When to use syringes instead of evacuated tubes during a phlebotomy procedure

When to use syringes instead of evacuated tubes during a phlebotomy procedure
March 26, 2013 Phlebotomy Training Group

Throughout the process of collecting blood, phlebotomy technicians must take reasonable measures when deciding which piece of equipment to use.


Although phlebotomy technicians use standard equipment, such professionals must always decide which tool is best to use in any given situation. This decision concerns the use of evacuated tubes or the use of syringes. The result will vary based on the characteristics of each patient.

The Use of Syringes or Evacuated Tubes

SyringeWhen a phlebotomist makes the usual choice to use an evacuated tube system to collect blood, it is based on the patient’s age and health in addition to the stability and size of the vein to be punctured. For individuals who are healthy and exhibit veins that are elastic, of good size and steady, the use of an evacuated tube system is recommended. If, however, patients exhibit challenging veins, those that are extremely small, fragile or unstable, the use of such tubes would not be appropriate. Attempting to collect blood from challenging veins could lead to undesirable results. This is especially true if an evacuated tube is used. As such, this may include the collection of too little blood or none at all. This may be due to a collapsed vein or the rolling nature of these veins. Veins of such individuals could also blow during a venipuncture procedure.

A blown vein is the term used for a vein that has been punctured too deeply. It is also associated with veins that have been punctured in another site other than the intended wall of the median cubital vein. A blown vein could result in the collection of blood in the surrounding tissue of such vein. This is known as a hematoma. It could also result in hemolysis: A breakage of red blood cells. These cells are needed in order to perform accurate diagnostic testing procedures.

Blown veins could also result from the pressure exerted upon them from the vacuum of an evacuated tube. This pressure is created when an evacuated tube is punctured. When punctured, blood is forcefully drawn into this tube. In this situation, a phlebotomist does not have control concerning the rate at which blood is collected. With challenging veins, the pressure or force of such vacuum may be too great. As such, this could cause a vein to collapse, hemolyze or result in a hematoma.

With individuals who present challenging veins, a syringe may be the tool of choice. The use of such a phlebotomy tool could result in a positive phlebotomy experience. As such, a phlebotomist will have the means necessary to control the rate at which blood is collected from a patient. This is done by adjusting the plunger of the syringe in accordance with the rate at which a phlebotomist wants blood withdrawn. Additionally, a blown vein is less likely to occur as a syringe will not create an automatic pressure system. Such system is characterized by evacuated tubes.

Syringes: The Elderly and Pediatric

Syringes are best used with patients who are of the elderly or pediatric population. In the elderly population, many of these individuals experience a loss of elasticity in the skin as this organ continues to mature with age. In such instances, it may be difficult for a phlebotomist to stabilize a rolling vein and collect the quantity of blood necessary for diagnostic testing. With a syringe, this task may be easily completed as a phlebotomist has some control concerning the quantity of blood to be withdrawn. In instances with rolling veins, a phlebotomist can stop and restart the blood withdrawing process based upon the stability of the vein. This can be done without a second phlebotomy procedure. A syringe can also be used to withdraw blood from infants as they have extremely thin veins that may require blood to be collected in increments.

Oncology Patients and Syringes

Oncology patients also benefit from the use of syringes during phlebotomy procedures. In oncology patients, use of this medical equipment helps with the ease of collecting blood. When oncology patients undergo chemotherapy, their veins may become diminished or lose its elasticity. As the veins of these patients may be difficult to stabilize, a syringe should be used to collected blood in increments.

Burn Victims and Syringes

Burn Victims and SyringesAs collecting blood from burn victims may also present a challenge, a syringe may prove to be beneficial. With such patients, it may be difficult to find a vein due to the presence and thickness of scar tissue. Thick scar tissue may present a challenge as it may restrict veins. Therefore, the flow of blood will also be restricted. With such patients, the use of a syringe will allow a phlebotomist to increase or decrease the withdrawal of blood as necessary. This is done by the adjustment of the plunger: The adjustable end of a syringe.

With the use of a syringe, phlebotomists can obtain blood from challenging veins that may present themselves in some patients. In deciding to use a syringe versus an evacuated tube system, a phlebotomist must make this decision based upon his or her training and experience. The average, young, healthy patient may require the use of the commonly used evacuated tube system for withdrawing blood. Those, however, who have veins that show any characteristics of a challenge, may require the use of a syringe. This method allows for flexibility and a controlled system that could result in an easy and desired venipuncture procedure for all involved.

Comment (1)

  1. Javier Campos 8 years ago

    Im not agree to use syringes in difficult patients, Such as children or elderly people, you can use a wingset or butterfly with a low vacuum tube , you have different sizes and volumens of tubes, CLSI in document A5- H5 recommend to use the correct device to do phlebotomy, I know syringes are use to collect the samples, but the syringes were made to introduce a liquid, needles to draw blood are differents, the internal diameter is bigger than a hypodermic needle. Even 75% of hemolysis occur when you use a syringe because you do not control the vacuum applied to collect the sample. Even you can be exposure to a needle stick injure using a syringe. Nowadays there new solutions in the market to collect a good quality sample without using a syringe

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