The nurse prepares to administer digoxin 0.125 mg PO to a client who has chronic heart failure. The laboratory report reveals a digoxin level of 2.5 mg/mL. Which nursing action is most appropriate at this time?

Choice A reason: This is the most concerning result for the nurse. Creatinine is a waste product of muscle metabolism that is filtered by the kidneys and excreted in the urine. A high creatinine level indicates impaired kidney function, which can be a complication of hypertension. The normal range of creatinine is 0.6 to 1.2 mg/dL for men and 0.5 to 1.1 mg/dL for women. A creatinine level of 3.2 mg/dL is more than twice the upper limit of normal and suggests severe kidney damage.

Choice B reason: This is not a concerning result for the nurse. Potassium is an electrolyte that is essential for the function of nerves and muscles, especially the heart. The normal range of potassium is 3.5 to 5.0 mEq/L. A potassium level of 3.4 mEq/L is slightly below the normal range, but not enough to cause serious problems. A low potassium level can be caused by diuretics, vomiting, diarrhea, or excessive sweating. The nurse should monitor the client's potassium level and symptoms, and advise the client to eat foods that are high in potassium, such as bananas, oranges, potatoes, and tomatoes.

Choice C reason: This is not a concerning result for the nurse. Hemoglobin is a protein in the red blood cells that carries oxygen to the tissues. The normal range of hemoglobin is 13.5 to 17.5 g/dL for men and 12.0 to 15.5 g/dL for women. A hemoglobin level of 12.8 g/dL is within the normal range for women and slightly below the normal range for men, but not enough to cause significant anemia. A low hemoglobin level can be caused by blood loss, iron deficiency, or bone marrow disorders. The nurse should assess the client's history, diet, and symptoms, and check for other signs of anemia, such as pallor, fatigue, and shortness of breath.

Choice D reason: This is not a concerning result for the nurse. Blood urea nitrogen (BUN) is a waste product of protein metabolism that is filtered by the kidneys and excreted in the urine. A high BUN level indicates impaired kidney function or dehydration. The normal range of BUN is 7 to 20 mg/dL. A BUN level of 20 mg/dL is at the upper limit of normal, but not enough to indicate serious kidney problems. The nurse should ensure that the client is well hydrated and monitor the client's urine output and specific gravity.

Choice A reason: Vitamin B12 does not contribute to the increased production of RBCs after significant blood loss. Vitamin B12 is a type of vitamin that is essential for the normal formation and maturation of red blood cells (RBCs), which carry oxygen throughout the body. ¹ However, vitamin B12 does not increase the production of RBCs in response to blood loss. That is the role of erythropoietin, a hormone that stimulates the bone marrow to produce more RBCs. ²

Choice B reason: Vitamin B12 is not needed to prevent excessive production of red blood cells. Vitamin B12 is needed for the normal production of red blood cells, not for the prevention of overproduction. Excessive production of red blood cells, also known as polycythemia, can cause the blood to become thick and viscous, increasing the risk of clotting and stroke. ³ Polycythemia can be caused by various factors, such as smoking, dehydration, or genetic mutations, but not by a lack of vitamin B12.

Choice C reason: Vitamin B12 is not needed to prevent RBCs from sticking together. Vitamin B12 is needed for the normal formation and maturation of RBCs, not for the prevention of aggregation. RBCs can stick together and form clumps, also known as rouleaux, which can impair blood flow and oxygen delivery. Rouleaux can be caused by various factors, such as inflammation, infection, or cancer, but not by a lack of vitamin B12.

Choice D reason: Vitamin B12 is needed for the normal formation and maturation of RBCs, but it cannot be absorbed by the body without a substance called intrinsic factor. Intrinsic factor is a protein that is produced by the stomach and binds to vitamin B12, allowing it to be absorbed by the small intestine. ¹ Pernicious anemia is a type of anemia that occurs when the stomach does not produce enough intrinsic factor, leading to vitamin B12 deficiency. The only way to treat pernicious anemia is by giving vitamin B12 injections, which bypass the need for intrinsic factor.