Transcript Document

Expectations Vs Achievements Quality Control Of Blood
Components
Sitalakshmi S
Professor and Head
Department of Clinical Pathology
St John’s Medical College, Bangalore
THE CASE…….
• A 65-year old lady, was referred to the Medical
College Hospital for recent onset fatigue and
weight loss .
• A CBC showed a WBC count 55,000/ul with 90 %
peroxidase positive blasts, normochromic
normocytic anemia (Hgb 8 g/dl) and
thrombocytopenia (40,000/ul).
• On physical exam, the patient was afebrile,
normotensive
• There were no bleeding manifestations
• An admission ECG and history are negative for
cardiovascular disease
NEED FOR TRANSFUSION?
• Does the patient require transfusion of:
packed red blood cells?
platelets?
• Although the patient is mildly anemic and
thrombocytopenic, she does not fulfill criteria for
transfusion at this time.
• Her Hgb > 7g/dl with no history of cardiovascular
disease or symptomatic anemia (other than
fatigue).
• If the patient had a history of cardiovascular
illness or signs or symptoms of significant anemia,
it would be appropriate to maintain her Hct at a
higher baseline.
• Similarly, the patients platelet count (40,000/ul )
with no bleeding manifestations does not require
prophylactic platelet transfusion
FURTHER CLINICAL COURSE….
• Eight days after admission for induction
chemotherapy, the patient's CBC shows:
WBC 500/ul Hgb 6.9g/dl Platelet 8,000/ul
The patient's physician ordered 2 units
leukoreduced and irradiated packed red blood
cells and 6 units of pooled platelet concentrates
(3 X 10¹¹ platelets total).
Was transfusion of PRBC and platelets
appropriate in this patient at this time?
NEED FOR TRANSFUSION…..
• Yes. The patient's hemoglobin < 7.0 g/dL in the
setting of a bone marrow failure
• Likewise, the patient's platelet count has now
decreased to the point where she is at risk for
spontaneous hemorrhage
• A CBC 1 hour after the administration of platelets and
PRBC shows:
Hgb 9.1g/dl Hct 27.3 % Platelets 30,000/ul
• Corrected count increment (CCI)
(postTPC - preTPC) x (BSA in M²)/(TNPTx 10¹¹) where:
• TPC=transfusion platelet count
• BSA=body surface area
• TNPT=total number of platelets transfused
For this patient: post TPC 30,000 pre TPC 8,000
CCI=(30-8) x 1.5/3 = 11
• Did the patient get an appropriate response from the
PRBC and platelet transfusions?
• Yes to both. The patient was transfused with 2 units of
packed red cells (PRBC), Hgb of 6.9g/dl rising to 9.1g/dl.
An average adult show a 1 g or 3% rise in Hct with each
unit of packed red cells.
• Likewise, the calculated CCI was 11.0. A CCI of > 7.0 is
considered a good clinical response.
What are the factors that affect
the patient’s response to
transfusion of blood components?
• Quality of blood components transfused
• Patient’s disease condition and patients
physiological response to transfusion
• How do we as transfusion specialists ensure
quality of blood components?
• What is our role in patient transfusion therapy?
• Quality programmes and systems in transfusion
medicine differ slightly from other disciplines of
laboratory medicine
• It takes two different forms.
• the blood supply system and
• Clinical transfusion therapy.
• The approach used to ensure highest quality in
the blood supply system is similar to that used in
the manufacture of pharmaceuticals
• The approach used to ensure that the patient
receives highest quality of transfusion therapy is
a part of hospital’s overall quality care program
• The measures taken for quality assurance in
transfusion medicine are:
• Measures needed during the process of blood
component preparation and storage
• Measures taken during the process of actual
transfusion of the blood components. This aspect
has more to do with good clinical transfusion
practices
STANDARDS FOR QUALITY
MONITORING
• The wide variability of the source material
from which blood components are
prepared makes it difficult to set stringent
limits.
• Nevertheless, realistic minimum
specifications should be set and complied
with.
