Definition of Phlebotomy

Phlebotomy is the practice of using a needle to withdraw a sample of blood from a designated vein. In earlier times, phlebotomy was called bloodletting. It was used to treat and/or cure diseases. Phlebotomy today is also called venipuncture or venopuncture. A phlebotomist is a person who performs phlebotomy.

Venipuncture

• The most common site for venipuncture is at the median cubital vein at the antecubital site which is at the fold or bend of the elbow. Sterilization of the site of puncture with an alcohol swipe is necessary before the procedure.

  Each needle has a tunnel running through it to let blood flow through it. Each needle has a beveled point which is held upside down when inserted into a vein for the bloodletting.

  Sometimes a syringe is attached to the end of the needle and is used to fill up with blood. The more popular way of drawing blood is with the use of a vacuum tube or evacuated tube. A vacuum tube or evacuated tube is inserted through the other end of the needle to collect the blood. Each tube uses a vacuum mechanism to draw out blood.

  Gauze and bandages must be readily available to restore clotting and prevent bruising at the puncture site.

Sizes and Ways

• There are different sized needles for different sized patients and for different situations. Fingersticks are tiny needles used to stick one of the four fingers; usually, this is done to get a glucose measurement in cases of hyperglycemia or hypoglycemia. Fingersticks are also often used to draw blood from children.

  The smallest needle, the butterfly needle, is used most commonly for infants. This needle is also used for patients with small, hard to find veins. Infants are also given neonatal heel pricks. Since the antecubital spot is so small on an infant, a larger spot with more fat and liable to cause less pain to the infant is chosen to take a blood sample.

Transfusion

• Phlebotomists also obtain blood from people so that patients with large losses of blood can receive blood by transfusion. People who have been in major accidents, who have diseases such as hemophilia, who have abnormal menstrual flow or who are pregnant all benefit from the practice of phlebotomy.

Lab Tests

• Phlebotomists also take samples of blood to send to lab scientists and technicians.
  Lab technicians study the blood to find the anomaly and cause of certain diseases, such as, cardiovascular disease, artherosclerosis, hemophilia or AIDS. The results of blood tests enable doctors to diagnose and treat disease.

Forensic Testing

• Another field of phlebotomy is forensics, where criminal pathologists examine the blood of crime victims to determine the exact cause of injury and/or death. Phlebotomists also are given the task of insuring that all blood samples are guarded safely against contamination and/or tampering.