hema: hematopoiesis, hemocytometer and quality control Flashcards
Deals with the study of blood, blood-forming
organs and blood diseases.
Hematology
Specialized body fluids that deliver
necessary substances such as nutrients and
oxygen to the cells and transports metabolic
waste products away from the same cells.
blood
Process of cellular formation, proliferation,
differentiation and maturation of blood cells.
Hematopoiesis
Organs and tissue areas in which blood cell
production or regulation occur
Hematopoietic tissues
areas included in fetal hematopoiesis in Hematopoietic tissues
spleen, lymphatic tissues and bone marrow
stages of hematopoiesis
mesoblastic, hepatic, & myeloid stages
the primary site/s of hematopoiesis in mesoblastic stage
blood islands of the yolk sac of the human embryo
(as early as 19th day of gestation)
Blood Cells formed in mesoblastic stage
Erythroblasts
first blood cells formed by the first month of embryonic
life
erythroblasts
Embryonic hemoglobin are formed:
- Gower I-2 zeta chains and 2 epsilon chains
- Portland- 2 zeta chains and 2 gamma chains
- Gower II- 2 alpha chains and 2 epsilon
chains
primary site/s of hematopoiesis in hepatic stage
Fetal Liver
Blood cells formed in hepatic stage
- erythrocytes still in production
- granulocytes and megakaryocytes:
3rd month of gestation - lymphocytes: 4th month of gestation
- monocytes: 5th month of gestation
what begin a limited role as
secondary lymphoid organs in mid fetal life
spleen and lymph node
fetal hemoglobin is produced during ___
4th month of gestation
also in hepatic stage
HbF- 2 alpha chains and 2 gamma chains
primary site/s of hematopoiesis in myeloid stage
bone
marrow
adult hemoglobins are produced in myeloid stage
Hb-A1-2 alpha chains and 2 beta chains & Hb-A2-2 alpha chains and 2 delta chains
becomes the only site
for RBC production, granulocytes,
monocytes, platelets and B lymphocytes at birth
bone marrow
Hematopoiesis occurs in most bones but
primarily in ____
flat bones of the sternum, ribs, vertebrae, skull and pelvis
principal source of production in adult
sternum and other flat bones
major function of bone marrow
production and proliferation of blood cells
3 Major Compartments of Cell Types of Marrow
Hematopoiesis:
stem cells, Progenitor (commited) cells, and Precursor cells-blast
Known as pluripotential or multipotential cells
stem cells
Retain the ability to differentiate into any cell
line
stem cells
Referred to as colony-forming units-spleen
(CFU-S)
stem cells
stem cells can differentiate into:
- multipotential stem cells which give rise to
non-lymphocytes - Secondary multipotential stem cells which
give rise to primitive B or T lymphocytes
known as unipotential stem cells-differentiate into only one cell line(BFU,CFU-E,CFU-MEG and
CFU-GM)
Progenitor (commited) cells
forms (myeloblast, megakaryoblasts, erythroblasts)
Precursor cells-blast
what do Precursor cells-blast form
myeloblast, megakaryoblasts, erythroblasts
Primary cells, Having capability of self renewal and can differentiate into many specialized cells.
STEM CELLS
Designed to form a particular type of cell
Committed Pluripotent Hematopoietic Stem Cell or CPHSC
CPHSC give rise to 2 groups of cells
Lymphoid Stem Cells and Colony forming Blastocytes
Lymphocytes & Natural
killer cells
Lymphoid Stem Cells
Colony forming - E
Erythrocytes
Colony forming - M
Megakaryocytes
Colony forming - GM
Neutrophils, Eosinophils,
Basophils & Monocytes
Colony Forming Unit - E
● Proerythroblast
● Early normoblast
● Intermediate normoblast
● Late normoblast
● Reticulocyte
● Matured RBC
known as Erythrocytes
Red Blood Cells
shape of mature red blood cells
biconcave disks
disk size of RBC
Has a diameter of 6-8um and a thickness of
2um
amount of RBC in male
Male: 4.50-6.80 x 10^6/uL
amount of RBC in female
Female: 3.80-4.80 x 10^6/uL
lifespan of RBC
120 days
Blood cells that FIGHTS infection.
White Blood Cells
Ref. ranges of WBC
4.0 - 11.0 x 10^3
increased in WBC
Leukocytosis
decreased in WBC
Leukopenia
2 groups of WBC
Granulocytes and Agranulocytes
Normal Marrow Composition:
● 60% - granulocytes & precursors
● 20% - erythroid precursors
● 10% - Lymphocytes, Monocytes
● 10% - Unidentified or disintegrated cells
It is a technique used to enumerate the total
cell count in the BLOOD or other Biological
body fluids. This can be done either by using
a haemocytometer manually or by electronic
cell counter automatically.
