Automated Hematology, Manual Cell Counts, and Slide Preparation
When preparing slides, ______________ inside EDTA or Microcontainers should be used
whole blood
_________ whole blood should be made into a slide within 2-3 hours of collection
EDTA
_________ whole blood should be made into a slide within 1 hour of collection
Microcontainer
The ________________ method is the most common spreading method for creating slides
Push-Wedge
A microhematocrit tube (preferably _______________ device) is used to place the blood drop onto the slide
DIFF-SAFE
The spreader slide is held at a ______ degree angle
30-45
A _____ objective is used for the initial scan
10x
During the initial scan you should look for proper ___________ and slide preperation/ quality
staining
During a manual cell count you check RBC and WBC morphology, as well as perform a 100 WBC count differential, and a ___________ and WBC estimate
Platelet
When performing a differential count, you start with an initial scan and locate the thin area, you then switch to 100x and count __________ and __________
cells and platelets
For a RBC ____________ check, scan 10 fields of 200-250 RBCs
morphology
RBC morphology is reported as either ______, ______, or ______
N/N, Micro/Hypo, or Macro/N
With a _____________________, 100 WBCs are counted and each type is recorded
WBC differential
If ⪰6 nRBCs are present every 100 WBCs, a correction is required using the formula _____________________
#WBC x 100/ 100 + #nRBCs
Count the platelets in 10 fields and divide the sum by 10 to get the average, which can be multiplied by ___________ to get the wedge preparations
20,000
__________ estimates are done under 100x with ~ 200 RBCs in the same field
Platelet
__ or less platelets are considered decreased
7
_____ platelets is considered adequate
8-20
___+ platelets is considered increased
21
_________________ are preformed during the differential and is done using a 40x objective
WBC estimates
Formula for the average of 10 fields is total #WBCs/ 10, further multiply average by ________ to determine the WBC estimate
2,000
A Three-Part instrument measures ___________, lymphoocytes, and monocytes
granulocytes
A Five-Part instrument measures __________,____________.____________, lymphocytes, and monocytes
Neutrophils, Basophils, and Eosinophils
________________________ have improved accuracy and precision because many more cells are counted
Hematology analyzers
The principals of operation of hematology analyzers is __________________________________(6)
Electrical Impendence, Radio Frequency, Optical Scatter, VCS Technology, Hydrodynamic focusing, and flow cytometry
______________________ is where cells are pulled through an aperture in a glass tube (creating a vacuum), cells pass through this aperture causing a voltage change which generates a measurable pulse
Electrical impendance
The number of pulses with electrical impendance is the number of cells and the pulse size is the __________ of the cell
volume
Radio Frequency resistance detects cell size based on ________________
cellular density
In Radio Frequency, ____________________ is directly proportional to pulse size or a change in RF resistance
nuclear volume
With ________________, cells pass through a flow cell with a laser focused on it. The scattered light is converted to electrical pulses using photodetectors
optical scatter
A _____________ graphically measures size vs frequency of blood cells
Histogram
Types of Histograms are _______, _______, and _______, Histograms
RBC, WBC, and Platelet
Samples for automated cell counting is limited due to ________, _________, and _________
Cold Agglutinins, Lipemia, and icterus
QM Reference values are determined by ___________
population
At least __ samples establish average values and ranges
20
____________ are materials or devices with known quantitative/qualitative characteristics
Calibrators
___________ verify that the instrument is running properly
Controls
A ________ is a sudden change
shift
A _______ is a continuous change
Trend
__________________________ is a precision measurement of distance to mean
Standard Deviation
_____________ ensures accuracy and should be done every 6 months or of doubt of accurate results
Calibration
____________ verifies accuracy and precision
Quality control
Daily controls should be run every 8 hours and must be ∓__SD
2
Pre-analytical factors include _________________________ (4)
Labeling, sample quality, collection time, and mixing
Post-Analytical factors include ______________________________ (5)
Flags, reflex testing, delta checks, critical values, and multivariate checks (rule of three)
Hct, MCV, MCH, MCHC, RDW, and MPV are all ____________ by hematolgy analyzers
calculated
Diluted Samples are stable for __ hours before WBCs begin to lyse
3
The _______________ consists of a reservoir, capillary pipette, and a pipette shield
Leukochek
The Leukochek and Unopette are common ______________________
dilution systems
The Reservoir contains 1.98ml of ________________, which causes RBCs to lyse; dilution factor is 1:100
Ammonium oxalate
After adding dilutent to sample, it has to settle for __ minutes
10
Charged Neubauer Hemacytometers have to sit in a humidity chamber for __ minutes after creation
15
With a NH, WBCs are counted on the 9 large squares on the __ objective
10x
Platelets are counted with a __ objective on the center square of a NH
40x
WBC QC counts must be within __ of each other
20%
The Depth factor of both WBC and Plt QC is __ (due to 0.1mm depth)
10
The Dilution Factor of both WBC and Plt QC is __ (due to 1:100 DR)
100
Plt QC counts must be within __ of each other
10%
The WBC count formula is:
cells/mm³ = (Avg# cells x 10 x 100)/9
The Plt count formula is:
Plts/mm³ = (Avg# Plts x 10 x 100)/1