Automation Flashcards
PRINCIPLE:
____: Blood is diluted in an isotonic solution and drawn through an aperture (100 um).
- Aka
- Utilizes the _____ principle
- Changes in electrical resistance are counted as _____
- positive/negative during charge
- external electrode
- internal electrode - blood is diluted with why solution
ELECTRIC IMPEDANCE
- ELECTRIC RESISTANCE
- Coulter principle
- voltage pulses
- positive/negative during charge
- cathode
- anode - saline
PRINCIPLE:
____: A diluted blood specimen passes through a steady stream through which a beam of LASER
- Aka
- LASER stands for
- analyzes (3)
- blood sample is injected into a _____: passage of fluid by layer/sheath to avoid mixing of components
- allows cells to pass through a single file until they reach the sensing zone
- light scatter types
- bending of light towards a corner or edge
- bending of light when it passes through a different media
- when the light is returned back
- light is absorbed, hence nothing is scattered
- scatter occurs within the cells - scatter light in different directions is measured by
LIGHT SCATTERING
- OPTICAL DETECTION/ FLOW CYTOMETRY
- Light Amplification by Stimulated Emission of Radiation
- cell size, complexity, and shape
- Laminar flow
- Hydrodynamic focusing
- light scatter types
- Diffraction
- Refraction
- Reflection
- Absorption
- Internal Scattering - Photodetectors
More about Light Scattering
- ANGLE
- cell volume/ size
- internal complexity _____; aka _____ - forward scatter + right angle scatter
- does not penetrate the cells
- detects granules, lobes, or nucleus; for differential count
- ANGLE
- FORWARD ANGLE (LOW ANGLE)
- RIGHT ANGLE (HIGH ANGLE); SIDE SCATTER - Differential Scatter
- Direct current
- Radiofrequency
HOW DOES MACHINE DILUTE THE BLOOD SAMPLE
- wbc dilution
- rbc dilution
HOW DOES MACHINE ANALYZE THE READING AND DISPLAY RESULTS IN NUMERICS
1. line graph
2. dot graph
HOW DOES MACHINE DILUTE THE BLOOD SAMPLE
- 1:500
- 1:50,000
HOW DOES MACHINE ANALYZE THE READING AND DISPLAY RESULTS IN NUMERICS
1. HISTOGRAM
2. CYTOGRAM
______: graphic representation of cell size versus cell frequency
- x/y axis?
- cell size
- cell frequency - RBC HISTOGRAM
- threshold
- where ___ & ___ are derived
- shape:
- wide width:
- shift to left: disease
- shift to right: disease - one possible error: presence of
HISTOGRAM
- x/y axis?
- x axis (abscissa)
- y axis (ordinate) - RBC HISTOGRAM
- 36 – 360 fL
- MCV and RDW
- Gaussian shape
- ANISOCYTOSIS
- MICROCYTOSIS: iron deficiency anemia
- MACROCYTOSIS: megaloblastic anemia - Large Platelets
HISTOGRAM cont
PLATELET HISTOGRAM
1. threshold
2. where ____ (threshold) & ____ are derived
3. one possible error: presence of
WBC HISTOGRAM
1. lymphocyte threshold
2. Mononuclears (mid cells)threshold
- 3 wbc under this
3. Granulocytes threshold
PLATELET HISTOGRAM
1. 2-20fL
2. MPV (6.8-10.2fL) & PDW
3. MICROCYTIC CELLA
WBC HISTOGRAM
1. 35 - 90 fL
2. 90 - 160 fL
- BASO, EOSINOPHIL, MONOCYTES
3. 160 - 450 fL
______: visual display of 2-cell characteristics such
as internal cell complexity and relative size
- aka
- used in 5-part automated differential: utilizes ______ (conductivity), _____ (impedance), & _______ (added to separate the 5 wbcs)
- x/y axis.?
- cell size
- internal cell characteristic - cytochemical stains
- for neutrophil & eosinophils
- for basophil
- for monocytes
CYTOGRAM
- SCATTERGRAM
- RADIOFREQUENCY, DIRECT CURRENT, LIGHT SCATTERING
- x/y axis.?
- y axis
- x axis - cytochemical stains
- Peroxidase
- Alcian blue/Toluidine blue
- Lipase/ Non Specific Esterase
CYTOGRAM cont
- for special cell population (e. g. nucleated RBCs)
—- - 3-parameter differential wbc
- 5-parameter differential WBC
- Fluorescent dyes
—- - HISTOGRAM
- CYTOGRAM
OTHER PARAMETERS
Hemoglobin
1. uses the ______
2. wavelength used
Hematocrit
1. uses the ___ method
2. formula which is derived from (HCT/MCV) x 1000
3. ____ may also be used
- increase red cells = ___ resistance = ____ conductivity
- __ pcv = __ conductivity
- __ pcv = __ resistance
INDICES
1. from histogram
2. calculated from measured and derived values
Hemoglobin
1. cyanmethemoglobin principle
2. 525nm
Hematocrit
1. indirect method
2. ((MCVxRBC count)) /10)
3. Conductivity
- increase red cells = more resistance = less conductivity
- high pcv = less conductivity
- high pcv = high resistance
INDICES
1. MCV and RDW
2. MCH and MCHC
SOURCES OF ERRORS
Positive:
1. when plasma protein thickens or crystallizes
2. improperly grounded or
shielded equipment
3. vigorous mixing; gentle inversions only
4. causes dust = increase cell count
5. agglutinated ___ or ___
Negative:
1. excessive lysing of ___
2. Improper setting of ____ or ____
3. agglutination of ___ (3)
Positive:
1. Aperture plugs
2. Extraneous electrical pulses
3. Bubbles in the sample
4. Improper setting of aperture current or threshold
5. Red Cells or Platelets
Negative:
1. RBCs
2. aperture current or threshold
3. rbc, wbc, platelets
Internal Quality Control for Hematology Analyzers:
- quality control check in which the averages of the
MCV, MCH, and MCHC are tracked for batches of 20
patients
- aka - patients test results are compared to hismprevious results; results are easily retrieved as they are stored by the machine
- suggest cells types/abnormalities; indicate investigation before final reporting
- X Bar B
- moving average - Delta Checks
- Flags
Basic Components Common to Most Hema Analyzers:
- inc. aspirating unit, dispensers, dilutors, mixing
chambers, aperture baths, and/or flow cells, & hemoglobinometer - vacuum and pressures for operating values and
moving the sample through the system - electronic analyzers and computing circuitry for processing data
- Hydraulics
- Pneumatics
- Electrical systems
