CHAPTER 17 PHLEBOTOMY. Elsevier items and derived items © 2008 by Saunders, an imprint of Elsevier Inc.2 PRETEST 1.An individual who collects blood specimens

CHAPTER 17 CHAPTER 17 PHLEBOTOMY

Elsevier items and derived items © 2008 by Saunders, an imprint of Elsevier Inc. 2

PRETESTPRETEST

1. An individual who collects blood specimens is known as a vampire.

2. The purpose of applying a tourniquet when performing venipuncture is to make the patient's veins stand out.

3. The tourniquet should be left on the patient's arm for at least 2 minutes before performing a venipuncture

4. Serum is obtained from whole blood that has been centrifuged.

5. A 25-gauge needle is recommended for performing venipuncture.

True or False


PRETEST, CONT. PRETEST, CONT.

6. The size of the evacuated tube used to obtain a venous blood specimen depends on the size of the patient's veins.

7. A correct order of draw for the vacuum-tube method of venipuncture is red, lavender, gray, and green.

8. Veins are most likely to collapse in patients with large veins and thick walls.

9. Hemolysis of a blood specimen results in inaccurate test results.

10. When obtaining a capillary specimen, the first drop of blood should be used for the test.

True or False


Content OutlineContent Outline

1. Purpose of phlebotomy: collect blood for laboratory analysis

a. Phlebotomy: Incision of a vein for the removal of blood

2. Phlebotomist: individual collecting the blood sample

Introduction to Phlebotomy


Introduction to Phlebotomy, cont.


1. Specimen may be:

a. Tested at office

b. Taken to an outside laboratory for testing

– Must be placed in a biohazard specimen bag




• Needs to be accompanied by a laboratory request

– Informs laboratory what tests to run

– MA completes laboratory request

1) On computer

2) Manually (by hand)




4. Types of blood collections:

a. Arterial puncture: performed in a hospital setting

b. Venipuncture

c. Skin puncture


Venipuncture (VP)Venipuncture (VP)

1. Venipuncture (VP): Puncturing of a vein for the removal of a venous blood sample

2. Performed when a large blood specimen is needed for testing


Venipuncture (VP), cont. Venipuncture (VP), cont.

3. Methods

a. Vacuum tube: use of evacuated tube (glass or plastic tube containing a vacuum)

• Fastest

• Most convenient

• Most often used


Venipuncture (VP), cont. Venipuncture (VP), cont.

b. Butterfly and syringe: for difficult draws

• Small veins

• Sclerosed (hardened veins)


General Guidelines for Venipuncture

General Guidelines for Venipuncture

1. Provide patient with advance preparation (if required)

a. Most tests require no preparation

Patient Preparation for Venipuncture


Patient Preparation for Venipuncture, cont.


b. Most common preparation

• Fasting: Abstaining from food or fluid (except water) for a specified amount of time

– Usually 12 to 14 hours

• Avoidance of medication




c. Patient preparation listed in reference sources

• Outside laboratory:

– Laboratory directory

– Tech support

• Physician’s Office Laboratory (POL)

– Instructions included with blood analyzers and testing kits




d. Ask patient if he has prepared properly before performing VP

• If patient has not prepared: do not collect specimen

– Unless directed by physician

– If VP is rescheduled: review preparation requirements with patient




2. Explain VP procedure in an unhurried and confident manner

a. Helps reduce patient fears

• Relaxes veins

– Makes procedure easier to perform

– Less pain for patient




3. Identification of the patient

a. Avoids collecting specimen on wrong patient

• Could lead to inaccurate diagnosis and wrong treatment

b. Ask patient to state full name and date of birth

• Compare with information in patient's chart




4. Instruct patient to remain still

5. Tell patient that a small amount of pain is associated with procedure

a. NEVER tell the patient the VP will not hurt




6. Just before inserting needle: Tell patient he will "feel a small stick"

a. Avoids startling patient: could cause patient to move

• Movement causes pain

• Could damage VP site


Patient Position of Venipuncture

Patient Position of Venipuncture

1. Important to a successful collection

2. Proper positioning:

a. Allows easy access to vein

b. More comfortable for patient

3. Position depends on vein being used


Patient Position of Venipuncture, cont. Patient Position of

Venipuncture, cont.

4. Most common VP site: antecubital space

a. Patient should be seated in chair

b. Arm extended in downward position

• To form straight line from shoulder to wrist

– With palm facing up

– Arm should not bend at elbow


Antecubital SpaceAntecubital Space



Venipuncture, cont.

c. Arm should be well supported on armrest:

• By rolled towel

• By patient placing fist of the other hand under elbow



Venipuncture, cont.

5. Never have patient on stool or standing

a. Fainting could occur: patient may be injured

6. If patient has fainted in the past from VP or is nervous:

a. Place in semireclining position on examining table



Venipuncture, cont.

7. Venous reflux: blood flows from evacuated tube back into patient's vein during procedure

a. Could cause patient to have adverse reaction to a tube additive• Particularly ethylenediaminetetraacetic acid

(EDTA)

b. To prevent: keep patient's arm in a downward position• Evacuated tube remains below the VP site

– Fills from the bottom up


Application of the TourniquetApplication of the Tourniquet

1. Purpose: makes patient's veins stand out so they are easier to palpate

2. Causes venous blood to slow down and pool in veins in front of tourniquet

a. Makes veins more prominent

• More visible

• Can be palpated


Application of the Tourniquet, cont.


