The laboratory-clinical interface: point-of-care testing

Using geographic rescue time contours, point-of-care strategies, and spatial care paths to prepare island communities for global warming, rising oceans, and weather disasters

OBJECTIVES

To perform geographic contour analysis of sea and land ambulance rescue times in an archipelago subject to super typhoons; to design point-of-care testing strategies for medical emergencies and weather disasters made more intense by global warming and rising oceans; and to assess needs for prehospital testing on spatial care paths that accelerate decision making, increase efficiency, improve outcomes, and enhance standards of care in island nations.

METHODS

We performed needs assessments, inspected healthcare facilities, and collected ambulance rescue times from professionals in the Bantayan Archipelago, Philippines. We mapped sea/land ambulance rescue routes and time contours. To reveal gaps, we statistically compared the fastest and slowest patient rescue times from islands/islets and barangays to the District Hospital on Bantayan Island. We developed spatial care paths (the fastest routes to care) for acute myocardial infarction, community care, and infectious diseases. We generated a compendium of prehospital diagnostic testing and integrated outcomes evidence, diagnostic needs, and public health goals to recommend point-of-care strategies that build geographic health resilience.

RESULTS

We observed limited access to COVID-19 assays, absence of blood gas/pH testing for critical care support, and spatial gaps in land and airborne rescues that worsened during inclement weather and sea swells. Mean paired differences (slowest-fastest) in ambulance rescue times to the District Hospital for both islands and barangays were significant (P < 0.0001). Spatial care path analysis showed where point-of-care cardiac troponin testing should be implemented for expedited care of acute myocardial infarction. Geospatial strengths comprised distributed primary care that can be facilitated by point-of-care testing, logical interisland transfers for which decision making and triage could be accelerated with onboard diagnostics, and healthcare networks amenable to medical advances in prehospital testing that accelerate treatment.

CONCLUSIONS

Point-of-care testing should be positioned upstream close to homes and island populations that have prolonged rescue time contours. Geospatially optimized point-of-need diagnostics and distributed prehospital testing have high potential to improve outcomes. These improvements will potentially decrease disparities in mortality among archipelago versus urban dwellers, help improve island public health, and enhance resilience for increasingly adverse and frequent climate change weather disasters that impact vulnerable coastal areas. [350 words].

Point-of-care testing performed by healthcare professionals outside the hospital setting: consensus based recommendations from the IFCC Committee on Point-of-Care Testing (IFCC C-POCT)

The International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) Committee on Point-of-Care Testing (C-POCT) supports the use of point-of-care testing (POCT) outside of the hospital setting performed by healthcare professionals without formal laboratory education because of its numerous benefits. However, these benefits are associated with risks that must be managed, to ensure the provision of reliable test results and minimize harm to the patient. Healthcare professionals, local regulatory bodies, accredited laboratories as well as manufacturers should actively be engaged in education, oversight and advice to ensure that the healthcare professional selects the appropriate equipment and is able to analyze, troubleshoot and correctly interpret the point-of-care (POC) test results.

A Comprehensive Study: Traditional and Cutting-Edge Analytical Techniques for the Biomarker Based Detection of the Micronutrients & POC Sensing Directions for Next-Generation Diagnostic

Micronutrient deficiency is wide spread and highly affects morbidity, mortality, and well-being of human beings. Micronutrient deficiency gradually manifests into diseases, which effects pathophysiology directly or indirectly. There is an imprecision in the diagnosis of micronutrient deficiency because of two causes; the selection of the standard biomarker and the diagnostic technique used. In appropriate diagnosis could increase the severity of the disorder. Instead of a single a combination of biomarkers can give more stringent results for micronutrient testing. Several traditional analytical techniques are used for diagnosis but HPLC, ELISA & LCMS/MS are most sensitive and reliable methods used by CLSIA-certified labs. However, these techniques require well-equipped, centralized laboratory facilities. The diagnostic era moves toward the Point of Care Testing (POCT), a boon in emerging diagnostics, breaking all paradigms of traditional analytical techniques. POCT led us toward the development of biosensors, which encompasses many techniques like paper-based sensors, microfluidic chip, wearable devices, and smartphone-assisted diagnostics, which become more popular diagnostic tools. This outlook summarizes the micronutrients like vitamins A, B5, B6, B7, B9, B12 C, D, and E and Minerals like iron, calcium, zinc, magnesium, and sodium; along with its biomarkers, analytical techniques, and point of care innovation in micronutrients.

Every treasured drop! Blood transfusion requirements in very preterm neonates after implementation of blood conservation strategies: an observational analytical study

BACKGROUND

Certain morbidities are inevitable in preterm infants; the challenge lies in minimizing them. Anemia of prematurity is multifactorial. Therapy largely depends on adult red blood cell transfusions (RBCT); which inherently, are not without problems. Most literature in this respect are retrospective or evaluate individual stratagems to reduce RBCT.

METHODS

This observational analytical study was planned to compare need for RBCT, before and after institution of blood conservation strategies (BCS). All those ≤30 weeks gestation at birth during two-time epochs were included (Before BCS: retrospective; After BCS: prospective). BCS constituted of delayed cord clamping (DCC), strict sampling indications, micro-sampling with point-of-care testing (MS-POCT) and adherence to RBCT thresholds.

RESULTS

Of 45 enrolled neonates in each group, proportion of those requiring even 1 RBCT was significantly reduced after BCS [51.1% vs. 26.7%, p = 0.02, OR 0.35, 95%CI (0.14, 0.84)]. Calculated cumulative blood volume losses (35.3 ml vs. 21.9 ml) and loss per kilogram birth weight (35.3 ml/kg vs. 20.12 ml/kg) were significantly lower after BCS (p = 0.0036). Need for &gt;1 RBCT, mean lowest Hb, mean maximum-hemoglobin drop, need for arterial lines were reduced. Adherence to RBCT thresholds were acceptably good in both time epochs. However, the compliance to DCC was low in both groups, identifying one area of focus with scope for massive improvement.

