QUALITY ASSURANCE
Sample Integrity
Lecture 2
• A test result is no better than the quality of the specimen
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received in the laboratory
A poor quality specimen will probably produce an
inaccurate and potentially dangerous result
Blood and other body fluids removed from the body start
to change immediately
Precautions must be taken to minimize these changes
and to ensure that the test result will accurately reflect the
physiologic and pathologic state of the patient
Lab. is responsible for the test result and therefore is
obliged to take precautions so that a good-quality sample
is received
• When all of the following criteria are fulfilled, the
sample received in the lab. will be of good
diagnostic value
• Specimen collection procedure is clearly defined
• When concisely designed requisition and report forms
are used
• Proper method of collection, transportation, processing
and storage are provided
Specimen Collection Manual
• The Specimen Collection Manual is important in that it
provides written instructions for the proper and adequate
collection of specimens capable of giving timely and
medically important data
• Many times the collection of specimens may be beyond
the laboratory's control as nurses, medical students, and
physicians will be responsible for the acquisition of the
specimen
• A complete and up-to-date collection procedure manual,
covering every test that the laboratory offers, should be
distributed to all collection and nurses stations
Specimen Collection Manual
• Laboratory personnel are responsible for
• for training other personnel involved in specimen
collection and transport and for communicating
effectively in order to maintain optimal quality of
specimens for laboratory testing
• minimizing preanalytical errors based on acceptance or
rejection of the received specimens
• Since preanalytical errors seem to make up the
majority of most laboratory test problems, proper
training is an important area to address
The Specimen Collection Manual (in brief)
1. Test name with alternate names and commonly used
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abbreviations
Patient preparation
Nature of specimen
Specimen timing for collection
Preservative or anticoagulant
Special handling between collection time and delivery to
the laboratory
Labeling requirements
Required requisition
Criteria for unacceptable specimens
Performing laboratory's phone number and hours of
operation
Specimen Collection Manual Contents
• The manual should contain the following information for
each test
1- Test Name:
• The name of each test with alternate names and commonly used
abbreviations are listed in alphabetical or some other logical order
• Some tests are referred to by more than one name or by their
initials
• An example would be SGPT, GPT, serum glutamic pyruvic
transaminase, ALT, or alanine aminotransferase—all referring to the
same enzyme
2- Patient preparation:
• How the patient should be prepared prior to collection of the
sample should be detailed here
• For example, should the patient be fasting or two hours prandial; be
sitting or recumbent
Specimen Collection Manual Contents
3- Nature of specimen:
• The type of material to be collected should be clearly
indicated
• Blood, urine, some other body fluid, or tissue sample should be
clearly stated as the preferred specimen
4- Special timing for collection:
• Should the sample be a random one or timed to
coincide with the administration of a drug or with some
pathologic event?
• This is especially important when looking for specific
responses to treatment
• such as a glucose tolerance test, antibiotic, anti-convulsant, or
antiarrhythmic drugs
Specimen Collection Manual Contents
5- Preservative or anticoagulant:
• To maintain the specimen in an acceptable state, it may be
necessary to use an anticoagulant, preservative, or even to store
the specimen on melting ice or ice water
6- Transportation requirements:
• Special handling between the collection time and delivery to the
laboratory may be required.
• Chemicals can be altered, microorganisms die, and the specimen
altered if improperly handled during transportation.
• Transportation considerations include:
• Time
• Temperature
• Exposure to light
• Excessive vibration and rough handling
Specimen Collection Manual Contents
7 Labeling procedures:
• Specific requirements for labeling the sample should he clearly
defined
• A minimum of patient name, identification number, collector's
initials, and the date and time of collection should be labeled on the
sample
• Some specimens will require more information:
• Microbiological specimens need to have site of the sample included
• A blood sample collected for crossmatching needs to be exactly and
correctly labeled for acceptance
Specimen Collection Manual Contents
8- Required requisition:
Specific requisitions with test names and reference ranges will help
in processing the result
9- Criteria for unacceptable specimens:
• A description of unacceptable specimens may prevent the improper
collection
10- Performing laboratory:
• Each test should be listed with the phone number and hours of
operation of the performing laboratory
• If the physicians and nursing staff who will collect the samples
know where the samples should go and the hours of operation of
the performing laboratory, then improperly timed specimens may
be avoided
Sample Rejection
• A specimen should be rejected for any of the
following reasons:
a- Inadequate or improper labeling:
• Sample tubes or collection containers with no label or the wrong
name should not be accepted
b- Inadequate sample volume for amount of additive
used:
• If less than the required volume of blood is collected, there will be
an excessive amount of additive that may affect the accuracy of the
test result.
• For example, too much liquid anticoagulant relative to the blood volume
will result in a dilution error for prothrombin time in any sample collected
in a citrated tube
Sample Rejection
c- Improper collection tube or container:
• Certain tests require specific anticoagulants or preservatives to
maintain the integrity of the specimen
• The wrong additive can have a detrimental effect on the specimen,
resulting in an inaccurate result
d- Improper transportation:
• Specimens received in the laboratory that have been improperly
transported should be rejected.
