A Guide to Different Blood Draw Needle Types
People use medical needles millions of times every day across the world. Besides blood draws, the instruments are central to administering treatments and vaccines. In fact, their use is so important to medical interventions that, when the first COVID-19 vaccine rolled out, many countries experienced severe needle and syringe shortages that led to other health risks.
Like many other medical devices, there are different blood draw needle types. Each one is designed with specific procedures in mind. Understanding these distinctions can increase performance and procedure success rates.
This article covers the basics of venipuncture and the different blood draw needle types available. It also covers the distinct uses and advantages of each. Keep reading to learn more.
What Is Venipuncture?
Human beings have been drawing blood for thousands of years. There is documentation indicating that ancient Egyptians–then later the Greeks and Romans–employed medical techniques that involved draining human blood (“bloodletting”). It was not until the end of the 19th century that this practice was disproven as medically useful.
Since that time, advances in venipuncture have led to incalculable medical breakthroughs. It is the use of a needle to puncture a person’s vein.
The technique is used for multiple medical purposes today. These include drawing blood for testing (phlebotomy), administering therapeutic treatments, and collecting blood for later use (like transfusion).
Venipuncture requires specific training in different procedures and the use of equipment. This includes site selection, cleaning, needle insertion and removal, and post-procedure care for the patient. It also involves the preparation and use of equipment, including different blood draw needle types.
Main Blood Draw Needle Types
There are several different types of needles used for blood draws. Here are the main ones to consider.
Hypodermic Needle
A hypodermic needle is the technical name for a common needle (often generically to include the syringe). The needle is a hollow metal tube that attaches to a plastic hub. Most hypodermic needles are made of stainless steel.
Hypodermic needles come in a range of sizes. For most adult patients, a 21-gauge needle is appropriate. Sometimes nurses and technicians might use thinner needles for patients with smaller veins, such as children.
Hypodermic needles are used for many different types of medical procedures. While they are most often used in injections, they can also be used for blood draws. It is a quick and easy way to access blood from veins, although there are advantages to using alternative types and configurations for specific circumstances.
Butterfly Needle
A butterfly needle has two short plastic wings on the side. This helps promote handling and increased stabilization.
Butterfly needles are often smaller (22- or 23-gauge) than the standard 21-gauge needle. A “winged infusion” set is very similar to a butterfly needle. The difference is that it typically has longer tubing.
One of the main advantages of butterfly needles is that they allow for a shallower insertion pattern. This greatly reduces the risk of vein damage. It also makes the incision less painful than other kinds of needles.
These attributes make butterfly needles particularly useful in patients with hard-to-access, fragile, or superficial veins. They are often the go-to needle for children or elderly people. They also are commonly used in administering medications using an IV.
For the same reasons, butterfly needles are often used to access veins in harder-to-reach areas of the body. These include the scalp, hands, and feet.
One drawback to butterfly needles is slower blood collection. This can be enough of a deficit to make butterfly needles prohibited in certain procedures, such as emergencies. Also, like standard hypodermic needles, butterfly needles are “open systems” for blood collection.
Vacutainer Needle
A vacutainer needle is double-ended and includes a vacuum tube system. One needle is inserted into the vein, while the other protrudes from the vacuum tube barrel. A blood collection tube is then inserted into a barrel and punctured by the needle.
One advantage of this setup is that it allows for the collection of numerous blood samples with a single venipuncture. This is extremely helpful for blood draws, where many tests need to be done. Vacutainer needles also are prevalent at blood donation drives.
Another advantage is that since different-sized tubes can be used, these systems are ideal for getting more precise draws.
Vacuum tube setups are “closed systems.” This reduces exposure to contaminants and increases the integrity of the blood sample. It also keeps staff from having to come into contact with the blood.
Arterial Blood Gas Needle
In most cases, venipuncture involves accessing blood from veins. In some instances, arterial blood sampling is necessary.
As the name suggests, this is most often to check oxygen and carbon dioxide levels in blood flowing away from the heart. It can be used to check other things, like acid levels in blood flowing through arteries.
Although standard 20- to 22-gauge needles can be used in arterial blood gas draws, often much thinner needles (23- to 25-gauge) are preferable. This is to reduce pain. Also, the test usually only requires a small sampling, so blood flow rate is not an issue.
Lancet
A lancet is a needle, but it is distinct in that is not hollow. Lancets are designed to make small incisions in capillaries for blood draws. Other instruments, such as diabetes test strips or capillary collection tubes, are then used to collect the blood. This method of blood draw method is obviously “open,” so it is only used when testing blood for contents that are not affected by contaminants in the air.
Learn More About Blood Draw Needle Types
Now that you understand the different blood draw needle types, you can determine which is best for your practice or procedure. With so many options available for different applications, learning to use a wide range of blood draw needles is an asset for any healthcare provider.
At Precision Labs we are dedicated to offering our clients convenient, flexible options. We empower patients and their doctors with customizable schedules and accurate lab results. Reach out to us today to learn more.