When preparing a mixed insulin dose containing NPH and regular insulin, which is the first preparatory step the nurse should perform?

When preparing a mixed insulin dose containing NPH and regular insulin, which is the first preparatory step the nurse should perform?

• A. Draw up the correct dosage of NPH insulin into the syringe.
• B. Draw up the correct dosage of regular insulin into the syringe.
• C. Inject air equal to the amount of NPH insulin prescribed into the vial of NPH insulin.
• D. Inject air equal to the amount of regular insulin prescribed into the vial of regular insulin.

Answer: (C)

The main idea is that when mixing two insulins in one syringe, you prepare each vial by first introducing air equal to the dose you plan to withdraw, to prevent vacuum and to make drawing up the correct amounts easier. By injecting air into the NPH vial first, you equalize the pressure in that vial so you can later withdraw the NPH without resistance and with accuracy. This step sets up the sequence for the rest of the preparation, after which you would inject air into the regular insulin vial for its dose and then draw up the regular insulin first, followed by the NPH. Following this order helps ensure the right proportions are in the syringe and reduces the risk of drawing up the wrong insulin or encountering air pockets.

The main idea is that when mixing two insulins in one syringe, you prepare each vial by first introducing air equal to the dose you plan to withdraw, to prevent vacuum and to make drawing up the correct amounts easier. By injecting air into the NPH vial first, you equalize the pressure in that vial so you can later withdraw the NPH without resistance and with accuracy. This step sets up the sequence for the rest of the preparation, after which you would inject air into the regular insulin vial for its dose and then draw up the regular insulin first, followed by the NPH. Following this order helps ensure the right proportions are in the syringe and reduces the risk of drawing up the wrong insulin or encountering air pockets.