While the majority of blood taking has been devolved to phlebotomists, nevertheless it is important for all appropriate healthcare individuals to be able to perform this useful skill, as phlebotomy rounds tend to be at fixed times, and sometimes blood results are needed rapidly.
Although you may initially wish to practice on a mannequin, your confidence will be improved by regularly performing venepuncture in the real world scenario.
As with any procedure, organisation and a clear structure are keys to success. Have all your equipment to hand before you attend the patient. If needs be, perform a mental checklist while gathering your supplies.
Approach the patient confidently and explain the reason for the procedure as well as obtaining consent. Verbal consent or the patient offering their arm is sufficient.
Successfully obtaining blood follows the law of diminishing returns, so if you don’t get it the first time, it is likely that subsequent attempts will be less fruitful, and both you and the patient will become more agitated.
Have the patient sat or lying down, so that if they feel faint, a fall and subsequent injury will be avoided. Identify a vein. Start at the antecubital fossa and work from there down to the hands. If the patient suggests a particular spot, listen to them. Make sure that there is enough light for you to see.
Apply a tourniquet to the arm, tight enough to impede venous return but not that tight that it hinders arterial flow or causes pain. If you are struggling, ask the patient to gently “pump” the arm. Other methods include hanging the hand down so gravity helps. You may wish to tap the vein, but do not slap it. This rarely helps and could be seen as assault.
Once you have identified the spot, make sure you use universal precautions. There is rarely a situation where it is not appropriate to wear gloves. Swab the area with an alcohol wipe so it is socially clean. There are two bloodletting systems; vacutainer and the older needle and syringe method. Try to become proficient in both.
Successful entry to a vein is sometimes felt as a “give” and a flashback into the vacutainer system. If this does not happen, gently manipulate the needle inside the vein, but do not withdraw outside of the vein and reintroduce with a tourniquet still on as this will cause haematoma.
If you are unsuccessful, most sources would advocate a maximum of three attempts, before abandoning and seeking help. Do not let your pride come in the way of asking for assistance.
Those sites to avoid include the same arm as a mastectomy or that affected by a CVA, or where there is any arterial or venous fistula. Try to make the procedure as easy as possible by identifying “good” veins and allowing them the time to fill up.
Always take the tourniquet off before you remove the needle. Apply pressure to the puncture site with a cotton wool or gauze. Check that the patient feels all right. Fill out the appropriate paperwork and labels, and if the bloods are needed in an emergency, make sure they are transported to the laboratory immediately.
Dr. Zak Uddin – Anniebarr.com Consultant