3. When applying: important to obtain correct tension

a. Should slow venous flow without affecting arterial flow

b. Too tight: obstructs both arterial and venous flow

• May produce inaccurate test results




c. Too loose: veins will not stand out enough to be palpated

d. Correct tension:

• Should fit snugly

• Not pinch skin




4. Guidelines for Applying the Tourniquet

a. Do not apply over sores or burned skin

b. Place 3 to 4 inches above bend

in elbow

• Allows adequate room for:

– Cleansing site

– Performing VP




c. Apply tourniquet so that it is snug

• Should not pinch patient's skin

• Should not be painful to patient

d. Ask patient to clinch fist: pushes blood from lower arm into veins for easier palpation

• Ask patient to clench and unclench fist a few times

– Avoid vigorous pumping: could lead to hemoconcentration




e. Never leave on for more than 1 minute

• Uncomfortable for patient

• Causes venous blood to stagnate: venous stasis

– Plasma filters into tissues: causes hemoconcentration




• Hemoconcentration: An increase in the concentration of blood components

– Caused by a decrease in fluid content of the blood

– Can alter test results




f. Remove tourniquet when good blood flow is established

• When first learning venipuncture: best to remove tourniquet just before removing needle

– May move needle

1) No more blood flow

2) Must redraw




g. Always remove tourniquet before removing needle

• If needle removed first: blood forced out of puncture site causing a hematoma

– Hematoma: A swelling or mass of coagulated blood caused by a break in a blood vessel

h. Wipe tourniquet with a disinfectant (alcohol) if reusable

• Throw away if disposable


Remove Tourniquet Before Removing Needle

Remove Tourniquet Before Removing Needle




5. Types of Tourniquets

a. Rubber Tourniquet: flat, soft band of rubber

• 1 inch wide

• 15 to 18 inches long

• Advantage: easily removed with one hand




• Position:

– 3 to 4 inches above bend in elbow

– Should lie flat against' patient's skin

– Flaps must be directed upward so do not dangle in working area


Application of TourniquetApplication of Tourniquet




6. Velcro-Closure Tourniquet

a. Band of rubber or elastic with Velcro attached at ends

b. Advantage

• Easier to apply than rubber tourniquet

• More comfortable for patient




c. Disadvantage:

• More difficult to remove

• May not fit around arm of obese patients


Velcro-Closure TourniquetVelcro-Closure Tourniquet


Site Selection for Venipuncture

Site Selection for Venipuncture

1. Best site for most patients: veins in antecubital space

a. Easy to draw blood

• Patient with large visible veins

– Difficult to draw blood

1) Small veins

2) Veins that cannot be palpated


Site Selection for Venipuncture, cont.


1. Antecubital space: surface of arm in front of elbow




3. Antecubital veins:

a. Usually have wide lumen

b. Close to surface of skin

• Makes them easily accessible




c. Usually have thick walls:

• Less likely to collapse

d. Skin is less sensitive: less pain for patient

4. Do not use small spidery veins on surface of skin

a. Not suitable for VP

b. Antecubital veins lie beneath these veins




5. Veins to use in antecubital space:

a. Median cubital: best vein

• Large vein: does not roll

– Located in middle of antecubital space

• Cannot be used:

– When it lies deep in the tissues: cannot be palpated

– Is scarred from repeated VPs




b. Basilic and cephalic: located on opposite sides of antecubital space

• Use: when median cubital cannot be used

– Cephalic: located on thumb side of hand

– Basilic: located on little-finger side of hand

1) Disadvantage: may roll and escape puncture

2) To prevent: Apply firm pressure below vein to stabilize it


Antecubital VeinsAntecubital Veins




6. Brachial artery: also located in antecubital space (used to measure blood pressure)

a. Lies deeper in the tissues

b. Artery pulsates, is more elastic, and has a thicker wall than a vein

c. If punctured: patient feels more pain and blood is bright red and comes out pulsing

• If occurs:

– Remove tourniquet and then needle

– Apply pressure with gauze pad for 4 to 5 minutes


Guidelines for Site SelectionGuidelines for Site Selection

7. Guidelines for Site Selection: Facilitates selection of a good vein

a. Ensure adequate lighting

• Facilitates selection of vein


Guidelines for Site Selection, cont.


b. Ensure that veins "stand out" as much as possible

• Apply tourniquet

• Ask patient to clench fist




c. Examine antecubital veins of both arms

• Patient may have larger veins in one arm than in other

– Ask patient which vein was previously used for VP




d. Use inspection and particularly palpation to select vein

• Vein does not have to be seen in order to be a good selection

– Palpation alone can be used to locate a vein

– Vein feels like an elastic tube

1) Gives under the pressure of the fingertips




e. Palpate for median cubital vein first

• Advantages over other antecubital veins:

– Usually bigger

– Anchored better

– Bruises less

– Poses smallest risk of injuring underlying structures (nerves)




• If median cubital cannot be seen but can still be palpated:

– Use as a first choice

• If median cubital is good in both arms

– Select the one that is the fullest




• Cephalic: second choice

– Does not roll and bruise as easily as basilic

• Basilic: last choice

– May cause injury to underlying structures:

1) In some individuals: branches of median nerve lie close to basilic

2) Lie in close proximity to brachial artery




f. Thoroughly assess vein

• Place one or two fingertips over vein

– Index and middle finger

• Press lightly: then release pressure

• Do not use thumb to palpate (not as sensitive)

• Suitable vein: feels round, firm, elastic, and engorged

– When an engorged vein is depressed and released: Springs back in a rounded, filled state




g. Determine size, depth, and direction of vein

• Thoroughly palpate vein




• Trace the path of the vein

– By rolling index finger back and forth over vein

1) Inspect and palpate vein for problems(a) Small(b) Hard(c) Bumpy(d) Flat




h. Mentally "map" puncture site on patient's arm with skin marks

• Site may be near freckle, wrinkle, pigmented area

– Helpful in making stick when vein cannot be seen and can only be palpated

i. Do not leave tourniquet on for more than 1 minute

• Causes:

– Patient discomfort

– Hemoconcentration




j. Techniques to make veins more prominent:

• Remove tourniquet and have patient dangle arm over side of chair 1 to 2 minutes

• Tap vein site sharply with index finger and second finger

• Gently massage arm from wrist to elbow

• Apply warm, moist washcloth for 5 minutes


Alternative Venipuncture SitesAlternative Venipuncture Sites

1. Alternative sites

a. Inner forearm

b. Wrist area above thumb

c. Back of hand


Alternative Venipuncture SitesAlternative Venipuncture Sites


Alternative Venipuncture Sites, cont.


