of a catheter. Allergic reaction to contrast media is another potential complication.

• Observe standard precautions, and follow the general guidelines in Patient Preparation and Specimen Collection. Positively identify the patient.
• Ensure that the patient has complied with dietary restrictions. Assess for completion of bowel preparation if ordered.
• Ensure that the patient has removed all external metallic objects from the area to be examined prior to the procedure.
• Administer ordered prophylactic steroids or antihistamines before the procedure if the patient has a history of allergic reactions to any substance or drug.
• Avoid the use of equipment containing latex if the patient has a history of allergic reaction to latex.
• Have emergency equipment readily available.
• Instruct the patient to void prior to the procedure and to change into the gown, robe, and foot coverings provided.
• Insert a Foley catheter before the procedure, if ordered. Inform the patient that he or she may feel some pressure when the catheter is inserted and when the contrast medium is instilled through the catheter.
• Place the patient on the table in a supine or lithotomy position.
• A kidney, ureter, and bladder radiograph (KUB) is taken to ensure that no barium or stool obscures visualization of the urinary system.
• A catheter is filled with contrast medium to eliminate air pockets and is inserted until the balloon reaches the meatus if not previously inserted in the patient.
• When three-fourths of the contrast medium has been injected, a radiographic exposure is made while the remainder of the contrast medium is injected.
• When the patient is able to void, the catheter is removed and the patient is asked to urinate while images of the bladder and urethra are recorded.
• Monitor the patient for complications related to the procedure (e.g., allergic reaction, anaphylaxis, bronchospasm).

Post-Test

• Inform the patient that a report of the results will be made available to the requesting HCP, who will discuss the results with the patient.
• Instruct the patient to resume usual diet and medications, as directed by the HCP.
• Monitor vital signs and neurological status every 15 min for 1 hr, then every 2 hr for 4 hr, and then as ordered by the HCP. Take the temperature every 4 hr for 24 hr. Monitor intake and output at least every 8 hr. Compare with baseline values. Notify the HCP if temperature is elevated. Protocols may vary among facilities.
• Monitor for reaction to iodinated contrast medium, including rash, urticaria, tachycardia, hyperpnea, hypertension, palpitations, nausea, or vomiting.
• Instruct the patient to immediately report symptoms such as fast heart rate, difficulty breathing, skin rash, itching, chest pain, persistent right shoulder pain, or abdominal pain. Immediately report symptoms to the appropriate HCP.
• Maintain the patient on adequate hydration after the procedure. Encourage the patient to drink increased amounts of fluids (125 mL/hr for 24 hr) after the procedure to prevent stasis and bacterial buildup.
• Recognize anxiety related to test results. Discuss the implications of abnormal test results on the patient’s lifestyle. Provide teaching and information regarding the clinical implications of the test results, as appropriate.
• Reinforce information given by the patient’s HCP regarding further testing, treatment, or referral to another HCP. Answer any questions or address any concerns voiced by the patient or family.
• Depending on the results of this procedure, additional testing may be needed to evaluate or monitor progression of the disease process and determine the need for a change in therapy. Evaluate test results in relation to the patient’s symptoms and other tests performed.

Related Monographs

• Related tests include biopsy prostate, bladder cancer markers, BUN, CT pelvis, creatinine cytology urine, IVP, MRI pelvis, PSA, PT/INR, and US pelvis.
• Refer to the Genitourinary System table at the end of the book for related tests by body system.