• Examples include:
• samples that should be chilled during transport but that are received at room
temperature
• or specimens for anaerobic culture that are received after being exposed to
air
Sample Rejection
e- Hemolysis:
• Cell counts and certain chemistry analyses (e.g., potassium or LD)
will be adversely affected by the lysis of red cells.
• Hemolysis may result from a difficult venipuncture or from too
vigorous handling.
• A new sample should be requested
Additional Information
• In addition to the collection manual, the laboratory should
provide for the nursing and medical staffs information on
laboratory operations
• This information will facilitate smooth test ordering, result
reporting, and communication between the laboratory and
users of its services
• This information can be included as an introduction to the
collection manual
Additional Information
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Discuss the method by which to order tests from the
laboratory, including directions for ordering, both by manual
and by electronic methods
Include a list of tests offered by the laboratory
Provide information on how to request test results
Include telephone numbers to call and hours of operation for
each department of the laboratory
Present a list of the tests that are routine or stat (urgent)
Include a list of reference intervals
Describe the proper disposal procedures of needles and
syringes
list the proper collection procedure for infectious patients
Include color key for vacuum tubes, describe the additive
used for each test
Interaction With Patients and Other Hospital
Personnel
• Many times the only contact the public has with laboratory
personnel is the phlebotomist at the time of sample
collection
• It is important that the collector present a professional
appearance and have a courteous manner when
approaching a patient
• The collector must clearly communicate to the patient who
he is, why he is there, and what is required of the patient
• A relaxed and cooperative patient will more likely provide
an adequate specimen and correct information
Interaction With Patients and Other Hospital
Personnel
• The phlebotomist must "realize that he is an integral-part
of the health-care team
• An attitude of cooperation with the doctors, nurses, and
other health-care professionals is necessary to provide
high-quality health care
• Unclear instructions, duplicate orders, or conflicting orders
should be clarified or questioned before processing
• Unusual circumstances and significant events or
happenings should be reported to the nursing staff so as
not to jeopardize the patient's health
The Collection Process
• The first step in the collection process, be it venipuncture,
urine collection, or throat swab, is the proper identification
of the patient
• Outpatients should be asked for their name, not "Are you
Mrs. Ali?“
• An inpatient's identification bracelet should be matched
with the Specimen Request Form for name and hospital
ID number
• Misidentification of the name of the patient from which the
specimen is received may result in the improper treatment
to the wrong patient
The Collection Process
• Proper selection of the collection site is important in
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obtaining a valid sample
Certain blood chemistries have different concentrations in
the arterial as compared to the venous blood
Sites of infection need, to be properly sampled when
collecting culture material
The proper collection equipment and procedures are vital
for obtaining a valid sample
A listing of materials and their proper use should be
outlined in the collection manual in detail and included in
the procedure manual
The training checklist should include the use of the
equipment
The Collection Process- Sample Labeling
• The specimen should be labeled with the patient's name,
history number, date and time of collection, and the initials
of the person collecting the sample
• This information should be identical to that on the test
requisition
• If there is a discrepancy between the name or history
number on the sample label and that on the requisition,
the sample should not be processed until the difference is
resolved
• Some samples, especially those to be used for
crossmatches, should not be considered properly labeled
unless the collector's initials and the date and time of
collection are on the sample
The Collection Process- Sample Labeling
• But there are exceptions to some rules:
• In cases of extreme medical emergency, labeling protocol may be
temporarily waived
• If one can be certain that the problem is a clerical rather than a
substantive one, it would be improper to withhold results in a medical
emergency just because the sample was not properly labeled
• Hard-to-collect samples, such as cerebrospinal fluid, are
sometimes received unlabeled
• Delay in performing cell counts or culturing may result in the destruction
of significant cells or microorganisms.
• In cases such as this, a decision must be made whether to process the
specimen while attempting to identify it properly or to request another
specimen
• Withholding the results on the specimen until positive identification ofthe
source is one method of preventing incorrect reporting
The Collection Process- Sample
Accessioning System
• Once the sample and the requisition have reached the
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laboratory it should be processed immediately
At some point the sample and the requisition will be separated
A sample accessioning system provides a means of keeping
the specimen and the requisition together
As it enters the laboratory each sample is assigned a unique
number
That number is also placed on the accompanying requisition
As the sample and requisition become separated during the
sample preparation process, it is by this number that the two
can be united again
In laboratories utilizing computer systems to report results, the
accessioning number is used to log the test request into the
laboratory and to report the results in the laboratory computer
system
The Report Form
• In many institutions the test requisition also serves as the
test report form, especially in hospitals that are not served
by a hospital computer system
• The report form includes much of the same information
that the test request form contains.
• The report form should have the following information:
• Patient name and history
number
• Date and time the specimen was
collected
• Patient location
• Date and time the specimen was
received in the laboratory
• Patient diagnosis
• Date and time of the analysis
• Name of the ordered test
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• Ordering physician
Results of the analysis