2. Alternative veins:

a. Smaller than antecubital veins

b. Have thinner walls

3. Use alternative veins when all possibilities at antecubital site have been considered

a. Example: May be able to use butterfly on a small antecubital vein




4. Use veins in hands as a last resort:

a. Have a tendency to roll because:

• Not supported by much tissue

• Close to the surface of the skin

– Makes them more difficult to stick




b. Abundant supply of nerves in hand

• Makes procedure uncomfortable for patient

c. Thin walls

• Make them susceptible to:

– Collapsing

– Bruising

– Phlebitis




5. In some patients: hand veins may be only accessible site

a. Examples:

• Obese patients

• Elderly patients


What Would You Do?What Would You Not Do?






Types of Blood SpecimensTypes of Blood Specimens

1. Type of blood specimen required: depends on type of test to be performed

a. Examples:

• Serum: required for most blood chemistry studies

• Whole blood: required for a complete blood count (CBC)


Types of Blood Specimens, cont.


2. Clotted blood: obtained from tube with no anticoagulant

a. Causes blood cells to clot

3. Serum: obtained from clotted blood

a. Allow specimen to stand and then centrifuge it

b. Because tube does not contain an anticoagulant, separates into:• Top layer: Serum

• Bottom layer: Clotted blood cells






4. Whole blood: Obtained from tube containing an anticoagulant to prevent clotting of blood cells

a. Tube must be gently rotated 8 to 10 times after collection

• To mix anticoagulant with blood




5. Plasma: obtained from whole blood that has been centrifuged

a. Because tube contains an anticoagulant, separates into:

• Top layer: plasma

• Middle layer: buffy coat (white blood cells and platelets)

• Bottom layer: red blood cells (RBCs)




OSHA Safety PrecautionsOSHA Safety Precautions

To avoid exposure to bloodborne pathogens during VP

1. Wear gloves.

2. Wear a face shield (or mask and eye protection):

a. Whenever splashes, spray, splatter, or droplets of blood may be generated.


OSHA Safety PrecautionsOSHA Safety Precautions

3. Perform all procedures involving blood in a manner to minimize splashing, spraying, splattering, and generating droplets of blood.

4. Bandage cuts before gloving.

5. Sanitize hands after removing gloves.

6. If hands or other skin surface comes in contact with blood:

a. Wash with soap and water immediately.


OSHA Safety Precautions, cont.


7. If mucous membranes come in contact with blood

a. Flush with water immediately

8. Do not break, bend, or shear contaminated venipuncture needles.

9. Do not recap contaminated venipuncture needle.




10.Locate the sharps container as close as possible to the area of use

a. Immediately after use: discard VP setup in biohazard sharps container




1. Place blood specimens in containers that prevent leakage during collection, handling, processing, storage, transport, and shipping.

2. If exposed to blood: report incident immediately to your physician-employer


Vacuum Tube Method of Venipuncture

Vacuum Tube Method of Venipuncture

1. Frequently used to collect venous blood specimens

2. Ideal for collecting blood from antecubital veins that are of adequate size

a. To withstand the pressure of the vacuum in the evacuated tube


Vacuum Tube Method of Venipuncture, cont.


3. Vacuum tube system:

a. Collection needle

b. Plastic needle holder

c. Evacuated tube




1. Commercially available system: Vacutainer


NeedleNeedle

1. Double-pointed needle with threaded hub

a. Screws into plastic holder

2. Packaged in sealed twist-apart container

a. Do not use if seal is broken

b. Printed on paper seal:

• Needle gauge

• Needle length


Needle, cont. Needle, cont.

3. Needle consists of:

a. Anterior needle: Is longer and has a beveled point

• Bevel: Facilitate entry into skin and vein



b. Posterior needle: pierces rubber stopper of evacuated tube

• Needle has a rubber sleeve: functions as a valve

– When needle pushed into rubber stopper: sleeve compresses

1) Exposes needle opening

2) Allows blood to enter tube


Needle, cont.Needle, cont.

– When tube removed: sleeve slides back over needle opening

1) Closes off opening

2) Stops flow of blood



4. Gauge sizes for VP: 20 to 22

a. 21 gauge: most commonly used

5. Length of needle: 1 inch and 1½ inches


Needle, cont.Needle, cont.

a. Length used: based on individual preference

• 1 inch:

– Less intimidating to patient

– Offers more control during stick

• 1½ inch:

– Allows more room for stabilizing vein


Gauge and Length of NeedleGauge and Length of Needle


Safety-Engineered Venipuncture Devices

Safety-Engineered Venipuncture Devices

1. OSHA stipulates requirements

a. To reduce needlestick and other sharps injuries among healthcare workers

2. Employers must evaluate and implement safer medical devices

a. Includes safety-engineered VP devices


Safety-Engineered Venipuncture Devices, cont.

Safety-Engineered Venipuncture Devices, cont.

b. Have a built-in safety features

• To reduce risk of needlestick injuries


Plastic HolderPlastic Holder

1. Consists of plastic cylinder with two openings

a. Small opening: used to secure needle

b. Large opening: holds evacuated tube


Plastic Holder, cont. Plastic Holder, cont.

2. Flange: extension on large openinga. Assists in

insertion and removal of tubes

b. Prevents holder from rolling when placed on a flat surface


Plastic Holder, cont. Plastic Holder, cont.