CONCLUSIONS

Need for RBCT transfusions largely attributable to reduced blood losses for lab analysis were reduced after BCS. Installation of in-house MS-POCT seemed to be the pivotal factor. Units that care for very preterm infants must make attempts to procure MS-POCT equipment.

Comparison of hemoglobin values obtained by arterial blood gas analysis versus laboratory method during major head-and-neck surgeries

Background:

Accuracy of hemoglobin (Hb) measured by arterial blood gas (ABG) analyzer is considered inferior to laboratory (lab) measurements as it could overestimate Hb levels.

Aim of the Study:

The study aims to compare Hb measured using ABG versus conventional lab method at the time of major blood loss and in the preoperative and immediate postoperative periods.

Settings and Design:

It was a prospective, nonrandomized observational study conducted in a tertiary care center.

Materials and Methods:

The study was conducted in 24 patients undergoing major head-and-neck surgeries. Simultaneous blood samples were sent for Hb measurement by ABG analysis and lab method at induction of anesthesia, when intraoperative blood loss exceeded maximum allowable blood loss, and in the immediate postoperative period.

Statistical Analysis Used:

Chi-square test, independent sample's t-test, and paired t-test were used for statistical analysis.

Results:

Mean Hb values obtained by both techniques were significantly different at all time points. Hb obtained by ABG analysis was significantly higher than lab value preoperatively (12.78 ± 2.51 vs. 12.05 ± 2.2, P = 0.038), at maximum blood loss (11.00 ± 2.57 vs. 9.87 ± 2.06, P = 0.006), and in the immediate postoperative period (11.96 ± 2.00 vs. 10.96 ± 2.24 P < 0.001). ABG Hb values were found to be approximately 1 g.dL⁻¹ greater than lab values.

Conclusion:

Hb measured by ABG analysis was significantly higher than that measured by lab method at the time of major blood loss, preoperatively, and at the immediate postoperative period in patients undergoing major head-and-neck surgeries, with a good correlation of values obtained by both the techniques.

Prehospital emergency medical technicians can perform ultrasonography and blood analysis in prehospital evaluation of patients with chronic obstructive pulmonary disease: a feasibility study

INTRODUCTION

Crowding of the emergency departments is an increasing problem. Many patients with an exacerbation of chronic obstructive pulmonary disease (COPD) are often treated in the emergency departments for a very short period before discharged to their homes. It is possible that this treatment could take place in the patients' homes with sufficient diagnostics supporting the treatment. In an effort to keep the diagnostics and treatment of some of these patients in their homes and thus to reduce the patient load at the emergency departments, we implemented a prehospital treat-and-release strategy based on ultrasonography and blood testing performed by emergency medical technicians (EMT) or paramedics (PM) in patients with acute exacerbation of COPD.

METHOD

EMTs and PMs were enrolled in a six-hour educational program covering ultrasonography of the lungs and point of care blood tests. During the seasonal peak of COPD exacerbations (October 2018 - May 2019) all patients who were treated by the ambulance crews for respiratory insufficiency were screened in the ambulances. If the patient had uncomplicated COPD not requiring immediate transport to the hospital, ultrasonographic examination of the lungs, measurements of C-reactive protein and venous blood gases analyses were performed. The response to the initial treatment and the results obtained were discussed via telemedical consultation with a prehospital anaesthesiologist who then decided to either release the patient at the scene or to have the patient transported to the hospital. The primary outcome was strategy feasibility.

RESULTS

We included 100 EMTs and PMs in the study. During the study period, 771 patients with respiratory insufficiency were screened. Uncomplicated COPD was rare as only 41patients were treated according to the treat-and-release strategy. Twenty of these patients (49%) were released at the scene. In further ten patients, technical problems were encountered hindering release at the scene.

CONCLUSION

In a few selected patients with suspected acute exacerbations of COPD, it was technically and organisationally feasible for EMTs and PMs to perform prehospital POCT-ultrasound and laboratory testing and release the patients following treatment. None of the patients released at the scene requested a secondary ambulance within the first 48 h following the intervention.

Geospatial Spread of Antimicrobial Resistance, Bacterial and Fungal Threats to Coronavirus Infectious Disease 2019 (COVID-19) Survival, and Point-of-Care Solutions

CONTEXT.—

Point-of-care testing (POCT) is inherently spatial, that is, performed where needed, and intrinsically temporal, because it accelerates decision-making. POCT efficiency and effectiveness have the potential to facilitate antimicrobial resistance (AMR) detection, decrease risks of coinfections for critically ill patients with coronavirus infectious disease 2019 (COVID-19), and improve the cost-effectiveness of health care.

OBJECTIVES.—

To assess AMR identification by using POCT, describe the United States AMR Diagnostic Challenge, and improve global standards of care for infectious diseases.

DATA SOURCES.—

PubMed, World Wide Web, and other sources were searched for papers focusing on AMR and POCT. EndNote X9.1 (Clarivate Analytics) consolidated abstracts, URLs, and PDFs representing approximately 500 articles were assessed for relevance. Panelist insights at Tri•Con 2020 in San Francisco and finalist POC technologies competing for a US $20,000,000 AMR prize are summarized.

CONCLUSIONS.—

Coinfections represent high risks for COVID-19 patients. POCT potentially will help target specific pathogens, refine choices for antimicrobial drugs, and prevent excess morbidity and mortality. POC assays that identify patterns of pathogen resistance can help tell us how infected individuals spread AMR, where geospatial hotspots are located, when delays cause death, and how to deploy preventative resources. Shared AMR data "clouds" could help reduce critical care burden during pandemics and optimize therapeutic options, similar to use of antibiograms in individual hospitals. Multidisciplinary health care personnel should learn the principles and practice of POCT, so they can meet needs with rapid diagnostic testing. The stakes are high. Antimicrobial resistance is projected to cause millions of deaths annually and cumulative financial loses in the trillions by 2050.

