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Test tubes, pipettes and calorimeters were used extensively in early forms
of biochemical analysis. Generally, such analyses were performed under
the condition without protein matrix, so deproteinization was essential.
In the 1970's, automatic analyzers emerged, and the processing performance
and precision of analyzers was increased. Even though there were still
limitations on automation (a need for conducting deproteinization), laboratories
installed automatic analyzers to improve the efficiency of laboratory operations.
In the latter half of the 1970's, enzymatic analyses were introduced, thus
rendering deproteinization unnecessary, and this increased the selectivity
of mixed component analyses such as biochemical tests. This advancement
in analytic methods further accelerated the development of automatic analyzers.
The sensitivity of automatic analyzers improved, and once analyzers were
capable of utilizing micro amounts of specimens, parallel analyses became
possible and multiple-task automatic analyses became easier to perform.
As a result, in the 1980's, automated laboratories began to aim for the
systematization of analyzers. Even though some people have stated that
the emergence of multiple-task analyzers contributed to systematization,
I believe that systematization was propelled by the fact that physicians
who request tests are not aware of the different fields of laboratory analyses.
Consequently, instrument manufacturers also began to design analyzers that
were suitable for systematization, but analyzers that were mainly designed
for laboratories were limited to their predesignated field. Furthermore,
since systematization was achieved utilizing analyzers with limited adaptability,
the process was never quite complete. Consequently, the development of
the systematization of automatic analyzers was neglected in Japan. However,
starting in the latter half of the 1980's, automatic analyzers equipped
with a transportation system started to appear, and when the systematization
of an entire laboratory was required, the construction of automated systems
was accelerated. Nevertheless, from the standpoint of quality control,
the concept of a system that manages the flow of tests (beginning from
blood collection and test requests) in a laboratory within a central medical
center is still relatively new. In the present article, I will focus on
laboratory automation systems that are used as tools to ensure quality
control.
A. Construction of laboratory automation systems from
the viewpoint of laboratory management
Figure 1 shows the flow diagram of laboratory tests. Although the systematization
of clinical laboratories basically follows the figure below, from the viewpoint
of laboratory automation systems, the emphasis is on the cyclic flow of
laboratory procedure from specimen collection to test result management.
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| Figure 1. Test flow and monitoring points |
1. Test request and specimen collection
1.1 Establishing the communication pathway for test requests
In the past, vouchers were often used to ensure the reliable transmission
of test requests. When a laboratory information system is operated alone,
input data must be checked several times in clinical laboratories. This
wastes a great deal of time, and even urgent requests can not be handled
promptly in some cases. Therefore, if requests that are checked by doctors
during test planning can be sent to a laboratory via the informational
system of a hospital, then time will not be wasted by unnecessary conformation
procedures, and test results can be delivered even more promptly. This
problem should be addressed by separating clinical laboratories that are
supported by a hospital information system and those that operated standalone
as laboratory information system. Also, it is important to keep in mind
that laboratory automation systems must be supported to their hospital's
medical information system in the future.
a. When a laboratory is not supported by a hospital information system
Automatic information input machines such as scan-tron sheets should be
utilized.
Nonetheless, the following points must be considered:
- Reliable transmission of requests
- Reducing the time loss prior to actually beginning analyses
As to the latter, laboratories can assist nurses by processing request
vouchers the day before and preparing blood collection tubes beforehand.
Also, by processing requests the day before, analyses can be performed
with a certain degree of flexibility, and fewer mistakes are made.
b. When a laboratory is supported by a hospital information system
Requests can be reliably transmitted since they are sent directly from
a terminal. If test planning is also supported, then the efficiency of
the entire system would increase further, as long as the terminals and
the laboratory information system are properly linked. In some institutions,
this link is not adequate. In addition to efficiency and labor-saving,
the reliability of laboratory tests should also be reexamined in relation
to their economic viability.
1.2 Specimen collection support
Specimen collection should be supported by providing information such as
collection volume, how to collect, what kind of container should be used,
which are obtained from a test plan or request, to nurses and doctors.
If a medical information system is linked, then this support is easy. When
a clinical laboratory is supported by a medical information system, a specimen
collection schedule and labels can generally be issued in a ward or a blood
collection room at the same time a test plan is formed or a request is
made, thus aiding workers in charge of blood collection as a part of the
overall medical care support system. Nonetheless, when a laboratory is
not supported by a hospital total information system, laboratory personnel
can assist those in charge of blood collection by processing the necessary
data the day before. This operation can be done in various ways such as
the use of scan-tron.
