Overview
This lecture provides step-by-step demonstrations and essential considerations for performing intradermal, subcutaneous, and intramuscular injections, including key techniques and safety protocols.
Intradermal Injections
- Typically performed on the forearm.
- Clean the site with an antiseptic swab from the center outward and allow to dry.
- Use a small gauge needle with the bevel facing up.
- Hold the syringe high and insert at a 5-15° angle, just under the skin.
- Inject medication to form a bleb (wheal/bubble) under the skin.
- Withdraw the needle at the same angle and do not massage the site afterward.
Subcutaneous Injections
- Suitable sites include the abdomen, backs of arms, and thighs.
- Clean the site in a circular motion and allow it to dry.
- Pinch up subcutaneous fat before injection.
- Insert at a 90° angle if ≥1 inch of fat, or 45° angle if less.
- Inject medication, release the pinch, and withdraw at the same angle.
- Dispose of the needle immediately and do not massage the site.
Intramuscular Injections
- Common site demonstrated: vastus lateralis (thigh).
- Locate site using anatomical landmarks: palm on greater trochanter, middle finger to iliac crest, index finger toward groin, forming a triangle.
- Clean site in concentric circles and allow to dry.
- Hold needle like a dart and pull the skin taut.
- Insert at a 90° angle into the muscle, inject medication slowly, and withdraw at the same angle.
- Immediately dispose of the needle in a sharps container.
Z-track Intramuscular Injection Method
- Displace upper tissue layers laterally using the side of the non-dominant hand.
- Clean site and prepare as with other IM injections.
- Inject at a 90° angle, inject medication, then withdraw needle and release tissue.
- Creates a zig-zag path to prevent medication leakage into other tissue or out of the wound.
- Use needle safety features as appropriate and dispose of immediately.
Key Terms & Definitions
- Bevel — The angled tip of a needle to facilitate entry into tissues.
- Bleb (Wheal) — Raised bump under the skin formed after an intradermal injection.
- Subcutaneous Tissue — Fatty layer beneath the skin where subcutaneous injections are administered.
- Intramuscular (IM) — Injection delivered directly into muscle tissue.
- Z-track Method — Injection technique that displaces skin and tissue to prevent medication leakage.
Action Items / Next Steps
- Practice each injection technique on appropriate models or under supervision.
- Review steps for site selection, needle angle, and disposal protocols.
- Study anatomical landmarks for IM injections.