ATI LPN
Pediatric Nursing Cardiac Practice Questions Questions
Question 1 of 5
Hereditary methaemoglobinaemia is most commonly due to deficiency of which red cell enzyme?
Correct Answer: A
Rationale: Hereditary methemoglobinemia is most commonly due to cytochrome b5 reductase deficiency (Choice A), impairing reduction of methemoglobin to hemoglobin, causing cyanosis. Glutathione peroxidase (Choice B) protects against oxidative stress, not methemoglobin. Heme oxygenase (Choice C) degrades heme, unrelated here. Methylenetetrahydrofolate reductase (Choice D) affects folate metabolism. Cytochrome b5 reductase is the key enzyme.
Question 2 of 5
In newborns with polycythemia, highly elevated viscosity is due to:
Correct Answer: A
Rationale: Polycythemia increases viscosity primarily via a high RBC count , raising hematocrit (AAP). Plasma volume contributes less, and capillary factors (C-E) are secondary.
Question 3 of 5
Most common cause of severe mental retardation is:
Correct Answer: A
Rationale: Chromosomal disorders , like Down syndrome, are the top cause of severe mental retardation due to prevalence and impact (CDC). B-E are less frequent.
Question 4 of 5
Best diagnostic study to diagnose patients with adrenoleukodystrophy is:
Correct Answer: A
Rationale: Elevated VLCFA in plasma and RBCs confirms adrenoleukodystrophy diagnosis (NORD). B-E are incorrect.
Question 5 of 5
All of the following statements are true except:
Correct Answer: A
Rationale: Choice A is false; gloves don’t replace handwashing (CDC). B-E are true.