Introduction of POCT
One of the most common diseases in the world today is diabetes. The statistics show that in the year 2000, it was prevalent in approximately 180 million people, and the figure is rapidly increasing and reaching epidemic proportions (1). This increase is constantly being associated with higher mortality rates. However, early diabetes and pre-diabetes screening may assist in the reduction of complications arising from diabetes. Point of Care Testing (POCT) is one way of bringing diagnostic tests and associated therapeutic actions to the patients, and thus aid in controlling the spread of diabetes (2).
POCT refers to any medical tests undertaken near or where patient care is undertaken (1). The main purpose of POCT is to conveniently and promptly make the test available to the patient. This way, it is easier for the care team, physician, and patient to get quicker results, and consequently making it possible for instantaneous medical decisions to be made. There are several tests that can be incorporated in POCT, such as: electrolyte analysis, blood glucose testing, rapid coagulation testing, haemoglobin diagnostics, cholesterol screening, and infectious disease testing (3).
For POCT to be effective, various instruments such as nerve conduction study device and blood glucose meters are necessary, especially since they are portable and easily transportable (4). In order for POCT to be more cost-effective, smaller, cheaper, smatter, and faster POCT devices are being applied for diseases such as acute coronary syndrome, diabetes, and carpal tunnel syndrome.
The main advantage of using POCT devices is the fact that one is issued with an electronic medical record immediately. These results can then be shared between all the relevant medical team members via the software interface (5). This in turn decreases the turnaround time. The use of POCT, the electronic medical records, and goal directed therapy techniques has the effect of reducing mortality and morbidity rates by a reasonable percentage.
Since there is a wide range of lancing devices and blood glucose meters for POCT testing, careful and thorough evaluation is mandatory so as to settle on the best option (6). The questions that need to be asked before settling on a specific device are:
a) Can the device be used by non-laboratory staff?
b) Is the device fitting for the projected setting?
c) Is the device made in regards to the surrounding environment?
d) Can the device be used on more than one patient at a time, or is it for just a single patient?
e) Does the device design suit the requirements of the user/patient?
f) Is the device easily transferable from the hospital to the POCT site?
g) Does the device have a suitable warranty or do you have to pay extra to get it?
h) Is the device CE patent under the IVD directive?
A recognized hospital laboratory can be approached to provide advice on various issues such as the acquisition of the devise, basic training, analysis of results, quality control, troubleshooting, and health and safety measures (2).
In order to choose the appropriate testing device, several potential ones have to be evaluated so as to settle on the best. These evaluations have been made in the excel sheet attached (Appendix 1). After evaluation, the HbA1+c devices rank as follows:
1) DCA Vantage-Number one
2) Afinion-Number two
3) In2it-Number three
4) A1cNow+-Number four
5) NycoCard-Number five
For HbA1+c, the best device to choose in regards to immunoassay is Afinion.
As for glucose testing, the device performances are ranked as follows:
1. DCA Vantage
2. Afinion
3. NycoCard
4. Hemo Cue
Therefore, the best device to settle on in regards to enzymatic reaction is DCA Vantage.
Policy for the POCT procedures
For POCT to be effective, suitably trained and certified nurses, physicians, and other qualified and certified technicians should be used to perform POCT procedures outside of the laboratory (7).
A set of guidelines must be set to ensure that the obtained results are clinically liable and they comply with the state and federal regulations as well as the relevant laboratory certification standards. These guidelines should clearly define the specific procedures that will be undertaken.
For every test to be undertaken at the site, a specific procedure will be followed according to the set guidelines (8). Failure to follow the outlined procedures will lead to termination of permission to keep performing those tests.
Quality control (QC)
The adherence of appropriate quality control measures is vital. Failure to incorporate quality control can give rise to solemn mis-interpretations of the test results (9). How the patient sample or QC sample is obtained is the most important step.
Therefore, a set number of quality control test samples should be run at prearranged intervals. QC samples contain a set concentration of the specimen being measured. This sample is analyzed the same way that the patient sample will be analyzed (9). A QC sample analysis should be done daily after daily maintenance and calibrations have been carried out, but before analysis of any patient samples.
Recording of QC, action limits and procedures to be followed with QC failure
After the analysis, the results are compared to the QC known value. These results have to fall within a range of 95-100% of the known values (1). If the QC sample results are wrong or are not analyzed, it must not be assumed that the final patient results will be accurate, or that the analytical process, analyzer, or the reagents are functioning suitably.
