Theory and Rationale
The evacuation method is not always the best choice for performing venipuncture. The needle and syringe method is often used when very small or fragile veins are involved. The vacuum created when the collection tube is pressed over the needle point can cause damage to the tissue or collapse of the vein. The size of the syringe will vary according to the amount of blood needed. Usually a 10 to 20 ml syringe is used when several vacutainer tubes are needed. Ensure that venous specimen is immediately transferred to appropriate vacutainer tubes using a syringe adaptor.
- sterile needle (21- or 22-gauge)
- 10 to 20 ml syringe and syringe adaptor to transfer to vacutainer tubes
- phlebotomy tray or individual items (antiseptic or alcohol pads, appropriate vacutainers, sterile gauze)
- handwritten or preprinted specimen labels
- disposable gloves
- sharps container
- nonallergic tape or bandage
(Conditions) With the necessary materials, you will be able to (Task) demonstrate a venipuncture using the syringe method (Standards) correctly within 15 minutes.
- Review the physician’s order. Verify that the order is legible, includes a diagnosis and other necessary information, and is signed by the physician or his or her assigned person.
- Wash your hands.
- Prepare the laboratory requisition from the physician’s order.
- Identify the patient and escort him or her to the designated area.
- Verify that the patient has been properly prepared.
- Position and reassure the patient.
- Wash your hands again and put on disposable gloves.
- Insert the needle into the syringe.Move the plunger within the barrel to check movement.
- Apply the tourniquet.Wrap it around the patient’s upper arm 3 to 4 inches above the antecubital fossa (Figure 32-23). Cross the ends of the tourniquet and pull them snugly against the patient’s arm. With your thumb and forefinger, hold the tourniquet in place while pulling a loop of one end behind the joined area.
- Select the venipuncture site.
- Ask the patient to make a fist.
- Palpate the antecubital area with your index finger to determine the exact vein location and needle entry site (Figure 32-24).
- Clean the antecubital area (or other selected site) with an antiseptic or alcohol wipe (Figure 32-25).
- Allow the site to air dry, or dry it with a clean gauze pad.
- Hold the syringe with your dominant hand. Remove the plastic protective cover from the needle.
- To perform venipuncture:
- Make sure the patient’s arm is in a downward position to prevent reflux or backflow.
- Use your thumb to draw the skin taut to anchor the vein.
- Line the needle bevel up with the vein.
- With a single, direct puncture, enter the vein at a 15- to 30-degree angle (Figure 32-26).
- Observe for a “flash” of blood in the hub of the syringe.
- Have the patient release his or her fist.
- Slowly pull back the plunger of the syringe (Figure 32-27). Be certain that you do not move the needle after entering the vein. Fill the barrel to the needed volume.
- Release the tourniquet when you have obtained the appropriate volume and venipuncture is complete (Figure 32-28).
- Immediately place a sterile gauze pad over the site and withdraw the needle from the patient’s arm (Figure 32-29).
- Apply pressure or instruct the patient to apply pressure on the puncture site with sterile gauze.
- Transfer the blood immediately to the required tube(s) using the syringe adaptor. Invert the tubes after the addition of the blood.
- Discard the syringe in an approved container.
- Use the preprinted labels or label each tube with the patient’s first and last name, identification number (if applicable), date and time of collection, and your initials.
- Check the venipuncture site to make sure bleeding has stopped, then bandage it. Instruct the patient to leave the bandage on for at least 15 minutes (Figure 32-30).
- Remove and dispose of gloves.
- Wash your hands.
- Evaluate the patient for signs of faintness or color loss.
- Complete the laboratory requisition form and route the specimen to the proper place.
- Record the procedure in the patient’s chart.
Instruct the patient beforehand of the general procedure. Do not promise the patient that the procedure will not hurt. It is more tactful to say that it may feel like a brief “sting.” Let the patient know when the actual puncture is about to happen to avoid movement. As necessary, provide information about how long the results will take and how they will be transmitted to the patient.
Sometimes charting may not be required for phlebotomy procedures because laboratory processing documentation is sufficient. If charting is required, it might look like this:
6/8/XX 8:50 a.m. Pt appears calm but states that she has been told that she has small and fragile veins. General instructions given before each step. Venous specimen obtained using needle and syringe method. Obtained 15 ml of venous specimen and transferred to appropriate tubes. Pt. held pressure gauze on site, site bandaged, and pt. instructed to leave bandage in place for 15 minutes. Pt. escorted to waiting area. Maria Hernandez, CMA (AAMA)