Purpose: To deliver the prescribed combination of insulin to the patient to control the blood glucose level without cross-contamination of medication.
● Regular insulin (unmodified insulin) is a rapid-acting, clear solution.
● Most other types of insulin are cloudy (modified) because of the addition of proteins, which slow the absorption of the drug, giving them an intermediate-to-long duration of action.
● Newer, long-acting insulins such as Lantus are clear but cannot be mixed with other insulins.
● Mixing guidelines:
• Regular insulin can be mixed with any other type of insulin and should always be drawn up in the syringe first.
• NPH (Neutral Protamine Hagedorn) insulin can only be mixed with regular insulin.
• Different types of Lente insulin can be mixed together, and with regular insulin, but not with any other type of insulin.
• Insulin syringes are calibrated in 50 or 100 units per milliliter. Care must be taken not to confuse the two, as each marking represents one unit on a 50-unit syringe and 2 units on a 100-unit syringe; that could lead to medication error.
• Insulin can be kept at room temperature for approximately 1 month. Refrigeration is required for longer periods of time. Insulin should not be given cold, but should be allowed to warm to room temperature.
• Have D50W, sugar, orange juice, and glucagon available on unit.
• If lispro (rapid acting) insulin is used, make sure meals are on unit; onset of action within 15 minutes.
• Do not use insulin that has changed color or has become clumped or granular in appearance.
• Regular and short-acting insulin should be clear; other types should be uniformly cloudy.
• Store unused insulin in a cool area; use room temperature insulin for injection to limit irritation at injection site.
• Mix insulin by gently rotating between palms.Do not shake; this creates air bubbles in the mixture and syringe thereby altering the dose delivered to the patient.
• Commercial insulin concentrations of 100 or 500 U/mL are available.
• 500 U/mL preparations are useful for the patient with insulin resistance who requires large doses, but should be stored separately to avoid an accidental overdose.
Relevant Nursing Diagnosis
Potential for injury related to medication error
Expected Outcome: The appropriate, prescribed combination of insulin will be drawn up in a single syringe without cross-contamination of insulin vials
1. Wash hands, rotate insulins in palms of hands for 1 minute (do not shake); clean vial stoppers with alcohol.
Rationale: Decreases microorganism transmission.
Rotating insulin resuspends the modified insulin and warms the medications. Shaking creates air bubbles that can alter dose.
2. Aspirate volume of air equivalent to the dosage of the modified (cloudy) insulin.
Rationale: Creates pressure to withdraw solution; avoids a vacuum that can cause cross-contamination.
3. Inject the air into the modified (cloudy) vial; do not touch the medication with the needle.
Rationale: Prevents cross-contamination.
4. Remove needle and syringe from vial and aspirate the amount of air equivalent with the unmodified, regular (clear) insulin dosage.
Rationale: Creates pressure to withdraw the desired amount of medication in syringe.
5. Insert the needle into the vial of unmodified, regular (clear) insulin and inject the air; then pull back on plunger to fill syringe with prescribed insulin dosage. Remove needle from vial by the barrel and not the plunger.Verify the dosage.
Rationale: Preparation of the first portion of insulin dosage. Prevents manipulation of plunger that may cause excess or loss of medication; ensures proper dosage prepared.
6. Calculate the amount on the syringe what the combined units of insulin should measure.
Rationale: Prevents inadvertent withdrawal of excess insulin from the second (cloudy) vial.
7. Insert needle into the modified (cloudy) insulin vial.Use care not to manipulate plunger and expel medication. Invert vial to withdraw desired amount of insulin in the syringe.
Rationale: Syringe will fill, owing to positive pressure in the vial; no need to aspirate.
8. Remove needle; expel excess air or fluid from the syringe.
Rationale: Air or insulin excess will incorrectly dose the patient.
9. Discard needle in sharps container and wash hands.
Rationale: Reduces transfer of microorganisms.
Evaluation and follow up activities
It is important to administer insulin mixture within 5 minutes of preparation.The action of regular insulin is reduced by its binding with NPH insulin