CHAPTER 17

Phlebotomy

Introduction to Phlebotomy

• Purpose of phlebotomy: collect blood for laboratory analysis

• Phlebotomy: incision of a vein for the removal of blood

• Phlebotomist: individual who collects the blood sample

Introduction to Phlebotomy

• Types of blood collections– Arterial puncture– Venipuncture– Skin puncture

• Venipuncture is the puncturing of a vein for the removal of a venous blood sample and is performed when a large blood specimen is needed for testing

Introduction to Phlebotomy

• Methods of Venipuncture– Vacuum tube – uses an evacuated tube and is the

fastest, most convenient, and most often used method

– Butterfly and syringe – used for difficult draws such as small or sclerosed veins

General Guidelines for Venipuncture

• Patient preparation– Fasting– Avoidance of medications– Special preparation required by outside

laboratories

Collection and Handling Requirements

• Collection Supplies• Type of specimen required• Amount of specimen required• Techniques for collecting specimen• Proper handling and storage of specimen

Assembling Equipment and Supplies

• Appropriate blood tubes– Ensure tubes are not broken, cracked or expired

• Label each blood tube– Unique patient identifiers, such as name and

date of birth– Date and time of collection as well as collector’s

initials• Laboratory requisition

Supplies and Equipment

• Venipuncture needle– Double pointed needle with threaded hub that

attaches to vacutainer– Has a bevel that facilitates easier insertion into the

skin and vein– Gauge sizes are 20 to 22 with 21 G being the most

common size used– Length is 1 to 1 ½ inches

Supplies and Equipment, cont.

• Vacutainer/Plastic Holder– Used to secure the needle and hold the evacuated

tubes• Evacuated tubes– Glass or plastic tubes with rubber stopper on one

end– Tubes have a vacuum that assists in drawing the

blood into the tube– Evacuated tubes have different colored stoppers

which indicate the type of additive in the tube

Supplies and Equipment, cont.

• Tourniquet– Makes patient veins stand out; they are easier to

see and palpate– Different types of tourniquets• Velcro closure• Rubber

– Latex and non-latex

Reassuring the Patient

• Explain the procedure• Instruct the patient to remain still• Tell patient there will be a small amount of

pain associated with the procedure• Make sure patient is ready for procedure; tell

them they will “feel a small stick”

Venipuncture – Vacuum Tube Method

• Review requirements and tubes from order• Sanitize your hands• Greet and identify patient; discuss previous

draw experiences• Assemble equipment– Tubes, vacutainer, needle, tourniquet, gloves,

alcohol pads, gauze, cotton, co-ban– Check for expirations on all equipment

Venipuncture – Vacuum Tube Method, cont.

• Prepare equipment• Place tube loosely in vacutainer • Apply tourniquet to assess veins• Take tourniquet off, clean area with alcohol• Put tourniquet back on, position arm• Anchor vein using thumb and first finger of

non-dominant hand

Venipuncture – Vacuum Tube Method, cont.

• Insert needle at a 15 degree angle• Stabilize the tube, never change hands during

the procedure• Fill each tube to exhaustion• As last tube fills to 3/4 s full, remove

tourniquet and remove tube• Place gauze or cotton at site and apply

pressure

Venipuncture – Vacuum Tube Method, cont.

• Apply co-ban• Place tubes in upright position after labeling• Remove gloves and sanitize• Chart the procedure• Appropriate sites for antecubital vacuum tube method of venipuncture

Butterfly Method of Venipuncture

• Called the Butterfly method because of the “wings” located between the tubing and needle

Butterfly Method of Venipuncture, cont.

• Used when veins are smaller, have a thin wall or are more likely to collapse

• Gauge of needle is 21 to 23• Length of needle is ½ to ¾ inch

• After collecting equipment and supplies:– Seat patient– Assess veins and locate vein for venipuncture

Butterfly Method of Venipuncture, cont.

