Venepuncture is marked on patient identification, aseptic technique and sharps safety rather than on speed. The World Health Organization asks you to clean the site with a 70% alcohol swab for 30 seconds and let it dry, not to touch the cleaned skin again, and to release the tourniquet before the needle comes out.
Key takeaways
- WHO guidance is to clean the entry site with a 70% alcohol swab for 30 seconds and allow it to dry completely for 30 seconds.
- Do not place a finger over the vein to guide the needle after cleaning, because that recontaminates the site.
- Release the tourniquet before withdrawing the needle, and always before it has been on for two minutes.
- Never recap a used needle; discard it directly into a puncture-resistant sharps container.
- NHS England recommends two sets of blood cultures, two aerobic and two anaerobic bottles, at 8 to 10 mL per bottle in suspected sepsis.
What is the examiner marking at the venepuncture station?
The Intercollegiate blueprint runs two procedural stations and marks them differently. A procedural skills station with a patient carries 8 marks for clinical and technical skill and 4 each for clinical knowledge, communication and professionalism. A technical procedural station, performed on a model rather than a person, carries 12 for skill and 8 for knowledge, with no communication or professionalism marks available.
Prepare for the version with a patient, because it is the harder of the two: the same technique has to be delivered while consenting, explaining and keeping the patient comfortable, and those marks are gone if you work in silence.
The examiner is marking the safety steps: identification, consent, hand hygiene, gloves, skin preparation, sharps disposal and labelling. Getting blood is assumed.
Talk through each step as you do it, including the ones a mannequin cannot show, so the examiner can award the mark.
What are the indications and contraindications?
Venepuncture is indicated for diagnostic blood sampling, monitoring, group and save, crossmatch and blood cultures.
- Avoid an arm with a fistula, lymphoedema, or on the side of an axillary node clearance
- Avoid sampling from above an intravenous infusion, which dilutes the sample
- Take care with cellulitis, burns or damaged skin at the intended site
- Check anticoagulation and any bleeding disorder, then apply pressure for longer
How do you take consent for venepuncture?
Explain what you propose to do, why, and what it will feel like, then obtain verbal consent and check understanding.
Royal College of Surgeons of England notes that since the Supreme Court ruling in Montgomery, doctors must take reasonable steps to ensure patients are aware of the risks material to them, so mention bruising, pain and the small risk of a repeat attempt.
What equipment do you need?
- Tray or trolley, cleaned, with everything within reach
- Tourniquet, 70% alcohol swabs, gauze and tape or a plaster
- Needle and syringe or a vacuum system, with appropriate tubes for the tests requested
- Blood culture bottles if indicated, plus a separate cleaning step for the bottle tops
- Non-sterile gloves, apron, eye protection where splash risk exists, and a sharps container at the point of use
What are the steps, in order?
- Wash your hands, introduce yourself and confirm the patient's identity against the wristband and the request form
- Check allergies, anticoagulants and any previous difficulty, and gain verbal consent
- Position the arm supported and extended, and inspect the antecubital fossa; WHO notes the median cubital vein is usually the easiest to puncture and that an artery and nerve run under the basilic vein
- Perform hand hygiene and put on gloves and apron
- Apply the tourniquet, palpate the vein, then clean the skin with a 70% alcohol swab for 30 seconds and allow 30 seconds to dry
- Do not re-palpate the cleaned site; insert the needle bevel up along the line of the vein and watch for flashback
- Fill the tubes in the order your laboratory specifies, to avoid additive cross-contamination
- Release the tourniquet, then withdraw the needle and apply pressure with gauze, asking the patient to keep the arm straight
- Dispose of the needle directly into the sharps container without recapping, then apply a dressing
- Label the tubes at the bedside with the patient's details and the date and time, then remove gloves and wash your hands
How do you keep venepuncture aseptic and safe?
Aseptic technique here is about the skin, the equipment and the sharp. **Asepsis** is the practice of ensuring that only uncontaminated equipment and fluids touch a susceptible site, as NICE defines it in CG139.
- Hand decontamination before and after every patient contact, as NICE CG139 requires
- Single use only for tourniquets where possible; WHO reports up to 25% of tourniquets are contaminated with meticillin-resistant Staphylococcus aureus
- Allow the alcohol to dry, because inadequate contact time increases contamination
- Bring the sharps container to the patient rather than walking with an exposed needle
How should blood cultures be taken?
Treat blood cultures as a separate, stricter procedure. NHS England's 2022 national review recommends two sets, meaning two aerobic and two anaerobic bottles, from a patient with suspected sepsis.
Each bottle should receive 8 to 10 mL, and at least 40 mL should be cultured from an adult, because yield rises by approximately 3% for every additional millilitre cultured.
What are the complications, and the common mistakes?
- Pain, bruising and haematoma, worse if the tourniquet stays on or pressure is inadequate
- Arterial puncture or nerve injury, which is why WHO warns about the basilic vein
- Needlestick injury to staff, and sample contamination from re-palpating the site
- Haemolysis and inaccurate results from excessive suction or the wrong tube order
- The classic station errors are not checking identity, touching the cleaned skin, recapping the needle, and labelling away from the bedside
How do you finish and document?
Check the patient is comfortable, dispose of waste, wash your hands, and confirm the sample is labelled and the request is complete.
Document who took the sample, from where, at what time, and any difficulty, then say you would follow up the result yourself.
The MRCS Part B Questions bank has a venepuncture station at /Sample-Questions.