Prelim Hema Lab PDF

HEMATOLOGY 1 LAB (Prelims) → Specimen collected in correct order and properly labelled INTRODUCTION → Properly identified patient HEMATOLOGY...

HEMATOLOGY 1 LAB (Prelims) → Specimen collected in correct order and properly labelled INTRODUCTION → Properly identified patient HEMATOLOGY → Correct anticoagulants and preservative used → A branch of medicine that primarily focuses on → Specimens properly mixed by inversion the study of blood and blood → Specimen not hemolyzed disorders/diseases. → Fasting specimens collected in timely manner → Came from the Greek word “Haima” which → Timed specimens drawn at correct time means blood. SPECIMEN REJECTION BLOOD → Unmatched request and specimen → Major body fluid. → Unlabeled or incorrect labelling → Slightly alkaline = pH: 7.4 → Hemolyzed → Average specific gravity = 1.055 → Wrong collection tube and time → Total volume = 5.6 L (7-8% body weight) → Contaminated and lipemic specimen 45% formed elements PHLEBOTOMY 55% fluid portion (90% water; 10% proteins, carbohydrates, lipids, hormones, The process of collecting blood from the vessels for enzymes, waste products, vitamins) laboratory tests. BLOOD CELL FAMILIES When collecting blood, safety precautions must be → RED BLOOD CELLS (ERYTHROCYTES) observed. Makes Hgb, transports CO2 & O2. Phlebotomist must maintain good health and → WHITE BLOOD CELLS (LEUKOCYTES) hygiene, attitude, communication skills, and For body defense. bedside manner. → PLATELETS (THROMBOCYTES) Patient has the right to refuse (if kids, talk to the For body response against bleeding. parents). FUNCTIONS OF BLOOD PHYSIOLOGIC FACTORS 1. Respiratory → POSTURE – shift of body water from the 2. Nutritional vessels to interstitial spaces (lying down = 3. Excretory promote HEMODILUTION; standing up = 4. Buffering action promote HEMOCONCENTRATION). 5. Body temperature → DIURNAL RHYTHM – substances that 6. Transports hormones increases or decreases. 7. Immunity → BASAL STATE – state of the body in early 8. Hemostasis – protection from bleeding morning. What happens in the HEMATOLOGY SECTION? → EXERCISE – increased of various → COMPLETE BLOOD COUNT (CBC) biochemicals. 1. RBC count → STRESS – anxiety and extreme stress can 2. WBC count increase WBCs. 3. Hgb → DIET – body’s response to fasting. 4. Hct → SMOKING – increases WBC and cortisol and 5. RBC indices increases Hgb. 6. *Platelet count TYPES OF PHLEBOTOMY → VENIPUNCTURE – the most common SPECIMEN COLLECTION → Arterial Puncture → Skin Puncture Proper handling of specimen starts with test request and ends when the specimen is finally tested. VENIPUNCTURE PATIENT IDENTIFICATION – most critical step → Medtech must ask the patient’s name and/or MATERIALS NEEDED: check the identification card attached to the 1. SYRINGE patient. Needle – 1-1.5 inch in length; gauge: 19, → Ask the nurse or doctor if the patient is unable 20, 21; angle: 15-30°. to give his name. 2. TOURNIQUET – provides barrier against → Refuse collection if the patient has a wristband venous blood flow to help locate vein and error. stretches the wall so they become thinner and Specimens for routine testing should be delivered easier to pierce. to the lab within 45 minutes to 1 hour of collection. Applied 2-4 inches/7.5-10 cm above site REQUIREMENTS FOR A QUALITY SPECIMEN Applied for no longer than 1 minute → Patient properly prepared for draw Blood pressure cuff – 60 mmHg  Prolonged application may cause PROCEDURE: hemoconcentration. 1. Apply tourniquet and locate vein. 3. DISINFECTANT – 70% alcohol 2. Disinfect site of choice. Skin cleanser for sensitive skin: 3. Puncture observing the right angle. CHLORHEXIDINE GLUCONATE 4. Collect blood and follow order of draw. SITES OF COLLECTION 5. Remove tourniquet. → 3 primary veins: MEDIAN, CEPHALIC, 6. Place cotton and remove needle swiftly. BASILIC. 7. Apply pressure. → Other sites: Veins on the dorsal side of wrist ORDER OF DRAW and hand. → SYRINGE Blood culture Other sterile tubes Light blue Serum separator Green Lavender Grey Yellow Red → ETS Yellow (Culture) Blue Red Green Lavender Grey COMMON STOPPER COLORS, ADDITIVES, AND DEPARTMENTS INVOLVED STOPPER INTRAVENOUS THERAPY – should be avoided if ADDITIVE DEPARTMENT(s) COLOR possible (use the other arm). Light blue - Sodium citrate Coagulation → If no choice: tourniquet and collection should be Chemistry, blood below the catheter site. Red (glass) - None bank, serology / → Always inform the nurse to stop IV for 2-5 immunology Red (plastic) - Clot activator Chemistry minutes. Red/light grey N/A (discard tube → Discard the first 5 mL of blood collected. - Non-additive (plastic) only) → Note in the request that IV collection was done. Red/black (tiger) - Clot activator