ADVIA® 360 Hematology System Technologies Online Training

Welcome to the ADVIA® 360 Hematology System Technologies Online Training course. The ADVIA 360 Hematology System is a fully-automated, quantitative, multi-parameter, bench-top hematology analyzer, designed for the in vitro diagnostic testing of anti-coagulated human whole blood. The parameters include white blood cell (leukocyte), red blood cell (erythrocyte) and platelet counts, hemoglobin concentration, mean corpuscular hemoglobin, and a 3-part leukocyte differential including both a count and percentage of lymphocytes, mid-size cells, and granulocytes. In this course you will learn about the different measurement methods used to determine sample results along with the measurement sequence. Select Next to continue. Upon successful completion of this course, you will be able to: Describe how the system uses photometric light absorbance to measure the hemoglobin concentration Explain how the system uses volumetric impedance to determine the number and volume distributions of cells Describe how the system determines the 3-part white blood cell differential analysis Explain the measurement sequence of the system's analysis process Select Next to continue. Congratulations. You have completed the ADVIA 360 Hematology System Technologies online training course. Listed below are the key points that have been presented. Take time to review the material before you proceed to the final quiz. Download and print a copy of the Course Review. Describe how the system uses photometric light absorbance to measure the hemoglobin concentration A lysed blood sample (WBC) dilution is analyzed for hemoglobin concentration based on its stable chromogen content The lyse reagent causes the RBCs to release cellular hemoglobin The HGB concentration is measured by taking a photometric reading across the WBC chamber HGB is calculated as the difference between a blank and a sample measurement with, and without, illumination to reduce the effect of liquid refraction and incident light Explain how the system uses volumetric impedance to determine the number and volume distributions of cells This method determines the number and volume distributions of cells The system detects and measures changes in electrical impedance when particles that are suspended in a conductive liquid pass through a small aperture There is a constant direct current that flows between the electrodes on both sides of the aperture Each cell passing through the aperture causes changes in the impedance of the conductive diluted blood sample This impedance change is detected by the electronics and converts the change into an electrical pulse The number of pulses therefore is proportional to the number of particles in the diluted sample Intensity of each pulse is proportional to the volume of the particle The volume distribution diagrams of the particles are displayed as the WBC, RBC, and PLT histograms measured in fL units Electronic discrimination by size allows separation of PLTs, RBCs, and WBCs Discriminators are indicated by dotted vertical lines on the histograms Describe how the system determines the 3-part differential analysis  The WBC lytic process allows the system to simultaneously count and size-differentiate the WBCs There are three elements that determine where the different cell types fall in the WBC histogram: Chemical formulation and concentration of the lytic reagent The lyse reagent controls how different WBC types are differentially lysed The concentration of the lyse reagent controls the rate of lysing (shrinking), and the time of incubation Type and maturation of the cells present for analysis Different WBC types and grades of maturation have different sensitivities to the lyse reagent Lymphocytes are the most sensitive type Band neutrophils, immature granulocytes, and blasts have a cell membrane that is sensitive to the lyse process which classifies them as mid-size cells, at the time these cells are counted and sized Time window in the lytic process During this time window cells are counted and sized As this process is a dynamic reaction, the count and sizing-time window used during the lytic process has been optimized for performance Explain the measurement sequence of the system's analysis process The sampling needle moves into the sample vial and aspirates 100µL of EDTA anti-coagulated whole blood sample 25µL of this sample is separated in the sampler head while the remaining 75µL is disposed of through the sampling needle into a dedicated washing chamber The 25µL whole blood sample is transported to the mixing chamber through the sampling needle with an addition of 4mL of diluent making a 1:160 primary dilution 25µL of the diluted sample is aspirated into the sampler head and then mixed with another 4mL of diluent which is dispensed into the RBC chamber forming a 1:25,000 overall RBC dilution The remaining mix dilution is moved to the WBC chamber where 0.9mL of lysing reagent is added. Bubbles mix the lyse and the mix dilution. This creates a dilution of 1:196, suitable for photometric measurement and WBC counting The WBC cell counting is performed, followed by an HGB measurement Then the RBC and PLT counting is performed Lastly, the system drains and cleans the measuring chambers and related tubing, and prepares for the next sample. Apertures are cleaned with high-voltage burning pulses Select Next to continue. A lysed blood sample (WBC) dilution is analyzed for HGB concentration based on its stable chromogen content. The lyse reagent causes the RBCs to release cellular hemoglobin. The hemoglobin concentration is measured by taking a photometric reading across the WBC chamber. The HGB result is calculated as the difference between a blank and a sample measurement with and without illumination to reduce the effect of liquid refraction and incident light. Select Next to continue. Determines the number and volume distributions of cells A constant current flows between the electrodes on both sides of the aperture. Each cell that passes through the aperture causes a change in the electrical impedance or resistance of the diluted blood sample. The intensity of each pulse is proportional to the volume of the particle. The volume distribution diagrams of the particles are displayed as the WBC, RBC, and PLT histograms measured in fL units. Electronic discrimination by size allows separation of PLTs, RBCs, and WBCs. Discriminators are indicated by dotted vertical lines on the histograms. The system detects this change in impedance and converts it to an electrical pulse. The number of pulses is proportional to the number of particles in the diluted sample. The system detects and measures changes in electrical impedance when particles suspended in a conductive liquid pass through a small aperture. Select Next to continue. The WBC lytic process allows the system to simultaneously count and size-differentiate the WBCs into three parts: LYM, MID, and GRA. Three elements determine where the different cell types fall in the WBC histogram: Chemical formulation and concentration of the lytic reagent Controls how different WBC types are differentially lysed. The concentration controls the rate of lysing or shrinking and the time of incubation. Type and maturation of the cells present for analysis Different WBC types and grades of maturation lyse at different rates. Lymphocytes are the most sensitive while band neutrophils and segmented neutrophils are the least sensitive. Time window in the lytic process Cells are counted and sized during this time window. Because the lytic process is a dynamic reaction, the count and sizing-time window used during the process has been optimized. Eosinophils, basophils, immature granulocytes, and blasts have cell membranes that are sensitive to the lytic process classifying them as mid-size cells, at the time these cells are counted and sized. Select Next to continue. The sampling needle aspirates 100µL of the EDTA anti-coagulated whole blood sample. 25µL of this sample is separated in the sampler head, while the remaining 75µL is disposed of. The 25µL whole blood sample is transported to the mixing chamber with the addition of 4mL of diluent making a 1:160 primary dilution. 25µL of the diluted sample is aspirated into the sampler head and mixed with another 4mL of diluent, which is then dispensed into the RBC chamber forming a 1:25,000 overall RBC dilution. The remaining mix dilution is moved to the WBC chamber where 0.9mL of lyse is added creating a 1:196 dilution suitable for photometric measurement and WBC counting. WBC counting is performed, then HGB measurement, and then RBC and PLT measurements. Select Next to continue.