Of the various types of support for specimen collection, the labeling of
specimens at the time of blood collection is important. Even if there is
no assistance from a hospital total information system, by processing test
requests in advance (reservation), blood collection steps can be supported
with the help of a specimen collection schedule by issuing labels in a
clinical laboratory and delivering them to a site where blood samples are
collected. In institutions where a hospital total information system and
a laboratory information system are soundly linked, specimen collection
is reliably achieved.
2. Management from specimen reception to analysis
The procedure in which a specimen is collected and delivered to a laboratory
for analysis will be important in future laboratory information systems.
The organization of laboratories that are recommended for systematization
makes the flow of specimens smooth (between the time a test plan is formed
and when the specimens are delivered to laboratory reception). Nonetheless,
it is also helpful to achieve the following:
- the implementation of an individual time-series specimen management method
and a one specimen one ID system (this is important not only for performing
simple data checks, but also for forming laboratory plans);
- the implementation of a central blood collection system for outpatients,
and the establishment of a delivery system in which specimens are promptly
delivered from blood collection terminals to a clinical laboratory (a central
blood collection system forces patients to walk to a blood collection room,
so a greater burden is placed on patients);
- the implementation of a prompt specimen reception system (in this system,
when specimens arrive at a laboratory, requests have already been processed,
so that analyses can be started at any time). When the implementation of
this type of system is not achieved, a laboratory can not process requests
promptly.
- the implementation of automatic analyzers that can send and receive test
requests, online transmission of analysis data, real-time monitoring and
a quality management system are important for quality assurance.
- llow a laboratory to handle randomly labeled specimens. In other words,
specimens that are delivered to a laboratory are already labeled where
blood samples are collected, so the numbering system is completely random.
As a result, a laboratory information system must be designed to handle
this type of random labeling.Even if a laboratory information system is
not linked to a hospital total information system, by processing test requests
in advance (reservation), the necessary labels can be printed out daily.
In addition, if an automated analyzer is capable of reading these labels,
then randomly labeled specimens can be delivered directly to the analyzer.
Even if an analyzer is incapable of reading labels, with the help of a
laboratory information system, the sequence of necessary tests can be ascertained,
and if the analyzer controls a specimen rack, then the analyzer can direct
specimens in the proper direction. In any case, if analyses can be performed
without worksheets, then time can be saved by not preparing worksheets,
thus improving the speed of tests.
All recently developed automatic analyzers can read bar codes, so an organized
code of numbers must be established.
- The maintenance and enhancement of analysis management and monitoring with
a total understanding of the performance of analyzers is important from
the viewpoint of quality assurance. In particular, it is impossible to
monitor multiple-task automatic analyzers manually. As a result, feed-back
regulation (retest) and the real-time inspection of test results must be
performed automatically.
Within a clinical laboratory information system, automatic analyzers should
be considered as components of the system. Since automatic analyzers are
rarely used alone in a clinical laboratory, they should feature real-time
functions to monitor laboratory data and to perform quality assurance.
3. Establishing the relationship between monitoring and action
Along with advances in automated analyzers, the monitoring functions of
analyzers are getting more refined. Nonetheless, monitoring that can not
determine actions based on the results of monitoring is not monitoring
anything at all. Table 1 summarizes the various steps of monitoring. The
following monitoring and action patterns are necessary:
| Monitoring |
Action |
| Analytic procedure |
- |
Deviation from dynamic range
Inspect latest previous value |
Dilute and analysis
Establish dilution time |
Zero-order reaction monitoring
High
Low |
Dilute and reanalysis
Increase amount and reanalysis |
| Cross contamination |
Simple reanalysis |
| Interference |
- |
Interference caused by in vivo
compounds
Interference caused by in vitro
compounds
|
Eliminate interference
Eliminate interference
|
| Result analysis process |
- |
Inter-item inconsistency
Poor pathological confirmation
|
Additional analysis of related item
Additional analysis of related item to
confirm patient physiological state |
Actions in response to test results anomalies must be coordinated with
physicians.
(1) Dynamic range deviation and reanalysis
Increasing numbers of automatic analyzers are equipped to carry out specimen
dilution and reanalysis. It would be ideal for analyzers to conduct reanalysis
by controlling dilution time. The dynamic range of analyses such as immunochemical
tests is especially large, so these analyzers should be designed to be
able to dilute specimens any times.
