Venipuncture

• Venipuncture is the most frequently performed procedure in phlebotomy
• Phlebotomy is the general term for blood collection, including venipuncture, capillary puncture, and arterial puncture
• All phlebotomy procedures start with the receipt of a test requisition form handed by nurses or doctors
• Requisitions must contain basic information like the patient's location, the number and type of collection tubes, and the status of the sample
• Patient preparation for venipuncture includes explaining the procedure, positioning the patient conveniently and safely, and checking for latex allergies
• Gloves should be worn during a venipuncture procedure, and the initial tourniquet application should last only 1 minute to avoid hemoconcentration
• The preferred site for venipuncture is the antecubital fossa, with veins like the median, cephalic, and basilic veins commonly used
• The median cephalic vein is preferred for venipuncture due to its size, stability, and less painful nature
• The cephalic vein is the second choice for venipuncture, located on the lateral aspect and easily felt in obese patients
• The basilic vein, located on the medial side, is not well anchored and has a high risk of accidental arterial puncture and nerve injury
• Other sites for venipuncture include leg, ankle, and foot veins, but usage requires permission from the patient's physician
• Cleansing the site for venipuncture involves using 70% isopropyl alcohol and making concentric circles around the site
• Before performing venipuncture, equipment should be checked for defects, needle and syringe properly assembled, and extra tubes readily available
• During venipuncture, it is important to re-apply the tourniquet first, examine the needle with the bevel up, and anchor the vein properly
• Equipment needed for a venipuncture procedure includes:

  • Requisition form
  • Gloves (latex and non-latex)
  • Tourniquet (latex and non-latex)
  • 70% isopropyl alcohol pad
  • Syringe needle (syringes and needles)
  • Evacuated tubes
  • 2x2 gauze
  • Sharps container (portable for out-patients)
  • Indelible pen (for manual labelling, notes, or refusal of patients)
  • Bandage
  • Biohazard bag
• Procedure for a venipuncture:

  1. Obtain and examine the requisition form, ensuring clarity if barcoded and completeness if manual.

  2. Greet and reassure the patient, explaining the procedure.

  3. Verbally identify the patient and compare information on the ID band with the requisition form.

  4. Verify fasting, latex allergies, or previous venipuncture issues.

  5. Select correct tubes and equipment, having extras available.

  6. Wash hands and wear gloves.

  7. Position the patient's arm for optimal blood flow.

  8. Apply the tourniquet correctly.

  9. Clean the site with alcohol and allow it to dry.

  10. Assemble equipment while the site dries.

  11. Inspect the needle and prepare for insertion.

  12. Anchor the vein and insert the needle smoothly.

  13. Collect the appropriate amount of blood.

  14. Release the tourniquet and remove the needle.

  15. Cover the puncture site and apply pressure.

  16. Discard the needle in the sharps container.

  17. Fill tubes in the correct order and mix anticoagulated tubes.
• 18. Label tubes and confirm identification with the patient.

  19. Examine the puncture site and apply a bandage.

  20. Remove gloves and wash hands.
• The tourniquet serves two functions:

  • Impedes venous blood flow, causing blood to accumulate in the veins making them more easily located
  • Provides a larger amount of blood for collection
• M pattern for venipuncture offers 2 choices of the median vein, while the H pattern offers 1 choice of the median vein
• Most patients have the H pattern, accounting for 70% of cases
• To determine if a patient has an H pattern or an M pattern, palpate the vein
• Steps for performing venipuncture:

  1. Re-apply tourniquet first

  2. Examine needle – BEVEL UP

  3. Anchor vein

  4. Insert needle at a 30-40 degree angle

  5. Fill tubes

  6. Remove needle

  7. Remove tourniquet

  8. Label tubes

  9. Bandage patient's arm

  10. Dispose of used supplies

  11. Check patient's well-being before leaving
• Complications and pre-examination variables for venipuncture:

  • Sleeping patients should be gently awakened
  • Unconscious patients should be greeted as conscious ones
  • Seek assistance for unavailable patients
  • Identify young and cognitively impaired patients
  • Collect blood from patients in a basal state
• Complications during venipuncture:

