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Carlo Mananquil
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HEMATOLOGY LABORATORY BLOOD COLLECTION OUTLINE • Venipuncture Equipment and Procedure o General Blood Collection Equipment & Supplies o Venipuncture Equipment o Methods of Venipuncture • Blood Collection Tubes o Blood Collection Tubes o Order of Draw • Vein Selection o Venipuncture Sit Selection o Major Veins for Venipuncture • Venipuncture Steps o Procedure for Venipunture o Requirement For Drawing Blood from Special Population • Pre-analytical Considerations in Phlebotomy o Areas to Avoid and Troubleshooting o Vascular Access Sites and Devices o Complications Associated with Blood Collection o Procedural Error Risk & Failure to Draw Blood o Factors Affecting Specimen Quality o Failure to Draw Blood • Capillary Puncture o Capillary Puncture o Equipment o Order of Draw for Capillary Puncture o Procedure for Selecting the Puncture Site & Collecting Capillary Specimens from Adults, Infants, & Children o Thick and Thin Blood Smear o Capillary Blood Gas o Neonatal Bilirubin o Newborn Screening VENIPUNCTURE EQUIPMENT AND PROCEDURE GENERAL BLOOD COLLECTION EQUIPMENT AND SUPPLIES • Blood Drawing Station/Phlebotomy area - usually utilized by outpatients • Phlebotomy chair - comfortable and arm rest should be adjustable • Equipment carrier/Phlebotomy collection tray - o Phlebotomy cart ▪ For STAT cases ▪ designed to be easily moved from laboratory to patient rooms ▪ larger capacity than phleb tray ▪ With waste disposal container o Phlebotomy cart • Gloves - should have good fit • Antiseptics - prevent sepsis; to clean puncture area o 70% Ethyl Alcohol - most commonly used • Disinfectants - to clean microorganisms/pathogens on surfaces, table tops • Hand-sanitizers - substitute for hand washing when hands are not visibly soiled • Gauze pads - to hold/apply pressure on puncture site to prevent bleeding • Bandages - to stop bleeding on the puncture site • Glass Slides - used in the laboratory for blood smears, clotting time tests • Sharps container - safe disposal of sharps • Biohazard bags - yellow bags; for infectious/contaminated materials • Marking pen - for labelling blood collection tube; should have non-smearing ink • Timer - for tests that are time-specific (bedside tests, clotting tests) VENIPUNCTURE EQUIPMENT • Vein-locating device - uses infrared light to locate and assess vein for safe access • Tourniquet - applied above the puncture site to raise veins by blocking blood flow • Needles - for withdrawing blood samples; should be always sterile and for single-use to prevent transmission of blood-borne pathogen • Evacuated tube system (ETS) PHLEBOTOMY NEEDLES • Used for withdrawing blood samples • Sterile and single use • Length : 1-1.5 inches • Gauge : 16-23 o 21 - standard for routine venipuncture o Inversely proportional to the bore (size of needle) o Lower gauge number - larger bore o Higher gauge number - smaller bore • 3 types : o Multi-sample - used for evacuated tube system ▪ 2 needles ▪ With rubber stopper - inserted to evacuated tubes ▪ Bare needle - inserted to the patient o Hypodermic - used in syringe system o Winged infusion set - usually used for IV transfusion; can be used in phlebotomy when veins are small and fragile
METHODS OF VENIPUNTURE SYRINGE SYSTEM • Used as an alternative method when drawing blood • Preferred method when drawing blood from patients with small or fragile veins. • Manual pulling of blood • Suction pressure on the vein can be controlled o Maintain proper pressure to prevent clotting/hemolysis • Routinely used: 2mL, 5mL and 10mL • Composed of: o Syringe needle – with plastic hub attached designed to fit onto the barrel. ▪ Hub can provide a sign to continue collection (blood in hub) ▪ Some have protection devices – hypodermic needle o Syringe – divided into graduated barrel and plunger ▪ Barrel – graduated into mL or cc ▪ Plunger – fits tightly within the barrel creating a vacuum when retracted EVACUATED TUBE SYSTEM (ETS) • Closed collection system • The most efficient and the most frequently used method for venipuncture • Blood is collected directly into the evacuated tube • It