STANDARDS FOR QUALITY
MONITORING

The standards are based on minimum
requirements
•
On what is achievable using the most up-to-date
methods and systems
• Testing of random components to ensure they
achieve reliably minimum specific requirements
as per the standards
COMPONENT PREPARATION
• The quality of the components is assured by
control of all stages of manufacture
• donor selection
• Blood collection
• Component separation
• labeling
• Storage
• The starting materials for preparation of blood
components are blood donations collected from
suitable donors.
• Conditions of storage or transport
• and the time prior to processing,
• are contributing factors to the quality of the
product.
• Delays in preparation
• unsuitable conditions of storage or transport
• may adversely affect the quality of the final product.
• Blood and blood components should be placed in
controlled and validated conditions as soon as possible
after collection.
Quality assurance is concerned with every aspect of
transfusion practice and applied to all activities of
blood transfusion service from:
Identification of suitable
Blood donors
Blood transfusion
QUALITY
ASSURANCE
Collection of blood
Preparation of blood
components
SRANDARD OPERATING
PROCEDURES
• The standard operating procedures should
describe the specifications for materials that will
influence the quality of the final blood
component.
• Specifications should be in place for blood
components (intermediate and final
components), starting materials, additive
solutions, blood collection bags and equipment.
BLOOD COLLECTION
• The collection process itself is crucial for the
quality of blood components.
• Measures such as a reliable arm-cleaning and
disinfection procedure, the use of closed and
sterile collection systems should be
implemented.
• Free flow of blood during collection is crucial
• Time limits is defined for the processing of blood
components.
• Each component should be visually inspected at
each stage of processing and immediately prior to
issue.
• The component must be withdrawn if there is
evidence of leakage, damage to or fault in the
container, excessive air, suspicion of microbial
contamination or any other contraindications
such as platelet clumping, unusual turbidity,
haemolysis or other abnormal colour change.
Frequency of quality control
•
Should be performed on
• at least 1% of all components produced
• for all parameters to be measured
•
If fewer than 100, then at least 4 per month
•
75% or more of components monitored must meet
the specifications
TRANSPORT
• Donations and samples should be transported to the
processing site in accordance with procedures that ensure
a constant approved temperature.
• This is especially important when blood is transported
from distant collection sites.
• Portable temperature loggers may be used to record the
temperature during the transportation of blood to the
processing site.
COMPONENT WEIGHT: VOLUME
• To provide information, which is useful for
clinicians, the component specifications generally
require the component label to indicate a
volume.
• whole blood volume is calculated by deducting
the weight of the bag assembly and dividing the
resulting weight by the specific gravity of 1.06
COMPONENT WEIGHT: VOLUME
• For red cell components, volume is calculated by
weighing the pack, deducting the weight of the
pack assembly only and dividing the resultant
weight by the specific gravity 1.09
• For platelets and plasma components, volume is
calculated by weighing the pack, deducting the
weight of the pack assembly and dividing the
resulting weight by the specific gravity of 1.03.
STANDARD OPERATING PROCEDURES
• The standard operating procedures for
component preparation should be followed at all
times using the validated methods.
• Any deviations from these established procedures
and processes may result in products not meeting
specifications and such products should be
considered as non-conforming products and must
not be released .
METHODS OF PRODUCTION
• Blood components may be prepared by using a
centrifugation step with subsequent separation, or by
apheresis technology during collection
• The use of closed systems is a must for all steps in
component processing.
• Where sterile connecting devices are used to maintain a
functionally closed system they should be correctly used
in accordance with a validated procedure. The resulting
weld should be checked for satisfactory alignment and
integrity.
EQUIPMENT
• Equipment used in collection, processing, testing and
storage of blood and blood component should be
observed, standardized and calibrated on a regularly
scheduled basis
• Procedures should be described in the Standard
Operating Procedure (SOP) Manual
EQUIPMENT PERFORMANCE MONITORING
Equipment
Performance
Frequency
Frequency of Calibration
Blood mixer
Observe wt. of first container Each day of use
of blood filled for correct
results
Standardize with
container of known
mass or volume before
initial use and after
repairs
Blood bag
weighing scale
Standardize against
container of known weight
Each day of use
As often as necessary
Refrigerated
centrifuge
Observe speed &
temperature
Each day of use
As often as necessary
Temperature
recorder
Compare against
thermometer
Daily
As often as necessary
Water bath
Observe temp.