• Follow procedure used for antecubital draw• Compress plastic wings together with bevel up• Insert at 15 degree angle to skin• After inserting, decrease angle to 5 degrees• Follow order of draw

Alternate Venipuncture Sites

• Inner forearm• Wrist area above the thumb• Back of the hand• Top of the foot

Types of Blood Specimens

• Clotted Blood – has no additives in tubes– Serum – required for most blood chemistry

studies• Obtained from clotted blood which is obtained from

tubes with no anticoagulants

• Whole blood – required for blood hematology studies such as a complete blood count– Plasma – obtained from tubes that have

anticoagulants to prevent clotting

OSHA Safety Precautions

• To avoid exposure to bloodborne pathogens:– Wear gloves– Avoid hand-to-mouth contact while working with

blood specimens– Wear a face shield or mask and eye protection– Perform all procedures in a manner to minimize

the splashing, spraying, or splattering of blood– Bandage cuts before gloving

OSHA Safety Precautions, cont.

– Sanitize hands after removing gloves– If exposure to blood occurs, wash with soap and

water immediately– If mucous membranes come in contact with blood

flush with water immediately– Do not break, bend, or shear contaminated

venipuncture needles– Do not recap contaminated venipuncture needles

OSHA Safety Precautions, cont.

– Locate sharps containers and keep close– Place blood specimens in containers that prevent

leakage during collection, handling, processing, storage, transport, and shipping

– Handle lab equipment and supplies properly– Do not store food in refrigerator where testing

supplies and specimens are stored– If exposed to blood – report incident to physician

or employer immediately

Order of Draw for Multiple Tubes

• Tubes must be drawn in a specific order as to not contaminate specimens

Problems Encountered with Venipuncture

• Failure to obtain blood– Can occur with obese or elderly patients– After two attempts ask for assistance

• Reasons for not getting blood:– Needle not inserted far enough– Needle inserted too far– Bevel lodged against the wall of vein

Hemolysis

• Hemolysis is the breakdown of blood cells– This can occur due to rough handling and can cause

inaccurate test results• To prevent hemolysis:– Store tubes at room temperature– Allow alcohol to air dry completely– Do not use small gauge needles to collect specimen– Handle tubes carefully– Do not shake or handle tubes

Fainting

• Some patients do not do well with venipuncture– Protect patient from injury– Place patient in a position that will promote blood

flow to brain– Notify provider for further treatment

Inappropriate Puncture Sites

• When not to use a potential site:– Scarred areas or sclerosed veins– Bruised areas– Burned skin– Adjacent to areas of infection– Edema– Avoid the arm on the same side of a radical

mastectomy

Preparation of Specimen

• If centrifuging is required:– Allow tube to stand upright 20 to 30 minutes at

room temperature• Do not let blood stand for more than one hour as this

causes leaching and will lead to inaccurate test results

– Centrifuge specimen for 10 minutes– Hold tube up to light to look for intact red blood

cells or hemolysis• If so, re-centrifuge specimen

Skin Punctures

• Used to obtain capillary blood specimens• Also known as a capillary puncture• Example of tests:– Hemoglobin– Hematocrit– Blood glucose– Prothrombin time

Skin Punctures, cont.

• Puncture sites:– Finger tip is preferred for adults– Earlobe as a back-up– Plantar surface of heal for infants, birth to one

year

Skin Puncture Devices

• Disposable semiautomatic retractable lancet devices

– Disposable lancets recommended by OSHA• Reusable semiautomatic retractable lancet

device

Skin Puncture Devices, cont.

• Depth of puncture– Adults: no deeper than 3.1 mm– Infants and children: no deeper than 2.0 mm

• If puncture is too deep, may penetrate bone– Could result in osteochondritis or osteomyelitis

Micro-collection Devices

• Specimens can be collected on various devices:– Reagent strips

– Capillary tubes

– Micro-collection tubes

Performing a Finger Puncture

• Use lateral part of tip of third or fourth finger– Do not use index finger because it is too callused– Do not use little finger because the amount of

tissue is not deep enough and could cause injury to bone

• Cleanse site with antiseptic wipe• Ask patient to remain still• Firmly grasp finger, select site, firmly press

lancet against site, and perform puncture

Performing a Finger Puncture, cont.

• Wipe away the first drop of blood, it is not suitable for testing

• Allow large drop to form– Can massage the finger, but do not squeeze, this

can cause inaccurate readings• Collect specimen• Apply pressure to ensure bleeding stops; apply

bandaid