Question 361:
Levothyroxine (Synthroid) is the drug of choice for thyroid replacement therapy in clients with hypothyroidism because __________.
A. it is chemically stable, nonallergenic, and can be administered orally once a day
B. it is available in a single 25mg tablet, which makes dosing simple
C. it is not a prodrug
D. it has a short half-life
Correct Answer: A
Levothyroxine is safe and effective with virtually no side effects when dosed properly. A single, daily dose
is possible because of the long half-life (7 days).
Levothyroxine tablets are available in a wide range of concentrations to meet individual client
requirements.
Levothyroxine (T4) is a prodrug of T3.
Question 362:
The tendency of a drug to combine with its receptor is called __________.
A. potency
B. efficacy
C. kinetics
D. affinity
Correct Answer: D
Affinity is a close relationship, mutual attraction, or similarity.
The tendency of a drug to combine with its receptor is called affinity. Affinity is a measure of the strength of
the drug-receptor bonding.
Potency and efficacy describe the capability of a drug to produce the desired effect.
Kinetics is the branch of science that deals with the effects of forces on the motions of material bodies or
with changes in a physical or chemical system.
Question 363:
A 50 milliliter (ml) bolus of normal saline fluid is ordered by the physician. The physician wants it to infuse in 30 minutes.
The nurse should set the pump rate at __________.
A. 100 ml per hour for one hour
B. 60 ml per hour for one-half hour
C. 120 ml per hour for one hour
D. 50 ml per hour for one hour
Correct Answer: A
One hundred ml in one hour equals 50 ml in 30 minutes, which is what the physician prescribed.
60 ml per hour for one-half hour is 10 ml more than the physician prescribed for 30 minutes.
120 ml per hour for one hour is the same as 60 ml per hour for one-half hour; it is 10 ml more than the
physician prescribed for 30 minutes.
50 ml per hour for one hour only provides 25 ml over 30 minutes, or half the volume prescribed.
Question 364:
The primary organ for drug elimination is the __________.
A. skin
B. lung(s)
C. kidney(s)
D. liver
Correct Answer: C
Most drugs are excreted in the urine, either as the parent compound or as drug metabolites.
Relatively few drugs are excreted in sweat.
Some volatile gases are excreted with expiration.
The liver primarily metabolizes drugs. Some of them are excreted in bile, especially those with a molecular
weight above 300.
Question 365:
A complication of total parenteral nutrition (TPN) is the development of cholestasis.
What is this condition?
A. an inflammatory process of the extrahepatic bile ducts
B. an arrest of the normal flow of bile
C. an inflammation of the gallbladder
D. the formation of gallstones
Correct Answer: B
Cholestasis due to TPN administration is an intrahepatic process that interrupts the normal flow of bile.
Extrahepatic bile duct inflammation is cholangitis.
Inflammation of the gallbladder is cholecystitis.
Gallstones are formed by bile components.
Question 366:
The intravenous route is potentially the most dangerous route of drug administration because __________.
A. the IV might infiltrate
B. it is expensive and nursing intensive
C. rapid administration of a drug can lead to toxicity
D. the client always has more side effects
Correct Answer: C
The bioavailability of the injected medication is 100% and might lead to toxicity.
An IV infiltration can cause serious problems with tissue necrosis, but this is not life threatening.
Expensive and time consuming do not equate with dangerous.
Choice "the client always has more side effects" is not always true.
Question 367:
Some drugs are excreted into bile and delivered to the intestines. Prior to elimination from the body, the drug might be absorbed.
This process is known as __________.
A. hepatic clearance
B. total clearance
C. enterohepatic cycling
D. first-pass effect
Correct Answer: C
Drugs and drug metabolites with molecular weights higher than 300 can be excreted via the bile, stored in
the gallbladder, delivered to the intestines by the bile duct, and then reabsorbed into the circulation. This
process reduces the elimination of drugs and prolongs their half-life and duration of action in the body.
Hepatic clearance is the amount of drug eliminated by the liver.
Total clearance is the sum of all types of clearance including renal, hepatic, and respiratory.
First-pass effect is the amount of drug absorbed from the GI tract, then metabolized by the liver (reducing
the amount of drug that makes it into circulation).
Question 368:
Hormonal agents are used to treat some cancers.
An example is __________.
A. thyroxine to treat thyroid cancer.
B. ACTH to treat adrenal carcinoma.
C. estrogen antagonists to treat breast cancer.
D. glucagon to treat pancreatic carcinoma.
Correct Answer: C
Estrogen antagonists are used to treat estrogen hormone-dependent cancer, such as breast carcinoma.
A wellknown estrogen antagonist used in breast cancer therapy is Tamoxifen (Nolvadex). This drug, in
combination with surgery and other chemotherapeutic drugs, reduces breast cancer recurrence by 30%.
Estrogen antagonists can also be administered to prevent breast cancer in women who have a strong
family history of the disease.
Thyroxine is a natural thyroid hormone. It does not treat thyroid cancer.
ACTH is an anterior pituitary hormone that stimulates the adrenal glands to release glucocorticoids; it does
not treat adrenal cancer. Glucagon is a pancreatic alpha cell hormone that stimulates glycogenolysis and
gluconeogenesis; it does not treat pancreatic cancer.
Question 369:
A client's central venous access device (CVAD) becomes infected.
Why might the physician order antibiotics to be given through the line rather than through a peripheral IV line?
A. to prevent infiltration of the peripheral line
B. to reduce the pain and discomfort associated with antibiotic administration in a small vein
C. to lessen the chance of an allergic reaction to the antibiotic
D. to attempt to eliminate microorganisms in the catheter and prevent having to remove it
Correct Answer: D
Microorganisms that infect CVADs are often coagulase-negative staphylococci, which can be eliminated
by antibiotic administration through the catheter.
If unsuccessful in eliminating the microorganism, the CVAD must be removed.
CVAD use lessens the need for peripheral IV lines and thus the risk of infiltration. In this case, however,
the antibiotics are given to eradicate microorganisms from the CVAD. CVAD use has the effect described
in Choice "to reduce the pain and discomfort associated with antibiotic administration in a small vein", but
in this case, the antibiotics are given through the CVAD to eliminate the infective agent. The route does not
prevent an allergic reaction.
Question 370:
A client asks the nurse if all donor blood products are cross-matched with the recipient to prevent a transfusion reaction.
Which of the following always requires cross-matching?
A. packed red blood cells
B. platelets
C. plasma
D. granulocytes
Correct Answer: A
Packed red blood cells contain antigens and antibodies that must be matched between donor and
recipient.
Platelets, plasma and granulocytes do not contain red cells; thus, they require no cross-matching.