Each day of use
As often as necessary
REFRIGERATED CENTRIFUGE
• Calibrated upon installation and repair
• Calibration of speed with tachometer twice a year
• Timer to be checked with tachometer
PLATELET AGITATOR
• Number of strokes 70+/- 10 per min
• Periodic cleaning and lubrication
Quality Control of equipment for
component storage
• Daily periodic temperature monitoring of
refrigerators, freezers and platelet incubator
• Temperature check at different locations in large
equipment
• Audio and visual alarms to alert
• Continuous temperature recorder
• Actual temperature checked with
Hg themometer in glycerol
CENTRIFUGATION
• The centrifugation parameters (revolutions per minute,
temperature, time, acceleration, deceleration) are
important for the composition and characteristics of the
specific components.
• These critical parameters should be defined on the basis
of validation data that demonstrate a process that
consistently produces quality products.
• For each run, the centrifugation records should identify
the operator and confirm that the centrifugation process
was performed according to specifications.
SEPARATION
• After centrifugation, the bag system should be carefully
removed from the centrifuge and placed into a plasma
expressor or blood separation system.
• The different layers of the components (red cells,
platelets, plasma) should be transferred to the satellite
bags within the closed systems, in a manner designed to
optimize the harvest of the intended component while
minimizing the carry-over of other component fractions.
• Alternatively, blood components can be separated during
collection by apheresis technology
PACKED RED CELL CONCENTRATE
• Red-cell concentrates are obtained from whole blood by
centrifugation and removal of plasma with or without
buffy coat, depending on the centrifugation parameters.
• The red cells should be stored at 2–6°C as soon as
possible. Alternatively, red-cell concentrates may be
obtained using an apheresis system and stored at 2–6°C.
LEUCOREDUCTION
• To obtain leukocyte-reduced red-cell concentrates, either
whole blood filtration can be applied prior to separation
or there can be a post-separation filtration of the red-cell
concentrate..
• Red-cell concentrates are stored at 2 -8oC. The storage
time depends on the anticoagulant/preservative solution
used.
• The introduction of any leukocyte reduction process
either by filtration or special centrifugation technique
requires careful validation
LEUCOREDUCTION
• Counting residual WBC by automated cell
counters may not be reliable for very low WBC
count of < 100WBC /ul
• Nageotte counting chambers are reliable for as
low as 1 WBC/ul
• Flow cytometer can detect as low as 0.1 WBC/ul
QC OF RED CELL CONCENTRATE
PARAMETER
QUALITY REQUIRMENTS
Frequency of testing
VOLUME
280+/-60 ML
1% of all units
HEMATOCRIT
0.70+/-0.05[ >70%]
1% of all units
Sterility
Culture
1% of all units
• Further methods of preparation, such as irradiation or
washing, are applied to obtain specific red-cell products,
depending on the clinical indication.
• Periodic quality control should be performed on the final
product to ensure that the manufacturing process is consistent
At a minimum, the following critical parameters should be
checked during the quality control assays:
— volume
— haematocrit
— haemolysis at the end of storage
— residual leukocytes, if leukocyte reduction is performed.
FRESH FROZEN PLASMA
FREEZING OF PLASMA
• Freezing is an important processing step that has an
impact on quality of plasma. The rate at which freezing
proceeds and the core temperature are both important
parameters.
• Freezing speed will be influenced by the the freezing
equipment, loading pattern and the volume of plasma.
• Rapid plasma freezing prevents or reduces the loss of
critical constituents such as Factor VIII in frozen plasma.
FRESH FROZEN PLASMA
• FFO is prepared either from whole blood or from plasma
collected by apheresis, and is frozen within a defined
period of time to a temperature that should adequately
maintain the labile coagulation factors in a functional
state.
