Final answer:
Kayexalate with sorbitol helps reduce plasma and total body potassium levels in patients with renal dysfunction by exchanging sodium for potassium in the intestines and inducing a laxative effect. Regular insulin redistributes potassium into cells. Calcium gluconate does not lower potassium levels but can stabilize the heart in hyperkalemia.
Step-by-step explanation:
The patient's potassium level is 7.0 mEq/L. Besides dialysis, to reduce plasma potassium levels and total body potassium content safely in a patient with renal dysfunction, Kayexalate with sorbitol is the most effective. Kayexalate (sodium polystyrene sulfonate) works by exchanging sodium for potassium in the intestines, thereby lowering the body's potassium levels. Adding sorbitol helps to induce a laxative effect, promoting the elimination of potassium from the body through stool. Regular insulin can also assist in this process by facilitating the uptake of potassium into cells, thus decreasing the extracellular potassium concentration. However, insulin does not reduce total body potassium; instead, it only helps to redistribute it intracellularly. Regular insulin usage would generally be supplemented with glucose to prevent hypoglycemia, and this combination can be particularly useful in acute settings. Calcium gluconate does not lower potassium but can be used to stabilize the cardiac membrane in the presence of hyperkalemia while other treatments take effect. It is not a treatment for lowering potassium on its own.