IV K mix

 Q: Intravenous (IV) infusion of potassium should be given in mix with? (select one)

A) Dextrose

B) Saline

Answer: B

The effect of giving IV potassium in dextrose mix can be detrimental. A dose of 20 mEq/L of potassium given in dextrose mix can cause a transient drop of potassium of 0.2 to 1.4 mEq/L. This may bear consequences in cardiac patients with arrhythmia, first demonstrated almost 60 years ago (reference # 2). This is due to the endogenous insulin released in response to a carbohydrate load. 

A similar impact can be seen in patients with underlying poor nutrition who gets high carbohydrate load via tube feeding, which is one of the manifestations of the refeeding syndrome.

#endocrinology

#electrolytes

References:

1. Gennari FJ. Hypokalemia. N Engl J Med 1998; 339:451. 

2. KUNIN AS, SURAWICZ B, SIMS EA. Decrease in serum potassium concentrations and appearance of cardiac arrhythmias during infusion of potassium with glucose in potassium-depleted patients. N Engl J Med 1962; 266:228. 

3. Fuentebella J, Kerner JA. Refeeding syndrome. Pediatr Clin North Am 2009; 56:1201.