enables multiple tubes to be collected in a single venipuncture • Composed of: o Multi-sample needle – allows collection of multiple tubes during venipuncture; with two needles ▪ Bare needle - inserted to patient ▪ With rubber sleeve - inserted to evacuated tube o Tube holders - plastic cylinder with a small opening for a needle at one end and a large opening for tubes ▪ Secure multi-sample needle by screwing the threaded hub of the needle o Evacuated tubes – collection tubes with premeasured vacuum that automatically draws the volume of blood indicated in the tube label. ▪ Can be an additive or non-additive tube • Procedure 1. Screw needle into the tube adapter 2. Insert the first tube to be collected into the tube adapter; do not fully puncture the tube to prevent release of vacuum 3. Insert the needle to the vein of choice 4. Push the tubes up to the adapter guideline 5. Wait until blood stops from flowing inside the tube then safely remove ▪ Follow the order of draw BUTTERFLY SYSTEM • Winged infusion set • Used for IV fluid infusion and venipuncture for very small and fragile vein (pediatrics and geriatrics) • Has short needle with a plastic part resembling butterfly wings • Length of needle: ½ - ¾ inch • With long tubing with: o Luer fitting – syringe o Luer adapter – ETS BLOOD COLLECTION TUBES BLOOD COLLECTION TUBES • Also called evacuated tubes/Vacutainer • May contain none to more than one additives depending on the test ordered. • Color-coded depending on the additive present • Forms of additives: Liquid, Spray-dried, or Powdered • Additive Categories: o Anti-coagulants (Blood thinners) – chemical substances that prevents blood clots. EDTA, etc. o Special-use anticoagulant - for special tests (blood banking, blood cultures) o Antiglycolytic agents – prevent breakdown of glucose by blood cell or glycolysis ▪ Important in delayed testing for glucose o Clot activators – enhance coagulation, thrombin, glass, silica particles o Thixotropic gel separator – inhibits cellular metabolism of substances by moving in between the cells and serum/plasma o Trace element-free tube – few of trace elements contamination; for trace element determination
ORDER OF DRAW • A special sequence of tube collection that reduces the risk of specimen contamination by microorganisms and additive carry over ORDER OF DRAW TUBE STOPPER COLOR 1. Blood culture tubes Yellow (SPS) 2. Coagulation tubes Light Blue Top 3. Serum tube with no additives Red (Glass) 4. Serum tube with additives, SST Red/Black, Gold, Red/Gold 5. Plasma Separator Tubes Heparin Light Green, Green/Gray Green 6. EDTA tubes Plasma Preparator Tubes Oxalate/Fluoride tubes Lavender/Purple, Pink Pearl Top Gray top • Blood culture is first to reduce contamination • Coagulation tube is second to have coagulation unaffected because additives from other tubes may affect coagulation • Serum tube with additives • EDTA is last because it may affect other tests VEIN SELECTION VENIPUNCTURE SITE SELECTION • Site Selection: o Palpation – locating veins by sight and touch (rolling of fingers on the site) o Antecubital area/fossa – elbow pit; triangular area anterior to the elbow; preferred venipuncture site o Other arm and hand veins - alternative site o Leg, ankle, and foot veins - alternative site MAJOR VEINS FOR VENIPUNCTURE • Antecubital Fossa o the site of major veins used for venipuncture o First choice for routine venipuncture because there are several major arm veins called antecubital veins o the veins are also close to the surface thus easily palpable and penetrable by needle. ANTECUBITAL VEINS • Two Patterns: • H-shaped o Occurs in 70% of population; most common o Median Cubital Vein – preferred venipuncture site. The easiest to access and least painful to puncture ▪ Well-anchored vein o Cephalic Vein – second choice for venipuncture. It is harder to palpate but usually better when drawing blood for obese patients. o Basilic Vein – last choice for venipuncture. It is not well anchored and more painful to puncture ▪ Closer to nerve endings • M-shaped o Median vein – first choice. Safest and less painful o Median cephalic – second choice. Less likely to roll o Median basilic – last choice. More painful
