1. Apply a deflated pressure cuff to the upper arm about 6 cm above the elbow. Raise the pressure to between 60 and 80 mm Hg to enable the veins to be seen and felt. Select a large well situated vein for the venepuncture, usually near the bend of the elbow.
2. Clean very well the required part of the arm with cotton wool and 70% ethanol (alcohol). Wipe dry with a clean swab of cotton wool.
3. Take a blood collecting pack:
- Make a loose knot (without kinks) in the tubing. When sealing clips are available, there is no need to make a knot in the tubing.
- Suspend the bag on a stand (linked to a Balance) about 30 cm below the level of the donor’s arm.
- Clamp the tubing near to the needle guard. Whenever possible use plastic forceps to avoid damaging the tubing.
4. Make a venipuncture with the needle directed upwards in the line of the vein. Unclamp the tubing to allow the blood to flow. If necessary, secure the needle in place with a small strip of adhesive tape.
5. When the blood begins to flow, reduce the pressure of the cuff to 40–60 mm Hg, and ask the donor to squeeze slowly a small object.
6. When the blood enters the pack, gently mix it with the anticoagulant by lifting and tilting the bag. Do not squeeze the bag because this can damage the red cells. Mix the blood a further three times during the donation and when the donation is finished.
7. When the pack weighs 500–600g, the donation is complete, i.e. 450–495 ml blood has been collected.
8. Reduce the pressure in the pressure cuff to zero and remove the object from the donor’s hand. Clamp off the tubing 10–15 cm from the needle.
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