Point-of-care Glucometer Research Articles

Performance of point‐of‐care glucose testing for the diagnosis of gestational diabetes in South Africa

AbstractObjectiveLack of accessibility to oral glucose tolerance tests (OGTTs) in South Africa means many pregnant women go without testing for gestational diabetes mellitus (GDM). This study evaluated point‐of‐care (POC) glucometers against the laboratory‐based glucose method in pregnant women.MethodsThis was a cross‐sectional study on pregnant women attending the prenatal clinic in Johannesburg who were recommended for the OGTT. OGTTs were conducted as per International Association of Diabetes and Pregnancy Study Groups (IADPSG) guidelines. Women who consented to the study donated both venous and capillary blood for laboratory‐based and POC glucose measurements using seven POC glucometers: I‐STAT, Xpress, LDX, VivaChek‐Ino, Accu‐Chek Active, StatStrip, and Codefree. By assessing sensitivity, specificity, and area under the receiver operating characteristic curve (AUC) and comparing Bland–Altman plots, the diagnostic accuracy of each glucose meter was compared with the reference method, the laboratory‐based glucose method.ResultsData were analyzed for 1076 pregnant women. Based on OGTT testing, 83 women had GDM (7.7%). Overall, the POC glucometers performed poorly, with sensitivity ranging from 17.6% to 87.18% and specificity ranging between 62.7% and 99.8%. The AUC ranged from 0.59 to 0.79. All POC glucometers showed moderate to poor reliability. Laboratory‐based fasting plasma glucose (FPG) surpassed the POC glucometers in sensitivity, specificity, and AUC, with values of 94.0%, 100%, and 0.98, respectively.ConclusionWe demonstrated that laboratory‐based FPG has the potential to be used as a diagnostic test for GDM and that the POC glucometers cannot replace OGTT laboratory‐based measurements.

Evaluating the Bias of Two Point-of-Care Glucometers for Calves and Ewes: Awareness for Ruminant Practitioners

(1) Background: Multiple point-of-care (POC) glucometers are in use in veterinary medicine, but few are compared to each other. This leaves the potential for clinicians to be unaware of the effect of bias when comparing results from different POC glucometers. (2) Methods: Samples from healthy calves and ewes were simultaneously compared with two POC veterinary glucometers, the Precision Xtra and the AlphaTrak2, under both the “canine” and “feline” settings. The results of each sample were statistically analyzed with linear regression and Bland–Altman analysis. (3) Results: 170 samples from healthy calves and 108 samples from healthy ewes were available for comparison. Calves: The AT2 consistently overestimated blood glucose concentrations when compared to the PX device with the calves. Correlationt with the PX was r = 0.8496 (canine setting) and r = 0.8861 (feline setting). Both the canine and feline settings demonstrated a consistent bias (41.11 and 33.64 mg/dL, respectively). Ewes: The AT2 consistently overestimated blood glucose concentrations when compared to the PX device with the ewes. Correlation with the PX was R = 0.4710 (canine setting) and R = 0.7269 (feline setting). Both the canine and feline settings demonstrated a consistent bias (21.23 and 14.54 mg/dL, respectively). (4) Clinicians should be aware of the potential for consistent bias when evaluating calf and sheep blood glucose concentrations as the AT2 device, at both settings, overestimated blood glucose compared to the previously validated PX. This reliability appears to change when the values are farther from the normal ranges, which should be considered when making clinical decisions based on data from these devices.

Accuracy of point-of-care capillary blood sugar measurements in critically ill patients: An observational study.

Accurately monitoring blood glucose levels is vital for critically ill individuals. Point-of-care (POC) glucose meters are commonly used in local intensive care units (ICUs). This study aimed to assess the precision of POC glucose meter readings in critically ill individuals with specific evaluation in patients with and without shock against the reference standard of venous blood glucose measurements. An observational study was done on adult patients admitted in the ICU at a teaching institution. Capillary blood samples were collected from the patient's fingertip using lancet device with aseptic measures. The sample was analyzed using the GlucoCare Sense Glucometer (RMD Mediaids Limited, Taiwan). At the same time, 2 ml of blood was drawn from the patient's peripheral veins and analyzed by glucose oxidase-peroxidase method as reference. POC glucose measurements averaged 140 ± 20.23 mg/dl, while laboratory values were recorded as 116.10 ± 17.13 mg/dl. The difference between the two methods was 24.34 ± 12.01 mg/dl. A strong correlation (r = 0.805) was found between capillary and laboratory blood glucose levels, indicating a significant association (P < 0.0001). Twenty-two (44%) patients were in shock during the study. The mean difference between laboratory and POC blood glucose levels was higher in patients with circulatory shock (36.82 ± 4.84 mg/dl) than those without shock (14.61 ± 4.49 mg/dl), P < 0.05. POC glucose meters may lead to underdetection of hypoglycemia in critically ill patients, as their values are higher than laboratory values. Moreover, the results showed that POC glucometers are inaccurate for monitoring glucose in hypotensive patients in shock. Standard venous glucose monitoring methods may be more appropriate for these patients.

