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72 Cards in this Set
- Front
- Back
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What kind of blood specimen?
- Tube contains anticoagulant - Tube must stay well mixed |
Whole Blood
- Contains cells (RBCs, WBCs, PLTs) and plasma |
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What kind of blood specimen?
- Blood is allowed to clot for ~20 minutes - Blood is centrifuged - What is the clear portion at the top? Does it contain fibrinogen or not? |
Serum
- NO fibrinogen |
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What kind of blood specimen?
- Whole blood is centrifuged (anticoagulant is used) - What is the clear portion at the top? Does it contain fibrinogen or not? |
Plasma
- YES, it contains fibrinogen |
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A combination of venous blood, arterial blood and tissue fluid obtained through a skin puncture
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Capillary blood
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(2) Ways Specimen Reliability can be compromised
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1. Inappropriate method of collection
2. Mishandling of specimen after collection |
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Rupture of RBCs resulting in plasma/serum appearing pink-red due to release of hemoglobin
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Hemolysis
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What causes hemolysis?
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Traumatic phelobotomy (or in a rare case, intravascular disease and RBC fragility)
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Specimen has a cloudy turbid appearance due to the presence of lipids
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Lipemia
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What interferes with chemical analysis in hemolysis?
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Release of intracellular contents- K+, LDH, etc.
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What interferes with chemical analysis in lipemia?
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Chylomicron interference
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In order to obtain the proper ratio of blood to anticoagulant, tubes should be filed until the vacuum is exhausted
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Improperly filled tubes
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Improper antiseptic cleaning of venipuncture site
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Specimen contamination
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(4) Specimen Handling Requirements
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1. Fasting
2. Timed 3. Ice 4. Protection from light |
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Color coded tubes are universally color coded for what (2) reasons?
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1. The type of specimen that will be obtained (plasma, serum, whole blood)
2. The type of additive the tube contains |
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What color tube should always be drawn first? What color tube should always be drawn last?
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First: red/marbled (gel separator/clot activator)
Last: lavender (EDTA) * Any red (all red/some red) tubes contain no additives and will coagulate; this is used to get serum |
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What is the standard gauge of an adult phlebotomy needle?
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21 gauge
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What is the standard gauge of a pediatric phlebotomy needle?
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22 gauge
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What is the standard length of a phlebotomy needle?
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1.5 inches
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What is the gauge and length of the most commonly used needle?
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21 gauge by 1.5 inch needle
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As the gauge of the needle gets bigger, does the diameter of the needle increase or decrease?
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Decrease!
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What (3) primary veins are involved in a venipuncture procedure? Which is the most commonly used?
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1. Cephalic
2. Basilica 3. Median Cubital (this one is used most commonly) |
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What are two reasons the tourniquet should not be left on longer than 1 minute?
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1. Hemoconcentration
2. Patient discomfort |
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Increase in local cellular release of metabolic waste products
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Hemoconcentration
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Patient identification is extremely important when performing a venipuncture. What should you have the patient state?
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Full name and identification number
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What information needs to be on the tube when labeling after a venipuncture?
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1. Full name
2. Identification number (we used patient's birthday in class) 3. Date 4. Time |
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What is the carrier protein for oxygen and CO2 (~95% of RBC protein?
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Hemoglobin
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What is most sensitive when screening for anemia?
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Hemoglobin
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Normal Values of hemoglobin for males and females
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Males: 13.2 0 17.3 g/dl
Females: 11.7 - 15.5 g/dl |
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The percentage of blood volume occupied by RBCs (packed cell volume)
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Hematocrit
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Beside hemoglobin, what is used to screen for anemia?
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Hematocrit
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Calculation for Hematocrit
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[Height of total column of blood (plasma and cells) divided by the height of RBCs] multiplied by 100
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Average percentages of hematocrit for males and females
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Males: 39 - 49%
Females: 35- 45% |
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Measures how far the RBCs fall (in mms) in one hour's time
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Erythrocyte Sedimentation Rate - ESR
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What is a non-specific indicator of inflammation?
