Introduction
One among the fields that have profited from the rapid technological progress in the previous centuries is the field of medicine. Conditions and Diseases that scientists had trouble in understanding and curing are now cured successfully and with virtual ease. More people as well as the incurably-ill now survive longer than before. Development in the global population has been distinguished in the 20th century. The old and young population has increased pressure on medical care resources internationally with the intention that no nation is currently capable to compete with the demand for medical -care and its supply. Scientists hence are under growing pressure to extend fresh technologies to raise consumers prompt access to medical -care
A most noteworthy and ground-breaking progress in the field of medicine has been development of point-of-care testing. Consistent with (15) POCT is described as patient samples examination at or close to the patient carrying the supposition that test outcomes will be obtainable instantaneously or within an extremely short timeframe thereby helping caregivers in the instantaneous diagnosis and medical intervention(26) .Point-of-care testing is performed away from the traditional central laboratory setting , and has created easier self-management as individuals can examine themselves and react to the outcomes as counseled by their doctors. POC testing machinery is vital to the accomplishment of life-saving and disaster management undertakings as assessments can be conducted in intensive care units or in an ambulance where judgments are time-susceptible.
As mentioned, POCT is regularly executed outside of the clinical laboratory and carried out by non-laboratory staff. Therefore, it is obvious that the consistency of POCT relies wholly on the practical performance of POCT strategies totaling to compliance with treatment procedure (12). This means that the Quality of sample that is, acquiring the right form of specimen is essential to attaining accurate results. In contrast to central laboratory testing, it is obvious that the dependability of POCT is not as reliable owing to three different reasons. These include personnel, environment, and devices (1).
In a central laboratory setting, the tests are carried out by competent laboratory personnel who have sufficient abilities to carry out any kind of examination necessary on any given sample. From this reason, there is a great chance that the performance of central laboratory testing is more reliable (13). Looking at POCT, the personnel are usually of non laboratory origin. It is usually performed by nurses who may have little or no laboratory experience. Therefore, the procedure though basic could be undermined and thus less reliability. From different readings, mistakes made by such employees can be observed in sample anthology wherein heamolysis can be realized in whole blood samples in form of ruptured red cells throughout specimen collection thus causing augmented potassium and other analytes in the samples thus false results and less reliability(22).
Another issue that can be related to personnel and touches on reliability of the performance of POCT is giving an Additional task to a non laboratory staff who is already busy with his or her work. Therefore, these practitioners may not enthusiastically carry out the extra work that involves assessing patient samples on top of quality control and official procedures. Consequently there might be deficiency in audit trails or traceability. When specimens are examined inside the laboratory setting, usually an auditing tried-and-true system is already in position (3). However, with POCT, it falls to a full of activity nursing personnel to preserve an audit follow up of their outcomes and to preserve precise daily maintenance records, quality control, troubleshooting and operator and patient ID. This adversely affects the reliability of POCT as compared to Central laboratory.
Direct comparison of POCT and central laboratory results and possible reasons for discrepancies results
It should be noted the results of POCT and central laboratory are most likely to be different. Therefore direct comparison of the results could cause a difference in the interpretation of the results. For instance, on a study conducted by (4), a constant disparity between central laboratory results and POCT results for regular electrolytes was observed. This was hypothesized to be owing to the conflicting volume ratios of the anticoagulant applied to patient specimen employed in POCT mechanisms against that employed in central laboratory examinations. On the Other hand, this does not completely explicate the disparities in dimensions linking both methodologies (23-25). When central laboratory testing residual plasma was assayed via the POCT methods, these disparities still lingered. This may reproduce authentic disparities in sensitivity, accuracy and bias. Consequently the potential reason for the disparities could be that POCT outcomes could be considerably influenced by pre-analytical variables for instance fibrin clots inside the sample, heamolysis, and insufficient amalgamation of the sample with anticoagulant (17). Other dynamics that could add to abnormal results incorporate blood samples polluted by ambient air and the utility of expired stored cartridges. With indirect POCT mechanisms, the exploit of plasma against serum could make a noteworthy dissimilarity in potassium dimensions, with values from serum constantly being elevated than plasma, owing to potassium freed throughout clotting.