OTHER VEINS OF CHOICE • Other arm and hand veins o Only used if antecubital area are not accessible o Only veins at the back of the hand are used. They are smaller in size, thus more painful. o The underside of the wrist is never used as venipuncture site ▪ The veins in this area are close to arteries • Leg, ankle and foot veins o should not be used in venipuncture without permission of a physician o a risky venipuncture which can result in embolism VENIPUNCTURE STEPS PROCEDURE FOR VENIPUNCURE • Step 1: Review and Accession the Test Request o Status Designations, Status Priorities, & Procedure for Each Status Designation o Reviewing Information & Request o Status Designations - priority designation (STAT, emergencies) • Step 2: Approach, Identify and Prepare the Patient o Proper “Bedside Manner” and handling special situations associated with patient contact o Importance of proper patient identification ▪ Most critical step o Patient preparation for testing - discuss procedure • Step 3: Verify the Patient’s Diet Restrictions and Latex Sensitivity o Verifying fasting and other diet requirements • Step 4: Sanitize Hands • Step 5: Position the patient, apply the tourniquet, and ask patient to make a fist. • Step 6: Select vein, release tourniquet, and ask patient toopen fist o Tourniquet application ▪ Length of time - <60 seconds; longer application may cause hemoconcentration • Hemoconcentration - cause erroneous result ▪ Distance - 3-4 inches above the puncture site • Step 7: Clean and air-dry the site • Step 8: Prepare the Equipment and Put on Gloves o Steps in equipment preparation for different venipuncture procedure ▪ Evacuated Tube System (ETS) ▪ Syringe System ▪ Winged Infusion Set (Butterfly System) • Step 9: Reapply the tourniquet, Uncap, and Inspect the Needle • Step 10: Ask the patient to remake a fist, anchor the vein, and insert needle o Always inspect the needle and do not hesitate to replace needle when needed o Pull skin and insert needle swiftly (to lessen pain) • Step 11: Establish blood flow, release tourniquet, and ask patient to open the fist • Step 12: Fill, remove, and mix the tubes in order of draw or fill the syringe • Step 13: Place gauze, remove needle, activate safety feature, and apply pressure o Remove needle safely and swiftly o Applying pressure allow cessation of blood leakage • Step 14: Discard the collection unit, syringe needle, or transfer device • Step 15: Label the tubes o Patient's Complete Name o Date of Birth o ID Number (If Applicable) o Date and Time of Collection o Initials of Phlebotomist o Additional Information (eg: fasting) • Step 16: Observe special handling instruction • Step 17: Check patient’s arm and apply bandage • Step 18: Dispose contaminated materials • Step 19: Thank the patient, remove the gloves, and sanitize hands • Step 20: Transport the specimen to the laboratory REQUIREMENT FOR DRAWING BLOOD FROM SPECIAL POPULATION • Pediatric puncture o Infants, newborns - do not have large or palpable veins • Geriatric venipuncture o Elder people have less anchored veins o Gentle handling due to sensitive/fragile skin o Geriatric patients are more susceptible to hemolysis/hematoma • Long-term care patient o Dialysis Patients - avoid site with fistula o Long-Term Care Patients - gentle handling o Home-Care Patients o Hospice Patients - palliative patients (end-of-life care) ▪ More gentle handling PRE-ANALYTICAL CONSIDERATIONS IN PHLEBOTOMY AREAS TO AVOID AND TROUBLESHOOTING • Burns, Scars & Tattoos o Burned area - may be painful o Scarred area - stiff due to collagen buildup; harder to puncture o Tattooed area - may contaminate area with tattoo ink
