SELECTING SITES
Antecubital area most often accessed
Hand or wrist
Remember: 2 arms
Use tip of index finger on non-dominant hand to palpate area to feel for the vein
COLLECTION SITE PROBLEMS
Indwelling lines:
Hickman catheters
Heparin locks
Used to administer medication
Only nurse may access these lines
Can obtain blood: called a ‘line draw’
Must clear line of heparin contamination by discarding first 5-10 cc of blood
5. Coagulation:
• In vivo
– Blood is fluid
– Clot is formed to
protect injured vessel
• In vitro
– Spontaneous reaction
– Triggered by glass or poor drawing technique
5
7. Blood with anticoagulant:
• Clotting is prevented
and irreversible
• Mix:
completely invert 8-10x
• Whole blood
• Centrifuge plasma
• Plasma contains
fibrinogen
7
8. Blood without
anticoagulant:
• Spontaneous clotting occurs
and is irreversible
• Fibrinogen fibrin strands
• Fibrin strands entrap cells
• Centrifuge serum
• Serum lacks fibrinogen
8
9. Appearance
• Normal: clear and ‘yellow’
• Abnormal:
– Hemolyzed = pink to red (ruptured RBC)
– Icteric = dark orange-yellow (bilirubin)
– Lipemic = cloudy (fat, triglycerides)
9
10. Blood Collection Tubes:
• Contain a vacuum
• Used with
Vacutainer and
Syringe systems
• Stoppers universal
color coded:
indicates contents
• Have an expiration
date
10
16. Blue-top tube:
• Anticoagulant = sodium citrate
• Binds calcium
• Must be full
Blood:anticoagulant ratio critical
• Must be on ice if not analyzed within 30 minutes
• Coagulation studies
16
PLASMA
Whole blood
17. Green-top tube:
• Anticoagulant = heparin
– Three formulations: Lithium heparin
Ammonium heparin
Sodium heparin
• Inhibits thrombin formation
• Must be full and on ice if need pH, ionized Ca
17
PLASMA
Whole
blood
18. Green-top tube:
• Most chemistry tests, STAT lab (PST)
Decreases time needed for blood to clot,
Makes turnaround time better
18
21. Fibrin-split Products tube
• Light blue top tube with 2 yellow bands on the
label
• Contains soya bean thrombin which causes
the blood to clot immediately
21
22. Yellow-top tube:
• ACD = acid citrate dextrose
– Paternity testing
– DNA
• SPS = sodium polyanethol sulfonate
– Used for special blood culture studies
– Inhibits certain antibiotics
• Both bind calcium
• PLASMA, Whole blood 22
23. Type and Amount of Specimen:
• Dependent upon
– Test
Whole blood: EDTA or heparin?
Plasma: EDTA or heparin?
Serum: trace free? Separator gel interference?
– Amount of sample needed to perform test
– Multiple labs needing the same specimen at the
same time 23
24. Valid Test Results Require:
• Trained personnel
– Causes of pre-analytical error
– Invalid test results
• Quality control
• Quality assurance
• Sophisticated
instruments
24
25. Safety Practices:
For infection to spread:
1. Infectious substance: HBV, HCV, HIV
2. Mode of transmission
3. Susceptible host
25
26. Modes of Transmission:
• Parenteral: any route other than the
digestive tract
– Intramuscular
– Intravenous
– Subcutaneous
– Mucosal
• Ingestion
26
Non-intact skin: chapped
hands, cuts, cuticles
Percutaneous: needles, sharps
Permucosal: mouth, nose, eyes
28. Safety: Infection Control
• Hand washing
– Primary means of preventing spread of
infection (especially nosocomial)
– Minimum 15 seconds, soap, friction
– Wash hands before and after each blood draw
• PPE
– Lab coat
– Gloves
– Mask
• Standard precautions at all times 28
30. Equipment:
4. Bandage, tape (use caution with children)
5. Sharps container:
– Discard needles,
lancets
– Biohazard marking
– Puncture resistant
– NEVER recap, bend
break needles
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31. Equipment:
6. Tourniquets:
– Slows venous blood flow down
– Causes veins to become more prominent
– NEVER leave on for >1 minute
– AVOID rigorous fist clenching or hand
pumping (potassium, lactic acid, LD)
– Latex allergy
31
33. Equipment:
7. Needles
– NEVER reuse a needle
– NEVER use if shield is broken
– NEVER recap, cut, bend or break
– Drop immediately into sharps container after
venipuncture
– Size of needle is indicated by gauge:
• Larger gauge number indicates smaller needle diameter
• 21, 23 gauge needles routinely used for phlebotomy
33
37. Butterfly Needle:
• Most often used with
syringe
• Expensive, thus not used
for routine draws
• Used for small, fragile
veins
• Increased risk of needle
stick injury
37
40. Labeling Blood Collection Tubes:
• Black indelible marker (water proof)
– Never pencil
– Legal document
– Print legibly
• Required information: 5 items
– Patient name
– Identification number
– Date of draw (mm,dd,yyyy)
– Time of draw (military time)
