Random
How are retics counted on the three analyzers?
Coulter: Supravital staining; impedance volume and conductivity and light scatter measurement (VCS)
Sysmex: Fluorescent Staining; forward light scatter and side fluorescent light detection
Cell-Dyn: Fluorescent Staining; low-angle scatter, and fluorescent light detection
Flow cytometers used for analysis of WBCs, plts, or RBCs
hydrodynamically focused sample stream directed through a quartz flow cell past a laser
Optical Scatter
What is the calculation for absolute WBC counts?
WBC*(.__)(from mannual diff)
What do you do with a hemolyzed specimen?
Redraw
What is the calculation for MCV?
(HCT*RBC)/10
What analyzer(s) used SLS (Sodium Lauryl Sulfate) to measure HGB?
Sysmex
What are the four reasons your MCHC > 37?
Instrument error (look at Hgb or Hct)
Spherocytes
Lipemic specimen
Cold agglutinin
What is the hematocrit calculation?
(RBC*MCV)/10
High voltage electromagnetic current flowing between apertures simultaneously
Volume of cell =change in direct current
Pulse size is proportional to cell density (nuclear volume)(complexity of cell)
Radiofrequency
If there is RBC agglutination what is it caused by and what do you do to fix it?
Cold agglutin heat it to 37 degrees Celsius and rerun it
In optical scatter
Forward Scatter=
Side scatter =
Forward: size
Side: complexity
Uses electrical impedance to count cells
-changes in electrical resistance as cell move through an aperture, current impeded as cells pass over the sensor
# of pulses=# of cells, Height of pulses=MCV
Coulter principle
What do you do with a lipemic sample? What test result does it affect?
Ultracentrifuge, Hgb because it's measured on a spectrophotometer
What is the equation for corrected retic?
Retic%*(Patient HCT%/45)
What analyzer uses MAPSS? What does it stand for?
Cell-dyn
Multi-angle-polarized-scatter-seperation
What is an example of a poor delta check?
WBC count
What are some good delta checks?
HGB, MCV, Plt, HCT
What is the calculation for MCHC?
(HGB*100)/HCT
What analyzer uses VCS? What does it stand for?
What are the two chamber in the Coulter and what technology do they use in each chamber?
RBC chamber: electrical impedance to count RBCs and Plts
WBC Chamber: impedance for WBC count, drain into hemoglobinometer (cyanmeth)
uses VCS (Volume Conductivity and Scatter) with hydrodynamic focusing for WBC diff
What is the equation for MCH?
(HGB*10)/RBC
What are the three channels in the cell dyn and what does each channel use for its measurements?
Optical Channel: Impedance and MAPSS for count and diff for WBCs
Impedance Channel: impedance to count RBCs and Plts (uses coincidental correction instead of hydrodynamic focusing)
Hgb Channel: uses cyanmethemoglobin
Which analyzer(s) calculate HCT?
Coulter and Cell-Dyn
What are the three channels of the Sysmex and what does each channel use?
WBC Channel: electrical impedance with floating thresholds to count WBCs, Diff chamber using flow cytometry and RF/DC to get Diff
RBC/Plt Chamber: Electrical impedance with floating thresholds HCT measured
HGB chamber: Spectrophotometry uses SLS(Sodium Lauryl Sulfate)
Which analyzer(s) use modified cyanmethemoglobin to measure HGB?
Cell-dyn and coulter