Haemocytometry
hemo means?
blood
cyto means?
cells
meter means?
measurement
hemocytometer
an instrument used to count/measure the blood cell
purpose of hemocytometer
In certain pathologic conditions the value of
different types of cells may have variation.
Thus by counting the cells in the blood or
body fluids, it can be find out if an individual
is normal or not.
purpose of cell count (generally/broadly)`
● To find out normal and abnormal count of the
cell.
● To support and confirm clinical diagnosis of
the patient.
● To find out the response of the patient to the
treatment.
who invented hemocytometer?
Louis-Charles Malassez
who modified hemocytometer?
Neubauer
an instrument used for counting the
cells in blood or fluid.
hemocytometer
Haemocytometer Box, consist of a
special thick slides, cover slips, pipette, and diluting fluids
called Neubauer’s counting chamber, diluting fluids
special thick slides
used for diluting the blood with rubber tube with
different color plastic mouthpiece for drawing
blood or fluid in pipette.
RBC and WBC pipette
parts of diluting pipettes
stem cell, bulb, rubber tube and mouth piece
has capillary bore and well grounded conical tip.
stem cell
markings of stem cell
has only two markings of 0.5 in middle of stem & 1 at the junction of stem and bulb.
contains a rolling bead that helps in mixing the blood with diluting fluid and helps in quick identification of pipette
bulb
color of bulbs
WBC - White
RBC - Red
the bulb narrows again into a short stem to which a
long narrow rubber tube (25 to 30 cm) with red mouth piece in WBC is attached. These are used to suck blood and diluents to the pipette.
rubber tube and mouth piece
bead colors of rbc and wbc pipette
rbc = red
wbc = white
marked major calibrations of rbc and wbc pipette
rbc = 0.5, 1.0 and 101
wbc = 0.5, 1.0 and 11
bulb size of rbc and wbc pipette
rbc = larger
wbc = smaller
lumen size of rbc and wbc pipette
rbc = smaller
wbc = larger
capillary bore lumen of rbc and wbc pipette
rbc = narrow
wbc = wider
speed of rbc and wbc pipette
rbc = slow
wbc = faster
mouth piece color of rbc and wbc pipette
rbc = red
wbc = white
dilution in rbc and wbc pipette
rbc = up to 100 or 200 times
wbc = up to 10 or 20 times
diluents used in rbc and wbc counting
rbc = hyaem’s fluid
wbc = turk’s fluid
dilution factor for WBC and RBC counting
WBC: FV/IV = 10/0.5 = 20
RBC: FB/IV = 100/0.5 = 200
Sum-total of all the characteristics of a
product/service that has a bearing upon the
utilization of the product product/service to the entire
satisfaction of the consumer.
Quality
4a’s in Quality
Acceptable, Accessible, Affordable and Appropriate
an activity to improve patient care by having the lab
monitor, its work to detect deficiencies &
subsequently correct them.
Total Quality Management (TQM)
to improve the patient care by placing the emphasis
on not to make mistakes in the first place.
Continuous Quality Improvement (CQI) /
Performance Improvement (PI)
external activities that ensure positive patient outcomes. It
measures what a lab can do to improve
reliability.
Quality Assurance (QA)
Principles of Quality management,
assurance, and control
● Total Quality Management of clinical
laboratory
● Control of pre-analytical variables
● Control of analytical variables
● External quality assessment & proficiency
testing programs
TQM also referred to as:
Total quality control (QC), total
quality leadership, continuous quality improvement,
quality management science or industrial quality
management.
The Universal principles of TQM are
1) Customer focus
2) Management commitment
3) Training
4) Process capability & control
5) Measure using quality-improvement tools
conformance to requirements
Quality
“Costs of conformance” + “Costs of non conformance”
Quality Costs
(WORK PROCESS) PHYSICIAN/HEALTHCARE PROVIDER
● Patient examination
● Patient testing
● Patient diagnosis
● Patient treatment
(WORK PROCESS) HEALTHCARE ADMINISTRATOR
● Processes for admission of patients
● Tracking patient services
● Discharge of Patients
● Billing for costs of service
(WORK PROCESS) LABORATORY DIRECTOR
● Processes for acquiring specimens
● Processes specimens
● Analyzing samples
● Reporting test results
(WORK PROCESS) LABORATORY ANALYST
● Acquiring samples
● Analyzing samples
● Performing quality control
● Releasing patient test results
TOTAL QUALITY MANAGEMENT FRAMEWORK
QLP, QC, QA, QI, QP
Includes analytical processess & the
general policies, prcatices, procedures that
define how all aspects of the work are done.
