Venepuncture (Blood tests)
⚠️ Important: Never take blood from the arm with an arteriovenous (AV) fistula,
or from an arm that may need one for renal replacement, unless senior advice confirms it is safe.
👉 An AV fistula often feels like a gentle “cat purring” beneath the skin due to turbulent flow.
👋 Introduction
- 🧼 Wash hands and use appropriate PPE.
- Ensure your name badge is visible; introduce yourself clearly.
- ✅ Confirm correct patient identity (name, DOB, hospital number).
- Explain the procedure, why it is necessary, and obtain verbal consent.
🧰 Equipment
- Sterile gloves & apron.
- Tourniquet.
- Alcohol wipes / 2% chlorhexidine wipes.
- Green needle or vacutainer system, syringes, and appropriate blood bottles.
- Cotton wool/gauze and plaster or tape.
- Sharps bin.
💉 Technique
- Apply the tourniquet to the upper arm and allow veins to dilate.
- Select a suitable vein (usually forearm or antecubital fossa).
- Clean the site with alcohol wipes and avoid re-touching the skin.
- Insert the needle at ~30° angle – you may feel a “give” when entering the vein. Look for flashback.
- Attach vacutainer tubes/syringe and allow to fill to the correct volume.
- Release the tourniquet before removing the needle – failure to do so can cause bruising/haematoma.
- Remove the needle, apply pressure with gauze until haemostasis, then dress with plaster.
- Thank the patient.
😰 Difficult Venous Access
- If multiple attempts in forearm/antecubital fossa fail → pause, rehydrate patient, or ask a colleague.
- If urgent: femoral vein access may be considered.
👉 Lies medial to femoral artery at inguinal crease. Clean meticulously; use green needle/syringe at 90°.
- In IV drug users, veins may be scarred/thrombosed – patients may help identify usable sites.
✅ Aftercare & Safety
- Dispose of sharps immediately in correct bin.
- Label bottles at the bedside with patient identifiers (never pre-label).
- Document procedure and answer any patient questions.
⚠️ Complications
- Failure: After 2–3 failed attempts, seek help or return later.
- Haematoma: Commonly from not releasing tourniquet before removing needle. Apply pressure.
- Arterial puncture: Recognised by bright red pulsatile blood. Withdraw immediately and apply firm pressure.
📚 Teaching Pearls
- Always check which arm NOT to use (AV fistula, post-mastectomy, lymphoedema).
- Order of draw matters for certain tests – follow local guidelines.
- Good communication and reassurance reduce patient anxiety and improve success.