Volatile organic compounds as disease predictors in newborn infants: a systematic review

Volatile organic compounds (VOC) detected in human breath, urine, stool, sweat, saliva, and blood result from metabolic processes in the body during health or disease. Using sophisticated measurement systems, small amounts of these compounds can be detected in the above bodily fluids. Multiple studies in adults and children have shown the potential of these compounds to differentiate between healthy individuals and patients by detecting profiles of compounds in non-invasively collected samples. However, the detection of biomarkers in VOCs from neonates is particularly attractive due to the non-invasive nature of its approach, and its ability to track disease progress by longitudinal sampling. In this work we have reviewed the literature on the use of VOCs in neonates and identified areas for future work.

Point-of-Care Testing Practices, Failure Modes, and Risk-Mitigation Strategies in Emergency Medical Services Programs in the Canadian Province of Alberta

CONTEXT.—

Emergency medical services (EMS) programs have been using point-of-care testing (POCT) for more than 20 years. However, only a handful of reports have been published in all of that time on POCT practices in field settings.

OBJECTIVE.—

To provide an overview of POCT practices and failure modes in 3 of Alberta's EMS programs, and to propose risk-mitigation strategies for reducing or eliminating these failure modes.

DESIGN.—

Details about POCT practices, failure modes, and risk-mitigation strategies were gathered through (1) conversations with personnel, (2) in-person tours of EMS bases, (3) accompaniment of EMS personnel on missions, (4) internet searches for publicly available information, and (5) a review of laboratory documents.

RESULTS.—

Practices were most standardized and robust in the community paramedicine program (single service provider, full laboratory oversight), and least standardized and robust in the air ambulance program (4 service providers, limited laboratory oversight). Common failure modes across all 3 programs included device inoperability due to cold weather, analytical validation procedures that failed to consider the unique challenges of EMS settings, and a lack of real-time electronic transmission of results into the health care record.

CONCLUSIONS.—

A provincial framework for POCT in EMS programs is desirable. Such a framework should include appropriate funding models, laboratory oversight of POCT, and relevant expertise on POCT in EMS settings. The framework should also incorporate specific guidance on quality standards that are needed to address the unique challenges of performing POCT in field settings.

Geospatial Hotspots Need Point-of-Care Strategies to Stop Highly Infectious Outbreaks

CONTEXT.—

Point-of-care testing (POCT), diagnostic testing at or near the site of patient care, is inherently spatial, that is, performed at points of need, and also intrinsically temporal, because it produces fast actionable results. Outbreaks generate geospatial "hotspots." POC strategies help control hotspots, detect spread, and speed treatment of highly infectious diseases.

OBJECTIVES.—

To stop outbreaks, accelerate detection, facilitate emergency response for epidemics, mobilize public health practitioners, enhance community resilience, and improve crisis standards of care.

DATA SOURCES.—

PubMed, World-Wide Web, newsprint, and others were searched until Coronavirus infectious disease-19 was declared a pandemic, the United States, a national emergency, and Europe, the epicenter. Coverage comprised interviews in Asia, email to/from Wuhan, papers, articles, chapters, documents, maps, flowcharts, schematics, and geospatial-associated concepts. EndNote X9.1 (Clarivate Analytics) consolidated literature as abstracts, ULRs, and PDFs, recovering 136 hotspot articles. More than 500 geospatial science articles were assessed for relevance to POCT.

CONCLUSIONS.—

POCT can interrupt spirals of dysfunction and delay by enhancing disease detection, decision-making, contagion containment, and safe spacing, thereby softening outbreak surges and diminishing risk before human, economic, and cultural losses mount. POCT results identify where infected individuals spread Coronavirus infectious disease-19, when delays cause death, and how to deploy resources. Results in national cloud databases help optimize outbreak control, mitigation, emergency response, and community resilience. The Coronavirus infectious disease-19 pandemic demonstrates unequivocally that governments must support POCT and multidisciplinary healthcare personnel must learn its principles, then adopt POC geospatial strategies, so that onsite diagnostic testing can ramp up to meet needs in times of crisis.

Geospatial Science and Point-of-Care Testing: Creating Solutions for Population Access, Emergencies, Outbreaks, and Disasters

Objectives: (a) To understand how to integrate geospatial concepts when implementing point-of-care testing (POCT); (b) to facilitate emergency, outbreak, and disaster preparedness and emergency management in healthcare small-world networks; (c) to enhance community resilience by using POCT in tandem with geographic information systems (GISs) and other geospatial tools; and (d) to advance crisis standards of care at points of need, adaptable and scalable for public health practice in limited-resource countries and other global settings.

Content: Visual logistics help integrate and synthesize POCT and geospatial concepts. The resulting geospatial solutions presented here comprise: (1) small-world networks and regional topography; (2) space-time transformation, hubs, and asset mapping; (3) spatial and geospatial care paths™; (4) GIS-POCT; (5) isolation laboratories, diagnostics isolators, and mobile laboratories for highly infectious diseases; (6) alternate care facilities; (7) roaming POCT—airborne, ambulances, space, and wearables; (8) connected and wireless POCT outside hospitals; (9) unmanned aerial vehicles; (10) geospatial practice—demographic care unit resource scoring, geographic risk assessment, and national POCT policy and guidelines; (11) the hybrid laboratory; and (12) point-of-careology.

