Abstract
Physicians worldwide prescribe anticoagulation therapy to treat and prevent blood coagulation. However, this therapeutic intervention has a narrow window, which requires the patient to frequently monitor the international normalized ratio (INR) to minimize thromboembolic and hemorrhagic complications. The point-of-care (POC) and laboratory-run (LRT) testing are the two anticoagulant measurement approaches through which patients routinely observe the prothrombin time for clinical decision-making. Although POC tests are widely used due to their rapid turnaround time and convenience, users are advised to periodically validate the results obtained from the self-assessment with the findings of a standardized and automated laboratory. This paper evaluates the population, intervention, comparison, and outcome (PICO) aspect of the two anticoagulant measurement approaches particularly regarding the effectiveness, validity, and confidence levels of their results.
Introduction
Anticoagulants are medications prescribed by physicians to prevent or eliminate the risk of blood clotting. People with the likelihood of blood coagulation are highly susceptible to developing life-threatening conditions caused by the blockage of a vein or artery supplying blood to critical boy organs. Doctors recommend anticoagulants to people presenting various specific conditions, including abnormal heartbeat and blood circulation challenges, among others. Although these medications are essential in preventing and reducing the progression of thromboembolic disease, physicians recommend regular blood tests known as the international normalized ratio to determine if the anticoagulants are at the correct levels. In this regard, patients under anticoagulant therapy require consistent monitoring to ensure they are getting the correct amount of medication and are not exposed to risks of blood clotting or bleeding. Point of Care (POCT) and laboratory-run tests (LRT) are the primary methods through which physicians ensure the right balance of the anticoagulants. Although POCT (I) provides patients (P) faster turnaround time, convenience, and minimal blood loss, LRT (C) generates considerably comprehensive results (O) for clinical decision-making.
Population
Blood clotting is a fundamental process which prevents the excessive loss of blood after an injury. However, some people experience coagulation on the inside of the blood vessels even without incurring any bruises. This situation poses a significant danger of serious complications, such as heart attack and stroke. Wendelboe and Raskob (2016) contend that thromboembolic conditions are a leading cause of mortality and mortality and account for one in four deaths globally. In this regard, patients presenting blood clotting problems in the absence of an injury require correct diagnosis, appropriate treatment, and accurate monitoring of the provided medical interventions. Physicians prescribe anticoagulants as the cornerstone approach in the prevention and control of coagulation occurring within the veins in the absence of an injury. According to Czuprynska, Patel, and Arya (2015), the management of this condition poses is challenging to patients since the current interventions encompass an inherent risk of bleeding, which should be counterbalanced by the anticoagulant activities of each drug. The optimal balance of these elements can only be achieved through regular monitoring and testing through POCT and LRT to mitigate adverse outcomes.
Intervention
Patients undertaking anticoagulation therapy require regular testing and monitoring to ensure the right amount of medication and reduce the likelihood of adverse implications, such as blood coagulation and excessive bleeding. The point-of-care (POC) and peripheral blood draw laboratory-run anticoagulant (LRT) testing of the international normalized ratio (INR) are the two current anticoagulants management models. The former is a patient self-monitoring tool in which they are trained to effectively assess their INR by using provided POC systems and adjust their anticoagulant dosages accordingly. Conversely, the peripheral LRT is an assessment of the amount of anticoagulant that takes place within the laboratory settings of a hospital establishment. This implies that this measurement is conducted on the patient by professionally skilled healthcare workers during their regular clinic visits. Similar to POC, the primary objective of LRT is to optimize the anticoagulant levels by ensuring that over or under-dosage does not occur.
Point-of-Care Test Results
The POC testing is a self-administered monitoring exercise in which patients undertaking anticoagulant therapy are trained to monitor their INR regularly and adjust their dosage. Under this model, healthcare workers train their customers to effectively conduct tests as an alternative and simplified approach to conventional laboratory testing. The INR results are determined from the whole blood assessment obtained through a finger puncture. A distinctly prominent feature of this evolving POC system is its ability to generate INR results within minutes. Moiz et al. (2018) note that POC tests’ usage is growing rapidly due to their ability to support swift clinical decision-making and rapid therapeutic turnaround time. This helps the timely evaluation of the outcomes for subsequent utilization in dosage adjustment and prompt consideration of other critical values.
Peripheral Blood Draw Laboratory-Run Anticoagulant Test Result
Laboratory-run anticoagulant tests are the regular monitoring procedures for the optimum levels of medications prescribed to patients. Unlike the POC test, this assessment takes place within the confines of a laboratory facility in a healthcare setting managed by professionals. There are various disparities in the results obtained from the POC systems and those generated from a process administered by a clinician. Notably, the outcomes from the lab procedure are significantly standardized due to the application and utilization of structured and uniform processes. However, the variations in electrochemical and reagents may substantially contribute to disparities in the results. Palaparti et al. (2020) argue that different instruments, degrees of sample dilution, varying approaches to clot detection, and pre-analytic delays are fundamental factors which sway the accuracy, consistency, and correctness of the results. For instance, blood samples drawn from the same patient but analyzed in different laboratories may manifest notable disparities in the INR due to the operational disparities in the various hospitals.
