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The major risk of drawing blood or starting an IV is
Arteries, veins, & capillaries are the three main veins while drawing blood in arm
A butterfly needle with tube and vacuum syringe.
Another name for a winged infusion set is a "butterfly needle." This device consists of a hollow needle with two flexible "wings" on either side, which help secure the needle in place during venipuncture. Butterfly needles are commonly used for drawing blood or administering medications in small veins.
When drawing blood, the needle is typically inserted at a 15 to 30-degree angle for veins located close to the surface, such as in the antecubital fossa (the crease of the elbow). For deeper veins, a slightly higher angle may be appropriate, but generally, a 15 to 30-degree angle is ideal for most venipunctures. Proper technique helps ensure a successful draw while minimizing discomfort for the patient.
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A 21-gauge needle is commonly used for drawing blood for a chemistry profile. This size balances the need for sufficient blood flow while minimizing discomfort for the patient. However, a 22-gauge needle may also be used, depending on the patient's veins and specific laboratory requirements. Always ensure to follow your facility's protocols for blood draws.
Veins are the preferred choice for drawing blood samples because they are closer to the surface of the skin, making them easier to access. Additionally, veins have a larger diameter and are more elastic than arteries, which allows for a smoother and less painful blood draw process.
Capillaries are the microscopic blood vessels that connect small arteries to small veins. Blood exchange takes place in capillaries.
It is determined by the size of the veins
Blood draws normally occur through veins, though which blood moves slowly. There is low pressure and little muscular activity in the veins, resulting in lower pressure.
The butterfly venipuncture needle, also known as a winged infusion set, was invented by Dr. Richard M. Knapp in the 1940s. This design features plastic "wings" that facilitate easier handling and stabilization during venipuncture. It is widely used for drawing blood or administering medications, especially in patients with small veins or when a more delicate approach is needed.