3. Indention on holder

a. Marks point at which posterior needle starts to enter rubber stopper of tube

• Do not insert tube stopper past this point before entering vein

– Causes tube to fill with air

– Blood is not able to enter the tube


Evacuated TubesEvacuated Tubes

1. Glass tube with rubber stopper

2. Contains vacuum that creates suction

a. Pulls blood specimen into tube

3. Tube additive must not:

a. Alter blood components

b. Affect laboratory test


Evacuated Tubes, cont. Evacuated Tubes, cont.

4. Color-coded for easy identification of additive

a. Red: does not contain an anticoagulant

• Used to obtain clotted blood or serum

– Serum required for:

1) Serologic tests

2) Most blood chemistries



b. Lavender: EDTA (anticoagulant)

• Used to obtain whole blood or plasma

– Most common use: collect a blood specimen for a CBC



c. Light blue: sodium citrate (anticoagulant)


– Most common use: coagulation tests (e.g., prothrombin time)



d. Green: heparin (anticoagulant)

• Used for blood gas determinations and pH assays

e. Gray: sodium fluoride/potassium oxalate (anticoagulant)


– Most common use: glucose tolerance test



f. Dark blue: heparin or no additive

• Made of refined glass and special stopper

• Used to detect trace elements (e.g., lead, arsenic)


Evacuated TubesEvacuated Tubes



5. Additive tube used depends on type of test performed

a. MA must determine correct stopper color

b. Example: CBC requires lavender stoppered tube

c. Do not substitute one additive tube for another

• Leads to inaccurate results


6. Tubes available in different sizes: 2, 3, 5, 7, 10, and 15 ml a. Size selected: depends on the amount of

specimen required for the test

7. Information on amount of specimen and stopper color required

• Outside laboratory: indicated in laboratory directory

• POL: indicated in instructions accompanying blood analyzer or testing kit



8. Label of tube and vacuum tube box indicates:

a. Additive content

b. Expiration date

c. Tube capacity

d. Fill indicator

-To indicate when vacuum has been exhausted: tube is full


Hemogard Closure Tubes Hemogard Closure Tubes

9. Hemogard closure tubes

a. Newer type of evacuated tube

b. Consists of:

• Plastic closure that fits over a rubber stopper and overhangs outside of tube

c. When top removed:

• Reduces likelihood of contacting contents of tube

– Reduces splattering of blood


Hemogard Closure Tubes, cont.

Hemogard Closure Tubes, cont.

d. Regular evacuated tube: pops as top is removed

• May result in splattering of blood

e. Tube made of plastic: reduces possibility of tube breakage

f. Color coding is similar to rubber-stoppered tubes


Hemogard Closure TubesHemogard Closure Tubes


Order of Draw for Multiple Tubes

Order of Draw for Multiple Tubes

1. Blood culture tube

a. Drawn first to prevent contamination by other tubes


Order of Draw for Multiple Tubes, cont.


2. Coagulation tubes (light blue)

a. Prevents additives from other tubes from getting into tube

b. If butterfly used to collect specimen: modification in technique required

• Butterfly tubing: contains air

• If blue tube is first or only tube drawn

– Must draw 5-ml red tube first and discard




• Some of tube's vacuum: exhausted by air in tubing

– Results in underfilling tube

– Underfilled tube: results in incorrect anticoagulant to blood ratio

1) When performing coagulation test

2) Causes inaccurate result

a) To prevent: draw a red tube first and discard




3. Serum tubes

a. Includes:

• Tubes with or without a clot activator (red-stoppered)

• Serum separator tubes (SST) (red/slate gray stoppered)

b. Prevents contamination of nonadditive tubes by tubes with an anticoagulant




4. Anticoagulant tubes in this order:

a. Green

b. Lavender

c. Gray

• Prevents cross-contamination between different types of anticoagulants

– Cross-contamination: may lead to inaccurate test results








Evacuated Tube GuidelinesEvacuated Tube Guidelines

1. Select proper tubes

a. According to tests being performed

b. Amount of specimen required


Evacuated Tube Guidelines, cont.


1. Check tubes for cracks: will no longer have a vacuum

2. Check expiration date: outdated tube may not have a vacuum




4. Label tube with: Patient's name, date, MA's initials

a. Avoids mixing up specimens

b. Office may use bar codes to identify specimens




5. Powdered additive tubes (gray-stoppered tube)

a. Gently tap tube just below stopper

• Dislodges additive from stopper

• If additive is trapped in stopper

- Could cause erroneous test results




6. Take precautions to avoid premature loss of vacuum

a. Can be caused by:

• Dropping tube

• Pushing posterior needle through stopper before puncturing vein

• Partially pulling needle out of patient's arm during VP




7. To make puncture:

a. Use a continuous steady motion

• At a 15-degree angle to patient's skin




b. Do not use:

• Slow timid motion

– Painful to patient

• Rapid, jabbing motion

– Painful to patient

– Could cause needle to go through vein resulting in:

1) Failure to obtain blood

2) Hematoma




8. Follow proper order of draw to prevent:

a. Contamination of nonadditive tubes with additive tubes

b. Cross-contamination between different types of additive tubes

• Leads to inaccurate test results




9. Fill tubes until vacuum is exhausted

a. Blood ceases to flow into tube

b. Tube will be almost, but not quite full

c. If tube removed before vacuum exhausted

• Rush of air enters tube

– Damages RBCs

d. Tube with anticoagulant: ensures proper ratio of additive to blood




10.Remove last tube from plastic holder before removing needle from vein

a. Prevents blood from dripping out of needle after withdrawing it




11.Mix tubes containing anticoagulant immediately after drawing

a. Rotate tube gently 8 to 10 times

• Provides adequate mixing without causing hemolysis

• Hemolysis: the breakdown of blood cells

– Shaking tube: can result in hemolysis


Rotate Tube with Anticoagulant

Rotate Tube with Anticoagulant




b. Clotting of blood can be caused by:

• Not mixing tubes immediately

• Inadequate mixing

– May cause inaccurate test results




12.After VP: top of stopper may contain residual blood

a. Follow OSHA standard when handling tubes


Butterfly Method of Venipuncture


1. Also called winged infusion method

a. Winged infusion set: used to perform the procedure

2. Term 'butterfly': derived from plastic wings located between needle and tubing




3. Advantages:a. Provides better control when making

puncture

b. Less pressure exerted on vein from evacuated tube– Pressure must travel through a length of

tubing– Minimizes pressure on vein


Butterfly Method of Venipuncture, cont. Butterfly Method of Venipuncture, cont.