Value: Small-world networks and their connectivity facilitate efficient and effective placement of POCT for optimal response, rescue, diagnosis, and treatment. Spatial care paths™ speed transport from primary encounters to referral centers bypassing topographic bottlenecks, process gaps, and time-consuming interruptions. Regional GISs position POCT close to where patients live to facilitate rapid triage, decrease therapeutic turnaround time, and conserve economic resources. Geospatial care paths™ encompass demographic and population access features. Timeliness creates value during acute illness, complex crises, and unexpected disasters. Isolation laboratories equipped with POCT help stop outbreaks and safely support critically ill patients with highly infectious diseases. POCT-enabled spatial grids can map sentinel cases and establish geographic limits of epidemics for ring vaccination.

Impact: Geospatial solutions generate inherently optimal and logical placement of POCT conceptually, physically, and temporally as a means to improve crisis response and spatial resilience. If public health professionals, geospatial scientists, and POCT specialists join forces, new collaborative teamwork can create faster response and higher impact during disasters, complex crises, outbreaks, and epidemics, as well as more efficient primary, urgent, and emergency community care.

In-Transit Electroextraction of Small-Molecule Pharmaceuticals from Blood

An electrokinetic platform was developed for extracting small-molecule pharmaceuticals from a dried blood spot. Through the exclusion of liquid reagents and use of low field strength (6 V cm^-1 ), the electroextraction of a drug from a dried blood spot, deposited on a polymer inclusion membrane (PIM), could be realised while in transit in the mail. In transit sample preparation provides a potential solution to in situ sample degradation and may accelerate the workflow upon arrival of a patient sample at the analytical facility. The electroextraction method was enabled through our discovery of the use of 15-20 μm thin PIMs as electrophoretic separation medium in absence of liquid reagents. Here, a PIM consisting of cellulose triacetate as polymer base, 2-nitrophenyl octyl ether as plasticizer and 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide as carrier was used. The PIM, was packaged with two 12 V batteries to supply the separation voltage. A blood spot containing berberine chloride was deposited and dried before the applying the separation potential, allowing for the electroextraction while the packaged device was shipped in internal mail. Upon arrival in the analytical laboratory, the PIM was analysed using a fluorescence microscope with photon multiplier tube, quantifying the berberine extracted away from the sample matrix. This platform represents a new opportunity for processing clinical samples during transport to the laboratory, saving time and manual handling to accelerate the time to result.

Can point-of-care testing shorten hospitalization length of stay? An exploratory investigation of infectious agents using regression modelling

This retrospective study investigates the potential benefits from the introduction of point-of-care tests for rapid diagnosis of infectious diseases. We analysed a sample of 441 hospitalized patients who had received a final diagnosis related to 18 pathogenic agents. These pathogens were mostly detected by standard tests but were also detectable by point-of-care testing. The length of hospital stay was partitioned into pre- and post-laboratory diagnosis stages. Regression analysis and elementary queueing theory were applied to estimate the impact of quick diagnosis on the mean length of stay and the utilization of healthcare resources. The analysis suggests that eliminating the pre-diagnosis times through point-of-care testing could shorten the mean length of hospital stay for infectious diseases by up to 34 per cent and result in an equal reduction in bed occupancy and other resources. Regression and other more sophisticated models can aid the financing decision-making of pilot point-of-care laboratories in healthcare systems.

Point-of-care lactate and creatinine analysis for sick obstetric patients at Queen Elizabeth Central Hospital in Blantyre, Malawi: A feasibility study

BACKGROUND

To achieve good outcomes in critically ill obstetric patients, it is necessary to identify organ dysfunction rapidly so that life-saving interventions can be appropriately commenced. However, timely access to clinical chemistry results is problematic, even in referral institutions, in the sub-Saharan African region. Reliable point-of-care tests licensed for clinical use are now available for lactate and creatinine.

AIM

We aimed to assess whether implementation of point-of-care testing for lactate and creatinine is feasible in the obstetric unit at the Queen Elizabeth Central Hospital (QECH) in Blantyre, Malawi, by obtaining the opinions of clinical staff on the use of these tests in practice.

METHODS

During a two-month evaluation period nurse-midwives, medical interns, clinical officers, registrars, and consultants were given the opportunity to use StatStrip® and StatSensor® (Nova Biomedical, Waltham, USA) devices, for lactate and creatinine estimation, as part of their routine clinical practice in the obstetric unit. They were subsequently asked to complete a short questionnaire.

RESULTS

Thirty-seven questionnaires were returned by participants: 22 from nurse-midwives and the remainder from clinicians. The mean satisfaction score for the devices was 7.6/10 amongst clinicians and 8.0/10 amongst nurse-midwives. The majority of participants stated that the obstetric high dependency unit (HDU) was the most suitable location for the devices. For lactate, 31 participants strongly agreed that testing should be continued and 24 strongly agreed that it would influence patient management. For creatinine, 29 strongly agreed that testing should be continued and 28 strongly agreed that it would influence their patient management. Twenty participants strongly agreed that they trust point-of-care devices.

CONCLUSIONS

Point-of-care clinical chemistry testing was feasible, practical, and well received by staff, and was considered to have a useful role to play in the clinical care of sick obstetric patients at this referral centre.

Analytical Protein Microarrays: Advancements Towards Clinical Applications

Protein microarrays represent a powerful technology with the potential to serve as tools for the detection of a broad range of analytes in numerous applications such as diagnostics, drug development, food safety, and environmental monitoring. Key features of analytical protein microarrays include high throughput and relatively low costs due to minimal reagent consumption, multiplexing, fast kinetics and hence measurements, and the possibility of functional integration. So far, especially fundamental studies in molecular and cell biology have been conducted using protein microarrays, while the potential for clinical, notably point-of-care applications is not yet fully utilized. The question arises what features have to be implemented and what improvements have to be made in order to fully exploit the technology. In the past we have identified various obstacles that have to be overcome in order to promote protein microarray technology in the diagnostic field. Issues that need significant improvement to make the technology more attractive for the diagnostic market are for instance: too low sensitivity and deficiency in reproducibility, inadequate analysis time, lack of high-quality antibodies and validated reagents, lack of automation and portable instruments, and cost of instruments necessary for chip production and read-out. The scope of the paper at hand is to review approaches to solve these problems.

