Intraoperative point-of-care testing

Point-of-care devices offer an increasing number of analytical tests more quickly than laboratory analysis, but clinicians must be aware of the limitations of these devices, especially for critical threshold-level decisions. Glucometers are susceptible to a wide range of errors, and only a few haemoglobin-measuring devices have accuracy approaching that of laboratory analysis. Activated coagulation time remains a useful but error-prone test for heparin effects. Thromboelastography and thromboelastometry offer insight into coagulation defects superior to conventional assays. Multi-function testers provide cardiac enzyme and lactate analysis that is becoming vital for intraoperative decision-making.Keywords: benefits; risks; shock; inotropes; vasopressor

Quality in point of care testing

Part of this document has been endorsed as a Position Statement on Point of Care testing (in-hospital setting) of the Italian Society of Laboratory Medicine (Società Italiana di Medicina di Laboratorio, SIMeL) and also refers to official documents and International standards to for generalities (ISO 15189/2003) and specific items (ISO 22870/2006). As such, this article is based on to professional standards, guidelines and peer reviews documents, and it is aimed to improve the pre-analytical, analytical and post-analytical phase of point of care testing (POCT), by providing insights into definitions, key aspects in developing a diagnostic system for POCT, benefits and risks of POCT and leading sources of errors

Cardiac biomarkers by point-of-care testing - back to the future?

The measurement of the cardiac troponins (cTn), cardiac troponin T (cTnT) and cardiac troponin I (cTnI) are integral to the management of patients with suspected acute coronary syndromes (ACS). Patients without clear electrocardiographic evidence of myocardial infarction require measurement of cTnT or cTnI. It therefore follows that a rapid turnaround time (TAT) combined with the immediacy of results return which is achieved by point-of-care testing (POCT) offers a substantial clinical benefit. Rapid results return plus immediate decision-making should translate into improved patient flow and improved therapeutic decision-making. The development of high sensitivity troponin assays offer significant clinical advantages. Diagnostic algorithms have been devised utilising very low cut-offs at first presentation and rapid sequential measurements based on admission and 3 h sampling, most recently with admission and 1 h sampling. Such troponin algorithms would be even more ideally suited to point-of-care testing as the TAT achieved by the diagnostic laboratory of typically 60 min corresponds to the sampling interval required by the clinician using the algorithm. However, the limits of detection and analytical imprecision required to utilise these algorithms is not yet met by any easy-to-use POCT systems

Enzyme Biosensors for Point-of-Care Testing

Biosensors are devices that integrate a variety of technologies, containing biology, electronics, chemistry, physics, medicine, informatics, and correlated technology. Biosensors act as transducer with a biorecognition element and transform a biochemical reaction on the transducer surface directly into a measurable signal. The biosensors have the advantages of rapid analysis, low cost, and high precision, which are widely used in many fields, such as medical care, disease diagnosis, food detection, environmental monitoring, and fermentation industry. The enzyme biosensors show excellent application value owing to the development of fixed technology and the characteristics of specific identification, which can be combined with point-of-care testing (POCT) technology. POCT technology is attracting more and more attention as a very effective method of clinic detection. We outline the recent advances of biosensors in this chapter, focusing on the principle and classification of enzyme biosensor, immobilization method of biorecognition layers, and fabrication of amperometric biosensors, as well as the applications of POCT. A summary of glucose biosensor development and integrated setups is included. The latest applications of enzyme biosensors in diagnostic applications focusing on POCT of biomarkers in real samples were described

Point of Care Testing: Best Practice Toolkit for Improving Access to Point of Care Testing in Mobile Medicine