•
Factor VIII content is critical both as a quality indicator
and to assure the efficacy of cryoprecipitate.
• If plasma is separated from a unit of whole blood that is
refrigerated to 4°C, centrifugation should preferably take
place within eight hours of collection
QC OF FFP
PARAMETER
QUALITY
REQUIRMENTS
Frequency of testing
VOLUME
200-250 ML
4 units per month or 1%
STABLE COAGULATION
FACTORS
200 UNITS
4 units per month or 1%
FACTORVIII
0.7 UNITS/ML
4 units per month or 1%
FIBRINOGEN
200-400 mg
4 units per month or 1%
PLATELET CONCENTRATE
PLATELET CONCENTRATES
• Platelet concentrates are derived from whole blood or are
obtained by apheresis.
• After collection, whole blood can be kept at 20°C and
24°C,. for up to 4 – 6 hours
• The whole blood unit is centrifuged so that an optimal
number of platelets remain in plasma (platelet-rich
plasma, or PRP). Platelet concentrates are then obtained
by hard-spin centrifugation of PRP and are then
resuspended.
PLATELET CONCENTRATES
•
if whole blood is centrifuged so that the blood platelets
are primarily sedimented to the buffy coat layer, the buffy
coat is separated and further processed to obtain a
platelet concentrate.
• Either a single buffy coat or a pool of buffy coats is
diluted with plasma, and platelets are concentrated by
further centrifugation.
• The platelet content per unit depends on the method of
preparation. Similarly, the residual leukocyte content will
vary according to the centrifugation parameters
• Platelet concentrates (both from whole blood and
apheresis) should be stored in conditions that guarantee
that viability and haemostatic activities are optimally
preserved.
• The storage temperature should be 20–24°C.
• Continuous gentle agitation of platelets during storage
should be sufficient to guarantee the availability of
oxygen to the platelets (but should be as gentle as
possible).
• A storage time should not exceed five days
QC OF PLATELET CONCENTRATE
(PREPARED FROM BUFFY COAT)
Parameter
Quality requirement
Frequency of control
70-90 ml
4 units / month
> 6-9 x 1010
4 units / month
> 6.0
4 units / month
RBC contamination
Traces to 0.5 ml
4 units / month
WBC contamination
< 5.5 x 106
4 units / month
Volume
Platelet count
pH
QC OF PLATELET CONCENTRATE BY PRP
PARAMETER
QUALITY
REQUIRMENTS
Frequency of testing
VOLUME
50-70ML
All units
PLATELET COUNT
>3X10 10 / UNIT
4 units per month or 1% if
> 100
PH
>6
4 units per month or 1% if
> 100
RBC CONTAMINATION
<0.1X10 12/L
4 units per month or 1% if
> 100
WBC CONTAMINATION
<1.5X10 9/L
4 units per month or 1% if
> 100
QC OF PLATELET CONCENTRATE BY
APHERESIS
PARAMETERS
QUALITY REQUIRMENTS
VOLUME
200-500 ml
PLATELET COUNT
>3.0X10
PH
>6
LEUCOCYTES
< 0.03X10 9/L
RED CELLS
TO 0.5ML
11/unit
CALCULATION THE PLATELET
COUNT PER BAG
• Weight of empty bag=24gm
• Volume =weight of plt bag—wt of empty bag
1.03
Eg:Wt OF PLT BAG=89
VOLUME=89-24=65gm,TO CONVERT TO mL
65 =63ml
1.03
• VOLUME=63ml
• PLT COUNT=NO.OF PLT/ulX1000XVOLUME
• PLT COUNT=10X1000X63
•
==6.3 X1010/L
CRYOPRECIPITATE
• Cryoprecipitate is the cryoglobulin fraction of
plasma and contains a major portion of the Factor
VIII, von Willebrand factor, fi brinogen, Factor XIII
and fibronectin present in plasma.
CRYOPRECIPITATE
• Plasma is allowed to thaw either overnight at
2–6°C or by a rapid-thaw technique.