Reliability and accuracy of bedside capillary blood glucose measurement by glucometers compared to venous blood glucose in critically ill patients: A facility based cross-sectional study

BackgroundThe traditional reference standard, venous blood glucose requires venipuncture and laboratories usually return the test results after 60 minutes. Our aim was to determine the agreement accuracy of glucose (capillary) levels obtained by POC glucometers with glucose (venous) values by standard laboratory method (glucose-oxidase) and to assess whether and to what extent the glucometers perform uniformly well across the entire range of blood glucose values. MethodsWe compared the diagnostic accuracy of two- point of care glucometers with laboratory venous glucose, the reference standard using Bland- Altman plots and Clark error grid method to analyse the results. ResultsThis study included a total of 110 patients (38[34%] women; mean age 52.1 years (SD, 17.3); range 14 to 85 years. Fourteen patients (12%) were known to have diabetes. The mean glucose value (glucometer 1) was 152.9 mg/dL (SD 83.1); range= 48 to 501 mg/dL; that by glucometer 2 was 152.2 mg/dL (SD 76.2); range= 30 to 458 mg/dL and by the laboratory was 148.6 mg/dL (SD 81.5); range= 52 to 480 mg/dL. Of the 110 subjects, 2(2%) had blood glucose below 70 mg/dL; 85(77%) between 70 and 180 mg/ dL and 23(21%) had blood glucose exceeding 180 mg/dL. The Bland- Altman plot showed a bias of 4 mg% (95%CI -9.8 to +1.1); and the limits of agreement were -63 and +54 mg%. The area under the receiver operating characteristic curve for the two glucometers was 0.92 and 0.93 respectively. ConclusionsPoint of care glucose, measured by glucometers was in agreement with the venous glucose estimation. Both glucometers were equally accurate and performed uniformly well across the wide range of blood glucose values.

1065-P: Utilizing a Novel Telemedicine Clinic for Managing Patients with Type 2 Diabetes

Objective: To examine whether a new Diabetes Telemedicine (DT) clinic can lead to improved glycemic control compared to standard of care (SoC). Design: Pilot RCT of patients with type 2 diabetes (T2D) randomized to DT clinic or SoC. DT intervention comprised of continuous glucose monitoring, “connected” insulin pens/caps, telecommunication systems (i.e. video conferencing, online messaging and telephone) and promoting physical activity (PA) by providing brief counseling and exercise physiologist consultation. SoC was managed using point of care glucometer, traditional insulin pens, in-person visits and provider counseling on PA. Primary outcome was change in HbA1c. Secondary outcomes were time in range (TIR) 70-180 mg/dl, time above range (TAR)&amp;gt;180 mg/dl and time below range (TBR)&amp;lt; 70 mg/dl. Patients also completed senior fitness test, assessed by Hedge’s g effect size. Results: A total of 18 patients (17 male) have been recruited, 11 patients were black and 7 white, all non-Hispanic. 14 completed 90 days in the trial. Non statistically significant differences were seen. DT had an 1.6% (mean SE 0.60) HbA1c reduction vs 0.4 (0.69) in SoC [difference -1.2% (0.92), p=0.19]. TIR 70-180 mg/dl increased 8.5% (13.6) (DT) vs 4.4% (15.8) (SoC) [difference +4.1% (20.8), p=0.84]. DT had a decrease in TAR&amp;gt;180 mg/dl of 8.7% (13.7) compared to 4.4% (15.8) in SoC [difference -4.3% (21.0), p=0.85] and TBR&amp;lt;70 mg/dl 0.16% (0.60) (DT) vs 0.13% (0.69) (SoC) [difference of 0.03% (0.92), p=0.97]. DT had improved aerobic capacity (6-minute walk test 402±62 to 418±69m, g=0.53) and strength in the lower- (30-second chair stand 9.0±2.6 to 11.5±2.6 stands, g=0.91) and upper-body (30-second weighted arm curl 17.4±5.3 to 21.0±6.3 curls, g=0.72). SoC had no meaningful changes in aerobic capacity or lower/upper-body strength (g=-0.05 to 0.18). Conclusion: Patients with T2D managed with DT had a non-statistically significant improvement of glucose control and improved physical fitness performance compared to patients in SoC. Disclosure F.Sotomayor: None. I.Spanakis: Research Support; Dexcom, Inc. C.Gothong: None. R.Hernandez: None. G.I.Ash: None. W.H.Scott: None. L.Pinault: None. F.Gomez-peralta: Advisory Panel; Abbott Diabetes, Insulcloud S.L., Speaker's Bureau; A. Menarini Diagnostics, Boehringer Ingelheim and Eli Lilly Alliance, Lilly Diabetes, Novartis, Novo Nordisk. L.G.Singh: None. J.D.Sorkin: None.

