IM injection and calculation

Question 1

What should you do before an IM injection

Answer 1

Introduce yourself/Wash hands/Confirm the patient’s details/Explain the procedure
Check the patient’s understanding of the medication being given, and explain the indication for the medication.

Check for:

• allergies
• if the patient has a bleeding disorder or takes anticoagulant medication (possible contraindications).
• if the patient has a preferred injection site and if the patient is receiving regular IM injections, ensure that the injection sites are rotated.

Gain consent to proceed

Question 2

What equipment do you need for an IM injection?

Answer 2

Equipment tray
The medication to be administered
Patient’s prescription
Syringe – the smallest syringe that will accommodate the medication volume
Injecting needle – (21–23 gauge) – 25mm in length is standard
Drawing up needle / Blunt filter needle (these filter out sub-visible particles of glass, rubber and other residues when drawing up from glass ampoules)
Antiseptic swab – 70% isopropyl alcohol wipe
Gauze or cotton swab
Sharps container (for disposal of the needles)
Apron
Non-sterile gloves

Question 3

What are the 7 rights?

Answer 3

After gathering equipment…Return to the patient. Before proceeding, check the 7 rights of medication administration

1. Right person – check the patient’s arm band against the name on the prescription. Where possible aim to use two identifiers (e.g. from the patient and the arm band)
2. Right drug – check the labelled drug against the prescription – ensure expiry date is appropriate
3. Right dose – check the dose against the prescription
4. Right time – confirm when the last dose was given
5. Right route – see below
6. Right to refuse – has the patient consented?
7. Right documentation of the prescription and allergies – does the patient have any allergies?

Once these have been confirmed prepare the medication. Always use a separate drawing up needle and injection needle.

Question 4

What are the steps of injection?

Answer 4

1. Wash hands
2. Don gloves and apron
3. Draw up the appropriate medication into the syringe using a drawing up needle.
4. Remove the drawing up needle and immediately dispose of it in the sharps bin, then attach the needle to be used for injection.
5. Choose an appropriate site, common sites include:

Deltoid (upper arm)
Ventrogluteal (upper outer buttock) – ideal for larger volumes
Vastus lateralis (anterior lateral thigh)
Do NOT use a site that is inflamed, irritated, bruised or contains scar tissue
See the end of the guide for further information regarding the most commonly used sites.

If multiple injections are given, use different sites for each subsequent injection. If frequent injections are given, rotate sites.

6. Position the patient to provide optimal access to your chosen site.
7. Cleaning the site:

When administering a vaccination the site does not need to be routinely cleaned prior to injection unless the skin is visibly soiled (in which case you would need to clean the site with soap and water). 4
There is some debate as to whether the skin should be cleaned with an alcohol wipe prior to administration of intramuscular medication, with WHO stating that cleaning is likely unnecessary. Many hospitals however still recommend routinely cleaning with an alcohol wipe to reduce the risk of hospital acquired infections, so you should adhere to your local medical school and hospital guidelines.
8. Gently place traction on the skin with your non-dominant hand away from the injection site, continuing the traction until the needle has been removed from the skin. This is known as the Z-track technique (see below). If the patient is elderly with reduced muscle mass or the patient is emaciated, do not apply traction, instead ensure that the muscle is ‘bunched up’ to ensure adequate bulk before injecting.

9. Warn the patient of a sharp scratch.
10. Holding the syringe like a dart in your dominant hand, pierce the skin at a 75 – 90 degree angle. Insert the needle quickly and firmly, with the bevel facing upwards, leaving approximately 1/3 of the shaft exposed (however this varies between sites and patients).
11. Aspirate to check the location of the needle:

If blood appears, remove the syringe and prepare a new injection (explaining the reason for this to the patient)
It is recommended that you aspirate when giving IM medications as these are often given via deeper IM injections which are associated with a higher risk of accidental administration into a vessel
If administering a vaccination via a shallow IM injection, UK guidance suggests there is no need to aspirate prior to injection of the vaccine 5
12. If no blood appears on aspiration inject the contents of the syringe while holding the barrel firmly. Inject the medication slowly at a rate of approximately 1ml every 10 seconds.

13. Remove the needle and immediately dispose of it appropriately (into a sharps container).
14. Release the traction on the skin.
15. Apply gentle pressure over the injection site with a cotton swab or gauze. Do NOT rub the site.
16. Replace gauze with a plaster.

Z – track technique – releasing the traction on the skin changes the alignment of the subcutaneous and muscle tissue layers, ‘locking’ the medication into the muscle layer.

Question 5

What do you do to complete an IM injection?

Answer 5

Thank the patient

Discuss post injection care:

Warn them that the injection site may be sore for one or two days, but this is normal.
Other potential complications include: haematoma, persistent nodules, local irritation (and rarely anaphylaxis).
Advise the patient to watch for a developing rash, breathing difficulty or other relevant concerning symptoms. They should discuss this with a doctor if concerned.
Wash hands

Document that the medication has been given on the medication chart and in the patient’s notes.

Question 6

How do you inject in a deltoid site?

Answer 6

Deltoid site
Position of patient

Have the patient sitting down, with their entire shoulder and arm exposed.
Position their elbow flexed and ask them to relax.
Site of injection

Palpate the lower edge of the acromial process and inject approximately 2.5cm below this.

Question 7

How do you inject in a ventrogluteal site?

Answer 7

In the past the dorsogluteal site was very popular, however due to potential complications such as sciatic nerve injury or superior gluteal artery injury it is now not recommended. Instead the ventrogluteal site is used as a safer alternative as it avoids all major nerves and blood vessels.

Position of patient

The patient can be prone, semi-prone or supine for this procedure, so choose whichever is most comfortable for the patient.
Site of injection

Place palm of your right hand over the greater trochanter of the patients left hip (or vice versa).
Extend your index finger to touch anterior superior iliac crest.
Then stretch your middle finger to form a V (thumb pointing towards the front of leg)
Insert the needle into the V at 90 ̊

Question 8

How do you calculate volumes for injections?

Answer 8

(Strength x volume of stock solution)/stock strength = volume required

Or
[What you want (prescribed) x volume]/what you have got = volume requried

https://radar.brookes.ac.uk/radar/file/d417f0d0-10e8-42ba-b66a-f4512495c11d/1/drug%20calculation/1_05.htm