Following long-term administration of warfarin sodium to a client with deep vein thrombosis, the nurse should expect which outcome?

Correct Answer: A

Rationale: After long-term warfarin for deep vein thrombosis, the nurse should expect the prothrombin time (PT) to be 1.5 to 2 times the normal value (or INR 2-3), indicating therapeutic anticoagulation. Warfarin inhibits vitamin K-dependent clotting factors, prolonging PT to prevent clot extension. PTT is more relevant for heparin, not warfarin, and hematocrit/hemoglobin levels aren't directly affected by anticoagulation unless bleeding occurs. PT prolongation is the standard measure of warfarin's efficacy in this context.

Correct Answer: C

Rationale: Glucose reabsorption occurs primarily in the proximal convoluted tubule (PCT). From the tubular lumen to the tubular cell, it uses secondary active transport via sodium-glucose cotransporters (SGLT), driven by the Na⁺ gradient established by Na⁺/K⁺-ATPase. From the cell to the peritubular capillary, glucose exits via facilitated diffusion (GLUT transporters), a passive process. This two-step mechanism distinguishes it from purely passive or primary active transport, making C correct.

Correct Answer: C

Rationale: The myogenic mechanism is the intrinsic ability of vascular smooth muscle, including renal arterioles, to constrict when blood pressure rises, maintaining stable GFR. This autoregulation protects glomeruli from hypertension. Hormonal (A) and sympathetic (B) controls involve external signals, and tubuloglomerular feedback (D) adjusts via macula densa, making C the correct intrinsic process.

Correct Answer: C

Rationale: Furosemide, a loop diuretic, inhibits the Na⁺/K⁺/2Cl⁻ cotransporter in the thick ascending limb of the Loop of Henle, blocking reabsorption of these ions, increasing urine output, and reducing blood volume. Thiazides (A) target the DCT, osmotic diuretics (B) work via osmolarity, and carbonic anhydrase inhibitors affect HCO₃⁻, making C correct.

Correct Answer: D

Rationale: In chronic metabolic acidosis, bone acts as an important buffer source, releasing calcium carbonate and phosphate to neutralize excess H⁺ over days to weeks, compensating when bicarbonate (C) is depleted. Phosphate (A) and proteins (B) buffer acutely but are less significant long-term, making D correct for chronic states.