TOPIC 3: TOURNIQUET TYING

• Tourniquet is used to assess and determine the location of a suitable vein for venipuncture
• It partially impedes venous blood flow back toward the heart and causes the blood to temporarily pool in the vein, making it more prominent and easier to obtain
• Types of tourniquet:

  • Rubber: may cause allergy
  • Latex free: preferred
  • Reusable: not much tension
  • Latex/rubber tubing: prone to slipping
• Antecubital fossa:

  • Shallow depression in the arm that is anterior to and below the bend of the elbow
  • First choice location for venipuncture
  • Major superficial veins at the antecubital fossa
• Basic Vein Arrangement:

  H Shape:

  • Composed of median cubital vein, cephalic vein, and basilic vein

  M Shape:

  • Composed of median vein, median cephalic vein, and median basilic vein
• Other Venipuncture sites:

  • Hand/Wrist: may be used when median cubital or cephalic veins are unsuitable or unavailable
  • Dorsal veins of the hand: include Basilic vein, Cephalic vein, and Dorsal venous complex
  • Veins on the underside of the wrist are never acceptable for venipuncture
  • Veins of the forearm are not ideal and veins of the foot are quite painful and more likely to be infected
• Vein Palpation:

  • A skilled phlebotomist relies more on touch or feel than on sight when determining a vein suitable for venipuncture
  • Palpation is used to assess the depth, width, direction, and health (resilience) of a vein
  • Use the index or middle finger to palpate the vein by aligning your finger in the direction of the vein, pressing on top of the vein with enough pressure to depress the skin, and keeping your finger in contact with the skin to feel the "bounce back" of a resilient, healthy vein
• "antecubital”– means in front of the elbow

  "fossa”- shallow depression
• H shape

  • 70% population
  • composed of median cubital vein, cephalic vein, basilic vein
• Median cubital vein (H shape)

  • at the center

  • preferred vein

  • larger and closer to the surface

  • better anchored

  • easiest and least painful to puncture
• Cephalic vein (H shape)

  • at lateral aspect

  • 2nd choice

  • harder to palpate than median vein

  • fairly well anchored

  • often only vein palpated in obese patients
• Basilic Vein (H Shape)

  • at medial aspect

  • last choice

  • easy to palpate

  • not well anchored

  • accidental puncture: medial cutaneous nerve or brachial artery

  • more painful punctures
• Median Vein (Intermediate Antebrachial Vein) (M Shape)

  • first choice

  • well anchored

  • less painful

  • not close to major nerves of arteries
• Median Cephalic Vein (Intermediate Cephalic Vein) (M shape)

  • 2nd choice

  • located away from major nerves or arteries

  • less likely to roll

  • relatively less painful
• Median Basilic Vein (Intermediate Basilic Vein)

  • last choice

  • appear more accessible

  • more painful

  • near anterior and posterior branches of the medial cutaneous nerve and brachial artery
• Veins of the foot

  • not ideal
  • quite painful
  • more likely to be infected (ex. phlebitis)
  • do not perform if patient is diabetic