It is imperative to have daily recordings of the QC procedure, and any changes in the expiry dates of reagents, electrodes, and control values have to be documented and dated on the correct worksheets (10).
In case the QC fails or a parameter falls outside the given QC ranges, the operator should follow a set procedure to correct it (11).
1. Consult the provided Operators Manual for the list of frequent errors and instructions on how to fix them.
2. Repeat the QC analysis to confirm that the result is not just a random error.
3. Check to confirm that the QC sample used to repeat the test is totally thawed, and then mix it well.
4. Check the technique applied to rule out any overlooked factors such as sample being overly exposed to air before analysis is done or wrong calibration of the analyzer.
5. Check for incorrect lot numbers, wrongly elected QC level, or expired QC sample or reagents.
6. Evaluate the analyzer operation for any procedural errors.
7. Confirm whether there are any analyzer faults.
8. Document all efforts to resolve the said problem on the Error log sheet provided.
However, the analyzer or process for the patient results must not be used until successful QC sample results have been obtained.
Instructions for the recording of results
All POCT equipment operators must be highly competent and have a duty of care to make sure that the results generated are precise and accurate (12). For the POCT results to be put into the patient’s medical records, they have to be declared in the POCT procedure for easy tracing. The result reports should contain at least two patient identifiers such as the patient name, ID, date of birth, testing date, the time of the test, the results obtained, the QC results, operator’s identity and any other important factor. This way, it is hard to record the wrong results for the right patient.
Before recording unexpected or extreme results, they must first be re-checked by conveying a sample to the laboratory.
Operator training and on-going competency assessment
All technical and support staff required to use the POCT equipment must receive training regarding the use of the equipment (13). The POCT coordinator is responsible for ensuring that there is an appropriate training and documenting program for his staff. The training program should incorporate:
The collection, movement, and disposal of the relevant specimen
The Quality Control necessities
The step by step procedures to be undertaken
How the results will be recorded
How the results will be interpreted
Troubleshooting
How to maintain the equipment
Competency assessment:
Upon completion of training, all the trainees should be accessed through a written and practical test to ensure that they are amply prepared to perform the tasks required of them. All successful trainees should then be awarded a certificate of competency after completing their formal training (2).
All staff given the responsibility of handling the POCT equipment must provide up to date audit/competency records to the POCT coordinator (3). Competency is then reviewed for all the POCT, either annually or every six months. These reviews should include quality assurance and quality control testing results.
Internal QC (IQC)
This is performed daily or at a specified interval as set by laboratory technicians. The staffs in charge of using POCT are required to perform, record, review, and action QC results (14). IQC is necessary to make sure that all patient results are deemed reliable before actually being handed to the patients. Manufacturers usually provide a control material that is usually used in analysis of the tested sample, which serves to provide reassurance that that particular device is functioning faultlessly (4). In case the results obtained are not within the accepted standards, the hospital in charge should investigate why the results turned out that way, and get solutions for the same.
Acceptance testing should also be practiced especially for new consumables and devices to ensure that they are functioning within the set standards (5). Moreover, there should also be set guidelines for those in charge of interpreting the results, and a defined set of procedures for dealing with results that fall out of the accepted QC range.
External quality assessment (EQA) procedures
POCT must have a certain level of quality assurance that is dictated by the relevant Health Laboratories. A suitable QC programme has to be agreed on and documented in order to be adhered to (13). To ensure that POCT results are comparable to those of the relevant Health Laboratories, a system has to be put in place.
External QC (EQC)
These programs are undertaken by appointed clinical staff at set time intervals as dictated by the laboratory. Dedicated External Quality providers can also be used for their input (6). EQC is mainly applied in cases where samples provide unknown values that have to be rechecked by an external source. These results have to be assessed by peer group assessors and other statistical analyzers in order to compare different results that have been acquired (13). All POCT users are required to take part in EQA schemes so as to perform sufficiently according to clinical governance.
Instructions for patient preparation
Only staffs that have been given ample training are allowed to perform POCT. In order to enhance efficiency, all staff in charge of patients must have the ability to correctly identify patients, properly analyze patient samples, ensure that the analyzer is calibrated properly, analyze the quality control samples, undertake required procedure maintenance, document all acquired results, and pass all competency tests given (15).
