Area of applicationPulmonary vasculature.
ContrastIntravenous iodine based.
This procedure is contraindicated for
- Patients 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 and mother.
- 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 (shellfish contain high levels of iodine), it has been well established that the reaction is not to iodine; 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.
- Conditions associated with preexisting renal insufficiency (e.g., renal failure, single kidney transplant, nephrectomy, diabetes, multiple myeloma, treatment with aminoglycocides and NSAIDs) because iodinated contrast is nephrotoxic.
- Elderly and compromised patients who are chronically dehydrated before the test because of their risk of contrast-induced renal failure.
- Patients with pheochromocytoma because iodinated contrast may cause a hypertensive crisis.
- Patients with bleeding disorders or receiving anticoagulant therapy because the puncture site may not stop bleeding.
- Detect acute pulmonary embolism
- Detect arteriovenous malformations or aneurysms
- Detect tumors; aneurysms; congenital defects; vascular changes associated with emphysema, blebs, and bullae; and heart abnormalities
- Determine the cause of recurrent or severe hemoptysis
- Evaluate pulmonary circulation
- Normal pulmonary vasculature; radiopaque iodine contrast medium should circulate symmetrically and without interruption through the pulmonary circulatory system.
Abnormal findings related to
- Arterial hypoplasia or stenosis
- Arteriovenous malformations
- Bleeding caused by tuberculosis, bronchiectasis, sarcoidosis, or aspergilloma
- Inflammatory diseases
- Pulmonary embolism (PE) acute or chronic (visualized as an area of interrupted opacity in the pulmonary artery)
- Pulmonary sequestration
It is essential that critical findings be communicated immediately to the requesting health-care provider (HCP). A listing of these findings varies among facilities.
Timely notification of a critical finding for lab or diagnostic studies is a role expectation of the professional nurse. The notification processes will vary among facilities. Upon receipt of the critical finding the information should be read back to the caller to verify accuracy. Most policies require immediate notification of the primary HCP, hospitalist, or on-call HCP. Reported information includes the patient’s name, unique identifiers, critical finding, name of the person giving the report, and name of the person receiving the report. Documentation of notification should be made in the medical record with the name of the HCP notified, time and date of notification, and any orders received. Any delay in a timely report of a critical finding may require completion of a notification form with review by Risk Management.
Factors that may impair clear imaging
- Retained barium from a previous radiological procedure.
- Metallic objects within the examination field (e.g., jewelry, body rings), which may inhibit organ visualization and can produce unclear images.
- Inability of the patient to cooperate or remain still during the procedure because of age, significant pain, or mental status.
- Consultation with an 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.
- Failure to follow dietary restrictions and other pretesting preparations may cause the procedure to be canceled or repeated.
Nursing Implications and Procedure
- 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 with assessment of lung function and check for disease.
- 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 the patient’s cardiovascular and respiratory systems, symptoms, and results of previously performed laboratory tests and diagnostic and surgical procedures. Ensure results of coagulation testing are obtained and recorded prior to the procedure; a creatinine level is also needed before contrast medium is to be used.
- Note any recent procedures that can interfere with test results, including examinations using iodine-based contrast medium or barium. Ensure that barium studies were performed more than 4 days before angiography.
- 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, especially those known to affect coagulation (see Effects of Natural Products on Laboratory Values online at DavisPlus). Such products should be discontinued by medical direction for the appropriate number of days prior to a surgical procedure. Note the last time and dose of medication taken.
- 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 a radiology or vascular suite by an HCP and takes approximately 30 to 60 min.
- Sensitivity to social and cultural issues, as well as concern for modesty, is important in providing psychological support before, during, and after the procedure.
- Explain that an IV line may be inserted to allow infusion of IV fluids such as normal saline, anesthetics, sedatives, or emergency medications. Explain that the contrast medium will be injected, by catheter, at a separate site from the IV line.
- Inform the patient that a burning and flushing sensation may be felt throughout the body during injection of the contrast medium. After injection of the contrast medium, the patient may experience an urge to cough, flushing, nausea, or a salty or metallic taste.
- Instruct the patient to remove jewelry and other metallic objects from the area to be examined.
- Instruct the patient to fast and restrict fluids for 2 to 4 hr prior to the procedure. Protocols may vary among facilities.
