A patient with a history of heart failure is prescribed furosemide (Lasix). Several days after the aggressive diuretic therapy started, the patient began to exhibit confusion, tremors, muscle cramps, and nausea.
What does the nurse suspect?

Atorvastatin is a type of statin, which are the most potent antilipidemic agents and have proven to lower the risk of myocardial infarction. Statins work by inhibiting an enzyme called HMG-CoA reductase, which is involved in the synthesis of cholesterol in the liver.By reducing the production of cholesterol, statins lower the levels of low-density lipoprotein (LDL) and triglycerides, and slightly increase the levels of high-density lipoprotein (HDL) in the blood.

Choice B, niacin, is wrong because niacin is not as effective as statins in lowering LDL and preventing cardiovascular events.Niacin is a water-soluble vitamin that can lower LDL and triglycerides, and increase HDL, but it can also cause flushing, itching, and liver toxicity.

Choice C, gemfibrozil, is wrong because gemfibrozil is a type of fibric acid derivative, which are mainly used to lower triglycerides and increase HDL, but have little effect on LDL.

Fibric acid derivatives work by activating a receptor called PPAR-alpha, which regulates the metabolism of lipids in the liver and muscle.Fibric acid derivatives can also increase the risk of gallstones and muscle damage.

Choice D, ezetimibe, is wrong because ezetimibe is a selective cholesterol absorption inhibitor, which blocks the absorption of dietary and biliary cholesterol in the intestine.Ezetimibe can lower LDL by about 15-20%, but it has not been shown to reduce the risk of myocardial infarction on its own.Ezetimibe is usually combined with a statin for better efficacy and safety.

Normal ranges for lipid levels are:

• Total cholesterol: less than 200 mg/dL

• LDL cholesterol: less than 100 mg/dL

• HDL cholesterol: more than 40 mg/dL for men and more than 50 mg/dL for women

• Triglycerides: less than 150 mg/dL

Hypokalemia is a condition of low potassium levels in the blood, which can be caused by diuretics such as furosemide (Lasix) that increase the excretion of potassium in the urine. Potassium is an important electrolyte that helps regulate the function of nerves and muscles, including the heart.Low potassium levels can cause symptoms such as confusion, tremors, muscle cramps, and nausea, which are consistent with the patient’s presentation.

Choice B, renal failure, is wrong because furosemide is used to treat fluid retention and edema caused by kidney disease, not to cause it.Renal failure would also cause symptoms such as decreased urine output, swelling, fatigue, and shortness of breath, which are not mentioned in the question.

Choice C, hyperkalemia, is wrong because hyperkalemia is a condition of high potassium levels in the blood, which can be caused by kidney disease or certain medications that decrease the excretion of potassium in the urine.Hyperkalemia can cause symptoms such as weakness, irregular heartbeat, paralysis, and chest pain, which are different from the patient’s symptoms.

Choice D, heart failure, is wrong because furosemide is also used to treat fluid retention and edema caused by heart failure, not to cause it.Heart failure would also cause symptoms such as shortness of breath, coughing, fatigue, and rapid weight gain, which are not mentioned in the question.

Normal ranges for potassium levels in the blood are 3.5 to 5.0 milliequivalents per liter (mEq/L) for adults and 3.4 to 4.7 mEq/L for children.

A level below 3.5 mEq/L is considered hypokalemic and a level above 5.0 mEq/L is considered hyperkalemic.