Evaluation of the Agreement Between 2 Point-Of-Care Glucometers and a Laboratory Automated Analyzer in North American Raptors.

Blood glucose abnormalities are commonly observed in veterinary medicine. Point-of-care (POC) glucometers provide rapid results, are inexpensive, and require very small sample volumes to measure blood glucose concentrations. Although POC glucometers are used frequently in dogs and cats, there have been few studies evaluating POC glucometers in avian species, none of which include raptors. This study evaluated the agreement between a veterinary POC glucometer, a human POC glucometer, and a benchtop laboratory automated analyzer (auto analyzer) using both plasma and whole blood samples from 50 free-ranging raptors admitted to the University of Illinois Wildlife Medical Clinic (Urbana, IL, USA). The veterinary POC glucometer, when used with plasma and whole blood, and the human POC glucometer, when used with whole blood, were in poor agreement with the laboratory auto analyzer. The human POC glucometer, when used with plasma, was in greatest agreement with the laboratory auto analyzer, meeting the US Food and Drug Administration's accuracy guidelines for "over-the-counter" POC glucometers for use in humans. Based on these results, the use of the Contour Next EZ with plasma samples is the only POC recommended for use in raptors. Further research should focus on assessing the clinical utility of blood glucose measurements when treating various disease processes in raptors and the prognostic value of blood glucose measurements when assessing critically ill raptors.

Effect of hematocrit, galactose and ascorbic acid on the blood glucose readings of three point-of-care glucometers

Glucometers are commonly used in a variety of healthcare settings and use in critically ill patients should not be assumed without appropriate tool validation. The study objective was to evaluate the accuracy of three point-of-care glucometers (POCGs) to assess glucose concentration in human blood sample. The POCGs tested included three different instruments and utilized three factors (hematocrit [Hct], galactose and ascorbic acid) in glucose measurements to determine the glucometers’ accuracy and compared to the reference laboratory biochemical analyzer (Cobs 8000, Roche, Basal, Switzerland). In this study, the Nova StatStrip glucometer showed no significant variation compared to the laboratory method at high glucose level with various Hct%. ACCU-Chek Inform II overestimated the glucose results at Hct 22% and underestimated at Hct 62%. The Freestyle glucometer showed lower glucose levels compared to the Cobas 8000 at Hct 62%. The ACCU-Check showed significant increase of blood glucose with low Hct% levels when compared to the laboratory method. The Freestyle showed a decreased level of glucose with high Hct 62% interference compared to the Cobas 8000. Galactose interference 100 and 200 mg/dL dramatically affected the accuracy of ACCU-Chek Inform II. Nevertheless, among all three POCGs in this study, the Nova StatStrip showed the most reliable and stable results for glucose level in the presence of interference. Especially, those in critical care units, whereas the Freestyle Precision Pro and ACCU-Chek Inform II were insufficiently accurate for critically ill patients.