Comparison
POC and LRT are widely used anticoagulation management models by testing the INR to support clinical decision-making. The two approaches are designed to provide valuable insights to the patients and clinicians regarding the appropriate course of action in adjusting the anticoagulant dosage. However, there exist significant disparities, particularly in the results obtained from POC and LRT tests. These variations are attributable to the different operational mechanisms of the two approaches and the effect of extraneous factors, such as the duration after which the obtained blood samples are analyzed. For instance, the absence of effective quality assurance and controls in POC tests significantly erodes the degree of confidence and exposes the model to defects (Moiz et al., 2018). This implies that the findings obtained from the self-monitoring should be regularly evaluated and validated against the LRT system, which bears a robust mechanism for eliminating errors and flaws.
The success of the self-management model relies significantly on the reliability and accuracy of the POC systems. Although the devices have in-built internal control mechanisms designed to ensure the proper functionality of the reagent and instrument, they lack external quality regulatory structures. This implies that variability in POC testing may be experienced, reflecting the diverse abilities of the user, patient biases, and other extraneous factors such as pre-analytic delays (Arline, Rodriguez & Sanchez, 2020). Additionally, the accuracy of the results is significantly influenced by the customer’s motivation and cognition levels of the instructions, guidance, and directions provided by the healthcare practitioners (Palaparti et al., 2020). Also, some patients may experience challenges in interpreting the values of the outcome of the tests. Behavioral issues, such as patients’ attitudes, stress, discerning how to act promptly, and perceptions about the self-monitoring instruments are critical and directly influence the findings. In this regard, retests and reevaluation of the systems are often required to establish the device’s effectiveness against laboratory methods and the consistency of the results before adjusting the anticoagulant dosage.
Conversely, the LRT results are relatively standardized due to the considerable degree of uniformity in the methods and procedures. Notably, any emerging disparities between the outcomes of various laboratories can be explained by evaluating factors such as the extent of sample dilution, electrochemical properties of the reagents used, and delays in the pre-analytic phase. Additionally, the interpretation of the results is substantially uniform and standardized and is not impacted by extraneous elements such as the cognition and motivation levels of the healthcare professional. Also, the outcomes of the laboratory monitoring are modulated by the internal control systems, which ensure the proper functioning of the instruments and reagents. This regulatory mechanism is absent in POC testing, which has necessitated providing advice for patients to periodically and regularly check their INR from a laboratory. For instance, clinicians and their instruments are unlikely to be apprehensive, demotivated, and affected by personal or behavioral issues, which would influence the proper timing, attitude, and interpretation of the findings. Notably, the differential results directly impact clinical decision-making, and any errors could endanger the patient’s life.
Outcome
POC and LRT tests are the two widely used models for anticoagulation management to test the INR for clinical decision-making regarding dosage adjustments. The self-monitoring approach provides faster turnaround and therapeutic times, convenience, and eliminates the need for the patient to visit the hospital. Clinicians train the customers on how to personally administer the test effectively whenever the need arises. Conversely, the LRT model is a relatively standardized and automated anticoagulant measurement method conducted by a professional within a healthcare facility. Notably, the results obtained from the two approaches differ significantly due to the variations in the operational disparities, personal biases and perceptions, timing, and motivation. Comparatively, the POC findings are susceptible to subjective factors, such as the attitude and perception held by the patient about the instruments. Additionally, the absence of robust quality control and assurance system adversely impacts the validity and reliability of this model. Conversely, the LRT method is a standardized and automated system which is not influenced by extraneous factors. Therefore, this approach provides considerably valid findings which can be used for clinical decision-making without the patient experiencing adverse outcomes.
Timeframe
Although POC is considerably comparable to the LRT test, the primary difference is in the turnaround timeframe of the two approaches. Notably, POC provides rapid determination response of INR for clinical decision-making since there are no pre-analytic delays or procedures to be conducted. Wool (2018) asserts that transportation convenience provided by the POC significantly improves procurement and eventual utilization by the end-users. Additionally, the administration of test entails fewer steps than standard automated laboratory tests. Thus, POC provides a shorter timeframe for turnaround and results generation compared to LRT.
Conclusion
Anticoagulants are critical medications prescribed by physicians to manage blood clotting and eliminate the risk of the associated implications. Although the former provides rapid results, convenience, and minimal blood loss, the generated results require to be validated by standardized and automated laboratory tests. In this regard, the findings of the POC tests should be evaluated against the laboratory outcomes for better clinical decision-making and the prevention of adverse outcomes.
References
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