Point-of-Care Versus Central Laboratory Measurements of Hemoglobin, Hematocrit, Glucose, Bicarbonate and Electrolytes: A Prospective Observational Study in Critically Ill Patients

Introduction

Rapid detection of abnormal biological values using point-of-care (POC) testing allows clinicians to promptly initiate therapy; however, there are concerns regarding the reliability of POC measurements. We investigated the agreement between the latest generation blood gas analyzer and central laboratory measurements of electrolytes, bicarbonate, hemoglobin, hematocrit, and glucose.

Methods

314 paired samples were collected prospectively from 51 critically ill patients. All samples were drawn simultaneously in the morning from an arterial line. BD Vacutainer tubes were analyzed in the central laboratory using Beckman Coulter analyzers (AU 5800 and DxH 800). BD Preset 3 ml heparinized-syringes were analyzed immediately in the ICU using the POC Siemens RAPIDPoint 500 blood gas system. We used CLIA proficiency testing criteria to define acceptable analytical performance and interchangeability.

Results

Biases, limits of agreement (±1.96 SD) and coefficients of correlation were respectively: 1.3 (-2.2 to 4.8 mmol/L, r = 0.936) for sodium; 0.2 (-0.2 to 0.6 mmol/L, r = 0.944) for potassium; -0.9 (-3.7 to 2 mmol/L, r = 0.967) for chloride; 0.8 (-1.9 to 3.4 mmol/L, r = 0.968) for bicarbonate; -11 (-30 to 9 mg/dL, r = 0.972) for glucose; -0.8 (-1.4 to -0.2 g/dL, r = 0.985) for hemoglobin; and -1.1 (-2.9 to 0.7%, r = 0.981) for hematocrit. All differences were below CLIA cut-off values, except for hemoglobin.

Conclusions

Compared to central Laboratory analyzers, the POC Siemens RAPIDPoint 500 blood gas system satisfied the CLIA criteria of interchangeability for all tested parameters, except for hemoglobin. These results are warranted for our own procedures and devices. Bearing these restrictions, we recommend clinicians to initiate an appropriate therapy based on POC testing without awaiting a control measurement.

Preanalytical conditions of point-of-care testing in the intensive care unit are decisive for analysis reliability

Background

Point-of-care testing (POCT) systems enable a wide range of tests to be rapidly performed at the bedside and have attracted increasing interest in the intensive care unit (ICU). However, previous studies comparing the concordance of POCT with central laboratory testing have reported divergent findings. Most reported studies on POCT reliability have focused on analyzer performance rather than the preanalytical phase. The aim of this study was to assess the reliability of results provided by point-of-care analyzers according to the organization of the care units and the preanalytical process.

Methods

In three adult critical care units, 491 paired blood samples were analyzed for hemoglobin, potassium, and sodium concentrations by blood gas analyzers (identical reference) and the central laboratory. The clinical significance of agreement was assessed using Bland–Altman plots. A quality improvement program was then implemented to improve the preanalytical POCT process for one ICU where there was poor agreement. A second comparison was performed on 278 paired blood samples in this unit.

Results

Biases were clinically nonsignificant for potassium and sodium concentrations for all tested critical care units, relative to the reference method. However, biases [limits of agreements] for hemoglobin analyses were clearly affected by the preanalytical process: −3 [−6; 1] g/L in the operating room, −5 [−28; 17] g/L in a 10-bed ICU, and −19 [−64; 27] g/L in a 37-bed ICU. The quality approach was implemented in the 37-bed ICU and led to corrective actions that: (1) reduced the time for the POCT preanalytical phase; (2) implemented a checklist to validate the preanalytical conditions; (3) used technical innovations. The improvement of the preanalytical process resulted in a substantial decrease of the bias for hemoglobin concentration measurements: −3 [−10; 5] g/L in the 37-bed ICU.

Conclusion

We clearly demonstrate that an identical analyzer can provide results of varying quality depending on the local constraints of the ICUs. We demonstrate that quality management focused on the preanalytical process and performed by the partners involved in the POCT can overcome these issues.

Reduction of Laboratory Utilization in the Intensive Care Unit

Objective:

In our academic intensive care unit (ICU), there is excess ordering of routine laboratory tests. This is partially due to a lack of transparency of laboratory-processing costs and to the admission order plans that favor daily laboratory test orders. We hypothesized that a program that involves physician and staff education and alters the current ICU order sets will lead to a sustained decrease in routine laboratory test ordering.

Design:

Prospective cohort study.

Setting:

Academic closed medical ICU (MICU).

Patients:

All patients admitted to the MICU.

Methods:

We consistently educated residents, faculty, and staff about laboratory test costs. We removed the daily laboratory test option from the admission order sets and asked residents to order needed laboratory test results every day. We only allowed the G3+I-STAT (arterial blood gas only) cartridges in the MICU in hopes of decreasing duplicative laboratory test results. We added laboratory review to the daily rounding checklist.

Measurement and Main Results:

Total number of laboratory tests per patient-day decreased from 39.43 to an average of 26.74 ( P <.001) over a 9-month period. The number of iSTAT laboratory tests per patient-day decreased from 7.37 to an average of 1.16 ( P < .001) over the same time period. The number of iSTAT/central laboratory processing duplicative laboratory tests per patient-day decreased from 0.17 to an average of 0.01 ( P < .001). The percentage of patients who have daily laboratory test orders decreased from 100% to an average of 11.94% ( P <. 001). US$123 436 in direct savings and US$258 035 dollars in indirect savings could be achieved with these trends. Intensive care unit morbidity and mortality were not impacted.

Conclusion:

A simple technique of resident, nursing, and ancillary staff education, combined with alterations in order sets using electronic medical records, can lead to a sustained reduction in laboratory test utilization over time and to significant cost savings without affecting patient safety.