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ESR
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Normal ESR values for males and females
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Males: 0 - 15 mm/hr
Females: 0 - 20 mm/hr |
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RBCs are negatively charged and repel each other
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Zeta potential
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With the breakdown of the zeta potential, the RBCs stack up like coins
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Rouleaux formation
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Phenotype: A
What is the genotype? What antigens are present? What antibodies are present? |
Genotype: AA, AO
Antigen: A Antibody: Anti-B |
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Phenotype: B
What is the genotype? What antigens are present? What antibodies are present? |
Genotype: BB, BO
Antigen: B Antibody: Anti- A |
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Phenotype: AB
What is the genotype? What antigens are present? What antibodies are present? |
Genotype: AB
Antigens: A and B Antibodies: NONE |
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Phenotype: O
What is the genotype? What antigens are present? What antibodies are present? |
Genotype: OO
Antigens: NONE Antibodies: Anti-A and Anti-B * There is NO O antigen * |
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When transfusing blood, what are you giving? What is not being given?
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- You are giving packed RBCs
- You are NOT giving plasma which contains any of the anti-bodies |
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What do you need to consider before transferring blood to determine compatibility?
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ANTIGENS on the donor's blood and ANTIBODIES on the recipients blood
It is the recipient's antibodies that react with the donor's RBC antigens which causes RBC hemolysis if the blood is not compatible |
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Phenotype: Rh positive (D)
What is the genotype? What antigens are present? What antibodies are present? |
Genotype: DD, Dd
Antigens: D Antibodies: NONE |
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Phenotype: Rh negative (d)
What is the genotype? What antigens are present? What antibodies are present? |
Genotype: dd
Antigen: NONE Antibodies: Anti-D (IgG) * The d gene represents the lack of the D antigen; there is NO d antigen! * |
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What method of blood collection is ideal for infants and children under age 2?
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Dermal puncture procedure
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Why would you use dermal puncture procedure in adults?
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- Inability to find a vein
- Burned or scarred patients - Geriatric patients with fragile veins - Patients receive chemotherapy - When only a small sample is needed |
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Composition of capillary blood?
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Venous, arterial and interstitial fluids
* This should always be noted on the report * |
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What is the most common test used to evaluate circulating blood cells?
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CBC
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Increase in the number of circulating WBCs greater than 11,000/mm3
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Leukocytosis
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Decrease in the number of circulating WBCs less than 4,000/mm3
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Leukopenia
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WBC Count from CBC
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Blood is sampled directly from tube and mixed with a lysing reagent which removes RBCs from solution and strips WBCs of cell membrane
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WBC nuclei are counted how for a WBC count?
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Counted by electrical impedance or light scattering methods
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RBC Count from CBC
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Blood sampled directly from tube is diluted and cells counted by electrical impedance or light scattering methods
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Increase in total number of circulating RBCs
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Erythrocytosis
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Decrease in total number of circulating RBCs is consistent with what?
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Anemia; also H & H
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Hgb from CBC
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Blood is sampled directly from tube. Reagent is added to lyse RBCs and to form cyanmethemoglobin and read directly by it's ability to abosrb light
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Hct from CBC
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Calculated parameter based on RBC and MCV values
Hct = (MCV x RBC)/10 |
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The average volume of red cells
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MCV (Mean Cell Volume)
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The weight of hemoglobin in the average RBC
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MCH (Mean Cell Hemoglobin)
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The concentration of hgb per unit volume of RBCs expressed as a %
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MCHC (Mean Cell Hemoglobin Concentration)
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A measure of the degree of uniformity of size of RBC
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RDW (Red Cell Distribution Width)
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PLT count from CBC
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Blood is sampled directly from the tube; platelets are counted from RBC dilution
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What produces platelets?
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Megakaryocytes which reside in bone marrow
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Increase number of platelets
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Thrombocytosis
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Decrease number of platelets
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Thrombocytopenia
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Measures the average volume (size) of platelets
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MPV (Mean Platelet Volume)
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Measure of the degree of uniformity of size of platelets
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PDW (Platelet Distribution Width)
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Gives relative numbers of lymphocytes, monocytes, neutrophils, eosinophils and basophils
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Automated Diff
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Variations in the size of RBCs due to a pathological condition
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Anisocytosis
Not a specific finding, generally indicates a change in marrow function (increased RDW) |
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Refers to RBCs that are slightly basophilic (bluish tint)
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Polychromic
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Variations in the shape of the RBC
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Poikilocytosis
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