1. Phlebotomy
Chapter 53

2. Learning Objectives
Define, spell, and pronounce the terms listed in the vocabulary.
List the equipment needed for venipuncture.
Explain the purpose of a tourniquet.
Explain how to apply a tourniquet and three consequences of improper application.
Explain why the stopper colors on evacuated tubes differ.
State the correct order in which various types of tubes should be collected.
Explain why a syringe is used for blood collection rather than an evacuated tube.

3. Learning Objectives
Detail patient preparation for venipuncture that displays sensitivity to patient rights and feelings.
Describe and name the veins that may be used for blood collection.
List, in order, the steps of a routine venipuncture.
Collect a venous blood sample using the evacuated tube method.
Explain the reasoning behind choosing a winged infusion set (butterfly) over an evacuated tube.

4. Learning Objectives
Summarize typical problems that may be associated with venipuncture.
Identify the major causes of hemolysis during a venous blood collection.
List situations in which capillary puncture would be preferred over venipuncture.
Discuss proper dermal puncture sites.
Describe containers that may be used to collect capillary blood.

5. Phlebotomy The practice of drawing blood. Phleb-vein
The most common method of obtaining blood is by venipuncture.
What are some reasons that a physician would perform blood work for a patient?

6. Vocabulary
Hemoconcentration-increase in the concentration of red blood cells in the circulating blood in proportion to the plasma.
Hemolysis- the destruction or dissolution of RBC’s with subsequent release of hemoglobin.
Plasma- the liquid portion of whole blood that contains active clotting agents.
Serum- the liquid portion of whole blood that remains after the blood has clotted.
Thixotropic gel- a material that appears to be a solid until subjected to a disturbance, such as a centrifugation, whereupon it becomes a liquid.
Centrifugation- This process is used to separate two immiscible (difficult to separate) liquids.

7. Basic Venipuncture Equipment
Venipuncture chair – adjustable locking armrest to protect fainting patient
Gloves:
Glove use during venipuncture is mandated by OSHA.
Caution with latex products
Tourniquet
Tied 3 to 4 inches above elbow immediately before venipuncture; a tourniquet on for longer than 1 minute may alter test results
When is it appropriate to ask a patient if he or she prefers to lie on a table to have blood drawn?
Why should you ask each patient if they have a latex allergy?
Explain the procedure for applying a tourniquet.

8. Venipuncture Equipment
Tourniquet
Prevents venous flow out of the site, causing veins to bulge.
Makes veins easier to locate and puncture.
From Flynn JC Jr: Procedures in phlebotomy, ed 3, Philadelphia, 2005, Saunders.
What types of tourniquets are available? How long can a tourniquet be left in place?
What happens if the tourniquet is left on the arm too long?

9. Venipuncture Equipment
Alcohol Pads-Antiseptics
70% isopropyl alcohol most commonly used
Alcohol does not sterilize skin; inhibits reproduction of bacteria that might contaminate the sample.
To be most effective alcohol should remain on skin 30 to 60 seconds.
Should not be used when drawing blood alcohol test. Sterile soap pads, benzalkonium chloride, or povidone-iodine (Betadine) can be used.
Give an example of when it would be best to use Betadine to cleanse a puncture site.
What is the procedure for cleansing a puncture site?

10. Equipment Used in Venipuncture
Double-pointed safety needles
Tourniquet
Pen
Evacuated stopper tubes
Alcohol swabs
Gauze
Needle holder
Bandages
Sharps container
Gloves
Syringes
Winged infusion sets (butterfly needles)

11. Venipuncture Equipment
Identify each of the items in this phlebotomy tray.
From Stepp CA, Woods MA: Laboratory procedures for medical office personnel, Philadelphia, 1998, Saunders.

12. Needles
The venipuncture needle has a shaft with one end cut at an angle (bevel).
The other end attaches to the syringe or to an adaptor (hub).
Gauge is designated by a numeric value.
The higher the number, the smaller the lumen.
Example: 18 gauge has a large lumen while a gauge has a small lumen.
Describe safety needle devices.
Explain the relationship between gauge numbers and lumen size.

13. Needle Safety Never recap a needle. Never recap a contaminated needle.
Dispose of used needles and needle holders promptly in appropriate sharps disposal containers.
Report all needle stick and other sharps-related injuries promptly to ensure that you receive appropriate follow-up care.
Use safety needles and shields.
Self-sheathing safety devices
How do these needle covers work?
Why is it important for employers to provide safety needle systems?
Modified from Garrels M, Oatis C: Laboratory testing for ambulatory settings, ed 2, St Louis, 2011, Saunders.

