Contrast Media Flashcards
What is contrast media?
A substance introduced into the body that is radiopaque and is used to outline organs and structures within the body
What types of contrast agents should be used for upper and lower GI exams?
Positive and Negative contrast
What are positive contrast?
Barium or Gastrografin
What are negative contrasts?
Air
If the patient is suspected to have a perforation of the bowel what contrast should be used?
Gastrographin
What does a BE series include?
Fluoroscopy and several radiographs taken before, during and after the introduction of contrast material
What are the types of enemas?
NAME?
What are basic BE instructions given to patients before the exam?
NAME?
What foods are included in a low residue diet?
No milk, meat, eggs, fruit or vegetables
What is purgatation?
When the patient is prescribed laxatives to promote emptying of the colon
What is over hydration when it comes to BE prep?
Patients are instructed to follow a clear liquid diet 24 hours prior to the exam
How are cleansing enema a part of BE prep?
As many as 3 cleansing enema should be done the morning of the exam
How is the barium solution prepared?
Contrast media is mixed with water that’s 105 degrees
If cramping occurs while the BE is introduced what should be done?
Tell the patient to inhale and exhale slowly and deeply and to try to relax
How does barium or gastrographin look on an image?
The same, white
What is viscosity?
They physical property of liquids and how thick they are
What are double contrast barium enemas used for?
Detection of polyps, history of colorectal cancer or rectal bleeding
What two contrasts are used in double contrast BE’s?
Solution barium and air/carbon dioxide
What is air used for in a double contrast BE?
To expand the colon
What are important patient concerns with a BE?
- keep the tip firmly in the rectum
- relax abdominal muscles to reduce pressure
- use deep breathing to prevent spasm and cramps
- try to take the patient’s attention away from the enema
What procedures should patient’s take post BE?
Increase fluid intake and dietary fiber
What is a UGI?
Upper Gi series that includes visualizing the terminal esophagus, stomach and proximal small intestine
What does an Upper GI Series include?
Fluoroscopy and a series of radiographs taken before during and after the introduction of contrast material
What is an esophagram?
Imaging where only the esophagus is visualized
How are images taken for an esophagram?
Taken while the patient swallows the contrast mixture
What is a small bowel series?
When the small intestine is visualized
How is the barium and imaging done for a small bowel series?
Patient drinks two full GI cups of barium and radiographs are taken in intervals every 1/2 hour until barium reaches the ileocecal of the large intestine
What is a Gallbladder series?
Radiograph of the gallbladder
What is the patient prep for a GI series?
Iodinated contrast tablets are given to the patient the night before and on the day of a series of radiographs are taken
What is Intravenous pyelogram?
A radiographic procedure in which contrast material is injected into the vein a travels to the kidneys
How is the radiograph complete for an IVP?
Taken at certain time intervals showing the contrast in the kidneys, ureters, bladder and urethra
What type of contrast is used for IVP?
Renographin which is a water-soluble iodine compound
What is post-voiding film?
A radiograph taken after the patient has urinated to demonstrate the contrast is gone
What is the sequence for contrast exams?
- IVP
- GB
- BE
- GI
What does the sequence of contrast exams depend on?
How quickly the contrast can be eliminated from the body
What are contrast exams that be performed together?
GB and IVP
IVP and BE
GB and GI
What is the patient prep for IVP?
NAME?
What is the patient prep for GB?
NAME?
What is the patient prep for BE?
NAME?
What is the patient prep for UGI?
NPO after midnight
If a patient is instructed to be NPO they may not have any food, water, liquids or smoke.
What are specialty contrast agents?
those agents used for specialty exams such as MRI and Sonography
What are complications of negative contrasts?
Embolus (air injected into the bloodstream)
Because of the risk of air emboli, negative contrast media is never introduced (injected) into the bloodstream.
Joint distention, pain will occur after the injection of air into the joint space
What are negative contrast agents?
Air and Carbon dioxide
May be used by themselves or combined with a positive contrast
What are positive contrast agents?
Barium sulfate, BaSO4
Iodinated preparations
Oil-based
Water-soluble
What are complications of Barium?
Barium may pass into the peritoneal cavity or bloodstream through a break in the mucosa.
Barium is contraindicated if there is a question of a perforation of the digestive tract.
Barium cannot be absorbed into the body.
Peritonitis may occur if barium enters the pelvic or peritoneal cavity. The barium will need to be surgically removed.
In place of barium a water soluble iodine contrast will be used such as Gastrographin.
