Intradermal Techniques

Intradermal injections are a method of introducing a substance (allergen, vaccine or other) under the top layer of the skin. This method is used most often in tuberculosis screenings, also known as purified protein derivative, or PPD testing. Another common use for intradermal injection is allergen testing, where a small amount of suspected allergen is injected. Both PPD and allergen testing requires monitoring for a reaction. A flu vaccine that was approved in early 2009 for use in Europe also requires intradermal delivery.

Preparation

• Most substances used for intradermal injection are refrigerated prior to use. Allow the substance to warm to room temperature before injecting unless otherwise noted on packaging. Attach the needle to the syringe and draw up the substance to be injected. The most common needle used for intradermal injection is the 26 gauge. Lengths vary, but are generally 1/2 inch or smaller. Typically, a tuberculin syringe or 1 milliliter syringe is used. Other items you will need include a cotton ball or pad, alcohol wipes and gloves.

  Choose your site carefully. The site should be free from bruising, rash or other lesions. Intradermal injections can be performed at almost any subcutaneous site and also in the inner forearm and along the shoulder blades. Depending on the type and reason for the injection, there may be a required site. Check guidelines prior to performing injection.

Injection

• Wash hands with soap and water and put on gloves. Clean the area for the injection thoroughly with alcohol. Allow the alcohol to dry before performing the injection. Stabilize the skin around the injection site, but do not stretch or move the skin. Uncap the needle and position it with the bevel up. Insert the needle at a shallow angle, approximately 15 degrees. Just under the skin, you should feel some resistance. If not, the needle is likely too deep and should be pulled back until the bevel is barely under the skin. Press in the plunger injecting the substance. A wheal or bubble should appear at the injection site.

After Care

• Remove the needle at the same angle in which it was inserted. Using a cotton ball or pad, cover the area until any wound weeping stops but do not press or rub. Caution the patient to avoid rubbing the area. If this is an allergen test, the patient should remain close by and the site will need monitoring for reaction. Tuberculin tests are generally examined in 24 to 48 hours after administration.

Cautions

• It is possible to tear the skin during an intradermal injection. Keep the needle as steady as possible and caution the patient to remain still during administration.

  Monitor all patients for potential anaphylactic reaction to the substance being used. Note any rash, difficulty breathing, dizziness or swelling of the face or hands. Be prepared to treat anaphylaxis immediately.

  Always follow your organization's guidelines for the administration of medications. Verify the patient, substance expiration date and physician orders prior to administrating any medication.