Venipuncture

• Venipuncture


  The process of obtaining intravenous access for the purpose of intravenous therapy or for blood sampling of venous blood
• Venipuncture

  • It is essential to follow a standard procedure for the collection of blood specimen to get the accurate laboratory results
  • Any kind of error in collection of blood or filing the test tubes may lead erroneous laboratory results
• Professionals who perform venipuncture

  • Medical laboratory scientist
  • Medical practitioner
  • Phlebotomist
  • Nursing staff
• Appropriate venipuncture site


  Varies depending on the patient
• Venipuncture site

  • The site to check first is the upper bend of the arm
  • The primary vein used in the upper arm is the median cubital vein, usually the prominent vein in the middle of the bend arm
  • The basilic, cephalic, or median veins can be used as the second alternative
  • The median cubital and cephalic veins are most commonly used for venipuncture
  • Alternative sites are the basilic vein on the dorsum of the arm or dorsal hand veins
  • Due to its close proximity to the brachial artery and median nerve, the basilic vein, which is located on the pinkie side of the arm, should be used only if there is no other more prominent arm vein
  • Veins in the foot and ankle should be utilized only as a last resort
  • Veins on the underside of the wrist should be avoided
• Sites to avoid:

  
  

  Extensive scarring from burns or surgery

  Edematous arms

  The upper extremity on the side that a mastectomy was performed.

  
  

  A venipuncture should not be performed on a hematoma, regardless of how small it may be. If there is not an alternate vein to draw, the venipuncture should be performed distal to (below) the hematoma. Intravenous therapy/Blood Transfusions – If it is not possible to draw the opposite arm, then blood should be drawn from BELOW (distal to) the IV.
• • The tourniquet should be applied between the IV site and the venipuncture site.

   

  • If drawing above the IV site is the only option, then the IV infusion must be turned off for at least 2 minutes before performing the venipuncture.
• Procedure:

   

  1.      Wear appropriate personal protective equipment.

   

  2.      Prepare venipuncture equipment.

   

  3.      Select the best puncture site (antecubital fossa/back of the hand/wrist/ankle or foot).
• Position the patient's arm

  Slightly bent in a downward position
• Tourniquet application

  Applying a tourniquet to the patient's arm
• Place the tourniquet

  1. 3 to 4 inches above the selected puncture site

  2. Not too tight and not too loose
• Cross the tourniquet over the patient's arm

  1. Tuck a portion of the left side under the right side to make partial loop facing the puncture site

  2. The free end should be away from the puncture area

  3. Make sure there are no folds when applying the tourniquet
• 4.      Position the patient’s arm slightly bent in a downward position.

   

  5.      Tourniquet application.

   

  6.      Place the tourniquet 3 to 4 inches above the selected puncture site. (Application of tourniquet near the puncture site may cause the vein to collapse)

  7.      Cross the tourniquet over the patient’s arm. (Not too tight and not too loose)

   
• 8.      Tuck a portion of the left side under the right side to make partial loop facing the puncture site. The free end should be away from the puncture area. Make sure there are no folds when applying the tourniquet.

  NOTE: Tourniquet should only be applied not more than 1 minute. (prolonged application can cause hemoconcentration and hemolysis to the specimen)

  9.      Ask the patient to make a fist. This makes the vein more palpable. (Never ask the patient to “pump” the fist because this will cause hemoconcentration)

   
• 10.      Palpate the vein using the tip of the index finger or middle fingers in a vertical and horizontal direction to determine the depth, direction, and size of the vein.

  
  

  NOTE: The Basilic vein should be avoided if possible. (near the brachial artery and major nerves)

  
  

  11..      Release the tourniquet and have the patient open his/her fist. (No need to release if you can locate, palpate and extract within 1 minute)

  
  

  12.      Cleanse the area with 70% alcohol in a circular motion from the center to the outside.

  
  

  13. Allow the area to dry.