Before any tests are undertaken, every patient must be given their own unique ID. This must be a unique number that has never been given to anyone else.
Before a sample is collected from a patient, the area from which it is being obtained must be dry, clean, healthy, alcohol free, and free from any contaminants (2). Since the quality of the results is determined by the quality of the sample, it is imperative to always:
1. Wash your hands before handling the patient
2. Wear gloves whenever handling a patient
3. Wear protective clothing if handling infectious patients
4. Disinfect the sample area before taking the sample
5. Wash your hands after handling the patient.
All POCT procedures have to be approved by the relevant clinical staff (14). All the relevant patient information has to be recorded either on paper or electronically. Moreover, all collected samples have to be properly labeled with the respective patient’s ID to avoid switching (7).
Written operational instructions and what these should include
Anyone given the responsibility of handling POCT must be well aware of all the manufacturer’s instructions in regards to the device, especially when it comes to: performance, intended purpose, results interpretation, scope of use, sample requirements, reagent and sample storage, sell by dates, quality assurance, and potential health and safety issues (8). These instructions should be clear, precise, and in an understandable language.
Standard operation procedures are necessary and should be provided to everyone involved in POCT. These procedures must be regularly updated (9). The main points to consider when it comes to these operating procedures are:
a) Ensuring that these procedures are written and produced in regards to the set quality standards.
b) Ensuring that these procedures are readily available to all intended users at all times.
c) Making sure that these procedures have the necessary procedures for infection control where needed.
d) Including the manufacturer’s instructions in these procedures.
e) Constant review of the procedures to suit the changing times.
f) The availability of all the information regarding handling of acquired results.
g) The relevant steps to be followed should the devices in use breakdown or become faulty.
Device maintenance and performance records
All POCT equipment is required to have a documented maintenance schedule (9). This is to ensure that backup is available in the event of a breakdown. Therefore, anyone in charge of these devices should be very well aware of the set of instructions from the manufacturer in order to ensure proper troubleshooting techniques (1). There should be a set of instructions for maintenance of every single device so as to ensure effective maintenance.
Regular maintenance checks should also be carried out, either weekly or monthly, to ensure that all reagent records are at par with the manufacturer’s instructions (10). In case of a complex problem or breakdown of the equipments, there should be a clearly defined procedure of how to contact the manufacturers and inform them of the problem. However, adverse events should be reported to the MHRA (11).
Post implementation follow-up and confirmation of performance requirements
The laboratory director must be able to identify any areas that require improvement by monitoring quality indicators (12). These indicators include: QC indicators (documentation, number of errors, QC statistics, and any failed QC samples); Utilization indicators (tests charged versus tests used, used reagents, and QC applied) and Compliance indicators (expired reagents, untrained operators, data entry errors, and addressing errors in good time).
Regular In house critical review should also be performed to evaluate all the active POCT parties in regards to a performance checklist. Corrective actions should also be carried out to ensure optimal performance of all involved parties (3). In addition to that, optimal analytical performance tests should also be carried out to ensure POCT effectiveness.
Patient safety and risk management
All POCT tests and procedures should be conducted in such a manner that does not compromise the safety and well being of both the patient and the operator. Therefore, all devices must be operated in accordance with the manufacturer’s instructions. Moreover, all device components must always be checked for safety prior to their use (14). Furthermore, all the devices must be properly cleaned as par the manufacturer’s guide, with careful reference to the proposed times and manner (4).
Gloves must always be worn during the collection of patient samples, and must be changed and hands washed between patients at all times regardless of the procedure being carried out (5).
Additionally, the work area must be cleaned daily and any spilt body fluids must be wiped immediately. The work areas must always be cleaned using hot soapy water, and thorough scrubbing must be done to completely remove any present micro-organisms. Decontamination must also be done after every wash-up session (13).
All used reagents, gloves, samples, needles, syringes, cotton wool and swabs must be disposed immediately after use to avoid cross contamination between patient samples.
Conclusion
POCT has become a basic standard of care worldwide. Its benefits such as reduced operating times, swift decision making and triage, reduced high-dependency, reduced emergency room time, reduced operating times, reduced emergency room visits, reduced outpatient clinic visits, less numbers of hospital beds occupied, and the optimal use of professional time have made POCT very favorable (15). Therefore, more effort and funding should be put into encouraging extensive use of POCT, since its benefits are truly worth it.
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