![]() 20 mg is 4 to 8 times the usual dose for asthma. ![]() Nebulized albuterol is effective at moving potassium inside cells, but the necessary dose of 20 mg is not practical to give. Either way, it is prudent to check a fingerstick 1 hour after giving IV insulin+dextrose to treat hyperkalemia. Even if the patient is already hyperglycemic, some IV dextrose should be given to ensure hypoglycemia does not develop. This should be followed with 25-50 grams of IV dextrose to prevent hypoglycemia. Giving 10 units of regular insulin IV should be enough to lower the potassium to a safe level. I think of insulin like a key that unlocks a door in cell membranes to allow glucose, potassium, and water to walk through. IV insulin (followed by IV dextrose to prevent hypoglycemia) While there are 3 strategies for moving potassium inside of cells, only one of them is worth considering routinely in patients with hyperkalemia. This is why a couple extra mEq/L of potassium doesn’t do any harm inside cells, but has a tremendous impact on the outside of cells. The intracellular concentrations of sodium and potassium are essentially the reverse of the plasma concentrations. The cardiac membrane stabilization effects of calcium last 30-60 minutes, so immediately following calcium administration it is time to work on moving the excess potassium into the intracellular space where it won’t harm the cardiac membrane. Whether calcium chloride or calcium gluconate is used, the dose should be repeated if the ECG change has not normalized within 5 minutes of administration. The dose for severe hyperkalemia is 2-3 grams IV infusion over 15-20 minutes. Calcium gluconate is best used if the patient has a small, peripheral IV line and can tolerate waiting ~15 minutes for the dose to infuse. It must be given at a slower rate of 150 mg/minute to avoid hypotension. The dose for severe hyperkalemia is 1 gram IV push over 1 minute.Ĭalcium gluconate is less potent, and causes less irritation. ![]() The two forms are calcium chloride and calcium gluconate.Ĭalcium chloride can be given IV push, but causes a significant amount of phlebitis and tissue injury in extravasation so it is best used if there is a life threatening arrhythmia present or a central line is in place. Two forms of calcium are available to be given IV, and they have a few important differences. IV calcium works within minutes to protect cardiac membranes from the deleterious effects of hyperkalemia. Protect the cardiac membrane with IV calcium Remove the excess potassium from the patient Protect the cardiac membrane with IV calciumģ. In my experience a pharmacist at the bedside can play a significant role in ensuring the steps are followed in the proper order. ![]() Treatment of severe hyperkalemia should follow a 3 step process. Sending a VBG is the fastest way to get a sodium, potassium, glucose, and free calcium level at my hospital with a turn-around time of 15 minutes or less. If hyperkalemia is suspected and you don’t have point of care testing, the fastest way to get the serum potassium is to send a venous blood gas (VBG) sample to the lab for analysis. Note the T waves remain peaked but the P waves and QRS interval have normalized: Don’t bother trying to learn at which level of potassium the ECG changes occur – the changes do not correlate well with the serum potassium concentration.Īn ECG from a patient with a serum potassium of 7.5 with flattened P waves, widened QRS interval, and peaked T waves:Īn ECG from the same patient after correction of the serum potassium has begun. The P wave may disappear, and ultimately the QRS widens further to a sine wave until asystole occurs. While a patient with severe hyperkalemia can progress from any level of ECG change to ventricular tachycardia / ventricular fibrillation / asystole, in general a peaked T wave with shortened QT interval is the earliest change, followed by progressive lengthening of the PR interval and QRS duration. In a patient without chronically high potassium, a value lower than 7 may still have severe consequences. Severe hyperkalemia can be recognized by cardiac conduction abnormalities on ECG, muscle weakness / paralysis, or a serum potassium value greater than 7. Subscribe on iTunes, Android, or Stitcher ![]()
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