Mlsp

• Pre-analytical considerations in phlebotomy

  • Patient preparation
  • Specimen collection
  • Specimen handling/transport
• Physiologic variables and their effect on laboratory tests

  Factors that can influence laboratory test results
• Physiologic variables


  • Age and gender
  • Altitude
  • Dehydration
  • Diet
  • Drug therapy
  • Exercise
  • Jaundice
  • Position
  • Smoking
  • Stress
• Age and gender


  RBC & WBC values are higher in newborns than adults

  RBC, hematocrit, & hemoglobin are higher in males than females
• Altitude


  RBC count is elevated at higher altitudes
• Dehydration


  Blood components become concentrated in the smaller plasma volume
• Diet


  Urea is elevated after high-protein diet

  Glucose is elevated after carbohydrate-rich meals

  Lipids may cause lipemic samples
• Drug therapy


  Blood cells can decrease due to chemotherapy drugs
• Exercise


  Lactic acid, potassium & skeletal muscle enzymes increase
• Jaundice


  Condition characterized by increased bilirubin in the blood

  May cause icteric (yellow turbid) samples
• Position


  Plasma volume decreases from supine to sitting up to standing up
• Smoking


  Increases cholesterol, glucose, and triglycerides level
• Stress


  Increases WBC due to emotional stress such as anxiety, fear, or trauma
• Problem sites for venipuncture

  • Difficult to palpate

  Newly burned areas-painful

  Healed burn areas-impaired circulation

  Tattooed area-impaired circulation and contain dyes
• Damaged veins


  • Sclerosed

  Thrombosed

  Cord-like

  Lack resiliency

  Occluded or obstructed
• Edema


  Veins are harder to locate

  May yield inaccurate results
• Hematoma


  Caused by leaking from a blood vessel during or following venipuncture

  Painful

  Hemolyzed sample
• Mastectomy


  Blood should never be drawn from an arm on the same side of mastectomy

  Lymphostasis
• Obesity


  Veins may be deep and difficult to find

  Penrose drain tubing, long Velcro strap, BP cuff can be used
• Arteriovenous shunt, fistula or graft


  Never apply tourniquet in an arm with fistula
• Intravenous (IV) site


  Turn off IV for at least 2 minutes

  Apply tourniquet distal to the IV

  Select venipuncture site distal to the IV

  Collect blood in a different vein than the one with the IV if possible

  Restart the IV

  Note on the requisition slip that the specimen was collected in an IV site
• Patient complications and conditions

  • Allergies to equipment and supplies

  Excessive bleeding

  Fainting

  Pain

  Petechiae
• Allergies to equipment and supplies

  Adhesive allergy - hold pressure for 5 minutes

  Antiseptic allergy - use alternate antiseptics

  Latex allergy - avoid physical contact with latex products
• Fainting


  Loss of consciousness, can last from a few seconds to half an hour

  Before, during, or after the procedure

  Patient should be monitored for at least 30 minutes after fainting
• What to do if patient faints

  Release the tourniquet and lower the patient's head

  Apply pressure to the site

  Talk to the patient

  Physically support the patient

  Apply a cold compress or wet washcloth to the forehead and back of the neck

  Document the incident according to facility protocol
• Pain


  Can range from small amount to marked or extreme

  May include numbness, burning, or electric shock sensation in the arm
• Petechiae


  Tiny, nonraised red spots

  Normal size is less than 3mm

  Does not mean the phlebotomist used incorrect procedure
• Procedural error risks


  • Hematoma

  Infection

  Nerve injury

  Reflux of additive
• Infection


  Do not open adhesive tape or bandages ahead of time

  Once the collection site is cleansed, do not contaminate it

  Open the needle cap once ready to extract blood

  Keep the bandage on for 15 minutes after specimen collection

  Do not preload needles onto tube holders unless ready to use them
• Nerve injury


  Can be caused by improper vein selection, needle too deep, patient movement, excessive redirection of the needle, or blind probing
• Reflux of additive


  Flow back into the patient's vein from the collection tube

  The contents of the collection tube are in contact with the needle while the specimen is being drawn
• Specimen quality concerns


  • Hemoconcentration

  Hemolysis

  Partially-filled tubes
• Hemoconcentration


  Increase in the fluid content of the blood

  Can be caused by prolonged tourniquet application, massaging the site, probing, hand pumping, or sclerosed/occluded veins
• Hemolysis


  Damaged red blood cells and their hemoglobin content escaping into the fluid portion

  Causes the sample to appear pink, dark pink to light red, or dark red
• Troubleshooting venipuncture issues


  • Failed venipuncture

  Needle not inserted far enough

  Needle bevel not far enough

  Needle bevel partially into the vein

  Needle bevel against the upper/lower vein wall

  Needle beside the vein

  Collapsed vein
• Failed venipuncture


  Can be caused by improper tube or needle position
• Needle not inserted far enough

  No blood flow at all

  Slowly advance the needle deeper
• Needle bevel not far enough


  Causes a hissing sound, superficial veins, retraction of tube, and a spurt of blood that then stops
• Needle bevel partially into the vein

  Causes impaired blood flow, hematoma, and requires gently pushing the needle further in
• Needle bevel against the upper/lower vein wall


  Causes impaired blood flow and requires adjusting the needle angle