Students – Paramedic Practice Exam

In a life-threatening hyperkalemic dysrhythmia, the priority is twofold: protect the heart and rapid reduction of potassium. Calcium chloride stabilizes the myocardial cell membranes, raising the threshold for depolarization so the risk of dangerous rhythms drops immediately. It doesn’t lower potassium itself, but it buys crucial time by preventing further electrical instability. Sodium bicarbonate helps by alkalinizing the blood, which drives potassium back into cells and can help counteract acidosis that often accompanies severe hyperkalemia. Using these together provides a rapid, synergistic crisis response: calcium stabilizes the heart right away, while bicarbonate nudges potassium into cells to lower the circulating level quickly. This combination is a common fast-acting approach while arranging definitive therapy such as dialysis if needed. Insulin with glucose also lowers potassium but doesn’t directly stabilize the heart, and dialysis, while definitive, is not always immediately available; the bicarbonate and calcium combo offers the most effective immediate crisis management.