and gel SITES TO BE AVOIDED: Gold Chemistry separator 1. Edematous sites Red/gold 2. Burned Green/grey, - Lithium heparin and Chemistry Light green gel separator 3. Damaged - Lithium heparin 4. Scarred Green Chemistry - Sodium heparin 5. Occluded veins Lavender Hematology - EDTA 6. Mastectomy site Pink Blood bank 7. Dialysis patients (cannula & fistula) - Sodium fluoride and METHODS potassium oxalate Grey - Sodium fluoride and Chemistry → Syringe EDTA → ETS - Sodium fluoride → Butterfly (Winged Infusion Set) Orange - Thrombin Chemistry Grey/yellow - None (red label) - EDTA (lavender label) Royal blue Chemistry - Sodium heparin (green label) Tan (glass tube) - Sodium heparin Chemistry Tan (plastic) - EDTA - Sodium polyanethol Yellow Microbiology sulfonate (SPS) - Acid citrate dextrose Blood bank / Yellow (ACD) immunohematology  PHLEBOTOMY ERRORS CAUSE OF HEMOLYSIS 1. Small needle was used 2. Pulling the plunger too fast 3. Forcing the blood to an evacuated tube 4. Shaking the tube vigorously 5. Collecting blood before alcohol dries 6. Expelling blood vigorously TUBE LABELS 1. Patient’s first and last name 2. Identification number SPECIMEN FOR HEMATOLOGY SECTION 3. Date and time of collection 4. Identification of phlebotomist Ethylenediaminetetraacetic acid (EDTA) → Chelates calcium SKIN PUNCTURE → Used for cell counts and cell morphology Performed to collect capillary blood. → Follow 8x inversion Done if: burned, fragile veins, reserved veins, or If anticoagulated, it will produce PLASMA; if not, it only small amount is needed. will produce SERUM. Capillary Blood = Venous + Arterial + Tissue Fluid Materials: HEMOGLOBIN → Lancet HEMOGLOBIN → Disinfectant (70%) → Single most common complex organic → Cotton molecule in vertebrates. SKIN PUNCTURE SITES: → Discovered by FELIX SEYLER in 1862. → NEWBORNS – medial or lateral surface of → 35% of the RBC. plantar side of the heel. → “Oxygen-binding pigment.” → ADULTS – middle or fourth finger of non- → A mature red cell contains about 3 million dominant hand. molecules of hemoglobin. PROCEDURE: → A protein with a MW (molecular weight) = 64, 1. Warm site to increase blood flow. 500 Daltons. 2. Disinfection of the site. → Binds O2 and CO2. 3. Puncture – should be PERPENDICULAR to the The tissues has the lowest oxygen tension fingerprint (allows blood to run down the finger) of 20 mmHg pressure. and puncture should not be more than 2 mm in The lungs has the highest oxygen tension depth. of 100 mmHg pressure. 4. Wipe the first drop using clean cotton (removes dead skin cells and tissue fluid, and facilitate HEMOGLOBIN IN NORMAL ADULT BLOOD free flow of blood). 5. Collect blood. 1. Hemoglobin A = 94.5% (2 alpha and 2 beta) 2. Hemoglobin A2 = 3.5% (2 alpha and 2 delta) 3. Hemoglobin F – 2% (2 alpha and 2 gamma)  → Measures all forms of hemoglobin except sulfhemoglobin. → Reagent: DRABKIN’S REAGENT Potassium ferricyanide – converts ferrous to ferric iron. Non-ionic detergent – improve lysis of RBC and lowers turbidity. → Read at 540 nm. → TURBIDITY – can cause false increase in hemoglobin concentration. COMPOSITION Causes of Turbidity: 2 pairs of polypeptide chains - Lipemia 2,3 Diphosphoglycerate - Elevated WBC count 4 Heme groups - Hemoglobin S and C → PROCEDURE: ABNORMAL HEMOGLOBIN a. Place 5.0 mL of Drabkin’s reagent in a clean and labeled test tube. 1. CARBOXYHEMOGLOBIN b. Add 0.02 mL (1 drop) blood of well-mixed → With ferrous form of iron (Fe) and carbon whole blood. monoxide (CO). c. Mix solutions well and allow to stand at RT → Irreversible (room temperature) for at least 10 minutes. → CO has 218x greater affinity to hemoglobin at d. Read absorbance at wavelength 540 nm. 37°C. e. Record readings. → Elevated in heavy smokers. 2. SPECIFIC GRAVITY METHOD – “COPPER → Cannot bind and carry O2. SULFATE” → Tests: → Employs copper sulfate with known specific Spectrophotometry gravity (1.052 and 1.054). Gas Chromatography → A drop of blood is added to the solution. 2. METHEMOGLOBIN (Hi) → If the drop sinks within 15 seconds, the → “Ferrihemoglobin”, “oxidized hemoglobin”, hemoglobin is normal (>12.5 g/dL). “hemoglobin” → With ferric form of Fe and an oxidizing agent. → Chocolate-brown in color. → Reversible because methemoglobin is unstable. → e.g. of Oxidizing Agents: Sulfonamides Nitrates and Nitrites Potassium ferricyanide Potassium permanganate 3. SULFHEMOGLOBIN → Irreversible → During oxidation, sulfur is incorporated into the heme rings of Hgb, forming a green hemochrome. → May be due to: Prolonged constipation Sulfadrugs Trinitrotoluene Bacteremia Enterogenous cyanosis → Tests: Spectrophotometry HEMOGLOBIN METHODS 1. CYANMETHEMOGLOBIN → “Ferrihemoglobin cyanide”, “Hemoglobin cyanide method” → Reference method