From the FDA Drug Label
Highest concentrations (300 and 400 mEq/L) should be exclusively administered via central route The maximum allowed concentration of KCL for IV administration through a central line is 400 mEq/L 1 and 1.
- The administration of concentrations higher than 400 mEq/L is not recommended.
- Central route administration is recommended for thorough dilution by the bloodstream and avoidance of extravasation.
From the Research
The maximum allowed concentration of KCl for IV administration through a central line is 200 mEq/L, as demonstrated by a study where 20 mEq KCl was dissolved in a 100 cc 5% dextrose in sterile water bolus over 1 hour through a subclavian central vein catheter 2. When administering potassium chloride through a central venous catheter, this higher concentration is permissible because the medication is rapidly diluted by the greater blood flow in large central veins, reducing the risk of vein irritation and phlebitis. Some key points to consider when administering KCl through a central line include:
- The concentration and rate of administration should be carefully controlled using an infusion pump with appropriate safeguards.
- The maximum recommended infusion rate is generally 10-20 mEq/hour for non-urgent replacement and up to 40 mEq/hour in critical situations with cardiac monitoring.
- Careful monitoring of serum potassium levels and cardiac function is essential during administration of concentrated KCl solutions. It's also important to note that the evidence from other studies, such as 3, 4, 5, and 6, may not be directly relevant to the question of maximum allowed concentration of KCl for IV administration through a central line, but they do provide useful information on the management of hypokalemia and hyperkalemia, as well as the comparative dose response of intravenous versus enteral potassium administration. However, the study 2 provides the most relevant and recent evidence for the maximum allowed concentration of KCl for IV administration through a central line.