Peripheral Intravenous Cannulae: Insertion and Maintenance

A peripheral intravenous (IV) cannula is a small, flexible tube inserted into a peripheral vein to provide access for the administration of fluids, medications, and blood products. As one of the most common invasive procedures performed in healthcare, proper technique is essential to ensure patient safety and reduce the risk of complications.

Indications and Preparation

IV cannulation is indicated for patients requiring intravenous therapy, including fluid resuscitation, continuous medication administration, or frequent blood sampling. Before the procedure, the clinician must confirm the order, gather all necessary equipment, and perform hand hygiene.

• Gather Equipment: Cannula of appropriate gauge, tourniquet, antiseptic wipes (chlorhexidine-based), sterile gauze, transparent dressing, IV fluid/giving set, and gloves.
• Patient Communication: Verify the patients identity, explain the procedure, and obtain verbal consent.
• Site Selection: Choose a vein that is visible, palpable, and free from infection or bruising. Start distally on the non-dominant arm whenever possible.

The Insertion Procedure

1. Apply Tourniquet: Place the tourniquet 510 cm above the insertion site to distend the vein.
2. Clean the Site: Clean the skin using an aseptic technique. Allow the antiseptic to air dry completely.
3. Venipuncture: Hold the cannula at a 1530 degree angle. Pierce the skin and enter the vein. Observe for "flashback" of blood in the hub.
4. Advance and Secure: Once blood appears, lower the angle and advance the cannula slightly. Slide the plastic catheter forward off the needle while withdrawing the needle. Remove the tourniquet, apply pressure above the site, and dispose of the needle in a sharps container.
5. Fixation: Attach a sterile transparent dressing to secure the cannula and allow for visual inspection of the site.

Maintenance and Monitoring

Routine maintenance is critical to prevent complications such as phlebitis, infiltration, and catheter-related bloodstream infections (CRBSI).

• Visual Inspection: The site should be assessed at least once per shift for signs of redness, swelling, tenderness, or leaking.
• Dressing Changes: Replace the dressing if it becomes damp, loose, or soiled.
• Flushing: Flush the cannula with normal saline before and after every medication administration to maintain patency.
• Documentation: Record the date, time, site, gauge, and the name of the clinician who performed the insertion.

Complications

Recognizing complications early is vital for patient safety:

• Phlebitis: Inflammation of the vein, often presenting as redness, pain, or a palpable cord. If present, the cannula should be removed immediately.
• Infiltration/Extravasation: Occurs when fluids leak into the surrounding tissue, causing swelling and coolness. Stop the infusion immediately.
• Infection: Systemic symptoms like fever or local signs like pus require urgent medical evaluation and removal of the device.

By adhering to evidence-based protocols regarding aseptic technique and regular site monitoring, healthcare providers can maximize the effectiveness of IV therapy while minimizing discomfort and risk to the patient.