Intravenous catheterisation of the horse.

The research sets out to provide comprehensive guidance on how to correctly perform intravenous catheterisation in horses. The procedure is useful for delivering large amounts of fluids, ensuring irritant drugs are injected safely, and allowing for the repeated collection of blood samples over extended periods. The jugular vein is the common site used for this.

Types of Catheters

• The most commonly used catheter is a combination of a metal trochar and plastic cannula. These catheters need to be suitably large to enable high flow rates and should measure at least 3 inches in length.
• An alternative system includes a flexible cannula inside the needle, which moves through the needle’s lumen into the jugular vein after venipuncture. These long cannulae enable the distal end to be positioned near the right atrium, allowing central venous pressure to be measured.

Catheter Insertion

The process for insertion of the catheter is outlined in the text. It stresses the criticality of performing the procedure in a sterile manner to prevent subcutaneous infections, jugular phlebitis, and thrombosis. The procedure involves:

• Firstly, preparing a shaved 10 cm square over the jugular furrow in the upper third of the horse’s neck.
• The site is then prepared as for a sterile operation and local anaesthetic is injected into the skin.
• Following the displacement of the anaesthetised skin away from the jugular vein, a small incision is made.
• The metal trochar and plastic cannula are then inserted into the skin incision and advanced into the vein.
• Subsequently, the metal trochar is held in place as the cannula is pushed over it into the vein until the Luer fitting is against the skin incision.
• The catheter is then flushed with heparinised saline and secured in position by a suture.
• Lastly, the site is bandaged and the catheter is regularly flushed to keep it open.
• Fluid administration sets are secured to prevent unnecessary traction on the catheter and tetanus antitoxin or toxoid is administered if necessary.

These guidelines are essential for ensuring the efficiency and safety of intravenous catheterisation in horses.