– Phlebotomist signature: first initial, last name40
41. Vacutainer or Syringe?
• Vacutainer
– Most often used
– Most economical
– Quick
– Least risk of accidental needle stick
• Syringe
– More control
– Reposition easily
– Will see ‘flash’ of blood in syringe hub when
vein successfully entered
41
42. The Patient:
• Approach
• Communication
• Empathy
• Handling special situations
• Patient identification
– Arm band
– Legal document
• Prepare patient for blood draw
– Latex allergy?
42
43. Selecting the Site:
• Antecubital area most
often accessed
• Hand or wrist
• Remember: 2 arms
• Use tip of index finger
on non-dominant
hand to palpate area
to feel for the vein
43
44. Collection Site Problems:
• Indwelling lines:
– Hickman catheters
– Heparin locks
• Used to administer medication
• Only nurse may access these lines
• Can obtain blood: called a ‘line draw’
• Must clear line of heparin contamination
by discarding first 5-10 cc of blood
44
45. Inserting the Needle:
• Anchor the vein
– Grasp arm with your
non-dominant hand
– Use thumb to pull skin
taut
• Smoothly and
confidently insert the
needle bevel up
– 15-30 degree angle
45
47. Fill Tubes:
• Use correct order of draw:
– Blood cultures
– Red top
– Blue (baby blue)
– Green
– Purple
– Grey
47
48. Be careful not to:
• Push needle further into vein when
engaging evacuated tube
• Pull needle out of vein when disengaging
tube
• Pull needle out of vein as you pull back on
the plunger
• Pull up or press down when needle in vein
• Forget to mix additive tubes 8-10 times
48
49. Withdraw Needle:
• First release tourniquet
• Disengage tube
• Place cotton directly over needle, without
pressing down
• Withdraw needle in swift, smooth motion
• Immediately apply pressure to wound
• Do not bend arm
49
50. Label Tubes Immediately:
• In sight of patient
• Patient name
• Identification number
• Date of draw
• Time of draw
(military time)
• Your initials
50
54. You should try again
• Look at alternate site
– Other arm
– Hand
• Use clean needle
• Use fresh syringe if
contaminated
• Only try twice
54
55. Poor Collection Techniques:
• Venous stasis
– Prolonged application of tourniquet (>1 min)
• Hemodilution
– Drawing above IV
– Short draw (blood to anticoagulant ratio)
• Hemolysis
– Traumatic stick
– Too vigorous mixing
– Alcohol still wet
– Using too small of needle
– Forcing blood into syringe 55
62. Skin Puncture:
• Method of choice for infants, children
under 1 year
• Adults
– Scarred
– Fragile veins
– Hardened veins
– Home glucose monitoring (POCT)
– Patients with IV
62
63. Capillary Blood
• Mixture of arterial, venous, capillary
blood and fluid from surrounding
tissues
• Fluid from surrounding tissues may
interfere and/or contaminate the
specimen
• Warming skin puncture site increases
arterial blood flow to the area
• Reference ranges often differ from
venous
63
64. Skin Puncture Equipment:
1. PPE
2. Cleaning agent
– Alcohol pads: routine
– Soap and water: alcohol testing,
allergies
– DO NOT use providone iodine
1. Cotton balls, gauze
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65. Skin Puncture Procedure:
1. Wash hands
2. Approaching the patient
3. Patient identification
4. Latex allergy?
5. Bedside manner
6. Site selection
7. Cleanse site: DO NOT use providone- idodine
8. Perform puncture: Wipe away first drop of blood
9. Label the specimen 68
66. Skin Puncture Procedure:
• Hold finger between your index finger and thumb
• Puncture the finger using a quick, smooth motion
• Wipe away the first drop of blood
69
67. Skin Puncture Procedure:
• Collect sample
– DO NOT touch collecting device to skin surface
– DO NOT scrape collecting device across skin surface
– DO NOT scoop blood into collecting device
70
68. Skin Puncture Procedure:
• Order of draw is critical: platelets
accumulate at puncture site causing clot
formation
– Blood smear
– EDTA
– Heparin
– Serum
• Apply pressure to puncture site
• Label specimen in sight of patient (indelible
marker)
71