14. Syringes
Used when there is concern that the strong vacuum in a stoppered tube will collapse the vein.
The syringe needle fits on the end of the barrel and comes in different gauges.
It must be transferred immediately to another tube because the blood will clot in the syringe barrel.
When might a syringe be used to draw blood rather than a vacutainer?

15. BD Vacutainer Blood Transfer Device
Courtesy Becton, Dickinson & Company, Franklin Lakes, NJ.

16. Needle Holders Translucent cylinders.
Cylinders have a ring that indicates how far the tube can be pushed onto the needle without losing the vacuum.
Needles are not removed from the needle holder, and the safety feature must be activated before disposal.
Explain the purpose of needle holders.
What is done with them after the blood is drawn?

17. Vacutainer System and Holder (Evacuated tube)

18. Evacuated Collection Tube (Vacutainer)
Tubes of various sizes with color-coded tops indicating tube contents
Volumes range from 2 to 15 ml
Each test requires a specific amount of blood
For a test requiring 3 ml of serum 6 ml of blood must be collected
Match needle gauge to tube size; the larger the tube, the greater the vacuum and more likely blood will hemolyze if a high-gauge, small-lumen-sized needle is used.
Why is it important to use the appropriate size needle with a vacutainer?
How will you know how much blood is needed for each test ordered?
How much blood would you have to draw to get a 2-cc sample of plasma?

19. Order of Collection and Additives and Inversion Mixing (page 1135-1136)
The National Committee for Clinical Laboratory Standards developed a set of standards outlining the order of draw for a multi-tube draw.
1. Yellow topped tube-Used for blood cultures.
2. Red topped-contain no additives.
USES: chemistries, immunology, serology, blood bank (glass tube only)
For plastic tubes they must be inverted at least 5-6 times. If glass, no inversion is needed.
Explain the importance of following the proper order of collection.
What is meant by carryover?
What might happen if the appropriate order of collection is not followed?

20. Order of Collection and Additives
3. Light blue topped tubes-
ADDITIVE: Sodium Citrate USES: Coagulation tests ACTION: Forms calcium salts to remove coagulation and prevent clotting. REQUIREMENTS: FULL DRAW, invert 3-4 times
4. Green topped tubes.
ADDITIVE: Heparin USES: Chemistries ACTION: Anti-coagulant and gel seperates via centrifuge REQUIREMENTS: Invert 8-10 times.

21. Order of Collection and Additives
5. Lavender topped tubes.
Additive: EDTA
(ethylenediaminetetraacetic acid) Uses:Hematology, blood bank. Action:Forms calcium salts to remove coagulants and prevent clotting Requirements: Full draw. Invert 8-10 times
6. Red/gray marble topped tubes.
Additive: Serum seperator tube (SST gel) and clot activator.
Uses: chemistries, immunology and Serology Action: Gel seperates blood by centrifuge Requirements: Invert 5-6 times.

22. Order of Collection and Additives
7. Gray-topped tube. Additives: Sodium floride/potassium oxalate Uses: Glucose, alcohol and lactate levels Actions: Antiglycolytic preserves glucose for 5 days Requirements: Full draw . Invert 8-10 times.

23. Tube Additives Ethylenediaminetetraacetic acid (EDTA)
Lavender-topped tube
Prevents platelet clumping and preserves appearance of blood cells for microscopic examination
Clot activators promote clotting of blood
Silica particles
Thrombin quickly promotes clotting; used in tubes drawn for stat chemistry testing or for patients taking anticoagulants
Without a clot activator, blood will clot in 30 to 60 minutes, after which it must be centrifuged .
Discuss the different additives placed in tubes and their associate tube top colors.

24. Tube Additives Anticoagulants prevent blood from clotting
Whole blood sample – CBC and blood typing
Centrifuge sample to separate plasma from blood cells – plasma used for stat chemistry testing and coagulation studies
Thixotropic gel- a material that appears to be a solid until subjected to a disturbance such as a centrifugation where upon it becomes a liquid.
When are each of these vacutainer types appropriate?

25. Winged Infusion Sets (Butterfly Needles)
Designed for use on small veins such as those in the hand or in pediatric patients.
Needle size is 23 gauge.
Needle is ½ to ¾ inch long with a plastic, flexible butterfly-shaped grip attached to a short length of tubing.
When is it appropriate to use a winged infusion set?
What is the typical needle size?

26. Refer to the Steps to Performing a Venipuncture Handout
Routine Venipuncture
Refer to the Steps to Performing a Venipuncture Handout
What is an acceptable method for identifying the patient in the ambulatory care setting?
How do you establish informed consent for patients who are ordered venipunctures?
When is it acceptable to touch the venipuncture site with your finger?
Review Standard Precautions that should be used for each blood draw.

