A client with acute renal failure presents with a serum potassium level of 6.8 mEq/L and tall, peaked T-waves on ECG. The physician orders 10% Calcium Gluconate IV. What is the primary therapeutic purpose of Calcium Gluconate in this emergency scenario?
Calcium Gluconate directly antagonizes the membrane excitability effects of hyperkalemia on cardiac tissue, raising the threshold potential and reducing the risk of fatal arrhythmias such as ventricular fibrillation. It does not lower serum potassium levels; insulin with dextrose or beta-2 agonists are used to shift potassium intracellularly.