Subcutaneous injection in horses

Prepare the following materials:

• A second person to restrain the patient
• Swab with disinfectant
• Syringe and cannula (ideally a black 22G cannula)
• Medication for application

^{Treatment of a heat stroke patient:}

^{By carefully moving the cannula within the tissue, you can check whether you are safely subcutaneous. Good mobility of the cannula within the puncture site is an indication of correct positioning in the subcutaneous fatty tissue.}

Subcutaneous injection sites are located on the horse's neck and chest. Firstly, the person helping fixes the horse with a halter and rope. The injection site is then disinfected with a swab.

Injection into the chest area
A skin fold is then formed at the level of the front chest muscles using the thumb, index finger and middle finger (Fig. 1). In the centre of the skin fold, the cannula can now be advanced in a ventral direction, i.e. pointing from above towards the floor. The ventral direction of insertion makes sense because the medication collects according to gravity and is then distributed, so that you would be working against gravity with a dorsal insertion direction. It also has the advantage that the medication is not injected directly into your face if you accidentally puncture the skin.

Injection into the neck area
Form a skin fold with your thumb, index finger and middle finger either in the centre or in the lower third of the neck (Fig. 2).

Tip:
It is important that the puncture site is 1 hand's breadth above the cervical spine and 1 hand's breadth below the mane ridge.

The cannula is also advanced into the tissue in the centre of the skin fold in a ventral direction.

Once the cannula is securely positioned, the skin fold can be released and the syringe attached. Before injecting the medication, you must always aspirate to ensure that you have not punctured a vessel with the cannula and that the medication does not enter the bloodstream directly. For larger quantities, aspirate several times to check the correct position of the cannula. After the injection, the cannula is removed from the subcutaneous tissue.

If a horse is injected subcutaneously several times, care must be taken to ensure that the same point is not always punctured. Therefore, make a note of the area and side you have used after the injection. A different site will then be used for the next injection.