ATI RN
Pharmacology Final ATI Quizlet Questions
Question 1 of 9
A 22-year-old woman ingests an entire bottle of acetaminophen in an attempted suicide. She unexpectedly feels well for the next 24 h, at which time her boyfriend discovers what she has done and takes her to the ER. The toxic metabolite of acetaminophen exerts its deleterious effect by what mechanism?
Correct Answer: A
Rationale: Acetaminophen overdose initially presents asymptomatically, but its toxic metabolite, NAPQI, causes delayed harm. Option , depletion of endogenous antioxidants (glutathione), is correct-NAPQI, formed via CYP450 metabolism, overwhelms glutathione, leading to oxidative stress and hepatotoxicity. Option , hapten formation, occurs with some drugs but not acetaminophen's primary toxicity. Option , cytochrome C oxidase inhibition, is cyanide's mechanism, not acetaminophen's. Option , ischemia from reduced blood flow, isn't the issue-damage is metabolic. Option (E), gallbladder paralysis, is irrelevant. NAPQI's glutathione depletion disrupts detoxification, causing centrilobular necrosis, explaining the delayed presentation and justifying urgent treatment like N-acetylcysteine to replenish glutathione.
Question 2 of 9
When administering a standard or median effective dose to a patient, the nurse explains that this amount of drug will have which effect?
Correct Answer: C
Rationale: Median effective dose (ED50) affects 50% of a population, a statistical pharmacodynamic measure, not individual guarantee. No adverse effects isn't assured-safety varies. Metabolism timing depends on half-life, not ED50. Majority effectiveness exceeds 50%. Half the population defines ED50, explaining its intent.
Question 3 of 9
The nurse is preparing to administer heparin to a client. Which laboratory value should the nurse check prior to administration?
Correct Answer: B
Rationale: Heparin, an anticoagulant, prolongs clotting via antithrombin, monitored by aPTT to ensure therapeutic range (1.5-2.5 times normal) and prevent bleeding or clotting risks. PT/INR (choices A, C) track warfarin, not heparin. Platelet count matters for heparin-induced thrombocytopenia but isn't the primary pre-dose check'baseline and periodic counts suffice. aPTT directly reflects heparin's effect, guiding dosing adjustments, especially in acute settings like DVT or PE. Checking it ensures safety, as excessive anticoagulation causes hemorrhage, while under-dosing fails therapy. This aligns with heparin's rapid action and short half-life, making B the critical lab value to verify before administration.
Question 4 of 9
What is levothyroxine's pharmacologic classification?
Correct Answer: A
Rationale: Levothyroxine belongs to the pharmacologic classification of thyroid preparations. It is a synthetic form of the thyroid hormone thyroxine (T4) and is used to treat hypothyroidism by supplementing or replacing the body's own thyroid hormone. Levothyroxine works to normalize thyroid hormone levels in the body and help regulate metabolism. It is not a metabolic inhibitor, analgesic, or loop diuretic.
Question 5 of 9
Regarding first pass metabolism:
Correct Answer: A
Rationale: The extraction ratio (ER = hepatic clearance / liver blood flow) quantifies first-pass metabolism's impact on bioavailability (F = 1 - ER), a true statement. It doesn't directly affect volume of distribution, which is a distribution parameter, so that's false. Oral morphine's bioavailability is ~20-30%, not exactly 15%, but close, though false per key. Phenytoin's extraction ratio is low, not high, due to capacity-limited metabolism. Lidocaine's high first-pass effect prevents oral efficacy, true. The ER formula is foundational in pharmacokinetics, predicting oral drug availability.
Question 6 of 9
When the nurse is administering topical nitroglycerin ointment, which technique is correct?
Correct Answer: D
Rationale: The correct technique when administering topical nitroglycerin ointment is to remove the old ointment before applying the new ointment. This is to prevent any potential overdosing of the medication, as nitroglycerin can be rapidly absorbed through the skin. It is important to ensure that the previous application is fully removed before applying a new dose to prevent any accumulation of the medication.
Question 7 of 9
A patient is in an urgent care center and is receiving treatment for mild hyponatremia after spending several hours doing gardening work in the heat of the day. The nurse expects that which drug therapy will be used to treat this condition?
Correct Answer: C
Rationale: In the context of mild hyponatremia, which is a condition where there is a lower-than-normal concentration of sodium in the blood, treatment often involves administering intravenous normal saline infusion administered slowly. This helps to incrementally increase sodium levels in the blood while also ensuring proper hydration. Normal saline is preferred over other fluid solutions as it helps to maintain a stable electrolyte balance. In cases of severe hyponatremia or symptoms like seizures, more aggressive treatment may be necessary, but for mild cases like that described in the scenario, normal saline infusion is typically the appropriate choice.
Question 8 of 9
The following statements concerning renal drug handling are correct:
Correct Answer: B
Rationale: The kidneys filter approximately 130 mL/min of protein-free plasma, which is the glomerular filtration rate in healthy adults.
Question 9 of 9
The ability of epinephrine to cause hyperglycemia is due to;
Correct Answer: C
Rationale: The ability of epinephrine to cause hyperglycemia is primarily due to its effect on alpha adrenoreceptors in the pancreatic islets of Langerhans. Epinephrine, acting through these alpha adrenoreceptors, inhibits the release of insulin from beta cells in response to elevated blood glucose levels. This results in decreased uptake of glucose by cells, leading to increased blood glucose levels, ultimately causing hyperglycemia. Other effects of epinephrine, such as vasoconstriction and increased heart rate, also contribute to the overall stress response, but the inhibition of insulin release through alpha adrenoreceptors is the main mechanism responsible for its hyperglycemic effects.