A nurse is caring for a client who is developing signs of hemorrhage after 5 days of continuous warfarin use. Which of the following labs should the nurse utilize to determine the medication's current therapeutic level?

Rationale:

A. Simvastatin is not typically associated with lowering heart rate as a side effect. This statement is incorrect.

B. Rhabdomyolysis, a severe side effect of statin medications like simvastatin, can cause dark urine due to the presence of myoglobin from muscle breakdown. Therefore, it is important for the client to report any dark urine to their healthcare provider.

C. Black stool is not a common side effect of simvastatin. This statement is incorrect.

D. Dizziness when standing is not a common side effect of simvastatin. This statement is incorrect.

Rationale:

A. Heparin and warfarin do not work to lower blood pressure. Their primary action is to prevent blood clots, not to affect blood pressure.

B. While heparin can help prevent the extension of existing blood clots, it does not typically dissolve clots. Warfarin is used for long-term anticoagulation and works by inhibiting the synthesis of clotting factors.

C. Heparin is often used initially to rapidly anticoagulate a patient while waiting for the therapeutic effects of warfarin to take effect. Warfarin is then used long-term to prevent future clots from forming.

D. Heparin and warfarin are often given together initially, especially in certain clinical situations such as acute deep vein thrombosis or pulmonary embolism, to achieve rapid anticoagulation while waiting for the therapeutic effects of warfarin. However, careful monitoring is required to minimize the risk of hemorrhage.