• Damaged Veins - avoid these areas • Edema - area may contaminate blood with interstitial/edematous fluid • Hematoma - area may have clotted blood • Mastectomy - collect blood from opposite side of the mastectomy side o Example: collect from right arm when mastectomy is performed in left side • Obesity o Harder to collect blood due to harder palpation of vein o Deep veins negatively affect palpation and selection of site o Cephalic Cubital vein is preferred VASCULAR ACCESS SITES AND DEVICES • Arterial Line o Thin catheter inserted in arteries o Avoid application of tourniquet in site with arterial line • Arteriovenous Shunt or Fistula o Used for hemodialysis; passageway connecting vein and arteries o Puncturing fistula may cause prolonged bleeding (clots are not formed around fistula) • Blood Sampling Device o Used to avoid needlesticks o Provide convenience in blood collection • Heparin or Saline Lock o IV catheters attached to stopcock; provide access to drug administration o Usable for 48 hours o Not usually recommended for blood collection; additives may affect results • Intravenous (IV) Sites o Tube inserted into vein to administer medications or other liquids o Collect blood from opposite arm of the arm with IV site o Arm with IV site may have contaminated blood that may affect results o Collect blood from below IV site o Discard first 5 ml of blood collected to avoid contamination • Central Venous Access Devices (CVADs) o Used for administering fluids o Central Venous Catheter o Implanted Port o Peripherally Inserted Central Catheter (PICC) COMPLICATIONS ASSOCIATED WITH BLOOD COLLECTION • Allergies to Equipment and Supplies o Allergies to latex, antiseptic, adhesive o To prevent hypersensitivity reaction • Excessive Bleeding o Complications to patients undergoing anticoagulant/aspirin therapy o If bleeding continues for more than 5 minutes, call a physician • Fainting o Continuous loss of consciousness o Ask patient to lie down when prone to fainting • Nausea & Vomiting o Halt procedure until patient gets better • Pain o Inevitable in blood collection o During extreme pain and numbness, remove needle and apply ice to the site. • Petechiae o Small red/purple spots during blood collection o A result from platelet complications o Apply pressure to the site after removing needle • Seizures or Convulsions o Rarely experienced o If experienced, remove tourniquet and needle and apply pressure to the site. o Restrain the patient in a manner to prevent injury PROCEDURAL ERROR RISK & FAILURE TO DRAW BLOOD • Hematoma Formation o Apply pressure and discontinue drawing blood o If there is swelling, apply cold compress to the site • Iatrogenic Anemia o Condition of blood loss due to frequent blood collection o Pediatric patients are prone • Inadvertent Arterial Puncture o Accidental puncture of vein o Determined by rapid blood flow & brightly colored blood o May cause hematoma formation • Infection o Prevent infection by asking patient to keep bandage for 15 minutes o This is to ensure clotting in the puncture site • Nerve Injury o Occur when accidental hitting of nerves o May result in loss of movement/control in limbs o Apply ice pack initially and follow warm compress to the area • Reflux of Anticoagulant o When there is blood back flow due to evacuated tube in a downward position o Cause contamination of blood with tube additive • Vein Damage o Avoided by following proper technique and avoiding blind probing (blind fishing) FACTORS AFFECTING SPECIMEN QUALITY • Hemoconcentration o Decrease in blood plasma due to prolonged tourniquet application o Cause erroneous results • Hemolysis o Rupture of RBC o RBC contents are expelled into the whole blood affecting erroneous results • Partially Filled Tube or Short Draw o Inability to satisfy blood to additive ratio o Greatly affect result • Specimen Contamination o Usually happen during handling/transport • Wrong or Expired Collection Tube o Wrong collection tube may contaminate succeeding specimens and affect results o Expired collection tubes have no vacuum and have unsure quality of additive
FAILURE TO DRAW BLOOD • Causes: o Needle not inserted not far enough o Bevel partially out of skin o Bevel partially into vein o Bevel partially through vein o Bevel against vein wall o Needle beside vein o Undetermined position o Collapsed vein o Tube vacuum CAPILLARY PUNCTURE CAPILLARY PUNCTURE • aka Dermal puncture • Method of Choice for collecting blood from infants and children below 1 year old. • These are blood specimen that comes from capillary, arterioles, and venules. • Composition : o Arterial Blood o Venous Blood o Interstitial and Intracellular fluids • Concentration differences: o Glucose : higher than venous blood o