Hyperkalemia

Steps

1. Put the patient on a cardiac monitor and get IV access. High potassium kills through arrhythmia, so the monitor is not optional.
2. Get a 12-lead ECG. Peaked T waves first, then a widening QRS. Changes on the ECG mean the heart is already irritable and the calcium cannot wait.
3. Give calcium gluconate 1 g IV over 10 minutes — first, before anything else. Gluconate, not chloride; chloride is for codes. It stabilises the cardiac membrane and does not lower the potassium at all. Start it running, then gather the rest. Up to 3 g initially if there is instability or arrhythmia.
4. Give 10 units of regular insulin IV with an ampoule of dextrose. Only regular insulin can go IV. Insulin drives potassium into the cell and takes the glucose down with it, which is what the dextrose is for. If the glucose is already low, or the patient is renal, ask — it may drop to 5 units.
5. Recheck a point-of-care glucose 30 minutes after the insulin. You have just given insulin to someone who may not need the sugar lowered.
6. Give sodium bicarbonate 50 mEq (one ampoule) IV. Acidosis pushes potassium out of cells and alkalosis pulls it back in. The bicarbonate creates that alkalosis.
7. Consider albuterol, Lasix and IV fluids. Albuterol shifts potassium into cells — check with the provider first if the patient is already tachycardic. Lasix only helps if they make urine, so it is mainly for dialysis patients. Fluids dilute what is in the blood.
8. Give Kayexalate — important, but last of the medications. Sodium polystyrene sulfonate: a powder given by mouth or as an enema. It binds potassium in the gut so it leaves in the stool — one of the few things that truly removes it rather than hiding it in cells. It takes 4–6 hours to start, which is why everything above goes first.
9. For severe hyperkalemia, arrange dialysis. The definitive treatment. A provider places an emergency large-bore catheter, and the dialysis department or RN has to be available.
10. Send a VBG alongside the BMP. A VBG returns a potassium far faster than the BMP. Send the BMP anyway.

Notes

Concerning above 6 mEq/L. Only three things actually remove potassium from the body — Kayexalate, Lasix and dialysis. Calcium, insulin, bicarbonate and albuterol buy time: calcium shields the heart without lowering the level at all, and the rest only hide potassium inside cells, from where it comes back. That is why the fast steps come first and the slow ones still have to be given. Doses follow the Metabolic and Endocrine Emergencies lecture; confirm them against your own facility protocol and the provider order.