Insulin adsorption by infusion sets in the setting of treatment of hyperkalaemia
Critical hyperkalaemia is a potentially life-threatening emergency, requiring timely treatment with an intravenous infusion of a combination of glucose and soluble insulin. Most intravenous infusion systems use polyvinyl chloride (PVC) or polyurethane tubings, which are hydrophobic and adsorb insulin.
Insulin adsorption is dependent on the infusion rate, insulin concentration, tubing material, and whether the tubing surface has been primed. Insulin adsorption on various infusion tubings has been studied in the setting of glycaemic control, where losses of > 50 % of insulin activity has been reported, and occurs mostly in the first 30 min of infusion. We examined the extent of insulin adsorption in syringe and burette delivery systems for intravenous insulin infusion in the setting of treatment of hyperkalaemia, which typically uses infusion rates much higher than for glycaemic control.