Potassium , total protein and calcium : Lower than venous blood INDICATIONS • Infants (<1 y/o) • Used on adults and older children, if: o Burned or scar patients o Patient receiving chemotherapy o Patient with thrombotic tendencies o Geriatric with fragile veins o Patient with inaccessible veins o Obese patients o Apprehensive patients o Patients requiring home glucose monitoring (POCT) EQUIPMENT • Lancet/Incision Devices • Laser Lancet • Microcollection Container - similar to blood collection but with smaller volume • Microhematocrit tubes and Sealants o Heparinized - red o Non-heparinized - blue o Sealant - to seal one end • Microscope Slides • Warming Devices o Heel warmers, warm cloth • Capillary Blood Gas (CBG) Equipment ORDER OF DRAW FOR CAPILLARY PUNCTURE • Important as platelet has tendency to accumulate at the site of wound. Order of Draw Additives Inversion/mixing Capillary Blood Gas Heparin Rotate between palms Blood Smears (Glass Slide) N/A N/A Lavender top EDTA 10 Heparinized Lithium heparin 10 Plasma Separator Tubes Lithium heparin with gel separator 10 Oxalate/Fluoride Tubes Sodium fluoride with Potassium oxalate 10 Serum tube with additives Clot activator 5 Serum tube without additive N/A 0 Newborn Screening Use spot/filter cards 0 • EDTA is first to ensure appropriate volume PROCEDURE FOR SELECTING THE PUNCTURE SITE & COLLECTING CAPILLARY SPECIMENS FROM ADULTS, INFANTS, & CHILDREN • Step 1. Review and Check Accession Test Request • Step 2. Approach, identify, & Prepare the Patient • Step 3. Verify Diet Restrictions & Latex Sensitivity • Step 4. Sanitize & Put on Gloves • Step 5. Position the Patient • Step 6. Select the Puncture/Incision Site • Step 7. Warm the Site (if necessary) • Step 8. Clean & Air-Dry the Site • Step 9. Prepare the Equipment • Step 10. Puncture the Site & Discard the Lancet
• Step 11. First Blood Should be Wipe Away • Step 12. Fill & Mix Tubes or Containers in the Order of Draw • Step 13. Place the gauze & Apply Pressure • Step 14. Label Specimen & Observe Special Hnadling Instructions • Step 15. Check the Site & Apply Bandage • Step 16. Disposed used materials • Step 17. Thank patient, remove gloves & Sanitize Hands • Step 18. Transport Specimen to the Laboratory THICK AND THIN BLOOD SMEAR THIN BLOOD SMEAR PREPARATION • Used to appearance of blood cells for diagnostic purposes: o Blood cell abnormalities o Identification and differential quantification of WBC o Platelet estimate count • Procedure: 1. Place one drop of blood near one end of a glass slide 2. Use another slide to spread the drop of blood into thin smear 3. Air dry then stain. THICK BLOOD SMEAR PREPARATION • Used for quantitative malaria determination • Procedure: 1. Place one drop of blood on the center of the slide 2. Place a drop of water and mix 3. Allow to air dry then stain • Water de-hemoglobinizes RBC CAPILLARY BLOOD GAS • Arterial blood – preferred sample for blood gas analysis and pH determination • Capillary blood is only used among newborns and infants. • Arterialize capillary blood by warming the site prior to collection (40-42 ̊C for 3-5 minutes) • Microcollection tube: Heparinized • Sample are place in ice slurry and transported to the laboratory immediately. NEONATAL BILIRUBIN • Bilirubin – a light sensitive analyte that imparts dark yellow discoloration in the blood, skin and eyes. o Commonly performed among newborn o Bilirubin is critical for infant survival and mental health • Hyperbilirubinemia (newborn) – Jaundice o Dark yellow discoloration of eyes & skin o Hemolytic disease of the newborn o Underdeveloped liver of premature newborns • Microcollection tubes : o Amber-colored tubes (for light sensitivity) o Covering tubes with carbon paper. NEWBORN SCREENING • Blood is collected by heel prick and placed on a special filter paper. • Directly apply drop of blood to the special paper. • Done within 48 hours from birth • Importance : o Newborn may appear normal at birth. o Metabolic disorders may be detected before clinical symptoms manifest. o Some detected disorders may cause mental retardation o To start treatment immediately
Hematology Lab - 01 Blood Collection
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