Recent advances in point-of-care testing for natriuretic peptides: potential impact on heart failure diagnosis and management

Heart failure is a leading cause of morbidity and mortality worldwide. The presenting symptoms of heart failure are often nonspecific. The diagnosis of heart failure has traditionally relied heavily upon clinical exam findings, which are often subjective and have low sensitivity. Efficient and rapid diagnosis of heart failure in the emergency room setting can reduce health care costs, hospital admission and ER visits, and improve patient care. Natriuretic peptides are objective biomarkers that can help with diagnosis, prognosis and management of heart failure. The most extensively studied and clinically utilized natriuretic peptides include brain natriuretic peptide (BNP) and N-terminal proBNP (NT-proBNP). Point-of-care testing in the emergency room setting can result in faster triage times. Point-of-care testing can also be utilized in the outpatient setting for real-time management of patients with heart failure.

Molecular detection and point-of-care testing in Ebola virus disease and other threats: a new global public health framework to stop outbreaks

Ultrahigh sensitivity and specificity assays that detect Ebola virus disease or other highly contagious and deadly diseases quickly and successfully upstream in Spatial Care Paths™ can stop outbreaks from escalating into devastating epidemics ravaging communities locally and countries globally. Even had the WHO and CDC responded more quickly and not misjudged the dissemination of Ebola in West Africa and other world regions, mobile rapid diagnostics were, and still are, not readily available for immediate and definitive diagnosis, a stunning strategic flaw that needs correcting worldwide. This article strategizes point-of-care testing for diagnosis, triage, monitoring, recovery and stopping outbreaks in the USA and other countries; reviews Ebola molecular diagnostics, summarizes USA FDA emergency use authorizations and documents why they should not be stop-gaps; and reduces community risk from internal and external infectious disease threats by enabling public health at points of need.

Implementation of POCT in the diabetic clinic in a large hospital

AIM

Point-of-care testing (POCT) is gaining renewed interest, especially in resource-limiting primary health care, due to rise in prevalence of communicable and non-communicable diseases hence POCT needscontinuous appraisal.

METHODS

Random glucose and glycated haemoglobin (HbA1c) were measured in 104 diabetic patients using standard laboratory multichannel analyzer 917. The utility of venous blood compared to capillary blood in measuring HbA1c was evaluated in a subset of 20 patients using a POCT device, DCA Vantage. Lastly, the POCT was validated against the laboratory multichannel analyser 917, in measurement of HbA1c in a second subset of 46 patients.

RESULTS

Random blood glucose levels and HbA1c levels moderately correlated (r2 = 0.56; p < 0.0001). Random glucose tests showed that 41% of the patients had poor glycaemic control while HbA1c showed 74%. Venous and capillary blood in HbA1c showed strong correlation (r2 = 0.89440; p < 0.001. There was also strong correlation (r = 0.9802; p < 0.0001) in HbA1c measured using the DCA Vantage and the standard laboratory analyser, Multichannel Analyser 917.

CONCLUSION

Venous or capillary blood can be used in POCT for HbA1c. POCT is ideal for monitoring glucose control and management of diabetes in resource-limited countries such as South Africa.

Bedside evaluation of cardiac markers

Accurate and rapid diagnostic tests can help identify high-risk patients with ACS among those presenting to the emergency department with chest pain. Such tests can also differentiate low-risk patients with chest pain who are suitable for early emergency department discharge. In this article, Drs Amsterdam and Deedwania elucidate the varieties of ACS, their pathophysiology, and the methods used for diagnosis. The authors also explore the potential of point-of-care testing for cardiac injury markers in the timely and accurate identification of ACS.

Agreement between whole blood and plasma sodium measurements in profound hyponatremia

OBJECTIVES

We compared two different methods of whole blood sodium measurement to plasma sodium measurement using samples in the profoundly hyponatremic range (Na < 120 mmol/L).

DESIGN AND METHODS

Whole blood pools with a range of low sodium values were generated using combinations and dilutions of pooled electrolyte-balanced lithium heparin samples submitted for arterial blood gas analysis. Each pool was analyzed five times on a Radiometer 827 blood gas analyzer and iSTAT analyzer. Pools were centrifuged to produce plasma, which was analyzed five times on a Roche Cobas c501 chemistry analyzer. An additional 40 fresh (analyzed on day of collection) excess lithium heparin arterial blood gas samples from 36 patients were analyzed on the Radiometer 827, iSTAT, and Cobas c501 as described above. The setting was a tertiary referral center. Blood samples were collected from a combination of patients in the intensive care unit, operating theaters and emergency room.

RESULTS

All methods demonstrated excellent precision, even in the profoundly hyponatremic measurement range (Na < 120 mmol/L using a plasma reference method). However, agreement between the methods varied with the degree of hyponatremia. In the profoundly hyponatremic range, Radiometer whole blood sodium values were nearly identical to plasma reference sodium, while iSTAT whole blood sodium showed a consistent positive bias relative to plasma sodium in this range.

CONCLUSION

If whole blood direct sodium measurements are compared with plasma sodium in profoundly hyponatremic patients consideration should be given to the use of Radiometer blood gas analyzers over iSTAT since the latter shows a positive bias relative to a plasma comparative method.

Feasibility of HIV point-of-care tests for resource-limited settings: challenges and solutions

Improved access to anti-retroviral therapy increases the need for affordable monitoring using assays such as CD4 and/or viral load in resource-limited settings. Barriers to accessing treatment, high rates of loss to initiation and poor retention in care are prompting the need to find alternatives to conventional centralized laboratory testing in certain countries. Strong advocacy has led to a rapidly expanding repertoire of point-of-care tests for HIV. point-of-care testing is not without its challenges: poor regulatory control, lack of guidelines, absence of quality monitoring and lack of industry standards for connectivity, to name a few. The management of HIV increasingly requires a multidisciplinary testing approach involving hematology, chemistry, and tests associated with the management of non-communicable diseases, thus added expertise is needed. This is further complicated by additional human resource requirements and the need for continuous training, a sustainable supply chain, and reimbursement strategies. It is clear that to ensure appropriate national implementation either in a tiered laboratory model or a total decentralized model, clear country-specific assessments need to be conducted.

