Venepuncture is the term used to describe the procedure of withdrawing blood from a vein using a needle.

Equipment

• Gloves
• Hand sanitiser
• Alcohol wipe
• Tourniquet
• Cotton wool/ gauze
• Needle
• Syringe or vacutainer
• Blood bottles
• Specimen bag
• Plaster or micropore tape
• Access to a sharps bin

Procedure

1. Introductions, check patient ID, consent, handwashing, check if the patient has any allergies (e.g. latex)
2. Apply tourniquet. Avoid an arm that has an intravenous infusion taking place as this may alter the results.
3. Locate vein (try to feel for a plump vein rather than look).
4. Wipe the area with an alcohol swab and allow to dry
5. Anchor the vein distally
6. Insert needle at a 30 degree angle or less, with the bevel facing upwards. Flashbak into the needle means the needle has entered the vein.
7. Attach bottles and fill, ensure you invert the bottle once filled to ensure adequate mixing
8. Remove tourniquet before removing the needle, applying pressure over the puncture site with cotton wool/ gauze
9. Apply plaster or tape
10. Label the bottles at the bedside and check patient wrist band!
    
    

Blood Cultures

Very similar to basic venepuncture, however it is imperative that you maintain an aseptic non-touch technique in order to not contaminate the sample and lead to a false result! This could lead to patients being erroneously treated or lead to the hospital getting fined.
Things to remember:

• Remove the cap off the top of each bottle and wipe with an alcohol swab allowing to dry. You will need 3 swabs in total (one each for the bottles, one for the patient).
• You must wear gloves.
• Each bottle needs at least 10 ml of blood added
• You must fill the aerobic bottle first (think about it the needle/ butterfly have air inside therefore use the aerobic bottle first!)
• Most blood culture bottles have a sticker on the side with a unique number, either make a note of this number or put the stickers in the patient notes so that they can be tracked if needed.
• Always document that you took the cultures with aseptic technique (or if this was not possible, why not) and the site
  • If a patient has a central line, take cultures peripherally and centrally

Bloods from central lines

Always check your hospital policy about using central lines (including PICC) to take blood samples as not all trusts accept this or may advise different methods. If in doubt, the nursing staff may be able to advise you as they have a breadth of experience!

1. Introductions, consent, hand washing, check ID.
2. Choose a port (without any infusions or if possible stop the infusion then take the blood sample >130 mins after this). Clamp the tube.
3. Put on gloves
4. If a neck line, ensure the patient’s head is turned away
5. Clean port with an alcohol swab for 15 seconds & allow to dry
6. Attach the syringe to the port and unclamp the tube. Withdraw 5-10 ml of blood & clamp tube.
7. Remove the syringe and discard this blood.
8. Attach a new syringe, release clamp, and withdraw the volume of blood needed for the blood sample, then clamp catheter. You can use a vacutainer at this point if you have compatible equipment
9. Attach a 10 ml 0.9% sodium chloride filled syringe. Release the clamp & flush with normal saline before re-clamping. Some trusts advise heparin flushes.
10. Give it another clean with an alcohol wipe and allow to dry.
11. Always re-attach any infusions you have stopped! Again, if in doubt ask the nurses to show you!

Further Reading

• Venepuncture video (thanks to Geeky Medics)
• Preventing blood culture contamination (thanks Rotherham NHS)

Written By Zana Martin (FY2)

Edited By Pratyush Pradeep (FY2)

Video created by Dr Cesci Adams, Dr Michaela Gaston, Dr Siona Sabu (Clinical Teaching Fellows)