Practice Problem: Healthcare for persons experiencing homelessness (PEH) is a complex issue. Chronic and communicable diseases are disproportionately represented within this population. Healthcare spending is 2.5 times more costly in comparison to those who have not experienced homelessness. Although mobile health clinics aim to reduce the concerns with access to care, they do not eliminate barriers if the appropriate tests are not immediately available. PICO: In the homeless population treated in mobile medicine (P), what is the effect of point of care testing (I) on turnaround time (O) compared with outside laboratory testing (C)? Evidence: Critical analysis of the literature revealed that point of care testing (POCT) is equivalent to or better at improving test results from baseline, improving medication adherence, and cost effectiveness. In PEH, this can significantly reduce the average days to treatment. Intervention: Using the CDC’s Program Evaluation Framework, three established mobile health clinics were evaluated to determine if the mobile environment was an appropriate setting to support POCT tools. Ultimately, it was determined that there was a need for an environment-specific toolkit to support additional POCT tools in mobile healthcare. Outcome: A POCT in mobile medicine toolkit was created to support implementation of additional tools, which can provide rapid and convenient access to testing, results and treatment in a population known to have difficulty accessing traditional healthcare services. Conclusion: This toolkit is designed to improve the multi-layered and complex issue of healthcare for the intended population. This is driven by the need to enhance the quality of care, patient outcomes, and operational efficiency of mobile healthcare

Point-of-care testing for disasters: needs assessment, strategic planning, and future design.

Objective evidence-based national surveys serve as a first step in identifying suitable point-of-care device designs, effective test clusters, and environmental operating conditions. Preliminary survey results show the need for point-of-care testing (POCT) devices using test clusters that specifically detect pathogens found in disaster scenarios. Hurricane Katrina, the tsunami in southeast Asia, and the current influenza pandemic (H1N1, "swine flu") vividly illustrate lack of national and global preparedness. Gap analysis of current POCT devices versus survey results reveals how POCT needs can be fulfilled. Future thinking will help avoid the worst consequences of disasters on the horizon, such as extensively drug-resistant tuberculosis and pandemic influenzas. A global effort must be made to improve POC technologies to rapidly diagnose and treat patients to improve triaging, on-site decision making, and, ultimately, economic and medical outcomes

Point of care testing for C-reactive protein

Copyright © 2006 Royal Australian College of General Practitioners Copyright to Australian Family Physician. Reproduced with permission. Permission to reproduce must be sought from the publisher, The Royal Australian College of General Practitioners.BACKGROUND: New approaches are needed to reduce antibiotic usage in respiratory tract infections in general practice without compromising patient safety. Point of care tests for C-reactive protein (CRP) are now being used for this purpose in some European countries. OBJECTIVE: Current knowledge about the CRP response in respiratory tract infections is presented, as well as the usefulness of applying the test when sinusitis and pneumonia may be suspected. DISCUSSION: A promising ability of the test in ruling in or out severe infection has been demonstrated in clinical studies. There are still controversies about the use of the CRP test in respiratory tract infections, however clinical research supports its use for some conditions, and therefore introduction into Australian general practice should be considered. Further evaluation of its utility is needed.H. Melbye and N. Stock

Point of Care Testing Error in the ICU

Point-of-care testing (POCT) first arose in the 1970s, as self-calibrating blood gas measurement machines moved from the central lab to the ICU. Quality control factors, then as now, dictated operation by trained personnel. Sources of error reported in the literature are varied. We discuss POCT error in the context of two clinical cases

Point‐of‐Care Testing in Sickle Cell Disease

Sickle cell disease is one of the most common inherited blood disorders. Universal screening and central laboratory diagnostics have improved early identification of affected individuals and helped to reduce childhood mortality in high‐resource countries. Additional methods of centralized diagnostics have also been developed in some low resource areas in partnership with private companies, local governments and academic US‐based institutions. However, these techniques require expansive infrastructure and government partnership for success. Thus, many individuals living in low‐resource settings are often not diagnosed until late childhood when they present with clinical symptoms. In addition, confirmation of disease in affected individuals in the urgent care setting remains limited in both high‐ and low‐resource areas due to the use of batched testing methods. All of the current diagnostic methods rely on advanced laboratory systems and are often prohibitively expensive and time‐consuming. To address this need and improve the capacity for timely diagnosis, novel methods for point‐of‐care testing for sickle cell disease are currently in process