Surgical management in treatment of Jehovah's witness in trauma surgery in Indian subcontinent

The Jehovah's Witness religion is a Christian movement, founded in the US in the 1870s, with 7 million followers worldwide with only 0.002% in India. There is minimal to complete absence of awareness about the existence of this community in our society. Astonishing is that fact that among medical professionals, there is almost no awareness about this unique population, regarding the fact that they completely refuse of blood transfusion even if it leads to their death. This is integral to their faith. Besides legal and ethical issues in treating these group of patients, the biggest challenge exist even in the western world is their management in trauma scenario where few options exist. We have discussed the issues and recommendations in management in trauma scenario in our Indian subcontinent.

Design and Realization of Integrated Management System for Data Interoperability between Point-of-Care Testing Equipment and Hospital Information System

Objectives

The purpose of this study was to design an integrated data management system based on the POCT1-A2, LIS2-A, LIS2-A2, and HL7 standard to ensure data interoperability between mobile equipment, such as point-of-care testing equipment and the existing hospital data system, its efficiency was also evaluated.

Methods

The method of this study was intended to design and realize a data management system which would provide a solution for the problems that occur when point-of-care testing equipment is introduced to existing hospital data, after classifying such problems into connectivity, integration, and interoperability. This study also checked if the data management system plays a sufficient role as a bridge between the point-of-care testing equipment and the hospital information system through connection persistence and reliability testing, as well as data integration and interoperability testing.

Results

In comparison with the existing system, the data management system facilitated integration by improving the result receiving time, improving the collection rate, and by enabling the integration of disparate types of data into a single system. And it was found out that we can solve the problems related to connectivity, integration and interoperability through generating the message in standardized types.

Conclusions

It is expected that the proposed data management system, which is designed to improve the integration point-of-care testing equipment with existing systems, will establish a solid foundation on which better medical service may be provided by hospitals by improving the quality of patient service.

Evaluation of a modified lateral flow immunoassay for detection of high-sensitivity cardiac troponin I and myoglobin

We prospectively evaluated the use of lateral flow immunoassay (LFIA) test modified with nanoparticles for combined detection of high-sensitivity cardiac troponin I (hs-cTnI) and myoglobin with the aim of excluding acute myocardial infarction (AMI). Specimens from 173 patients with symptoms suggestive of AMI were collected to measure hs-cTnI and myoglobin using an electrochemiluminescence immunoassay (ECLI) and the LFIA test modified with nanoparticles, and a comparison was performed between the modified method and a commercial LFIA test for detection of the two proteins. The accuracy of the modified LFIA test was also evaluated. Consistent agreement was observed in the quantitative comparison of 173 clinical samples using the modified LFIA and ECLI, and the modified method was more sensitive than the commercial LFIA test. The accuracy of the modified LFIA was <12% for both hs-cTnI and myoglobin. Thus, the new approach has great potential to improve LFIAs test, demonstrating its usefulness for simple screening applications and for sensitivity and quantitative immunoassays for diagnosis ofAMI.

Use of a blood gas analyzer and a laboratory autoanalyzer in routine practice to measure electrolytes in intensive care unit patients

Background

Electrolyte values are measured in most critically ill intensive care unit (ICU) patients using both an arterial blood gas analyzer (ABG) and a central laboratory auto-analyzer (AA). The aim of the present study was to investigate whether electrolyte levels assessed using an ABG and an AA were equivalent; data on sodium and potassium ion concentrations were examined.

Methods

We retrospectively studied patients hospitalized in the ICU between July and August 2011. Of 1,105 test samples, we identified 84 instances of simultaneous sampling of arterial and venous blood, where both Na⁺ and K⁺ levels were measured using a pHOx Stat Profile Plus L blood gas analyzer (Nova Biomedical, Waltham MA, USA) and a Roche Modular P autoanalyzer (Roche Diagnostics, Mannheim, Germany). Statistical measures employed to compare the data included Spearman's correlation coefficients, paired Student’s t-tests, Deming regression analysis, and Bland-Altman plots.

Results

The mean sodium concentration was 138.1 mmol/L (SD 10.2 mmol/L) using the ABG and 143.0 mmol/L (SD 10.5) using the AA (p < 0.001). The mean potassium level was 3.5 mmol/L (SD 0.9 mmol/L) using the ABG and 3.7 mmol/L (SD 1.0 mmol/L) using the AA (p < 0.001). The extent of inter-analyzer agreement was unacceptable for both K⁺ and Na⁺, with biases of 0.150-0.352 and −0.97-10.05 respectively; the associated correlation coefficients were 0.88 and 0.90.

Conclusions

We conclude that the ABG and AA do not yield equivalent Na⁺ and K⁺ data. Concordance between ABG and AA should be established prior to introduction of new ABG systems.

CMOS cell sensors for point-of-care diagnostics

The burden of health-care related services in a global era with continuously increasing population and inefficient dissipation of the resources requires effective solutions. From this perspective, point-of-care diagnostics is a demanded field in clinics. It is also necessary both for prompt diagnosis and for providing health services evenly throughout the population, including the rural districts. The requirements can only be fulfilled by technologies whose productivity has already been proven, such as complementary metal-oxide-semiconductors (CMOS). CMOS-based products can enable clinical tests in a fast, simple, safe, and reliable manner, with improved sensitivities. Portability due to diminished sensor dimensions and compactness of the test set-ups, along with low sample and power consumption, is another vital feature. CMOS-based sensors for cell studies have the potential to become essential counterparts of point-of-care diagnostics technologies. Hence, this review attempts to inform on the sensors fabricated with CMOS technology for point-of-care diagnostic studies, with a focus on CMOS image sensors and capacitance sensors for cell studies.