LBSUN214 Accuracy Of A Continuous Glucose Monitor In The Intensive Care Unit

Abstract Studies have shown that hyper/hypoglycemia and glycemic variation are associated with adverse outcomes in critically ill patients. Currently, frequent blood point-of-care (POC) glucose measurements from an arterial or capillary sample is the only technology available to minimize glycemic excursions in the ICU. Continuous glucose monitoring (CGM) is becoming the standard of care for outpatient diabetes care and has shown improved glycemic control in the non-ICU inpatient setting. The Dexcom G6 sensor (G6) is the first CGM device approved by Health Canada for outpatient diabetes management without the need for calibration, but it has not yet been approved for inpatient use. We collected data from 23 adults who were on an insulin infusion in a medical-surgical ICU in Vancouver, British Columbia to evaluate the accuracy of uncalibrated CGM in the ICU. A blinded G6 was attached to the patient's arm and collected glucose measurements every five minutes without calibration. Nursing staff continued POC arterial glucose measurements using the AccuChek Inform II machine per standard of care. Excluding four outliers (with mean absolute relative difference (MARD) ≥ 25%), the overall MARD was 13.24% (SE 0.43) over 649 matched CGM and arterial glucose values. A Clarke Error Grid demonstrated 99.1% of CGM measurements within zones A and B. The MARD using three-point rolling averages of CGM measurements in five-minute intervals was 13.49% (SE 0.68). There were 573 matched pairs between glucose ranges of 3.9-13.9 mmol/L with two pairs &amp;lt;3.9 and 74 pairs &amp;gt;13.9 mmol/L. Eleven patients had renal replacement therapy and twelve had vasopressor use. There was no significant difference in MARD with renal replacement or across glycemic ranges ≥3.9. The MARD for patients with vasopressors was lower than for patients without (13% vs 13.55%, p&amp;lt;0. 01), a finding of doubtful clinical relevance. There is no expert agreement yet about the acceptable accuracy for CGM use in hospital. Our overall MARD meets the 2013 Critical Care expert consensus recommendations for MARD &amp;lt;14%. The FDA guidance on standard of accuracy for conventional POC glucometers require 98% of values within 15% for BG ≥ 75mg/dL. Our data showed 65.18% of values were within 15%. Previous studies using CGM in the ICU, even those using G6, all used calibration. The majority were non-blinded, and none met FDA criteria for inpatient use. Our study is the first uncalibrated and blinded study that was able to demonstrate acceptable accuracy in a large sample size. Since CGM accuracy may be affected by various factors, our comprehensive data can potentially identify specific interferences and quantify a calibration or correction criteria to improve CGM accuracy in critically ill patients. Overall, our results show that CGM shows strong potential to be an accurate, resource-efficient, and intuitive alternative to POC glucose monitoring to meet glycemic targets in the ICU. Presentation: Sunday, June 12, 2022 12:30 p.m. - 2:30 p.m.

Validation of a flash glucose monitoring system in outpatient diabetic cats.

BackgroundInterstitial glucose (IG) concentration measurement using a flash glucose monitoring system (FGMS) is a noninvasive, affordable, and informative method to regulate patients with diabetes mellitus (DM) but has not been fully validated in outpatient cats with DM.ObjectivesTo further validate the FreeStyle Libre FGMS in outpatient diabetic cats.AnimalsEight client‐owned cats with DM.MethodsProspective observational validation study. Tissue glue was used to attach the sensor to the cat. Lin's concordance correlation coefficient (ρ c) was used to compare IG concentrations measured by the FGMS to blood glucose concentrations measured using an automated biochemistry analyzer (ABA) and point‐of‐care glucometer (POCG).ResultsData from 15 sensor placements in 8 cats were analyzed. Paired IG and ABA glucose concentrations (139 samples) had excellent correlation (ρ c = 0.96) as did IG and POCG glucose concentrations (142 samples, ρ c = 0.92). Sensor failure or displacement were recorded for 12/15 (80%) sensor placements. Median time of sensor activity was 7 days (range, 2‐13 days).Conclusions and Clinical ImportanceIn outpatient cats with DM, the FGMS‐measured IG concentration correlated well with ABA‐measured blood glucose concentration, but a high rate of sensor failures was observed.