Barium Peritonitis is an extravasation of BaSO4 into the abdominal cavity.
Constipation – patients should be instructed to drink plenty of water for a few days following an exam in which BASO4 is used. The main symptom of obstruction of the colon is constipation.
What are features of iodinated contrast agents?
Oil Based
Insoluble in water.
High viscosity – oil based iodinated contrasts do not flow easily through the syringe.
Oil based contrast agents are used infrequently in radiography.
Oil based contrasts are used for i.e. Bronchography and Lymphography.
Store in a cool, dark area. When exposed in air, heat and light the contrast breaks down or decomposes.
When shouldn’t you use iodinated contrast agents?
Do not use it if color change occurs.
The color of oil based contrast agents should be a pale yellow or amber.
A dark color change indicates a decomposition of the contrast material.
What types of syringes should be used for iodinated contrast agents?
Use only glass syringes, not plastic.
Toxic substances from plastic syringes may dissolve into the Oil based contrast.
What are the most commonly used iodinated contrast agents?
Water-Soluble Iodine Contrast Agents
When should non iodinated contrast agents be used?
Hx of adverse reactions to contrast
Hx of asthma or allergies
Known cardiac problems
Diabetes mellitus
Renal disease
Sickle cell disease
Elevated creatine levels
Patients that will have a Helical CT
What are examples of non-iodinated contrast agents?
Isovue
Omnipaque
Ultravist
What are minor reactions to contrast media?
Not life threatening and do not normally require medical treatment.
Rash, Hives (urticaria)
Vomiting, Nausea
Cough
Itchy palms and soles of the feet
Metallic or altered taste
Warmth, heat
Headache
Dizziness
Shaking
Pallor
Flushing of the skin
Chills, sweats
Nasal stuffiness
Swelling, eyes and face
Anxiety
What is the radiographer’s response to minor reactions?
First notify the radiology nurse, radiology or MD of any reactions that the patient is having from the contrast agent. If the signs of the allergic reaction are not severe and are not progressing, then the patient should be carefully watched and reassured that everything is OK. No treatment is usually required.
What are vasovagal reactions?
a sudden episode of hypotension and fainting that may occur during a radiographic procedure induced by the response of the nervous system to abrupt emotional stress, pain, or trauma.
The Vasovagal nerve becomes over stimulated and the patient may become extremely lightheaded and may pass out. The Vasovagal reaction is also called a Vasovagal attack.
What is the radiographer’s response to vasovagal reactions?
Check the person’s airway, breathing and circulation.
If necessary, call a code and begin rescue breathing and CPR.
Loosen tight clothing around the neck.
Keep the affected person lying down for at least 10-15 minutes, preferably in a cool and quiet space.
If the person cannot lie down, have him sit forward and lower his head below the levels of the shoulders, between the knees.
If the person has vomited, turn him or her to one side to prevent choking and aspiration.
Elevate the feet above the level of the heart (about 12 inches).
What are moderate reactions to contrast media?
Transitory episodes that require the patient to be watched closely.
Respiratory
Tachycardia/Bradycardia
Hypotension
Hypertension
Persistent hives – pronounced cutaneous reactions
Facial swelling
Dyspnea
Bronchospasm, wheezing
Laryngeal edema
What is the radiographer’s response to moderate reactions?
First notify the radiology nurse, radiologist or MD of any reactions that the patient is having from the contrast agent. Clinical findings will indicate the need for immediate medical treatment including drug therapy.
What are severe reactions to contrast media?
Those that endanger life and require immediate medical attention.
Convulsions
Laryngeal edema
Severe respiratory symptoms
Severe hypotension
Cardiac arrhythmia
Shock
Unconsciousness, unresponsiveness
Cardiopulmonary Arrest
What is the radiographer’s response to severe reactions?
Immediately obtain medical assistance. Inform the radiologist or MD of any reactions that the patient is having from the contrast agent.
Clinical findings will indicate the need for immediate medical treatment including drug therapy.
What blood tests should be done before contrast exams to determin renal function?
BUN and Creatine
What is BUN?
Blood urea notrogen
What does BUN results provide?
BUN provides information about kidney function and the ability of the kidneys to remove impurities from the body.
BUN normal values range between 5 to 25 mg/dl.
What is creatine?
creatine is a waste product stored in the muscles.
What do creatine results provide?
Elevated creatine levels indicate impairment of the function of the kidneys.
Creatine normal values range between 0.6 to 1.7 mg/dl
