A nurse is assessing a client who is receiving a unit of packed red blood cells. Which of the following findings is a manifestation of acute hemolytic reaction?

Choice A reason: Using IV tubing specific for heparin sodium when administering the infusion is not the correct action. Heparin sodium can be administered using any standard IV tubing, as long as it is primed with heparin solution to prevent clotting in the tubing.

Choice B reason: Administering 50,000 units of heparin by IV bolus every 12 hours is not the correct action. This is a very high dose of heparin that can cause bleeding complications. The usual dose of heparin for continuous IV infusion is 15 to 25 units/kg/hour, adjusted according to the aPTT results.

Choice C reason: Having vitamin K available on the nursing unit is not the correct action. Vitamin K is the antidote for warfarin, not heparin. Vitamin K reverses the effects of warfarin by increasing the synthesis of clotting factors in the liver.

Choice D reason: Checking the activated partial thromboplastin time (aPTT) every 4 hours is the correct action. The aPTT is a blood test that measures the time it takes for the blood to clot. It is used to monitor the effectiveness and safety of heparin therapy. The therapeutic range of aPTT for heparin is 1.5 to 2.5 times the normal value, or 60 to 80 seconds. The nurse should check the aPTT every 4 hours until it is within the therapeutic range, and then every 6 to 8 hours thereafter. The nurse should adjust the heparin infusion rate according to the aPTT results and the prescriber's orders.

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.