Anatomy & Physiology
Diagram F – Anatomy of veins in hand and inner elbow
Diagram G – Anatomy of a vein
From the diagram above, the most common places for vein puncturing include the dorsal aspect of the hand and the cephalic vein in the forearm whereby success rates, pain level and complication rates are similar for both sites.
If having to use the cephalic vein, it is important to avoid the area of the anatomical snuffbox due to the increased risk of inadvertent puncture or cannulation of the distal radial artery.
If available, it is always best to target the larger looking veins that are easy to palpate.
Sites to avoid when performing cannulation include:
- Anatomical snuffbox
- Arms where there are arterio-venous fistulas (eg in dialysis patients)
- Areas where lymphatic drainage has been affected (eg the arm following axillary surgery)
- Areas of cellulitis or burns
- Small veins in the lower limbs and feet, especially in diabetic patients
- Areas of peripheral vascular disease, varicose veins, venous hypertension, or oedema
- Joint Surfaces
Veins and Veins to be Avoided
| Good Veins | Veins to Avoid |
| Bouncy | Hard |
| Soft | Thin/Fragile |
| Straight | Inflamed |
| Visible | Bruised |
| Well supported | Near to bony Prominences (painful) |
| Has a large lumen | Areas/sites of infection |
| Refills when depressed | Has undergone multiple previous punctures |
Preparation
An Aseptic technique should be used throughout procedure and all of the equipment below must be placed within a sterile phlebotomy tray with a sharps bin close by. You will also need to find a PRP kit for use. We use PRPHD by T:Lab. This has all of the tools inside for being able to approprietly take blood. It contains a butterfly needle in which to take the blood and vaccumed vials to catch the blood. You will also need:
- Gloves (and consider a plastic gown and protective eyewear and a facemask)
- Antiseptic wipes (2% chlorhexidine gluconate in 70% alcohol)
- Tourniquet (ideally disposable)
- Cotton wool swabs or gauze swabs
- Consider applying topical numbing for anxious clients
Prominent Venous Tips
- Make sure the limb is below the level of the heart
- Milking a vein from proximal to distal can make it appear more prominent
- Ask the patient to repeatedly make a fist with their hand
- Apply a gauze soaked in lukewarm water for two to three minutes
- Gently wipe the skin with an alcohol swab.
Ultrasound and handheld infrared devices can also be very useful to locate veins, where available.