Chris asks the nurse whether all donor blood products are cross-matched with the recipient to prevent a transfusion reaction. Which of the following always require cross-matching?

Correct Answer: D

Rationale: Packed red blood cells (PRBCs) always require cross-matching to ensure compatibility between the donor and recipient blood types. Cross-matching involves testing the recipient's serum against the donor's red cells to detect antibodies that could cause a transfusion reaction. Granulocytes, platelets, and plasma do not require cross-matching in the same way, although they may undergo other compatibility tests. PRBCs are the most critical to match correctly due to the risk of hemolytic reactions, which can be life-threatening.

Correct Answer: D

Rationale: Magnesium sulfate prevents seizures in preeclampsia via CNS depression. Absence of seizures indicates therapeutic effect, the primary goal. Decreased BP isn't magnesium's role'antihypertensives manage that. Increased urine output isn't specific. Reduced reflexes signal toxicity, not efficacy. Seizure prevention aligns with magnesium's mechanism, critical in preeclampsia where eclamptic risk is high, making D the key finding of successful therapy.

Correct Answer: B

Rationale: Omeprazole is classified as an anti-ulcer agent. It belongs to a class of medications known as proton pump inhibitors (PPIs) that work by reducing the amount of acid produced in the stomach. Omeprazole is commonly used to treat conditions such as gastroesophageal reflux disease (GERD), ulcers, and Zollinger-Ellison syndrome. It is not a laxative, anti-heartburn medication, or antianemic drug.

Correct Answer: A

Rationale: For first-order kinetics, the rate of elimination is directly proportional to plasma drug concentration, ensuring constant percentage clearance over time.

Correct Answer: B

Rationale: Keratolytic drugs, such as salicylic acid, work by softening and removing the horny layer of the epidermis, which consists of dead skin cells. This helps treat conditions like psoriasis, warts, and calluses. They do not target the dermis (A), erythematous lesions (C), or hair follicles (D).