- This procedure may be terminated if chest pain, severe cardiac arrhythmias, or signs of a cerebrovascular accident occur.
- Make sure a written and informed consent has been signed prior to the procedure and before administering any medications.
- Potential complications:
Injection of the contrast by inserting a catheter into a blood vessel is an invasive procedure. Complications are rare but do include risk for: allergic reaction (related to contrast reaction); bleeding (related to perforation of the blood vessel—postprocedural bleeding from the site is rare because at the conclusion of the procedure a resorbable device, composed of non-latex-containing arterial anchor, collagen plug, and suture, is deployed to seal the puncture site); blood clot formation (related to thrombus formation on the tip of the catheter sheath surface or in the lumen of the catheter—the use of a heparinized saline flush during the procedure decreases the risk of emboli); hematoma (related to blood leakage into the tissue following insertion of the catheter); infection (which might occur if bacteria from the skin surface is introduced during catheter insertion); tissue damage (related to extravasation of the contrast during injection); or nerve injury or damage to a nearby organ (which might occur if the catheter strikes a nerve or perforates an organ).
- Observe standard precautions, and follow the general guidelines in Patient Preparation and Specimen Collection. Positively identify the patient.
- Ensure the patient has complied with dietary, fluid, and medication restrictions and pretesting preparations for 2 to 4 hr prior to the procedure.
- Ensure the patient has removed all external metallic objects from the area to be examined.
- Administer ordered prophylactic steroids or antihistamines before the procedure. Use nonionic contrast medium for 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.
- Instruct the patient to cooperate fully and to follow directions. Instruct the patient to remain still throughout the procedure because movement produces unreliable results.
- Record baseline vital signs, and continue to monitor throughout the procedure. Protocols may vary among facilities.
- Establish an IV fluid line for the injection of saline, sedatives, or emergency medications.
- Administer an antianxiety agent, as ordered, if the patient has claustrophobia. Administer a sedative to a child or to an uncooperative adult, as ordered.
- Place electrocardiographic electrodes on the patient for cardiac monitoring. Establish a baseline rhythm; determine if the patient has ventricular arrhythmias.
- Using a pen, mark the site of the patient’s peripheral pulses before angiography; this allows for quicker and more consistent assessment of the pulses after the procedure.
- Place the patient in the supine position on an examination table. Cleanse the selected area, and cover with a sterile drape.
- A local anesthetic is injected at the site, and a small incision is made or a needle is inserted under fluoroscopy.
- The contrast medium is injected, and a rapid series of images is taken during and after the filling of the vessels to be examined.
- Instruct the patient to inhale deeply and hold his or her breath while the images are taken, and then to exhale after the images are taken.
- Instruct the patient to take slow, deep breaths if nausea occurs during the procedure.
- Monitor the patient for complications related to the procedure (e.g., allergic reaction, anaphylaxis, bronchospasm).
- The needle or catheter is removed, and a pressure dressing is applied over the puncture site.
- Observe/assess the needle/catheter insertion site for bleeding, inflammation, or hematoma formation.
- 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, fluids, medications, or activity, as directed by the HCP. Renal function should be assessed before metformin is resumed.
- Monitor vital signs and neurological status every 15 min for 1 hr, then every 2 hr for 4 hr, and as ordered. Take the temperature every 4 hr for 24 hr. Monitor intake and output at least every 8 hr. Compare with baseline values. Protocols may vary from facility to facility.
- Observe for delayed allergic reactions, such as 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.
- Assess extremities for signs of ischemia or absence of distal pulse caused by a catheter-induced thrombus.
- Observe/assess the needle/catheter insertion site for bleeding, inflammation, or hematoma formation.
- Instruct the patient in the care and assessment of the site.
- Instruct the patient to apply cold compresses to the puncture site as needed, to reduce discomfort or edema.
- Instruct the patient to maintain bedrest for 4 to 6 hr after the procedure or as ordered.
- Recognize anxiety related to test results, and be supportive of perceived loss of independent function. 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 performed 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 tests include alveolar/arterial gradient, blood gases, BNP, BUN, chest x-ray, creatinine, CT angiography, CT thoracic, ECG, FDP, lactic acid, lung perfusion scan, lung ventilation scan, MRA, MRI chest, MRI venography, aPTT, and PT/INR.
- Refer to the Cardiovascular and Respiratory systems tables at the end of the book for related tests by body system.