POTASSIUM

COURSES

Topics

The most common causes include:
- Kidney Disease.
- A diet high in potassium.
- Drugs that prevent the kidneys from losing enough potassium.
The most common cause of hyperkalemia is pseudohyperkalemia which is most commonly due to hemolysis of the sample.
Elevated potassium causes ECG changes in a dose-dependent manner:
- K = 5.5 to 6.5 mEq/L ECG will show tall, peaked t-waves
- K = 6.5 to 7.5 mEq/L ECG will show loss of p-waves
- K = 7 to 8 ECG mEq/L will show widening of the QRS complex
- K = 8 to 10 mEq/L will produce cardiac arrhythmias, sine wave pattern, and asystole
Treatment is usually prescribed in the following manner:
1. Exogenous sources of potassium should be immediately discontinued. Blood pressure medications and certain other drugs can raise your potassium levels.
2. Treatment of the reversible cause should begin along with the management of hyperkalemia.
3. Calcium therapy will stabilize the cardiac response to hyperkalemia and should be initiated first in the setting of cardiac toxicity.
4. Insulin and glucose, or insulin alone in hyperglycemic patients, will drive the potassium back into the cells, effectively lowering serum potassium. A common regimen is ten units of regular insulin given with 50 ml of a 50% dextrose solution (D50).
5. Dialysis. One may need dialysis if other treatments don’t lower your potassium levels or if you have kidney failure. Dialysis helps your kidneys remove excess potassium from your blood.