(2) Monitoring zero-order reaction
When zero-order reactions can not be assured in tests such as enzyme activity
measurement, if the activity is high, then the specimen must be diluted,
and if the activity is low, then additional amounts of the specimen must
be specified and the test must be conducted again. Along with the scope
of monitoring, it is also important to ensure accuracy within the reference
intervals.
(3) Gathering latest test results and predicting dilution time
Reanalysis prevent the smooth operation of clinical laboratories. When
the results of the latest test are too high or too low when compared to
those from previous tests on the same individual, a system can be designed
to instruct an analyzer to increase specimen amount or decrease specimen
concentration. This function should be included to improve the efficiency
and economy of laboratory tests.
(4) Avoiding cross contamination
The cause of cross contamination is attributable to the sampling mechanism
of automatic analyzers. The degree of interference should be investigated
and incorporated into the retest mechanism of each analyzer. Nevertheless,
it is important to minimize interference by improving sampling methods.
4. Management and analysis of test results
As stated above, it is important for automated analyzers to monitor analyses
and test results so that appropriate actions can be taken. However, the
results of analyses should also be the subject of monitoring and action.
In this type of monitoring, although the participation of experienced laboratory
technologists and clinical laboratory physicians is necessary, systematization
must also be considered.
(1) When the consistency of various analysis data from the same analyzer
is questioned, or when the consistency of data among different analyzers
is questioned, all tests must be conducted again or all necessary items
reordered.
(2) Most of today's automated analyzers have a function for receiving
test requests. This is an important function to ensure reliable transmission
of information (requests) that is generated within a laboratory information
system to analyzers. In addition, if analyzers can process the results
of retest and can automatically add and perform necessary analyses, then
test results can be delivered in a more timely manner. However, this requires
the total cooperation of clinical physicians.
(3) Furthermore, most analyzers can transmit test results online to a laboratory
information system. Once the test results are transferred to the system,
they can be compared with the results of other analyzers, so it is theoretically
possible to set up a process that would check contradicting test results
for retest. Therefore, a system that allows the adjustment of timing of
various analyses would be desirable.
(4) Nonetheless, these functions force automated analyzers to perform too
many tests in some cases, thus extending the turn-around time of tests.
Hence, it is necessary to collaborate with laboratory physicians to regulate
these monitoring functions as a supporting system.
5. Management of data from individual patients
The blood samples of a patient that are collected at the same time are
managed by the same label. Therefore, test results become more valuable
when they are organized to enhance quality control within a laboratory
information system. The following must be realized to manage patient data
more effectively:
(1) Test results must be inspected by well-trained and experienced
laboratory technologists, and a system that allows this checking mechanism
should be implemented.
(2) Implementation of laboratory data management by laboratory specialists.
(3) The effective utilization of accumulated test data as research sources.
Although it is very important to utilize accumulated test data for treatment,
it is more important to establish a system that enables physicians to utilize
it for research. As it is necessary to determine how to accumulate and
utilize accumulated data, this should be further evaluated in the future.
(4) Implementation of added value to test results
Furthermore, test results that are used in research add value to new test
results, thus establishing a recycling loop as a means of medical support.
At present, the most important task is to add this function.
Even though these points are important, a link to a hospital total information
system is desirable, or necessary in some cases.
B. Conclusion
The turn-around time of tests is getting shorter because of the advances
in automated analyzers and laboratory information systems. It is thought
that when a laboratory information system is established to provide quick
responses in actual medical situations, the importance of clinical laboratories
will continue to increase. Laboratory information systems are expected
to achieve this. On the other hand, it is becoming increasingly necessary
to organize expanding laboratory information as a part of hospital's total
information. These developments in laboratory information systems can potentially
change the way in which medicine is performed, and laboratory performance
should be maximized. Clinical laboratories should not just be a place where
laboratory data is generated, they must also be designed so that accumulated
data is effectively utilized for bed side research and recycled for medical
care.
References
(1) Takashi Kanno. Knowledge intensive laboratory information
systems that utilize a medical information system. Shin Iryo: 66 -
71, 1989 (2).
(2) Takashi Kanno: Current state of laboratory information systems
and their future development. Shin Iryo: 36 - 39, 1991 (2).
(3) Takashi Kanno: Future laboratory information systems. Sysmex Journal.
19: 145 - 150, 1996.
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