4. Recommended for:

a. Adult patients with small antecubital veins

b. Children: typically have small antecubital veins

c. When antecubital veins not available

• Alternative site is used (e.g., hand)

– May occur with elderly or obese patients


Butterfly Method of Venipuncture, contButterfly Method of Venipuncture, cont

5. Alternative sites

a. Veins are smaller

b. Have a thin wall

c. More likely to collapse



6. Gauge of needle: 21 to 23

7. Length of needle: ½ to ¾ inch

a. Needle: short and sharp

• Makes it easier to stick difficult veins



8. For an extremely small vein:

a. Use a 23-gauge needle

• To prevent rupture of vein

b. Use smaller volume tube (2 ml)

• Large tube: too much vacuum pressure on vein

– Vein may collapse



9. Needle attached to tubing

a. Tubing lengths:

• 6 inch

• 12 inch



10. Adapters for winged infusion sets:

a. Luer adapter: attached to posterior needle

• Plastic holder screwed onto Luer adapter

b. Hub adapter: used to attach a syringe


Adapters for Winged Infusion Set

Adapters for Winged Infusion Set



11. Safety needles available

a. Shield that covers contaminated needle


Guidelines for the Butterfly Method

Guidelines for the Butterfly Method

1. Patient position

a. Antecubital, wrist, and forearm veins

• Arm in straight line from shoulder to wrist


Guidelines for the Butterfly Method, cont.


b. Hand veins

• Hand on armrest

– Have patient make a loose fist or grasp a rolled towel

– Causes hand veins to stand out

• Locate vein between knuckles and wrist bones




2. Position of tourniquet

a. Forearm or wrist: 3 inches above site

b. Hand: just above wrist bone




3. Compress plastic wings together

a. Insert with bevel up

• At 15-degree angle to skin

b. After entering vein: decrease angle to 5 degrees


Insertion of NeedleInsertion of Needle




4. Slowly thread needle inside vein an additional ¼ inch

a. Anchors (seats) needle in center of vein

• Can use both hands to change tubes

5. To prevent venous reflux:

a. Keep tube and holder in a downward position

• Ensures that tube fills from bottom up




1. Follow proper order of draw (same as for vacuum tube method)


Syringe Method of Venipuncture

Syringe Method of Venipuncture

1. Least used method

a. Amount of blood collected limited by size of

syringe

b. Blood specimen must be transferred from syringe to evacuated tube

• Requires an additional step

2. Used to obtain blood from small veins

a. May collapse if vacuum tube method used


Syringe Method of Venipuncture, cont.Syringe Method of

Venipuncture, cont.

3. Offers more control than other methods

a. Rate of blood flow not dictated by tube vacuum



Venipuncture, cont.

4. Once vein is entered: specimen obtained by pulling back on plunger of syringe

a. Pull plunger slowly: minimizes pressure against vein

• Vein is less likely to collapse



Venipuncture, cont.

5. Set Up: Disposable needle and syringe

a. Needle gauge: 21 to 23

b. Needle length: 1 to 1½ inches



Venipuncture, cont.

c. Capacity of syringe depends on amount of specimen required

• Ranges from 5 ml to 20 ml (cc)

• If more than 20 ml needed: must perform a second VP



Venipuncture, cont.

6. After collection: transfer specimen to evacuated tube

a. OSHA requires a needleless device for the transfer

b. Order of fill: Same as order of draw for vacuum tube method

c. Tubes with additives: gently rotate 8 to 10 times immediately after filling


Problems Encountered with Venipuncture

Problems Encountered with Venipuncture

1. May occur with:

a. Obese patients:

• May have small superficial veins

• Suitable vein: buried deep in adipose tissue

Failure to Obtain Blood


Failure To Obtain Blood, cont. Failure To Obtain Blood, cont.

b. Elderly patients with arteriosclerosis:

• May have thick and hard veins

– Difficult to puncture

c. Small or thin-walled veins:

• May collapse



2. After two unsuccessful attempts:

a. Ask for assistance in obtaining blood specimen



3. Failure to obtain blood once needle has been inserted:

a. Not inserting needle far enough

• Prevents needle from entering the vein



b. Inserting needle too far: causes needle to go through vein

c. Bevel opening becoming lodged against wall of vein



4. Remove needle if blood not obtained

a. Do not probe vein

• Uncomfortable for patient

• May affect integrity of blood specimen

- Leads to inaccurate test results



5. Occasionally: evacuated tube may lose its vacuum

a. Cause:

• Manufacturing defect

• Improper handling of tube

b. Action: Remove tube and insert another one


Inappropriate Puncture SitesInappropriate Puncture Sites

1. Patient complains of pain or soreness at a potential site

a. Avoid site

2. Do not use areas that are:

a. Scarred

b. Bruised

c. Burned

d. Adjacent to areas of infection


Inappropriate Puncture Sites, cont.

Inappropriate Puncture Sites, cont.

3. Avoid an arm with edema

a. Makes it difficult to locate a vein

b. Takes longer for puncture to heal

4. Avoid arm to which a cast is applied

5. Avoid arm on the same side of a radical mastectomy


Scarred and Sclerosed VeinsScarred and Sclerosed Veins

1. Caused by:

a. Many venipunctures over period of years

• Scar tissue: develops in wall of vein

b. Elderly patients with arteriosclerosis

• Veins become thickened


Scarred and Sclerosed Veins, cont.


