A nurse is caring for a client who has a central venous catheter and reports hearing a gurgling sound on the side of the catheter insertion. Which of the following complications should the nurse suspect?

Choice A reason: Taking the medication in the morning is not the correct instruction. Simvastatin is a statin drug that lowers cholesterol levels by inhibiting the enzyme that produces cholesterol in the liver. The liver produces more cholesterol at night, so simvastatin is more effective when taken in the evening or at bedtime.

Choice B reason: Avoiding grapefruit juice is the correct instruction. Grapefruit juice can increase the blood levels of simvastatin and cause serious side effects such as muscle damage, liver damage, and kidney failure. Grapefruit juice inhibits the enzyme that metabolizes simvastatin in the intestine, leading to higher concentrations of the drug in the bloodstream.

Choice C reason: Monitoring for ringing in the ears is not the correct instruction. Ringing in the ears, or tinnitus, is not a common or serious side effect of simvastatin. However, some other medications that lower cholesterol, such as niacin and gemfibrozil, can cause tinnitus. The client should report any unusual or persistent symptoms to the prescriber.

Choice D reason: Expecting brown-colored urine is not the correct instruction. Brown-colored urine, or hematuria, is not a normal or expected side effect of simvastatin. However, it may indicate a serious condition such as rhabdomyolysis, which is a rare but life-threatening complication of statin therapy. Rhabdomyolysis is the breakdown of muscle tissue that releases a protein called myoglobin into the bloodstream. Myoglobin can damage the kidneys and cause brown-colored urine. The client should seek immediate medical attention if they notice any signs of rhabdomyolysis, such as muscle pain, weakness, fever, or dark urine.

Choice A reason: Warfarin PO is not a suitable medication for DVT prophylaxis in the immediate postoperative period, as it has a slow onset of action and requires frequent monitoring of the INR (international normalized ratio). Warfarin may be used for long-term anticoagulation, but it is not effective for preventing the formation of new clots.

Choice B reason: Enoxaparin subcutaneous is a suitable medication for DVT prophylaxis in the immediate postoperative period, as it has a rapid onset of action and does not require frequent monitoring of the coagulation status. Enoxaparin is a low-molecular-weight heparin that inhibits the formation of thrombin and prevents the growth of existing clots.

Choice C reason: Aspirin PO is not a suitable medication for DVT prophylaxis in the immediate postoperative period, as it has a weak anticoagulant effect and may increase the risk of bleeding. Aspirin is an antiplatelet agent that inhibits the aggregation of platelets and prevents the formation of arterial clots, but it is not effective for preventing venous clots.

Choice D reason: Heparin infusion is not a suitable medication for DVT prophylaxis in the immediate postoperative period, as it requires continuous intravenous administration and frequent monitoring of the aPTT (activated partial thromboplastin time). Heparin is an unfractionated heparin that inhibits the formation of thrombin and prevents the growth of existing clots, but it has a narrow therapeutic window and a high risk of bleeding.