DRUG CLASSIFICATIONS, CHEMISTRY, & PHARMACOLOGY OF CONTRAST AGENTS

Question 1

These are high-density pharmacologic agents used to visualize low-contrast tissues in the body, such as the vasculature, kidneys, gastrointestinal (GI) tract, and biliary tree.

Answer 1

RADIOPAQUE CONTRAST AGENTS
(ROCM)

Question 2

MOST FREQUENTLY PRESCRIBED ROCM

Answer 2

Iodine
barium

Question 3

atomic number 53

Answer 3

IODINE

Question 4

atomic number 56

Answer 4

BARIUM

Question 5

MOST FREQUENTLY PRESCRIBED ROCM

Answer 5

LOW-KILOVOLTAGE (below 80 kVp)
HIGHER KILOVOLTAGE (above 90 kVp)

Question 6

usually selected to produce high-contrast radiographs of the blood vessels or genitourinary tract.

Answer 6

LOW-KILOVOLTAGE (below 80 kVp)

Question 7

used in GI examinations not only to reveal the presence of the organ, but also to penetrate the contrast media to see the walls and inner structures.

Answer 7

HIGHER KILOVOLTAGE (above 90 kVp)

Question 8

are available in parenteral and enteral, ionic and nonionic, and high-osmolality and low-osmolality forms. With the exception of barium, used for roentgenography are derivatives of triiodinated benzoic acid

Answer 8

ROCM

Question 9

It is the movement of water across semipermeable membrane.

Answer 9

OSMOSIS

Question 10

It controls the distribution and movement of water between body compartments. It is also the number of milliosmoles per kilogram of water (mOsm/kg), or the concentration of molecules per weight of water.

Answer 10

OSMOLALITY

Question 11

It is the number of milliosmoles per liter of solution (mOsm/L), or the concentration of molecules per volume of solution.

Sometimes the difference between the two measurements is insignificant.

Answer 11

OSMOLARITY

Question 12

Used to add density to vascular structures. Increased density of the media alters the attenuation of x-rays passing through the area, thus enhancing the anatomic image on the radiographic film.

Answer 12

INTRAVASCULAR RADIOPAQUE CM

Question 13

Diagnostic effects of intravascular radiopaque contrast media (ROCM) are a function of the iodine contained within them. Adverse effects elicited by ROCM depend at least partially on their serum or tissue iodine concentration and osmolality and their calcium-chelating, anticoagulant, and immune system-stimulating abilities.

Answer 13

IODINATED RADIOPAQUE CM

Question 14

Must be within the range of 280 to 370 mg/ml for a normal x-ray film to reflect the vascular lumen.

For computed tomography (CT) or digital subtraction angiography (DSA), the serum iodine Concentration needs only to be between 2 and 8 mg/ml.

Answer 14

SERUM IODINE CONCENTRATION

Question 15

An estimated one of every 20,000 to 40,000 patients receiving ROCM dies as a result of these adverse effects.

Although the odds of death appear low, they become very real if it happens to you or your patient. Thus, it is paramount that the technologist understand adverse effects so that proper actions can be instituted as rapidly as possible.

Answer 15

ADVERSE PHARMACODYNAMICS

Question 16

• Various physiologic effects.
• Intravascular administration of ROCM will cause a transient rise in intravascular osmotic pressure.
• These effects will cause fluid extraction from red blood cells (RBCs),endothelium, and theextravascular space.

Answer 16

OSMOLALITY EFFECTS

Question 17

• These receptors cause the autonomic nervous system to slow down the heart rate (bradycardia) and produce a drop in aortic pressure.

• patient may faint or lose consciousness which ahs been referred to as a vasovagal reaction

Answer 17

BARORECEPTORS & CHEMORECEPTORS

Question 18

ROCM can chelate (bind to) calcium cardiovascular system after injection.

Answer 18

CHELATION EFFECTS

Question 19

May be one pharmacodynamic mechanism by which adverse heart rhythms, such as pulseless electrical activity (PEA), cardiac arrest, and sudden death, occur in a minority of patients receiving intravascular ROCM.

Answer 19

CALCIUM CHELATION

Question 20

CHELATION EFFECTS

Answer 20

PULSELESS ELECTRICAL ACTIVITY (PEA)
CARDIAC ARREST

Question 21

A heart rhythm disturbance characterized by electrical impulses without cardiac contraction. The heart monitor shows electrical activity, but the heart is not pumping.

Answer 21

PULSELESS ELECTRICAL ACTIVITY (PEA)

Question 22

The heart has ceased to pump blood effectively to maintain life

Answer 22

CARDIAC ARREST

Question 23

This can theoretically result in bleeding and bruising episodes. Low-osmolality ROCM do not appear to produce anticoagulant effects.

Answer 23

ANTICOAGULATION EFFECTS

Question 24

The immune system is highly complex and consists of various components, including physical barriers and biochemical defenses.

• The biochemical defenses are thought to have a role in the immediately life-threatening reaction mimicking an anaphylactic reaction that can occur with ROCM.

Answer 24

IMMUNE SYSTEM-LIKE EFFECTS

Question 25

• A life-threatening, systemic hypersensitivity reaction. • Patients suffering anaphylaxis may exhibit any combination of nausea, vomiting, diarrhea, hives, rash, flushing, cyanosis, pallor, lightheadedness, unconsciousness, seizures, stridor, wheezing, respiratory distress, bronchospasm, & etc.

Answer 25

ANAPHYLAXIS (type I hypersensitivity reaction)

Question 26

ROCM are responsible for approximately 10% of all acute renal failure (ARF) events and are the third most common cause of hospital-acquired ARF.