2. Veins feel stiff and hard

3. Difficult to stick

4. Blood return may be poor

a. Caused by narrowed lumen




5. Recommended: use another vein

a. If not possible:

• Insert needle with careful pressure

– To avoid going through vein


Rolling VeinsRolling Veins

1. Side veins have a tendency to roll

a. Cephalic

b. Basilic

2. To prevent rolling:

a. Apply firm pressure with thumb:

• Apply the pressure to the side of the vein and below vein

– Stabilizes the vein

– Keeps thumb out of the way when making puncture


Apply firm pressure below vein:

Apply firm pressure below vein:


Collapsing VeinsCollapsing Veins

1. Most likely to collapse:

a. Small veins

b. Veins with thin walls


Collapsing Veins, cont. Collapsing Veins, cont.

2. Most likely to occur with vacuum tube method

a. Sucking action of vacuum: causes vein to collapse

• Blocks flow of blood into tube

• Result: Small amount of blood enters tube and then stops


Collapsing Veins, cont.Collapsing Veins, cont.

3. Use butterfly or syringe method on patients with small veins

a. Better control

b. Less pressure on vein


Collapsed VeinCollapsed Vein


Premature Needle WithdrawalPremature Needle Withdrawal

1. Needle comes out of vein prematurely

2. Caused by

a. Patient movement

b. Improper VP technique


Premature Needle Withdrawal, cont.

Premature Needle Withdrawal, cont.

3. Blood is forced out of puncture site from pressure of tourniquet

4. Immediate action is required to prevent a hematoma

a. Remove tourniquet immediately

b. Place a gauze pad on site

c. Apply pressure with gauze until bleeding stops


HematomaHematoma

1. Blood leaks from puncture site of the vein into surrounding tissue

a. Results in a bruise


Hematoma, cont. Hematoma, cont.

2. Cause:

a. Needle inserted too far and goes through vein

b. Bevel opening is partially in vein and partially out of vein

c. Applying insufficient pressure after needle removal


Cause of a HematomaCause of a Hematoma


Hematoma, cont. Hematoma, cont.

3. First sign of hematoma: sudden swelling in area around puncture site

a. Remove tourniquet and needle immediately (if needle still in vein)

b. Apply pressure until bleeding stops


HemolysisHemolysis

1. Hemolysis: breakdown of blood cells

2. Blood cells are fragile

a. Rough handling may cause hemolysis

b. Produces inaccurate test results


Hemolysis, cont. Hemolysis, cont.

3. To prevent hemolysis:

a. Store tubes at room temperature

• Chilled tubes: can result in hemolysis

b. Allow alcohol to air dry completely

• Alcohol entering specimen: can cause hemolysis


Hemolysis, cont. Hemolysis, cont.

c. Do not use a small-gauge needle to collect specimen

• Causes RBCs to rupture as they pass through needle lumen

d. Practice good technique in collecting specimen

e. Always handle blood specimen tube carefully

• Do not shake or handle roughly


FaintingFainting

1. VP may cause dizziness or fainting

a. May occur during or after VP


Fainting, cont. Fainting, cont.

2. What to do

a. Protect patient from injury

• Example: prevent patient from falling

b. Place patient in position that promotes blood flow to brain

c. Notify physician for further treatment


Treatment for FaintingTreatment for Fainting


Obtaining a Serum SpecimenObtaining a Serum Specimen

1. Serum: plasma from which the clotting factor fibrinogen has been removed

2. Serum contains dissolved substances:

a. Glucose

b. Cholesterol

c. Lipids

d. Sodium

Serum


Serum, cont. Serum, cont.

e. Potassium

f. Chloride

g. Antibodies

h. Hormones

i. Enzymes


Serum, cont .Serum, cont .

3. Many laboratory tests require a serum specimen

a. To determine if substances are within normal range

b. To detect any substances that are not normally present


Tube SelectionTube Selection

1. To collect serum

a. Tube with no anticoagulants (red-stoppered)


Tube Selection, cont. Tube Selection, cont.

2. Serum recovered: only part of total blood specimen

a. Must use a tube that is 2½ times amount required for test

• Example: To obtain 2 ml of serum, must use a 5-ml tube

– Must use a 5-ml red-stoppered tube (2 x 2½)


Serum in Red TubeSerum in Red Tube


Preparation of the SpecimenPreparation of the Specimen

1. Allow tube to stand upright at room temperature for 30 to 45 minutes

a. Allows clot formation: yields more serum


Preparation of the Specimen, cont.


2. If centrifuged immediately:

a. Clotting factors do not have time to settle into cell layer

b. Result: formation of a fibrin clot in serum layer

• Spongy substance that occupies space

– Interferes with adequate serum collection




3. Do not let blood stand for more than 1 hour

a. Leaching of substances from cell layer into serum

• Leads to inaccurate test results


Removal of SerumRemoval of Serum

1. After allowing specimen to stand: centrifuge specimen


Removal of Serum, cont. Removal of Serum, cont.

2. Remove serum with a pipette and place in transfer tube

a. Do not disturb cell layer of the clot

• Draws RBCs into serum layer

b. If cells enter serum: recentrifuge specimen


Removing SerumRemoving Serum



3. Hold serum up to light to:

a. Inspect for presence of:

• Intact RBCs

• Hemolyzed blood


Inspect SerumInspect Serum



b. If present: specimen has a reddish appearance

• Must recentrifuge

4. After centrifuging intact RBCs:

a. Cells settle to bottom of tube

b. Serum can be removed



5. After centrifuging hemolyzed blood:

a. Serum will still have a reddish appearance

• RBCs have ruptured

• Releases hemoglobin into serum

b. Not suitable for laboratory tests: inaccurate test results

c. Must collect another specimen


Serum Separator Evacuated Tubes (SST)


1. Facilitates collection of serum specimen

2. Identified by red and slate-gray stopper




1. Used for collection and separation of blood

2. Thixotropic gel in bottom of tube


Serum Separator Evacuated Tubes (SST), cont.


