Activity 3

• Venipuncture


  process of accessing intravenous flow for the purpose of therapy or obtaining venous blood for sampling
• 1. Patient to make a fist, but not pump hands:
  2. make a fist for veins to be more prominent
  3. not pumping to prevent hemoconcentration
  4. Tourniquet:
  5. makes vein easier to feel or palpate
  6. 3-4 inches above intended puncture site
  7. must not be applied more than 1 minute
• the patient should be either lying down or sitting in a special phlebotomy chair
• phlebotomy chair


  has a movable arm support that helps in positioning the patient's arm
• Never attempt phlebotomy when a patient is standing
• If only armless chair is available, place patient arm on the his or her thigh for proper support
• Supine position is the most common phlebotomy position in inpatient in hospital beds
• H pattern


  ~70% of the population
• median cubital vein


  near center
• cephalic vein


  lateral aspect of the af
• basilic vein


  medial aspect of the af
• m pattern


  forms when cephalic and basilic veins divide into two branches forming v-shape
• median vein


  at the very center of the pattern
• median cephalic vein


  branches from the median vein to the lateral aspect of the arm
• median basilic vein


  branches from the median vein to the medial aspect of the arm
• tourniquet application

  1. position the tourniquet under the arm while grasping the ends above the arm and venipuncture area. the tourniquet should bet 3-4 inches above the site.
  2. cross the left and over the right end and apply a small amount of tension to the tourniquet.
  3. using the right middle finger or index finger, tuck the left and under the right end.
  4. a loose end of the tourniquet will be pointing toward the shoulder and the loop will be pointed toward the hand.
• palpating the venipuncture site

  • Determine size, depth, and direction of the vein
  • Palpate using the tip of the index finger
  • Select vein that is large, and does not roll from side-to-side or move easily
  • An appropriate vein for venipuncture will bounce and have resilience to it
  • Avoid veins that exhibit sclerosis, or feels hard and cordlike
• petechiae


  small, nonraised red spots in the skin due to a minute hemorrhage, can result if tourniquet is left on too long
• choking precautions


  patients should not be drinking, eating, or chewing gum during phlebotomy
• hematoma


  mass of blood caused by leakage of blood into the tissues (tourniquet is left too long, or left after needle is taken out; bevel went through and through the vein)
• hemoconcentration


  rapid increase in the ration of blood components to plasma
• specimen considerations: Avoid the following sites for venipuncture:

  edematous or full of swelling, iv site, mastectomy site (lyphostasis)
• Special considerations for various population groups:

  children, geriatric, patients with hiv or hepatitis, psychiatric patients