Reconstituting/Diluting a Medication
Any IV medication that requires preparation prior to administration should be done in a sterile compounding area (by the pharmacy personnel with optimal aseptic technique) However, at times, point of care preparation is necessary. So, let’s start with basics.
Basic principles of using a syringe/needle:
Basic technique to access a vial:
•Perform hand hygiene.
•The plastic cap on a vial is a dust cap and does not ensure sterility.
•Prior to puncturing of rubber seals or port of the vial, disinfect with an alcohol pad and allow to dry. Use a fresh pad for each vial.
•Set the vial on the counter and when entering the rubber stopper with a needle, entry is made with the beveled side of the needle up and with slight downward pressure. This technique is used to avoid coring of the rubber seal.
• Some hospitals may use blunt-tip needles to draw medication from a vial- this would be changed to a medication administration needle for an IM or SQ injection or removed for IV injection through a needleless port.
• Do not work with your hands above the vial you are working with to avoid particulates falling onto the cleaned surface.
• Do not touch the plunger surface- only touch the end of the plunger.
• Do not encircle the needle and syringe with your fingers while you have the needle in the vial- keep your hand behind the vial.
• Do not reuse the same syringe/needle to prepare more than 1 vial.
• Do not assume that the volume in a single-dose diluent vial is exactly what you need- there may be overfill.
• Do not touch your face or hair while working with an injectable product.
Reconstitution
Follow the principles of Standard Aseptic Non-Touch Technique (ANTT®) and vial preparation from above.
Select a syringe that is the appropriate size for the total volume (after reconstitution), add a needle if needed.
Pull back on the plunger to allow the entry of air that is equal to the volume of diluent to be added.
Carefully inject air into the diluent vial, and then pull back the desired volume for dilution.
To reconstitute a powder: Inject diluent into the powder vial – if it is a foamy solution, inject slowly and onto the wall of the vial. If you meet resistance, allow air back into the syringe to allow all the liquid into the vial.
If the medication dissolves readily, you can leave the needle/syringe in the vial (being careful not to touch the needle or plunger). Swirl the vial to dissolve the medication.
If it is a more difficult to dissolve medication, remove the needle/syringe (recap the needle) and swirl the vial or roll it between your palms (shaking may cause foaming or alter the potency of the drug). Re-swab the rubber stopper with alcohol before drawing up the medication.
Inspect the fluid for complete dissolution and to be sure there are no particulates.
Withdraw the proper dose.
Label the syringe with drug name, dose, and concentration after reconstitution. Administer promptly.
Dilution
Follow the principles of Standard Aseptic Non-Touch Technique (ANTT®) and vial preparation from above.
Select a syringe that is the appropriate size for the total volume after dilution, add needle.
Select appropriate single use vial of diluent based on drug requirements.
■ Pull back the syringe plunger until the volume of air drawn into the syringe equals the volume to be withdrawn from the diluent vial.
■ Without inverting the vial, insert the needle (or needleless access device) into the top of the vial, making sure that the needle’s bevel tip doesn’t touch the solution. Inject the air into the vial and withdraw the needle (or needleless access device). This step replaces air in the vial, which prevents the creation of a partial vacuum when you withdraw the drug.
■ Repeat the steps above for the second vial. Then, after injecting the air into the second vial, invert the vial, withdraw the prescribed dose, and then withdraw the needle.
■ Disinfect the rubber stopper of the first vial again, allow it to dry, and insert the needle (or needleless access device), taking care not to depress the plunger. Invert the vial, withdraw the prescribed dose, and then withdraw the needle (or needleless access device).
■ Change the needle (or needleless access device) on the syringe, if indicated, to a safety needle or use a tip cap.
Do not use a saline flush prefilled syringe as the diluent to reconstitute or dilute a medication.
Important Notes
• Do not use an IV bag as the source of diluent to reconstitute a medication.
• Do not transfer drugs from one syringe to another by injecting into the syringe tip
• Do not re-use a single dose vial for multiple doses or multiple patients.
• Do not dilute a medication supplied in a pre-filled, ready-to-use product.
• Do not use a prefilled product (e.g. carpuject style or insulin pen cartridge) as a vial by inserting a needle through the rubber stopper.
Mixing Insulin
Always use an insulin syringe marked in units.
*The Fast-acting insulin is drawn into the insulin syringe First*
1. Draw up the Fast-acting insulin into the syringe first.
2. Add air to the syringe by pulling plunger back to the total dose (fast + long-acting insulin = total units).
3. Slowly inject air into the long-acting insulin vial being careful to not inject any of the rapid-acting insulin.
4. Remove the proper amount of long-acting insulin by pulling back to the total insulin dose.
5. Remove vial from syringe, recap needle. Label with names and amounts of insulin.
References:
Dolan SA, Arias KM, Felizardo G, et al. APIC position paper: Safe injection, infusion, and medication vial practices in health care (2016). https://www.apic.org/Resource_/TinyMceFileManager/Position_Statements/2016APICSIPPositionPaper.pdf
Gorski, L.A., Hadaway, L., Hagle, M.E., et al. (2021) Infusion therapy standards of practice. J Infus Nurs.44(suppl 1):S1-S224.
ISMP Safe Practice Guidelines for Adult IV Push Medications. 2015. https://www.ismp.org/sites/default/files/attachments/2017-11/ISMP97-Guidelines-071415-3.%20FINAL.pdf
Lippincott. Lippincott Nursing Procedures . Wolters Kluwer Health. Kindle Edition.
Mosby’s Nursing Video Skills-Advanced https://www.ndsu.edu/pubweb/bismarcknursing/advanced/skill/U002.html [has text, procedure video, and printable guidelines and checklist]
WHO best practices for injections and related procedures toolkit. March 2010 https://www.ncbi.nlm.nih.gov/books/NBK138491/pdf/Bookshelf_NBK138491.pdf