5. Blood collected and placed upright for 30 to 45 minutes: allow for clot formation

6. During centrifugation:

a. Gel temporarily becomes fluid

b. Moves to dividing point between serum and clotted cells

c. Re-forms into a solid gel

7. Serves as a barrier between serum and clot


Gel Forms a BarrierGel Forms a Barrier




8. Serum can be transported in SST

a. Inspect tube carefully

9. To make sure gel barrier firmly attached to glass wall

a. If a complete barrier has not formed:

• Remove serum: place in transfer tube

– Prevents leaching of substances from cell layer into serum (leads to inaccurate test results)


Obtaining a Plasma SpecimenObtaining a Plasma Specimen

1. Plasma: The liquid portion of blood

a. Consists of a straw colored fluid

b. Makes up 55% of the blood volume

Plasma


Obtaining a Plasma Specimen, cont.

Obtaining a Plasma Specimen, cont.

2. Transports substances through body

3. Blood cells are suspended in plasma

a. Are circulated through the body


Plasma, cont.Plasma, cont.

4. Composition of plasma:

a. Water: 92%

b. Dissolved solid substances: 8%

5. Carried to and from tissues



6. Solutes present in plasma

a. Plasma proteins: serum albumin, globulins fibrinogen, prothrombin

• Serum albumin: regulates volume of plasma in the blood vessels

• Globulins: play role in immunity mechanism of body

• Fibrinogen and prothrombin: needed for proper blood clotting



b. Electrolytes: sodium, chloride, potassium, calcium, phosphate, bicarbonate, magnesium

• For normal cell functioning

• Maintenance of normal fluid and acid-base balance



c. Nutrients from breakdown of food substances: glucose, amino acids, lipids

• Nourish body tissues

d. Waste products: urea, uric acid, lactic acid, and creatinine

• Are excreted from body



e. Respiratory gases: carbon dioxide and small amount of oxygen

f. Substances that regulate and control body functions

• Hormones

• Antibodies

• Enzymes

• Vitamins


Tube SelectionTube Selection

1. To obtain a plasma specimen

a. Must use a tube with an anticoagulant

• Check laboratory directory: to determine color of stopper

2. Separating plasma from whole blood

a. Use same procedure as for separating serum from whole blood

3. Label transfer tube: plasma


Preparation and Removal of the Specimen

Preparation and Removal of the Specimen

1. Collect 2½ times amount required for test

2. Tap tube with powdered anticoagulant just below stopper:a. Releases anticoagulant from stopper

3. Allow specimen to fill to exhaustion of vacuuma. Ensures proper ratio of anticoagulant to

blood

b. Ensures accurate test results


Preparation and Removal of the Specimen, cont.


4. Gently rotate tube 8 to 10 times immediately after drawing

a. To mix anticoagulant with blood

5. Centrifuge 10 to 15 minutes (does not need to stand)

a. Packs cells and causes separation of blood into:

• Plasma

• Buffy coat

• RBCs




6. Separating plasma from blood

a. Use same procedure as for serum


Skin PunctureSkin Puncture

1. Used to obtain capillary blood specimen

2. Also called capillary puncture


Skin Puncture, cont. Skin Puncture, cont.

3. Testing done at medical office

4. Examples of tests

a. Hemoglobin

b. Hematocrit

c. Blood glucose

d. Mononucleosis

e. Prothrombin time



5. Skin puncture performed when:

a. Test requires small amount of blood

b. Preferred for infants and young children

• Venipuncture is difficult to perform on these age groups

c. Adult has no acceptable veins (as a last resort)



6. Before collecting specimen:

a. Select puncture site

b. Select skin puncture device

c. Obtain proper microcollection device


Puncture SitePuncture Site

1. Fingertip: preferred for adult

a. Third or fourth finger

b. Earlobe is no longer recommended

• Blood in earlobe contains a higher concentration of hemoglobin than fingertip

• Slower flow of blood: makes it harder to collect specimen


Puncture Site, cont. Puncture Site, cont.

2. Plantar surface of heel: infant (birth to 1 year)

a. Never perform finger puncture on an infant

• Amount of tissue between skin and bone is small

– Injury to bone is likely

• After child is walking

– Can perform on fingertip


Skin Puncture DevicesSkin Puncture Devices

1. Types

a. Disposable semiautomatic retractable lancet device

b. Reusable semiautomatic retractable lancet device

2. Depth of puncture

a. Adults: must not be deeper than 3.1 mm

b. Infants and children: must not be deeper than 2.4 mm


Skin Puncture Devices, cont. Skin Puncture Devices, cont.

3. If puncture is too deep: may penetrate bone

a. Could result in:

• Osteochondritis: inflammation of bone and cartilage

• Osteomyelitis: inflammation of bone due to bacterial infection

b. To prevent:• Use spring-loaded blade available in different lengths

– To control the depth of the puncture


Skin Puncture Devices, cont. Skin Puncture Devices, cont.

4. Blade length selected

a. Based on:

• Size of patient’s fingers

• Amount of blood specimen required


Skin Puncture Devices, cont.Skin Puncture Devices, cont.

a. Shorter blade

• Adults with thin fingers

• Children

• When only a drop of blood required

b. Longer blade

• To obtain enough blood to fill a microcollection device


Skin Puncture Devices, cont.Skin Puncture Devices, cont.

5. OSHA recommends: retractable lancets

a. To reduce sharps injuries


Disposable Semiautomatic Lancet

Disposable Semiautomatic Lancet

1. Spring-loaded plastic holder

a. Metal blade is inside holder


Disposable Semiautomatic Lancet, cont.


