Venipuncture and Blood Draw

Venipuncture is the procedure used to draw a blood sample from a patient or intravenous therapy through intravenous access. 

The procedure is usually performed by phlebotomists, medical technicians, nurses or laboratory scientist, but sometimes EMT’s, paramedics, dialysis technicians, medical practitioners or other trained medical staff.

Venipunctureis an invasive procedure routinely performed for one of two reasons. One is to procure blood for the purpose of diagnostic testing or to monitor levels of certain blood components. 

Blood analysis is one of the most used diagnostic tools in healthcare as the data are used to interpret a variety of clinical symptoms and signs.

Blood is typically taken from the vein called the median cubital. That vein lies close to the surface of the skin, in the cubital fossa anterior to the elbow. 

Micro mini quantities of blood can be collected by fingersticks, but for most blood drawing, venipuncture is the procedure of choice.

Venipuncture Procedure

The procedure for a venipuncture is simple. The area of the puncture is sanitized with antiseptic. 

The blood drawing specialist will wrap a restricting band type tourniquet around the upper part of the arm to be the subject of venipuncture that will apply the necessary pressure to make the vein fill with blood. The health care provider will slowly and carefully insert the needle into the vein.

The blood will collect in a vial that is airtight and attached to the needle. The vials are designed to draw a predetermined amount of blood for a specific type of blood analysis. 

After the appropriate amount of blood is taken, the restricting band will be removed from your arm and the puncture treated with an antiseptic and covered with a small gauze bandage to keep the puncture from bleeding and to keep it clean.

Following the blood draw, the needles and caps are disposed in an appropriate sharps container. Needles are never reused, recapped, broken or bent after the one time use. 

Rubber gloves will be worn by the person taking the blood sample and discarded in an appropriate container following the blood draw.

Preparation For A Venipuncture

The only preparation is to limit certain medications or to avoid food and drink prior to the procedure. Your Doctor will let you know ahead of time what preparation you may have to do. After the procedure you may experience some throbbing for a short time, but that will subside.

Veins vary in size from person to person and a venipuncture is more successful on some people than others. Other risks associated with a venipuncture include infection, hematoma, fainting or feeling light headed and excessive bleeding.

Venipuncture Technique And Tips

When drawing blood is a problem, there are a few troubleshooting hints that can be followed. First try repositioning the needle and if that does not work check the collection tube and make sure it is pushed completely back into the needle.

If the technician thinks the vacuum may be lost, try another needle. If that does not solve the problem, loosen the restricting band. The patient should never be stuck more than twice. If all else fails, call the supervisor.

Blood Draw

A blood draw is the process of removing blood samples form an individual for the purpose of testing. 

The process does not take a long time, but the time it does take depends on how accessible the veins are. If the subject’s veins are small, they may be hard to access, as well as, if the veins are not close to the skin surface, that may present some extraction challenges.

A blood draw is performed by a phlebotomist or other health care professional trained to take blood samples. Doctors who order blood tests for their patients will discourage the patient from eating any food prior to the test, but will allow the patient to drink water. 

The Doctor may also advise the patient to limit the intake of certain medications.

It is in the best interest of the patient to be well hydrated as the blood will flow more readily when the vein is punctured. 

A blood draw is usually taken from the median cubital vein that is usually located close to the skins surface and located near the elbow.

How To Draw Blood

The procedure to perform a blood draw is not complicated. The patient will be required to expose the back side of their arm which means rolling up a long shirt sleeve or taking their arm out of the sleeve altogether. 

The technician will swab the area of puncture with antiseptic. The blood draw specialist will wrap a tourniquet type band around the patients forearm in order to increase blood flow to the area of concern.

Once the vein is filled with blood, by visual observation, the technician will insert a small needle into the vein. 

A pressurized vial is connected to the needle and will collect the extracted blood. The vials are designed to take a predetermined amount of blood for the predetermined blood test.

After the necessary volume of blood is extracted, and most tests or series of tests require multiple vials to be filled, the tourniquet is removed from the patients arm. 

The technician will swab the area of the puncture with antiseptic and cover it with a small bandage to keep the puncture clean and from bleeding further.

Blood Draw Procedure

A blood draw is typically performed with a small, fine needle. The initial puncture may be uncomfortable, but the actual blood draw will not be painful. If the technician does not hold the needle still or if the puncture is made an angle, their nay be a little bit of discomfort involved. 

There are a few risks involved with a blood draw including infection, fainting or feeling light headed, hematoma and excessive bleeding.

When drawing blood is a problem there are few things that can be tried. The needle can be repositioned and the collection vial can be checked to make sure it is pushed completely back into the needle. 

If the vacuum has been lost, the technician will need to use a new needle. The technician can try loosening the tourniquet. The patient should never be stuck more than twice when taking blood.