Evaluation of the Xpert Flu test and comparison with in-house real-time RT-PCR assays for detection of influenza virus from 2008 to 2011 in Marseille, France

Rapid documentation of respiratory specimens can have an impact on the management of patients and their relatives in terms of preventive and curative measures. We compared the results of the Xpert(®) Flu assay (Cepheid) with three real-time RT-PCR assays using 127 nasopharyngeal samples, of which 75 were positive for influenza A (with 52 identified as A/H1N1-2009) and 52 were positive for influenza B. The Xpert(®) Flu assay presented a quasi-absence of non-interpretable tests, and showed sensitivity and specificity of 100% and 100% for Flu A, 98.4% and 100% for A/H1N1-2009, and 80.7% and 100% for Flu B.

Evaluation of two devices for point-of-care testing of haemoglobin in neonatal pigs

In veterinary medicine, point-of-care testing (POCT) techniques have become popular, since they provide immediate results and only small amounts of blood are needed. However, their accuracy is controversial. Pigs are often used for research purposes and accurate measurement of haemoglobin (Hb) is important during invasive procedures. The aim of this study was to evaluate two different Hb POCT devices in neonatal pigs. A prospective study with 57 pigs of 3-6 weeks of age, weighing 4.1-6.2 kg (median 5.1 kg) was performed. Fifty-seven blood samples were analysed for Hb using a conductivity-based and a photometrical POCT device and compared with a photometrical reference method. Statistical analysis was performed with Bland-Altman analysis, Spearman correlation and Passing-Bablok regression analysis. Hb values ranged from 32 to 108 g/L (median 80 g/L) using the reference method. The bias of the photometrical method (HemoCue(®)) to the reference method was -1 g/L, with limits of agreement (LOA) of -7 to 6 g/L. The conductivity-based method (i-STAT(®)) had a bias of -15 g/L with LOA from -24 to -6 g/L. There was a significant association between protein values and the bias of i-STAT versus CellDyn (r(2) = 0.27, P < 0.05) but not with the bias of HemoCue versus CellDyn (r(2) = 0.001, P = 0.79). The lower the protein values were, the lower the Hb values were measured by the i-STAT. The conductivity-based measurement of Hb constantly underestimated Hb values, whereas the photometrical method demonstrated a better accuracy and is therefore more reliable for on-site measurement of Hb in pigs.

Revolutionizing clinical microbiology laboratory organization in hospitals with in situ point-of-care

BACKGROUND

Clinical microbiology may direct decisions regarding hospitalization, isolation and anti-infective therapy, but it is not effective at the time of early care. Point-of-care (POC) tests have been developed for this purpose.

METHODS AND FINDINGS

One pilot POC-lab was located close to the core laboratory and emergency ward to test the proof of concept. A second POC-lab was located inside the emergency ward of a distant hospital without a microbiology laboratory. Twenty-three molecular and immuno-detection tests, which were technically undemanding, were progressively implemented, with results obtained in less than four hours. From 2008 to 2010, 51,179 tests yielded 6,244 diagnoses. The second POC-lab detected contagious pathogens in 982 patients who benefited from targeted isolation measures, including those undertaken during the influenza outbreak. POC tests prevented unnecessary treatment of patients with non-streptococcal tonsillitis (n = 1,844) and pregnant women negative for Streptococcus agalactiae carriage (n = 763). The cerebrospinal fluid culture remained sterile in 50% of the 49 patients with bacterial meningitis, therefore antibiotic treatment was guided by the molecular tests performed in the POC-labs. With regard to enterovirus meningitis, the mean length-of-stay of infected patients over 15 years old significantly decreased from 2008 to 2010 compared with 2005 when the POC was not in place (1.43±1.09 versus 2.91±2.31 days; p = 0.0009). Altogether, patients who received POC tests were immediately discharged nearly thrice as often as patients who underwent a conventional diagnostic procedure.

CONCLUSIONS

The on-site POC-lab met physicians' needs and influenced the management of 8% of the patients that presented to emergency wards. This strategy might represent a major evolution of decision-making regarding the management of infectious diseases and patient care.

From cleanroom to desktop: emerging micro-nanofabrication technology for biomedical applications

This review is motivated by the growing demand for low-cost, easy-to-use, compact-size yet powerful micro-nanofabrication technology to address emerging challenges of fundamental biology and translational medicine in regular laboratory settings. Recent advancements in the field benefit considerably from rapidly expanding material selections, ranging from inorganics to organics and from nanoparticles to self-assembled molecules. Meanwhile a great number of novel methodologies, employing off-the-shelf consumer electronics, intriguing interfacial phenomena, bottom-up self-assembly principles, etc., have been implemented to transit micro-nanofabrication from a cleanroom environment to a desktop setup. Furthermore, the latest application of micro-nanofabrication to emerging biomedical research will be presented in detail, which includes point-of-care diagnostics, on-chip cell culture as well as bio-manipulation. While significant progresses have been made in the rapidly growing field, both apparent and unrevealed roadblocks will need to be addressed in the future. We conclude this review by offering our perspectives on the current technical challenges and future research opportunities.

Standardization, Harmonization, and Realization

Point-of-care testing is useful when caring for patients in hospital settings and in emergency and disaster situations. However, point-of-care professional practice lacks components, such as standardization, harmonization, and consistency, which would substantially improve patient care if implemented. Therefore, we propose adoption of whole-blood standards, harmonization among testing methods, and tighter quality control constraints. Granting these 3 wishes will improve quality at the point of care and ultimately will improve diagnoses, treatment decisions, and patient outcomes.