WHY BEVEL UP WHEN DRAWING BLOOD

Everyone who has ever experienced the discomfort of a blood draw is familiar with the need for a sharp needle. Finding a vein for an injection can be a challenge on a restless patient, and any medical professional who performs blood draws knows that an angled needle is often more successful than a flat needle when it comes to finding the vein. If you've ever wondered why we bevel up when drawing blood, you are not alone. The answer has to do with the orientation of veins and the way blood flows through them.

Veins and Blood Flow

Our circulatory system is a complex network of vessels that transport blood throughout our bodies. Arteries carry blood away from the heart and contain oxygenated blood, while veins carry blood toward the heart and contain deoxygenated blood. Veins are generally thinner and less rigid than arteries, and they have valves that prevent blood from flowing backward.
When a medical professional draws blood, they are looking for a vein in which the blood is flowing in a downward direction. This is because gravity will help to pull the blood into the needle. Veins that are located in the arms or legs are often used for blood draws because they are easily accessible and have a downward blood flow.

The Beveled Needle

A beveled needle is a needle that has a sloped or slanted tip. This design makes it easier to puncture the skin and enter the vein. The bevel also helps to prevent the needle from cutting through the vein, which can cause pain and bruising.
When a beveled needle is inserted into the skin, the sharp edge of the bevel cuts through the skin and creates a small hole. The blood then flows into the needle through this hole. The angle of the bevel helps to guide the blood into the needle and prevents it from leaking out.

Why Bevel Up When Drawing Blood?

* By beveling up, the sharp edge of the needle is directed upward at a 10 – 30 degree angle when inserted into the skin, where the larger, deeper veins are located.
* The angle helps to keep the needle in place and prevent it from moving around while blood is being drawn.
* This also helps to prevent the needle from damaging the vein, which can cause pain and bruising.

Additional Tips for Successful Blood Draws

* Apply a warm compress to the area where the blood will be drawn. This helps to dilate the veins and make them easier to find.
* Have the patient drink plenty of fluids before the blood draw. This helps to hydrate the veins and make them more visible.
* Use a tourniquet to help fill the veins. A tourniquet should be applied just above the area where the blood will be drawn.

Conclusion

By understanding the anatomy of veins and the principles of blood flow, we can see why beveling up when drawing blood is the preferred method. This technique helps to ensure a successful blood draw with minimal pain and discomfort for the patient.

FAQs

1. Why is a beveled needle used for blood draws?

A beveled needle is used for blood draws because it is easier to insert into the skin and helps to prevent the needle from cutting through the vein.

2. What is the bevel angle of a blood draw needle?

The bevel angle of a blood draw needle is typically between 10 and 30 degrees.

3. What is the best location for a blood draw?

The best location for a blood draw is a vein in the arm or leg that is easily accessible and has a downward blood flow.

4. How can I make a blood draw less painful?

You can make a blood draw less painful by applying a warm compress to the area where the blood will be drawn, drinking plenty of fluids before the blood draw, and using a tourniquet to help fill the veins.

5. How can I prevent a bruise after a blood draw?

You can prevent a bruise after a blood draw by applying pressure to the area where the blood was drawn for a few minutes after the needle is removed.