27. Choice of Veins Survey the arm thoroughly.
Veins bounce lightly when palpated.
The cephalic veins run lateral or to the outside of the antecubital area.
Median cubital (cephalic) vein is first choice of draw.
The basilic vein lies in the inside part of the antecubital area and is close to brachial artery and median nerves. Because it lies close to these areas, it is the last choice of draw.

28. Veins of the Forearm (page 1140)

29. Phlebotomy Requisitions
Must have the following information:
Patient name
Date of birth
Identification number
Name of physician making the request
Type of test requested
Test status (timed, fasting, stat, and so forth)
Summarize the information that must be included on a laboratory form for phlebotomy procedures.

30. Problems Associated with Venipuncture (page 1149)
Failure/unable to obtain blood
IV Therapy
Mastectomy
Burned area
Nausea
Convulsions
Petechiae
Scarred veins
Edema
Hematoma
Syncope
Review Table 53-4 and discuss.
How can a hematoma form?
What should you do if the patient has a history or vertigo or syncope during past venipunctures?

31. Specimen Recollection
Unlabeled or mislabeled specimen
Quantity not sufficient
Defective tube
Incorrect tube used for test ordered
Hemolysis
Clotted blood in an anticoagulated specimen
Improper handling
Discuss reasons that phlebotomy must be repeated.
How can these problems be averted?

32. Capillary Puncture
Capillaries are small blood vessels that connect arterioles to small venules.
A capillary (or dermal) puncture is an efficient means of collecting a blood specimen.
Only a small amount of blood is required.
Capp puncture is used when a patient’s condition makes venipuncture difficult.

33. Capillary Puncture Examples: Older patients
Pediatric patients (especially under the age of 2 years)
Patients who require frequent glucose monitoring
Patients with burns or scars in venipuncture sites
Obese patients
Patients receiving intravenous therapy
Patients who have had a mastectomy
Patients at risk for venous thrombosis
Patients who are severely dehydrated
Tests that require a small volume of blood
When venous blood and capillary blood are not identical
Why might you need to perform a capillary puncture on an elderly patient?
Where are pediatric capillary sticks performed?

34. Capillary Puncture Equipment
Collection containers
Skin puncture device
Lancet
Courtesy Becton, Dickinson & Company, Franklin Lakes, NJ.

35. Equipment
Manufacturers also provide various collection devices designed to obtain small quantities of blood for “point-of-care” testing for analytes such as glucose, hemoglobin A1c, and cholesterol
Paper cards (Guthrie Cards)-used to test neonates for metabolic disorders such as PKU (phenylketonuria).
Discuss the equipment needed to perform a capillary stick.

36. Capillary Puncture Site selection Usually ring finger
Middle finger preferred
Heel stick for infants under age of 1
Thumb is too callused
Index finger has extra nerve endings thus makes it too painful.
Pinky has too little tissue for a successful puncture.
Discuss Procedure 53-4.
What sites might be used?

37. Capillary Puncture
Preparation-follow all aseptic procedure and gather all equipment necessary.
Collecting Specimen
Puncture is made at the tip and slightly to the side of the finger.
Puncture a fleshy area closer to the center of the finger to prevent damage to underlying bone.
Avoid areas that are scarred, burned, infected, cyanotic, or edematous.

38. Capillary Puncture

39. Pediatric Phlebotomy
Performed only by personnel trained in the techniques for pediatric phlebotomy.
Tactfully determine if the parent is comfortable with assisting in restraining an uncooperative child.
Refer to Table 53-7 page 1156.
Collect blood by dermal puncture for those under 2 years of age; may use dorsal hand vein with 23-gauge winged infusion set.
Discuss Table How could you gain the cooperation of a child ordered to have a phlebotomy?
Refer to Table What is it important to limit the amount of blood drawn from pediatric patients?
What equipment is used to perform pediatric phlebotomy?

40. Handling Specimens Most samples are centrifuged
Should be refrigerated and tested within 72 hours
Blood may be drawn for drug and alcohol testing, DNA analysis, or parentage testing
Samples must be handled according to special procedures to prevent tampering, misidentification, or interference with the test results
Follow chain of custody procedures
Correctly handling and storing samples is crucial to laboratory results.
Describe guidelines for proper handling and storage.
Why are most blood samples centrifuged before transport to a referral lab?
Explain the meaning of chain of custody procedures.
What antiseptic should you use when doing phlebotomy for alcohol screening?

41. Patient Education
The medical assistant must maintain a professional attitude and still be sympathetic to the fears and apprehensions of the patient.
Use the patient’s suggestion in choosing the site for the removal of a blood specimen.