A comparative study of glycaemic variability using four different Point-of-Care Testing (POCT) devices

Background: Blood glucose measurement is a way of monitoring changes in glycaemia. Different point-of-care testing (POCT) glucose meters are on the market and hence there is an increase in variability of the results given by these meters. This study sought to measure the glycaemic variability using four different point-of-care glucose meters Methods: Four point of care glucometers namely; Accu-chek performer nano, OneTouch select plus flex, OneTouch Ultra 2 and Easy Check were used test blood samples from a total of 100 patients visiting the collection point of the Tamale Teaching Hospital Laboratory. A chemistry analyzer (Mindray BS 240 fully automated) was used as the reference method. Results: The median (interquartile range), Bland Altman Plot and Regression Equation were used to assess the agreement between the various meters and the reference method. The OneTouch Select plus had the least bias (-0.85) and the the OneTouch Ultra 2 had the highest bias (1.49). The OneTouch select had the best limits of agreement (-2.51 – 0.82) and the OneTouch Ultra 2 had the widest limits of agreement (-1.91 – 4.89) when compared to the reference method. Conclusion: OneTouch Select plus had the best agreement with the reference method and the OneTouch Ultra 2 had the least agreement with the reference method. Blood glucose meters should be used for the monitoring of blood glucose however, it should not be used as a diagnostic tool. Annals of Medical Laboratory Science (2021) 1(2), 1 - 8 Keywords: glucometer, point-of-care, blood glucose, glycaemia

Evaluation of a continuous glucose monitoring system in neonatal foals.

BackgroundMonitoring blood glucose concentrations is common in critically ill neonatal foals, especially septic foals and those receiving naso‐esophageal feedings or IV parenteral nutrition. Glucose typically is measured using a point‐of‐care (POC) glucometer but requires repeated restraint and blood collections, which may cause irritation at venipuncture sites and increased demands on nursing staff. Continuous glucose monitoring systems (CGMS) may provide an accurate alternative for monitoring blood glucose concentration.ObjectivesTo determine the correlation and accuracy of a CGMS to monitor neonatal foals' blood glucose concentrations as compared to a POC glucometer and laboratory chemistry analysis (CHEM).AnimalsSamples from 4 healthy and 4 ill neonatal foals.MethodsA CGMS was placed on each foal, and glucose measurements acquired from this device were compared to simultaneous measurements of blood glucose concentration using a POC glucometer and CHEM.ResultsTwo‐hundred matched glucose measurements were collected from 8 neonatal foals. The mean bias (95% limits of agreement) between CGMS and CHEM, CGMS and POC glucometer, and POC glucometer and CHEM was 3.97 mg/dL (−32.5 to 40.4), 18.2 mg/dL (−28.8 to 65.2), and 22.18 mg/dL (−9.3 to 53.67), respectively. The Pearson's correlation coefficient (r) was significantly correlated among all devices: GCMS and CHEM (r = 0.81), CGMS and POC glucometer (r = 0.77) and POC glucometer‐CHEM (r = 0.92).Conclusions and Clinical ImportanceWithin the blood glucose concentration ranges in this study (78‐212 mg/dL), CGMS measurements were significantly correlated with CHEM, suggesting that it is an acceptable method to provide meaningful, immediate, and continuous glucose concentration measurements in neonatal foals while eliminating the need for repeated restraint and blood collection.

Knowledge of Validation Status of Point-of-care Glucometers among Veterinarians and Veterinary Technologists in Nigeria

Point-of-care glucometers (PCGs) have of recent almost replaced the conventional laboratory methods of blood glucose determination in animals. This study evaluated the level of awareness and knowledge about the use of handheld PCGs among veterinarians and veterinary technologists. Respondents to a structured questionnaire included academic staff and laboratory technologists from veterinary schools and public and private veterinarians across Nigeria. Design of the questions progressed from whether one had ever used a PCG before or not, how they knew about the PCG, the brands used, for what purposes and on which animals. Results showed that out of 209 respondents, 75 (36%) had used PCGs. Of this number, 37 (49.33%) used PCGs for research purposes, while 36 and 6.67% had used the PCGs for diagnosis of glucose disorders in animals and for both research and diagnostic purposes, respectively. The distribution of respondents that knew about the validation status of the PCGs used was 2.67%. As values generated by each PCG vary significantly in different species, there may be chances of reporting erroneous research conclusions as well as misdiagnosis of glucose disorders with consequent erroneous therapies in such species.&#x0D; Keywords: Point-of-care Glucometers, Validation status, Veterinarians.

Performance evaluation of three i-SENS glucometers using arterial blood samples compared with the YSI 2300 Glucose Analyzer.

