Methods of Blood Collection

Question 1

What are the two methods of blood collection?

Answer 1

• Capillary Puncture

- Venipuncture method

Question 2

What is Capillary Puncture?

Answer 2

• Method of blood collection by skin puncture
• Method of choice in pediatric patients
• Useful in adults with extreme obesity, severe burns, and thrombotic tendencies

Question 3

What site is capillary puncture collected?

Answer 3

• Distal phalanx of middle of ring finger
• Middle finder is first choice
• Can also be heel, finger, earlobe, or toe

Question 4

What is the best method of collecting blood?

Answer 4

Venipuncture

- Relative ease makes it a primary source of specimen

Question 5

What is the equipment necessary for Capillary puncture?

Answer 5

• Sterile gauze pads
• 70% ETOH or Betadine solution
• Lancet
• Capillary tubes or QBCstar
• Bandage

Question 6

What is the procedure for capillary puncture?

Answer 6

• Arrange equipment
• Wash hands
• Identify, greet, reassure Pt
• Educate Pt
• Massage finger towards fingertip
• Clean fingertip
• Stab using lancet
• Wipe away first drop of blood
• Obtain specimen
• Apply bandage

Question 7

How many times do you “massage” the finger in preparation for Capillary Puncture?

Answer 7

5-6 times

Question 8

When using the Lancet, what do you keep in mind?

Answer 8

• Max depth of lancet should be 2 mm

- Use lancet against the grains of the fingerprint

Question 9

Why do you wipe away the first drop of blood when performing capillary puncture?

Answer 9

Avoid dilution of the sample with tissue fluid

Question 10

When obtaining a specimen via capillary puncture, what angle do you want to hold the tube from the finger?

Answer 10

15 degrees

Question 11

How do you want to fill the tube when performing capillary puncture?

Answer 11

• Place tube at 15 degrees
• Keep tube in contact to avoid air bubbles
• Fill tube according to manufactures directions

Question 12

When performing venipuncture, what sites do you not want to use and why?

Answer 12

• IV sites

It can dilute the specimen or alter test results

Question 13

What is the equipment associated with venipuncture?

Answer 13

• Sterile gauze pads
• 70% ETOH/betadine solution
• Tourniquet
• Vacutainer needle
• Vacutainer holder
• Vacutainer tubes

Question 14

What is the procedure for venipunture?

Answer 14

• Position the Pt
• Have Pt sitting/lying
• Use caution so Pt does not fall from chair
• Wash hands
• Assemble equipment
• Identify, great, assure Pt
• Explain procedure
• Apply tourniquet 2-3” above site
• Palpate site
• Clean site
• Perform venipuncture

Question 15

Detailed needle stick portion of venipunture

Answer 15

• Use thumb to pull back skin
• Insert needle at 15 degree angle, bevel up
• Insert and fill vacutainer
• Remove needle
• Have Pt hold pressure for 3 minutes

Question 16

What is the anticoagulant used in purple tops?

Answer 16

• Ethylenediaminetetraacetic Acid (EDTA)

Question 17

When is EDTA typically used?

Answer 17

• CBC

- WBC Differential

Question 18

Overview of EDTA?

Answer 18

• Most commonly used anticoagulant
• Chelating agent that binds calcium so blood cannot clot
• Does not affect cellular morphology
• Specimens can be refrigerated for approx. 24 hours

Question 19

What is the powder anticoagulant used in light blue tops?

Answer 19

Sodium Citrate

Question 20

What is Sodium Citrate commonly used for?

Answer 20

• Prothrombin Time (PT)
• Partial Thromboplastin Time (PTT)
• Chelating agent that binds calcium

Question 21

What liquid or powder anticoagulant is used in green tops?

Answer 21

Heparin

Question 22

What is Heparin used for?

Answer 22

• Typically used for plasma studies and chemistry testing
• Ammonia
• Adrenocorticotropic hormone (ACTH)

Question 23

How does Heparin work?

Answer 23

• It inhibits the clotting enzyme, thrombin, by by creating an antithrombin
• Antithrombin prevents conversion of prothrombin into thrombin

Question 24

What is special about red tube tops and what are they used for?

Answer 24

• No anticoagulant or additives
• Commonly used for:
• Chemistry
• Serology
• Blood bank
• Other tests requiring serum

Question 25

What is a Serum Separator Tube (SST)/Gold/HIV Tube used for?

Answer 25

• No anticoagulant
• Contains serum separator gel
• Primarily used for chemistry testing

Question 26

What color top is Sodium Fluoride and what is it used for?

Answer 26

• Grey Tube
• Used for glucose studies
• ETOH analysis
• Inhibits Glycolysis

Question 27

What are some common procedural phlebotomy errors?

Answer 27

• Using IV sites
• Prolonged application of tourniquet
• Using wrong test tube
• Wrong draw order
• Short fill
• Not mixing the tube

Question 28

What is the proper draw order by tops?

Answer 28

• Blood culture tubes
• Blue tops
• Red tops
• SST
• Green top
• Lavender top
• Grey top

Question 29

What are some blood draw complications?

Answer 29

• Syncope
• Infection
• Continued bleeding

Question 30

What are issues with continued bleeding in blood draw complications?

Answer 30

• Anticoagulation medications
• Inadequate pressure
• Bending the elbow
• Collapsing the vein
• Failure to enter the vein
• Going through the vein
• Hematoma

Question 31

Proper procedure is hematoma occurs during blood draw?

Answer 31

• Integrity of vein is compromised (going through the vein)
• Stop procedure and apply pressure with clean gauze
• Elevate arm