• Following thawing, the supernatant cryopoor plasma and the cryoprecipitate are
separated by hard-spin centrifugation. The
cryo-poor plasma is then expressed into a
transfer bag. The two components are
refrozen to the appropriate core
temperature.
QC OF CRYOPRECIPITATE
PARAMETER
QUALITY REQUIRMENTS
VOLUME
200-250 ML PLASMA
STABLE COAGULATION FACTORS
200 UNITS
FACTORVIII
0.7 UNITS/ML
FIBRINOGEN
150-250 mg
QC OF CRYOPRECIPITATE
• FOR FACTOR VIII assay -TAKE 1/10 DILUTION
• [0.9ml IMIDAZOLE& 0.1ml CRYO]
• % ACTIVITYX DILUTION FACTORX VOLUME OF CRYO
• Eg:96X10X12mL = 111.20IU/BAG
•
100
• Ensuring quality of the prepared blood
components is the first step towards achieving
optimum benefit to the patients
• Ensuring good clinical transfusion practices is of
utmost importance for optimum benefit to
patients
CLINICAL TRANSFUSION PROCESS
• The Transfusion of the right blood component to
the right patient at the right time, in the right
condition and according to appropriate
guidelines
• A chain of integrated events that begins with a
correct decision that the patient needs blood and
ends with an assessment of the clinical outcome
of the transfusion.
• Its goal is to achieve optimal use of blood
OPTIMAL USE OF BLOOD
• The safe, clinically effective and efficient use of donated
human blood
• Safe: No adverse reactions or infections
• Clinically effective: Benefits the patient
• Efficient: No unnecessary transfusions
• Transfusion at the time the patient needs it
• AABB seeks to promote an interdisciplinary dialog
that recognizes the critical importance of blood
transfusion while also encouraging an approach to
patient care that is designed to reduce the
occurrence of preventable transfusions.
• Such an approach requires the involvement of
clinicians, laboratory personnel, nursing staff,
surgeons, anesthesiologists, and administrators.
QUALITY TRANSFUSION SERVICES
• Clinical transfusion guidelines
• audit systems to monitor adherence to the guidelines
• the hemovigilance program which monitors the entire
blood supply value chain,
• Each of these systems has a different focus:
• the aim of clinical transfusion guidelines is to give
direction to the clinician on when to transfuse and what
the expected outcome should be.
• Guidelines are therefore a tool to ensure appropriate
utilization of blood products.
• This is of critical importance in light of possible
transfusion complications and a dwindling donor base.
• Each patient must be evaluated individually and,
if justified, the clinician can adjust the treatment
guidelines for a specific patient.
• The decision to transfuse is therefore based
ultimately on a clinical assessment of a specific
patient’s condition and appropriate laboratory
parameters.
• Transfusion therapy must always be of overall
benefit to the patient.
• In the field of transfusion practice, controversies
exist in the following areas • When to transfuse?
• What to transfuse?
• How much to transfuse?
QUESTIONS TO BE ANSWERED IN THE
DECISION MAKING PROCESS
• What improvement in the patient’s clinical condition am I
aiming to achieve?
• Can I minimize blood loss to reduce this patient’s need for
transfusion?
• What are the specific clinical or laboratory indications for
transfusion for this patient?
• What is the time frame of decision making
urgent/elective?
• What are the risks of acquiring HIV/ hepatitis, through the
blood products that are available for this patient?
• Do the benefits of transfusion outweigh the risks for this
particular patient? How should the component be
administered, monitored and its efficacy documented?
• Is the component easily available?
• What other options are there if no blood is available in
time?
• Will a trained person monitor this patient and respond
immediately if any acute transfusion reactions occur?
• Have I recorded my decision and reasons for transfusion on
the patient’s chart and the blood request form?
• Is the patient/relative fully informed and consenting to
medical decisions?
• The primary goal of modern blood transfusion therapy is
to ensure that the patients receive safe, reliable and
effective transfusion of the required blood components
where the benefits outweigh the risks.
• The transfusion medicine specialists plays an important
role in guiding the clinicians regarding good transfusion
practices and also ensure preparation of blood
components as per specifications of standards
THANK YOU