What Are Butterfly Needles?

A butterfly needle is used by a medical professional to draw your blood from the vein or access a vein to give intravenous (IV) medications. It may be used to give infusion up to 100 mL saline in a child or an old person. An IV catheter is also used instead of butterfly catheters if the volume of fluid needed is more than 500 mL. It has a retractable needle that’s inside a protective sheath. The needle is inserted into the vein; the needle is removed, and the sheath or catheter is left in the vein. Whereas, with a butterfly needle, the needle is left in the vein instead of a plastic sheath. It is smaller in length than an IV catheter. Butterfly catheter is preferred over IV catheters in some cases, especially for drawing blood. Butterfly needles are manufactured in a variety of sizes. They’re measured by gauges. Most butterfly needles range from 18 to 27 gauge. The higher the number is, the smaller or thinner the needle size is.

The healthcare professional may use a butterfly needle while drawing blood for the following purposes:

• Venipuncture
• A venipuncture is when a phlebotomist accesses a vein to draw blood. A phlebotomist is a medical professional who specializes in drawing blood. Butterfly needles are useful to perform difficult venipunctures, such as on older adults, babies, children, or noncooperative patients. Butterfly needles are also often used when a person is donating blood. The needle has a flexible tube attached to the end, making it easy to connect to other tubes.
• IV hydration
• IV fluids may be administered using a butterfly needle in case of dehydration.
• IV medication
• A butterfly needle is used to administer IV medications.

Butterfly needles have a reduced rate of blood breaking down, reducing the risk of the blood sample damaged. Butterfly needles are better for those with bleeding disorders. Butterfly needles allow intravenous (IV) access using a small needle. This also reduces the risk of profuse bleeding, especially in those with bleeding disorders. It can often be used in babies who have blood vessels with a smaller diameter.

Butterfly needles involve leaving a needle in the vein, whereas the intravenous (IV) catheter is a thin, flexible catheter with no needle because the needle is removed. Leaving a needle in could cause injury to the vein and surrounding structures. A butterfly needle can typically not be used for more than 5-6 hours. A butterfly needle can sometimes be difficult to insert properly because the short needle may be easily pulled back from the vein, requiring re-injection.