Answer 26

RENAL DYSFUNCTION

Question 27

Urine output does not exceed 400 ml/day in these patients. The renal failure may not be reversible, and the serum creatinine does not normalize.

Answer 27

OLIGURIC ARF

Question 28

• New agent for treating hypertensive emergencies • This medication has potent vasodilatory effects through stimulation of the dopamine-1 receptor.

Answer 28

FENOLDOPAM

Question 29

Available as a 10% or 20% (100 or 200 mg/ml) respiratory nebulization solution and as an IV form.

Answer 29

ACETYLCYSTEINE

Question 30

Effects of sodium bicarbonate IV solution possible prophylactic strategy against development of renal failure secondary to ROCM.

Answer 30

SODIUM BICARBONATE

Question 31

• Occurs in patients who have decompensated thyrotoxicosis, a condition in which the body becomes unable to tolerate thyroid hormones. • Signs and symptoms of thyroid storm include fever, tachycardia (rapid heart rate), diaphoresis (sweating), agitation, nervousness, and emotional instability

Answer 31

THYROID STORM

Question 32

Include nausea, vomiting, flushing with a generalized feeling of warmth, rhinitis, lacrimation, sneezing, itching, rash, angioedema, generalized edema, cramps, excessive salivation, salivary gland swelling, diaphoresis, retching and choking, metallic taste in mouth, decreased white blood cells, chills, fever,and disseminated intravascular coagulation (DIC).

Answer 32

GENERAL ADVERSE REACTIONS

Question 33

Vasovagal reactions,hypotension, hypertension, syncope,tachycardia, pallor,chest pain, and cardiac arrest.

Answer 33

CARDIOVASCULAR EVENTS

Question 34

Dizziness, paresthesias, drowsiness, weakness, thirst, headache, and seizures.

Answer 34

CNS ADVERSE EFFECTS

Question 35

General gastric pain, nausea, vomiting, sialorrhea (excessive salivation), xerostomia (too little salivation), and dysgeusia (bad taste in mouth).

Answer 35

GASTROINTESTINAL ADVERSE EFFECTS

Question 36

Adverse effects that may be seen after the use of the ferumoxide compounds (iron compounds), such as ferumoxtran-10 (Combidex), iron oxide (Clariscan), and ferumoxytol, include hypotension if infused too rapidly; it is recommended not to exceed 25 to 30 ml/hr.

Answer 36

FERUMOXIDE COMPOUNDS

Question 37

Adverse effects from the manganese compounds, such as mangafodipir trisodium (Teslascan), may include chest pain and "mare forceful heartbeat," peripheral vasodilation (flushing), headache, dizziness, lightheadedness, (flushing), nausea dyspepsia,vomiting, and abdominal pain.

Answer 37

MANGANESE COMPOUNDS

Question 38

Adverse effects include QT prolongation on the electrocardiogram in up to 30% of patients administered perflutren. Dizziness, ventricular dysrhythmias, and chest pain occur infrequently with either octafluoropropane albumin microspheres or perflutren.

Answer 38

ULTRASOUND MICROBUBBLE AGENT ADVERSE REACTIONS

Question 39

has been reported in numerous patients receiving the albumin microsphere octafluoropropane.

Answer 39

Anaphylaxis

Question 40

The imaging technologist should use a screening method that includes the assessment of patient medical history and current renal function status

Answer 40

SCREENING

Question 41

Box 7-1 QUESTIONS TO BE ANSWERED BEFORE ADMINISTRATION OF ROCM

Answer 41

1. History of allergies to medications? 2. History of intolerance to iodine? 3. History of adverse reactions to radiopaque contrast media? 4. History of asthma or breathing difficulties? 5. History of cardiac disease? a. Congestive failure b. Cardiac dysrhythmias c. Hypertension d. Hypotension 6. History of renal disease? .Chronic renal failure a b. Acute renal failure c. Current blood urea nitrogen (BUN) concentration (renal function test) d. Current serum creatinine concentration (renal function test) 7. Current medications? 8. History of diabetes? 9. History of sickle cell anemia (in black patients)? 10. History of multiple myeloma? 11. Is the patient pregnant (females)? 12. Current central nervous system trauma?

Question 42

IV drug may be required to improve visualization in vascular bed or a to Counteract severe adverse effects that may result from ROCM.

Answer 42

DRUG-DRUG INTERACTIONS

Question 43

• May occur between ROCM and these adjunct drugs. • Chemical incompatibilities that produce insoluble precipitates can theoretically lead to occlusion of IV catheters and chemically induced embolism that can occlude small vessels in its path.

Answer 43

DRUG-DRUG INTERACTIONS

Question 44

In the GI tract, barium sulfate produces an insoluble precipitate with calcium to form barium fecaliths effects

Answer 44

BARIUM SULFATE

Question 45

of barium sulfate into the lungs generally does not cause harm, provided the amount aspirated is small

Answer 45

Aspiration

Question 46

Can cause both gastrointestinal (GI) and respiratory adverse.

Answer 46

ENTERAL BARIUM SULFATE

Question 47

Six rights of drug

Answer 47

the right drug the right patient the right time the right location the right documentation

Question 48

The drug ordered is appropriate for the patient.

Answer 48

THE RIGHT DRUG

Question 49

Medication is given to the intended patient

Answer 49

THE RIGHT PATIENT

Question 50

Give the medication at the right time ordered according to agency policy.

Answer 50

THE RIGHT TIME

Question 51

Give the medication by the ordered route.

Answer 51

THE RIGHT LOCATION

Question 52

Document medication administrattion after giving it, not before

Answer 52

THE RIGHT DOCUMENTATION