Steps Involved in Phlebotomy
As a phlebotomy technician, you are expected to perform a lot of things, not just in drawing blood. Although collecting blood sample is your primary function, your role extends to the social aspect of phlebotomy. Even if your training doesn’t include ideas on how to properly interact with patients, depending on the course program you enrolled in, it is important that you get extensive knowledge about this particular aspect. Just think; if you were the patient and the phlebotomy technician wasn’t the least courteous or friendly, you probably would not have anything to do with him.
What are the best practices in phlebotomy, then?
The entire procedure is simply described in the flowchart below from CNACertification.com
- Prepare the equipment required
Whatever you need to perform a particular procedure must be within safe and easy reach from you, but away from your patient to keep stuff from being tipped over accidentally. Ideally a phlebotomy tray must have the following:
- Supply of laboratory sample tubes (sterile glass or plastic tubes) with rubber caps, vacuum-extraction tubes, or glass tubes with screw caps
- Sterile glass or bleeding pack, depending on the amount of blood to be collected
- Blood-sampling devices of different sizes
- Alcohol hand rub
- Gauze to be applied over the puncture site
- 70% alcohol swab to disinfect the skin
- Leak-proof transportation containers or bags
- Puncture-resistant sharps container for used needles
On top of these, there should be laboratory forms, specimen labels and pens that you will need.
- Patient identification and preparation
Now that you have the tools you need, it’s time to deal with the patient. The process differs when you are dealing with an adult (conscious) and a child.
- When patient is an adult:
- Make sure to introduce yourself and have the patient state their full name. For in-patients, check the arm band for verification. When working with outpatients, be sure to verify that the patient information matches what is written on the requisition form.
- Ask about allergies, phobias or instances when a patient fainted during blood collection. If the patients seem afraid or anxious, reassure them, ask about what will make them comfortable and let them know that only a minimum amount of blood will be drawn for testing. That is, if this is all you need.
- Make sure the patient fully understands the procedure before you proceed. Obtain verbal consent, as they have the right to refuse after they have been informed about the procedure.
- When patient is a child or a baby:
- Verify identification based on wrist or foot band attached to the patient.
- When a parent or guardian is present, ask the person for the first and last names of the child.
- Match the identity of the patient with that of the name, date of birth, and file number written on the laboratory form.
- Perform hand cleansing and put on gloves
- Before carrying out phlebotomy, technicians must wash their hands with soap and water and then dry with a single-use towel. An alternative would be to cleanse the hands with 3 ml of alcohol rub, starting with the palm of the hand, rubbing it into the fingertips and all over the hands until the alcohol dries out.
- Put on well-fitting latex, rubber or vinyl gloves. Make sure to ask if patient if allergic to latex, before you put on one.
- Select the venipuncture site
- Extend the patient’s arm so that the shoulder to wrist forms a straight line.
- Locate a vein that is visible, straight, clear and with a good size. The most frequently used veins are the larger median cubital, cephalic and basilica veins.
Image Credit: Pinterest/Cynthia Villareal
But once the patient clenches his fist, other veins will become prominent. Make sure that the vein you pick is already visible even before you apply the tourniquet.
- Apply the tourniquet 3-4 inches above the collection site or 4-5 finger widths, and then re-examine the vein. Don’t leave the tourniquet on for more than a minute. If you need more time to locate a vein, release it after 1 minute and then re-apply after 2 minutes.
In choosing a collection site…
- Avoid areas with extensive healed burns or scarring
- When a patient has had a mastectomy, don’t obtain blood from the arm that is on the same side as the breast that has been surgically removed.
- Avoid areas of hematoma
- Never obtain blood samples above the IV site, it should always be below
- Avoid an arm having a vascular, fistula or cannula graft
- Following a transfusion, wait 10 to 15 minutes before obtaining blood samples.
- Disinfect the collection site
- Clean the site with a swab soaked with 70% alcohol for 30 seconds, then allow it to dry.
- When applying the swab, use firm but gentle pressure and cover an area of 2 cm or more. Start from the centre and then moving downward or outwards.
- Make sure the site is completely dry before performing phlebotomy to avoid contamination.
- Perform venipuncture
- Anchor the vein using the thumb of your opposite hand and place it about an inch below the collection site. Make sure the bevel of the needle is pointing up, and then insert the needle with a quick, small thrust to penetrate the skin at no more than 150.
- As soon as blood flow is established, remove the tourniquet and ask the patient to unclench or open his hand. It is also important to note how long the tourniquet should be left on. Once sufficient amount of blood has been collected, carefully remove the needle.
- Have a clean gauze or cotton wool ready before you withdraw the needle. Gently withdraw the needle and then place the cotton or gauze over the puncture site with gentle pressure.
- Ask the patient to hold the cotton wool in place with the arm extended and raised. Remind them not to bend the arm to avoid hematoma.
Do not perform a venipuncture more than twice. If you don’t succeed at the first two attempts, inform a patient’s physician or your supervisor. Venipuncture should never be done on an artery and should not be performed on the feet unless specified.
Here’s a diagram for the entire Venipuncture process from Anatomical Blueprints2.
Phlebotomy procedure when using a syringe is basically the same as the one outlined above, except that blood is drawn by slowly pulling back on the syringe stopper, rather than an evacuated vacutainer tube. The process is also different when done on an infant or child because of the differences in the collection site and equipment that will be used.
- Collecting blood using multiple tubes
When multiple tubes are needed, the proper order of draw must be followed to avoid cross contamination and erroneous results. The recommended order below is set by the Clinical and Laboratory Standards Institute™ (formerly known as United States National Committee Clinical Laboratory Standards).
- Blood culture bottles, vials or sterile tubes
- Coagulation tube (light blue top)
- Clot activator (red top)
Serum separator tube (red-grey tiger or gold top)
- Tubes with royal blue tops are used mainly for nutritional studies, toxicology, and trace metal analysis
- Tubes with red tops are used for serology, chemistry tests and Blood Bank testing
- Sodium heparin (dark green top)
- PST (light green)
- EDTA (purple top)
- Blood tube (pale yellow top)
- Oxalate/fluoride (light grey top)
Never shake the blood vigorously, but invert them so that additives will be mixed. For most additives, inverting 4 times will suffice, while others require 8 to 10 times, or as specified by the laboratory.
Afterwards, prepare the samples for testing or transportation, and clean up any spills of blood or other body fluids.