Mitch was started on normal saline with potassium as well as an insulin drip. Why are these fluids a component of his rehydration and correction of the HHS?

Question

What will be an ideal response?

Answer 1

• Normal saline delivered via an IV will restore the electrolyte imbalance that occurred due to HHS (more specifically, that occurred from osmotic diuresis). Sodium was lost during this process, which is why saline is administered. This will correct the severe state of dehydration more rapidly than drinking water.
• Potassium is another electrolyte that will be out of balance with dehydration. In addition, the patient is taking Dyazide, which is not a potassium-sparing diuretic. Therefore, potassium is commonly lost when using this medication. Although patient is not taking his diabetes medications, he claims to still be taking Dyazide to help with his blood pressure. Potassium is commonly lost in the urine with osmotic diuresis. This occurred because of the serious hyperosmolar state of the blood.
• The infusion of the potassium in the saline is due to the low levels of intracellular potassium. This potassium deficit is not apparent in Mitch's labs (3.9 and 4.0 mEq/L), but that is a measure of his serum levels which are typically normal or high in HHS patients. That is because the hypertonic and insulin-deficient bloodstream supports retention of potassium in the extracellular space. If potassium is not supplemented during rehydration and insulin infusion, hypokalemia will result as potassium rushes into the cells.
• Insulin is used to help correct the extremely high blood glucose levels. Since the patient has low levels of circulating insulin, which is associated with HHS, insulin is needed to help insulin-dependent tissues uptake glucose.