Skill requirements for POCT personnel
The Point-of-Care course has been established to ensure strategies, measures and apparatus used are permitted by the Coordinator of Point of Care prior to executing. Training procedures and competency necessities are concluded prior to the examining staff performing trials. Quality Control report and ability results are assessed to determine fulfillment. Examining employees shall be instructed by the coordinator or a qualified designee from Point-of-care for Point-of-Care testing (14). On completion of the training, the persons shall acquire the following: expertise required for appropriate sample collection, Patient preparation ability, classification and appropriate management of reagents to comprise date obtained, expiry date and date in use, proficiency required for executing procedures, ability required for carrying out each examination method and good use, working information of reagent strength and storage, proficiency required to apply the quality control guiding principle and course of actions, knowledge of factors influencing test end results and ability required to evaluate and authenticate the soundness of patient test outcome through the assessment of quality control specimen values before accounting patient test end results (20).
Improving performance of POCT
Specimen quality is debatably weakest link in POCT chain. A specimen of deprived quality denotes outcomes of poor quality (19). It is therefore a major section whereby in order to improve POCT should be look at. In order for the quality of samples to be high, the POCT program should be integrated well with the central laboratory testing program. This will enhance better communication and share of expertise in order to aid in improving POCT performance (9). In addition to this, it would be best for the POCT program to higher laboratory staff who can carry out the tests in the field. This reduces the chances of sample collection blunders that can results in false results (11).
Above all the outlook of POCT relies, partially, in realizing the data management challenge. As the industry carries on to grow, there is a mounting requirement to border data from handheld examiners and checks with individual patient documentations and the central laboratory. Examination outcomes from POCT machines are habitually transliterated by hand towards the patient record with modest, if any, technique to recall data at an afterward time or incorporate into hospital information structures. Kost suggested comprehensive connectivity and information capture is the millennium challenge for POCT (30).
Conclusion
POCT is testing executed in clinical surroundings by non-laboratory experts outside the laboratory. In recent times there has been a huge development in the diversity of tests carried out by POCT. These comprise tests executed in Immunology, Biochemistry, Microbiology and Hematology Laboratories. Shifting clinical applications are as well resulting in more widespread exploit of POCT. There are benefits of POCT in relation to traditional laboratory testing. For instance, outcomes are obtainable more rapidly as transporting samples time to the laboratory is greatly reduced. This is especially fundamental when treating gravely ill patients. In addition, in a number of out-patient surroundings, specifically, POCT outcomes can be employed to alter patient’s medication resultant in the expediency of less recurrent clinic meetings.
However, there are as well drawbacks with POCT in relation to traditional laboratory testing like the cost per test being more exclusive for POCT. as a result, a fresh POCT service ought to provide important patient remuneration to acertain partial NHS funds are used properly. The quality of outcome can also be influenced by insufficient training or unsuitable use of mechanism. All diagnostic examinations, whether executed inside the laboratory or outside the laboratory, may run into troubles, for instance, a new drug might interfere with an examination and there after cause measurement faults. Laboratory personnel have more information and skills to distinguish and deal with these forms of circumstances. In other terms, it is vital to obtain the balance accurately and capitalize on the benefits exciting technologies obtainable while ascertaining the results quality of the patient safety is not put in jeopardy. This is realized by encompassing a POCT maintained Service united through a Trust POCT Policy and multi-disciplinary POCT committee. The POCT maintain Service offered by Laboratory Medicine comprises of structured training series, procedure for inspecting and filing the proper performance of the mechanism, regular ability testing methods for employees to display their unrelenting skills obtained during training; quality assessment to recognize possible problems with recommendation and troubleshooting if a few are established.
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