Venipuncture Technique Using the Multisample Vacutainer™ System

Venipuncture Technique Using the Multisample Vacutainer™ System

Reprinted: With permission granted to Danni R. by Terry Kotrla MT(ASCP)BB

The Vacutainer™ system consists of a double-pointed needle, a plastic holder or adapter, and a series of vacuum tubes with rubber stoppers of various colors, the colors indicate the type of additive present. Another kind of holder is available, which allows reapplying the needle's sheath of the needle with the holder after venipuncture. Blood collection using the evacuated tube collection system produces the best blood samples for analysis by the laboratory. The patient's blood flows directly into the appropriate test tube.

Vacutainer™ Needle

The Vacutainer™ needle is pointed at both ends, with one end shorter than the other. The long end of the needle is used for insertion into the vein, the shorter end is used to pierce the rubber stopper of the vacuum tube and usually is covered by a rubber sheath. The sheath makes it possible to draw several tubes of blood by preventing leakage of blood as tubes are changed, this is called a multi-draw needle. If the short end is not covered with a rubber sheath, it is a single sample needle and only one tube of blood can be collected.

There are several sizes of Vacutainer™ needles available, the size depends on the length and gauge of the needle that goes into the vein. Vacutainer™ needle lengths range from 1 to 1 ½ inches. One inch needles are used for routine venipuncture, 1 ½ inch needles are used for patients with very deep veins. The gauge of a needle is a number that indicates the diameter of its lumen; the lumen, also called the bore, is the circular hollow space inside the needle.

The bigger the gauge, the smaller the lumen. The most frequently used gauges for phlebotomy are 20, 21 and 22. The bevel is the slanted opening at the end of the needle. the phlebotomist performs a venipuncture so that the bevel of the needle is facing upward when the needle is inserted into the vein. Vacutainer™ needles come in single use, sterile packages, either peel apart envelopes or plastic cases.

Vacutainer™ Holder

The Vacutainer™ holder is a plastic sleeve into which the phlebotomist screws the double pointed Vacutainer™ needle. Holders are available in two sizes, one for adult venipuncture and one for pediatric procedures. Some Vacutainer™ holders are single use, it covers the needle after use and the whole apparatus is disposed of. Most holders are used repeatedly and disinfected as necessary.

Vacutainer™ Tubes

Vacutainer™ tubes are glass tubes sealed with a partial vacuum inside by rubber stoppers. The air pressure inside the tube is negative, less than the normal environment. After inserting the longer needle into the vein, the phlebotomist pushes the tube into the holder so that the shorter needle pierces the stopper. The difference in pressure between the inside of the tube and the vein causes blood to fill the tube. The tubes are available in various sizes for adult and pediatric phlebotomies. Adult tubes have volumes of 5, 7, 10 and 15 mL and pediatric tubes are available in volumes of 2, 3 and 4 mL.

Trademark: Vacutainer is a federally and internationally registered trademark owned by BD (Becton, Dickinson and Company) that is used in connection with a complete system of tubes, needles and needle holders, sharps collectors, and safety devices. Reference: Becton Dickinson Trade Information # 109.

Blood Collection Step-by-Step Instructions:

Open needle package but do not remove needle shield - safety needles should be used!

Thread needle onto holder. If drawing sterile sample, use sterile holder/needle combination

Select tube or tubes appropriate for the type of sample

Tubes that contain additives should be gently tapped to dislodge any additive which may be trapped around the stopper

OSHA's recent ban on tube holder reuse dictates use of a NEW tube holder for every patient!

Insert tube into holder, then gently push tube so that the stopper is penetrated by the needle

Select site for venipuncture by viewing and palpating all available veins of both arms

Apply tourniquet. Prepare venipuncture site with an appropriate antiseptic. YOU MUST NOT PALPATE VENIPUNCTURE SITE AGAIN AFTER CLEANSING!

Secure patient's arm in a downward position that is stable but yet comfortable for the patient

Remove needle shield

Perform venipuncture

Push tube onto holder, puncturing diaphragm of stopper

Remove tourniquet as soon as blood appears in tube. Do not overfill the collection tube

If no blood flows into tube or ceases to flow before an adequate sample is collected, the following steps are suggested to complete satisfactory collection:

Confirm correct position of needle cannula in vein

If a multiple sample needle is being used, remove the tube and place a new tube into the holder

If the second tube does not draw, remove needle and discard in appropriate disposal device

Repeat procedure from Step 1

When first tube is adequately filled remove it from holder

Place succeeding tubes in holder (following correct order of draw), puncturing diaphragm to initiate flow. Tubes without additives are drawn before tubes with additives

While each successive tube is filling, invert the previous tube containing additives 8-10 times. DO NOT SHAKE!

As soon as blood stops flowing in the last tube, remove needle from vein

Activate the needle shield's safety feature, and discard

If conventional needles are used do not recap needle, bend, or shear.

Dispose needle straight into proper container!

Apply pressure to puncture site with dry, sterile swab, until bleeding stops

Apply bandage if desired, except in infants and toddlers

Proper precautions should be take when handling tubes to avoid contact with blood droplets

Dispose of any holder that becomes contaminated with blood

Additional resources on phlebotomy procedures, order of draw, etc.

visit the Internet Pathology Laboratory's Phlebotomy Procedure page!