QLP - QUALITY LABORATORY PROCESS
emphasizes statistical control procedures, but also includes non-statistical check procedures
QC - QUALITY CONTROL
concerned primarily with broaders
measures & monitors of lab performance
(turnaround time, specimen identification,
patient identification, test utility)
QA - Quality Assessment
a structured problem solving process to
help identify the root cause of a problem & a
remedy for that problem.
QI - QUALITY IMPROVEMENT
provides the planning steps.
QP - QUALITY PLANNING
defines how quality is managed objectively with the scientific method or the PDCA cycle
FIVE Q
provides the planning step
QP
establishes standard processes
QLP
provides measures for check
QC and QA
provides a mechanism through which to act on those measures
QI
The main objective of a laboratory is to
provide reliable, timely, and accurate test results.
Quality System
QC + QA =
QUALITY ASSURANCE
Includes personnel,
instrumentation, document
control, reagent control and
corrective action.
Internal Quality Control (IQC)
External quality control is
important to ensure the
laboratory is performing to an
external standard.
External Quality Assurance (EQA)
● Audit, On-site
inspection
○ Internal
○ External
● Accreditation
MAN-DRIVEN
● Quality Assessment
○ Internal
○ External
○ Schematic
way: External quality Assessment
Scheme (EQAS)
MATERIAL-DRIVEN
refers to operational
techniques that must be included during
each assay run to verify that the
requirements for quality are met with
Quality control
refers to all those
planned and systematic activities to provide
confidence that the results given out by the
laboratory are correct
Quality assurance
ensure that the results
generated by the test are correct.
Quality Control
concerned with much more: that the
right test is carried out on the right specimen and that
the right result and right interpretation is delivered to
the right person at the right time.
Quality Assurance
purpose of quality assurance
maintenance of the overall quality of patient results
refers to the collection, transport and quality of specimen
pre-analytic
refers to the result accuracy, clerical errors, analytical errors and assay repeat rates
analytic
refers to the result reporting, record keeping for patient and QC
post-analytic
objectives of quality in lab
- support provision of high quality health-care (reduce morbidity, mortality and economic loss)
- ensure credibility of lab
- generate confidence in lab results
laboratory errors cost in
time, personal effort and patient outcomes
coordinated activities to direct and control an organization with regard to quality
Quality Management System
the path of workflow
the patient – test selection – sample collection – sample transport – report creation – report transport
Laboratory tests are influenced by
● Laboratory environment
● Knowledgeable staff
● Competent staff
● Reagents and equipment
● Quality control
● Communications
● Process management
● Occurence management
● Record keeping
errors which occur when non-analytical factors change concentration Of analytes
preanalytical variability
appropriate should be
requested & performed
test conducted
labeling of specimen
may improper; corrected by bar coding
patient identification
should be kept
minimum
TAT
entry of patient & test
details in lab registers & computers
laboratory logs
a substantial risk of
transcription error exists from manual entry
of data, even when results are double
checked; computerization reduces this error
transcription errors
essential to obtain meaningful
test result
patient preparation
container,
anticoagulant, time taken to send specimen
to lab, corrected by using vacutainer tubes &
collection of samples by lab personnel
specimen collection
critical for some tests
specimen transport
monitoring of the performance of the
centrifuge, container used for storage
specimen separation, aliquoting
variation from person to person.
Safety precautions for all specimens.
Throughout time to be monitored on the
weekly or monthly basis
personnel
must be controlled
carefully to ensure accurate measurements
by analytical methods
analytical variables
Clear concepts in relation to Analytical
methods
Calibration, trueness, accuracy,
precision, linearity, & limit of detection
Closeness of agreement b/n the
average value obtained from a large
series of results of measurements
and a true value
Trueness of measurements
The known, accepted value of a
quantifiable property
True Value
The difference b/n average value &
the true value
Bias
Result of an individual’s
measurement of a quantifiable
property
measured value
The closeness of the agreement b/n
the result of a measurement * a true
conc. of the analyte.
Accuracy
Closeness of agreement b/n
independent results of
measurements obtained under
stipulated conditions
Precision
The ability to maintain both precision and
accuracy
Reliabity
the relationship between
measured & expected values over the
analytical measurement range.
Linearity
highest measurement
result that is likely to be observed for a blank
sample.
Limit of Blank
lowest concentration of measurement that can be
consistently detected in ≥ 95% of samples
tested under routine laboratory conditions
and in a given sample matrix.
Limit of Detection
lowest actual amount of analyte that can be reliably
detected and at which the total error meets
the laboratory’s requirements for accuracy.
Limit of Quantification