2. Different length blades available:

a. To control depth of the puncture

3. Plastic holder conceals blade:

a. Protects MA from accidental needlestick

b. Patient cannot see blade during puncture

• Results in less apprehension




4. To perform puncture:

a. Lancet device placed on patient's skin

b. Device is activated

c. Blade is forced into skin by spring

d. Blade retracts into the holder

e. Lancet device is discarded into biohazard sharps container


Disposable LancetDisposable Lancet


Reusable Semiautomatic Lancet

Reusable Semiautomatic Lancet

1. Wide variety available

a. Not all appropriate for use in medical office

2. Safest type: the part that may become contaminated is retractable and disposed of easily

a. Reduces risk of sharps injuries


Reusable Semiautomatic Lancet, cont.


3. Glucolet II: plastic, spring-loaded holder and a lancet/endcap

a. Plastic holder is reusable

b. Lancet is disposable




4. To perform puncture:

a. Lancet/endcap placed on skin

b. Release button depressed

c. Blade is forced into skin by spring

d. Blade retracts into the endcap

e. Lancet/endcap removed: discarded into biohazard sharps container


Reusable Lancet DeviceReusable Lancet Device


Microcollection DevicesMicrocollection Devices

1. Specimen may be placed directly onto a reagent strip

a. Example: blood glucose monitors

2. May be collected with microcollection device

a. Device used depends on laboratory equipment being used

• Examples:

– Capillary tubes

– Microcollection tubes


Capillary TubesCapillary Tubes

1. Consists of disposable glass or plastic tube

2. Depending on size: can hold 5 to 75 microliters of blood

3. Used for hematocrit determination


Microcollection TubesMicrocollection Tubes

1. Small plastic tube with removable blood collector tip

a. Tip designed to collect capillary blood from skin puncture

b. After collecting specimen:

• Collector tip removed, discarded and replaced by plastic plug


Microcollection Tubes, cont. Microcollection Tubes, cont.

c. Available with or without additives

d. Plugs color-coded to correspond with evacuated tube VP system


Guidelines for Performing a Finger Puncture


1. If laboratory test requires advance preparation:

a. Verify that patient prepared properly

2. Patient should be seated comfortably in a chair

a. Arm firmly supported

b. Palm facing up


Guidelines for Performing a Finger Puncture, cont.


3. Instruct patient to remain still

a. Just before making puncture:

• Tell patient a small stick will be felt

– Avoids startling patient: may cause patient to move




4. Use lateral part of tip of third or fourth finger of nondominant hand

a. Capillary bed is large

b. Skin is easy to penetrate

c. Puncture site should be free of:

• Lesions

• Scars

• Bruises

• Edema




d. Do not use index finger

• Skin is more callused: harder to penetrate

• Patient uses index finger more: will notice pain longer

e. Do not use little finger

• Amount of tissue between skin surface and bone is small

-Could result in injury to bone




5. Site may be warmed: increases blood flow

a. Gently massage finger from base to tip

b. Place hand in warm water




6. Cleanse site with antiseptic wipe and allow it to dry thoroughly

a. If alcohol is not dry:

• Round drop of blood does not form on the finger

– Blood leaches out on patient's skin: difficult to collect

• Alcohol can enter blood specimen

– Leads to inaccurate test results

1) Patient experiences a stinging sensation during puncture




7. Firmly grasp finger in front of most distal knuckle joint

a. Apply enough pressure to cause fingertip to become hard and red

• Ensures adequate penetration and depth of puncture

8. Select the site

a. Make puncture in fleshy portion of fingertip

• Slightly to the side of center




b. Do not puncture side or very tip of finger

• To prevent injury to the bone

c. Position blade perpendicular to lines of fingerprint (not parallel)

• Facilitates formation of well-formed drop of blood that is easy to collect

– If not perpendicular

1) Blood flow follows lines of fingerprint: runs down finger

a) Difficult to collect


Fingertip Puncture SitesFingertip Puncture Sites




9. Perform the puncture

a. Firmly press lancet device against puncture site

b. Activate spring-loaded device

c. If not enough pressure applied

• Puncture not deep enough

- Poor blood flow results

– May need to puncture patient again




d. With a good puncture: blood flows freely

e. Deep puncture hurts no more than superficial one




10.Wipe away first drop of blood with gauze pad

a. Diluted with alcohol and tissue fluid

• Not a suitable specimen: could cause inaccurate test results




11.Allow large drop to form by applying gentle pressure near puncture

a. Can massage the tissue surrounding the puncture site to promote blood flow

b. Do not squeeze excessively: causes dilution of specimen with tissue fluid

• May lead to inaccurate test results

c. Collect specimen

• Using appropriate microcollection device




12.Check site to make sure bleeding has stopped

a. Apply adhesive bandage if needed


POSTTESTPOSTTEST

True or False1. Venous reflux can be prevented by filling the

evacuated tube to the exhaustion of the vacuum.

2. If the tourniquet is applied too tightly, inaccurate test results may occur.

3. The median cubital vein is the best vein to use for venipuncture.

4. Upon standing, a blood specimen to which an anticoagulant has been added separates into plasma, buffy coat, and blood cells.

5. Whole blood is obtained by using a tube containing an anticoagulant.


POSTTEST, CONT.POSTTEST, CONT.

True or False6. An evacuated glass tube with a lavender stopper

contains EDTA.

7. A red stoppered tube is used to collect a blood specimen for most blood chemistries.

8. Not filling a tube to the exhaustion of the vacuum can result in hemolysis of the blood specimen.

9. If the needle is removed from the arm before removing the tourniquet, the evacuated tube will not fill completely.

10. If a fibrin clot forms in the serum layer of a blood specimen, it will lead to inaccurate test results.

Documents

CHAPTER 17 PHLEBOTOMY. Elsevier items and derived items © 2008 by Saunders, an imprint of Elsevier Inc.2 PRETEST 1.An individual who collects blood specimens