A butterfly needle, formally known as a winged infusion set, is a specialized device used to deliver intravenous (IV) fluids or medications. It consists of a short, small-gauge needle connected to flexible tubing and two plastic wings for secure handling. The design allows for greater precision and less movement within the vein compared to traditional IV catheters. This makes it the preferred choice for patients with small, rolling, or fragile veins, such as pediatric or geriatric individuals, or for procedures requiring only a short-term infusion.
Preparing the Equipment and Patient
Administering an IV infusion begins with preparing both the supplies and the patient. Gather all necessary items, including the sterile butterfly needle set, the prescribed IV solution bag and tubing, and an antiseptic skin preparation (like chlorhexidine or povidone-iodine). Securing materials like transparent dressings and medical tape are also needed. Finally, ensure you have a tourniquet, a saline flush syringe, and a puncture-proof sharps container for safe disposal.
Selecting the appropriate needle gauge is important; gauges generally range from 21-gauge to 25-gauge. Smaller numbers indicate a larger diameter. A smaller gauge, like 25-gauge, is often selected for very fragile veins, while 23-gauge offers a good balance of flow and reduced trauma. Identify a suitable insertion site, typically a straight, visible vein in the hand or forearm. Cleanse the area using the antiseptic solution according to guidelines, allowing it to fully air dry.
Performing the Venipuncture
The first step in the venipuncture procedure is applying the tourniquet a few inches above the selected site to engorge the vein, making it prominent and stable. Ask the patient to clench their fist gently to aid in vein dilation. Use your non-dominant hand to anchor the vein by gently pulling the skin taut just below the intended insertion point. This stabilization helps prevent the vein from rolling away during insertion.
Hold the butterfly needle set by the plastic wings, gripping them between your thumb and index finger. Ensure the needle’s bevel—the slanted opening at the tip—is facing upward, as this orientation minimizes tissue damage upon entry. Approach the skin at a shallow angle, ideally between 10 and 15 degrees. Insert the needle smoothly and deliberately through the skin and into the vein lumen.
Successful cannulation is confirmed by observing a “flashback” of blood entering the clear plastic hub or the tubing connected to the needle. This indicates the needle tip has entered the vein. Once the flashback is seen, advance the needle slightly further, perhaps by a millimeter or two, to ensure the entire bevel is fully within the vessel and the tip is stable.
Maintaining a steady hand and minimizing patient movement is important for comfort and success. If the needle is inserted too steeply or moved excessively, it can puncture the back wall of the vein, leading to infiltration or hematoma formation. The flexible tubing attached to the butterfly needle allows the operator to maintain a comfortable distance from the insertion site, reducing the risk of accidental movement.
Securing the Infusion and Monitoring Flow
Once the needle is successfully positioned within the vein, release the tourniquet to restore normal blood flow. The line should then be flushed with a small amount of sterile saline solution to confirm patency and clear any residual blood from the needle and tubing. Observe the site for any signs of swelling or patient discomfort during the flush, which could indicate the needle is not correctly seated within the vein.
After confirming patency, connect the primary IV administration set or the extension tubing to the butterfly hub. Securing the entire setup prevents accidental dislodgement and subsequent vein trauma or infection. The wings of the butterfly needle should be laid flat against the skin and secured with a transparent semi-permeable dressing or sterile tape. Ensure the insertion site remains visible for ongoing inspection.
Secure the tubing itself using a loop or chevron taping method, creating a small loop near the insertion site before taping it down. This loop acts as a strain relief, absorbing accidental tugs on the line and preventing them from pulling directly on the needle. If using an infusion pump, program the device to the prescribed flow rate. If administering via gravity, adjust the roller clamp on the IV tubing to achieve the correct drip rate.
Closely monitor the patient immediately after initiating the infusion for any adverse reactions, such as pain, burning, or signs of infiltration like localized swelling or coolness at the site. Regular checks of the site and the infusion rate ensure the medication is delivered safely and effectively.
Safe Removal of the Butterfly Needle
Discontinuation of the IV infusion requires a systematic approach to minimize patient discomfort and bleeding. Begin by stopping the flow of the IV solution, either by closing the roller clamp on the tubing or by pausing the infusion pump. Carefully remove all securing tape and the transparent dressing from the skin, ensuring the needle remains stationary during this process.
Before withdrawing the needle, place a sterile gauze pad directly over the insertion site. Apply firm, direct pressure to the site while simultaneously removing the needle in one swift, smooth motion, pulling straight back along the line of insertion. Applying pressure before removal helps prevent blood from escaping the vein immediately upon withdrawal.
Immediately after the needle is completely out of the skin, activate the needle’s built-in safety retraction mechanism, if one is present, to shield the exposed sharp tip. This prevents accidental needlestick injuries to both the operator and the patient. The entire used butterfly needle set, including the attached tubing, must be promptly disposed of into an approved puncture-proof sharps container.
Continue to apply pressure to the venipuncture site for at least two to three minutes, or until bleeding has completely stopped. Once bleeding stops, cover the area with a small adhesive bandage. Advise the patient to keep the bandage in place for several hours and to monitor the site for any delayed bleeding, swelling, or signs of infection.