  • Fainting (syncope) can occur due to insufficient blood flow to the brain
  • Signs include paleness, hyperventilation, lightheadedness, dizziness, nausea, and clammy skin
  • Remedy includes lowering the patient's head between legs and giving spirit of ammonia
• Reasons for failure of blood to enter the syringe:

  • Excessive pull of the plunger
  • Going through the vein to the musculature
  • Very small angle of entry
• Hemoconcentration or venous stasis:

  • Increase in formed elements in blood due to decreased plasma volume
  • Follow specific time limits for tourniquet application
• Seizures during venipuncture:

  • Remove tourniquet and needle, apply pressure, and seek help
  • Restrain the patient to prevent injury
  • Document the seizure time according to policy
• Delayed local complications of venipuncture:

  • Thrombosis of veins
  • Thrombophlebitis
  • Hematomas
• Areas to avoid during venipuncture:

  • Damaged veins
  • Hematomas
  • Edema
  • Burns, scars, and tattoos
  • Arm on the same side of a mastectomy
  • IV therapy sites
• Common difficulties encountered during blood collection and processing:

  • Hemolysis: avoid due to various reasons like invalidating determinations and interfering with chemical analyses
  • Lipemia or lactescence: caused by chylomicrons, interferes with chemical analyses
• BASAL STATE

  • The ideal time to collect blood from a patient:
  • Refrained from strenuous exercise
  • Has not ingested food or beverages except water for 12 hours
  • The patient did not change position for 10-15 mins.
• PETECHIAE:

  • Small, non-raised red hemorrhagic spots that appear immediately
  • May result in prolonged bleeding following venipuncture
  • Patients with platelet disorders are common to this
  • Apply additional pressure to the puncture site after needle removal
  • Expect bruising later on and avoid hematoma
• VOMITING:

  • If the patient is nauseated, instruct them to breathe deeply and slowly; apply cold compresses to the forehead
  • If the patient vomits, stop blood collection and provide an emesis basin or wastebasket with tissues
  • Notify the patient's nurse or designated first aid personnel
• NERVE INJURY:

  • May lead to loss of movement in the arm or hand
  • Permanent injury in the venipuncture procedure can damage the median antebrachial cutaneous nerve
  • Signs include shooting pain, electric-like tingling or numbness running up or down the arm or in the fingers
• Delayed Local Complications: Thrombosis of Veins

  • Formation of blood clots inside the lumen of the vein due to trauma
• Delayed Local Complications: Thrombophlebitis

  • Inflammation of the vein caused by a thrombus
• Delayed Local Complications: Hematomas

  • Blue or black skin discoloration commonly due to repeated trauma or puncture of the veins
  • Most common one
  • If the needle penetrates through the vein
  • The vein is fragile
  • Fishing through the patient’s vein
• Phlebotomy Collection Tray:

  • Tool-like containers containing equipment necessary for venipuncture, dermal puncture, and arterial puncture
  • Compact containers like baskets meant for transport by medical technologists or phlebotomists in hospitals
  • Sometimes called a warding box or warding tray
  • Includes:
  • Sharps container
  • Disinfectants
  • Tourniquets
  • Scissors
  • Different types and sizes of evacuation tubes
  • Alcohol pads
  • Sample needles
  • Adaptors for needles
  • Syringes
  • Organization is crucial when going to a patient's ward with the tray
• Phlebotomy Drawing Station:

  • Features a reclining phlebotomy chair for outpatients
  • Organizer near the chair for tools and equipment storage
  • Large sharp container at the back
  • Includes a blood pressure cuff
• Evacuated Tube System:

  • Different from a syringe as blood collected by the needle is immediately placed in the tube
  • Safety Shield covers the needle after use to protect the patient from sharp injury