What is the procedure for inserting an intravenous (IV) cannula?

Procedure for Inserting an Intravenous (IV) Cannula

The proper insertion of an IV cannula requires careful preparation, appropriate site selection, and proper technique to minimize complications and ensure successful venous access.

Preparation

• Wash hands thoroughly and use clean gloves during the cannulation procedure to comply with infection control standards 1
• Select the smallest practical size of cannula for the intended purpose to minimize vein trauma 1
• Gather all necessary equipment before beginning the procedure 1
• Use needle guards when available to reduce needlestick injury risk 1

Site Selection

• Avoid insertion in limbs with lymphoedema except in acute situations due to increased infection risk 1
• The forearm and back of the hand are both suitable sites for peripheral cannulation, with no significant difference in complication rates 2
• Visually inspect and palpate potential sites to identify suitable veins before skin preparation 1
• Consider using transillumination, ultrasound, or infrared devices if venous access is difficult 1

Skin Preparation

1. Locate and palpate the intended cannulation site 1
2. Wash the access site using antibacterial soap or scrub (e.g., 2% chlorhexidine) and water 1
3. Cleanse the skin by applying 70% alcohol and/or 10% povidone iodine using a circular rubbing motion 1
   • Alcohol should be applied for 1 minute immediately prior to cannulation 1
   • If using povidone iodine, allow 2-3 minutes for full bacteriostatic action and let it dry before cannulation 1

Cannulation Technique

1. Apply a tourniquet to the access arm to enhance vein visibility 1
2. After disinfecting the site, pull the skin taut in the opposite direction of needle insertion to compress peripheral nerve endings 1
3. Insert the cannula at approximately a 25-degree angle for optimal entry 1
4. When blood flash is observed in the cannula chamber, flatten the angle of the needle parallel to the skin and advance slowly 1
5. When the cannula is in the vessel, remove the tourniquet and secure the cannula according to protocol 1
6. Assess for adequate blood flow by alternately aspirating and flushing with a syringe 1
7. Carefully assess for signs of infiltration (pain, swelling, discoloration) 1
8. Tape the cannula at the same angle or similar to the angle of insertion to maintain proper positioning 1

Post-Insertion Care

• Flush the cannula after use to maintain patency 1
• Monitor the site regularly for signs of complications 1
• Routine changes of peripheral cannulae at 72-96 hours is not advocated unless clinically indicated 1

Potential Complications and Prevention

• Infiltration/extravasation: Ensure proper cannula placement and secure fixation 1
• Phlebitis: Use proper aseptic technique and appropriate cannula size 1
• Infection: Maintain strict aseptic technique throughout the procedure 1
• Needle-related injuries: Use safety devices and proper disposal techniques 1

Special Considerations

• For difficult venous access, consider using a midline catheter (10-20 cm) inserted into upper arm veins under ultrasound guidance 1
• When removing the cannula, use the same or similar angle as insertion and never apply pressure before the needle is completely out to prevent vessel trauma 1