BackgroundCapillary blood is the most commonly used sample for point‐of‐care (POC) glucometers. However, in critically ill patients, the glucose levels measured from capillary blood may not be reliable. Thus, we aimed to evaluate and compare the accuracy of glucose levels measured with POC glucometers and the YSI 2300 glucose analyzer using leftover arterial blood samples.MethodsIn total, 100 leftover heparinized arterial blood samples were used to evaluate the performance of three i‐SENS glucometers (BAROzen H Expert plus, CareSens PRO, and CareSens H Beat) and the ACCU‐CHEK® Inform II glucometer. The reference value was obtained using the YSI 2300 glucose analyzer. The results were analyzed based on International Organization for Standardization 15197:2013 guidelines.ResultsMore than 95% of results obtained using POC glucometers were within ±15 mg/dL of the reference value for glucose concentrations <100 mg/dL and within ±15% of the reference value for glucose concentrations ≥100 mg/dL. In the consensus error grid analysis, more than 99% of results were found to be within zones A and B. An excellent correlation was found between the values obtained using POC glucometers and the YSI 2300 glucose analyzer (R 2 > .99).ConclusionThe i‐SENS glucometers showed stable and accurate results when leftover arterial blood samples were used. Therefore, POC glucometers could be useful in critical care settings, such as intensive care units, where arterial samples are routinely used.

Comparison of a continuous indwelling glucometer with a point-of-care device in healthy adult horses

BackgroundBlood glucose is tightly regulated in horses; however, since hypoglycaemia and hyperglycaemia are associated with poor prognosis, close monitoring is warranted. This study aimed at evaluating a continuous indwelling glucometer...

Pre-/analytical factors affecting whole blood and plasma glucose concentrations in loggerhead sea turtles (Caretta caretta).

Blood glucose is vital for many physiological pathways and can be quantified by clinical chemistry analyzers and in-house point-of-care (POC) devices. Pre-analytical and analytical factors can influence blood glucose measurements. This project aimed to investigate pre-analytical factors on whole blood and plasma glucose measurements in loggerhead sea turtles (Caretta caretta) by evaluating the effects of storage (refrigeration) up to 48h after sampling and of packed cell volume (PCV) on whole blood glucose analysis by POC glucometer (time series n = 13); and by evaluating the effects of storage (room temperature and refrigeration) on plasma glucose concentrations using a dry slide chemistry analyzer (DCA) at various conditions: immediate processing and delayed plasma separation from erythrocytes at 24h and 48h (time series n = 14). The POC glucometer had overall strong agreement with the DCA (CCC = 0.76, r = 0.84, Cb = 0.90), but consistently overestimated glucose concentrations (mean difference: +0.4 mmol/L). The POC glucometer results decreased significantly over time, resulting in a substantial decline within the first 2h (0.41±0.47 mmol/L; 8±9%) that could potentially alter clinical decisions, thereby highlighting the need for immediate analysis using this method. The effects of PCV on glucose could not be assessed, as the statistical significance was associated with one outlier. Storage method significantly affected plasma glucose measurements using DCA, with room temperature samples resulting in rapid decreases of 3.57±0.89 mmol/L (77±9%) over the first 48h, while refrigerated samples provided consistent plasma glucose results over the same time period (decrease of 0.26±0.23 mmol/L; 6±5%). The results from this study provide new insights into optimal blood sample handling and processing for glucose analysis in sea turtles, show the suitability of the POC glucometer as a rapid diagnostic test, and confirm the reliability of plasma glucose measurements using refrigeration. These findings emphasize the need to consider pre-/analytical factors when interpreting blood glucose results from loggerhead sea turtles.

Comparison of glucose concentrations in serum, plasma, and blood measured by a point-of-care glucometer with serum glucose concentration measured by an automated biochemical analyzer for canine and feline blood samples.

To determine the correlation between glucose concentrations in serum, plasma, and blood measured by a point-of-care glucometer (POCG) and serum glucose concentration measured by an automated biochemical analyzer (ABA; gold standard). 152 canine and 111 feline blood samples. For each sample, the glucose concentration in serum, plasma, and blood was measured by a POCG and compared with the ABA-measured glucose concentration by means of the Lin concordance correlation coefficient. Results were summarized by species for all samples and subsets of samples with hyperglycemia (ABA-measured glucose concentration > 112 mg/dL for dogs and > 168 mg/dL for cats) and pronounced hyperglycemia (ABA-measured glucose concentration > 250 mg/dL for both species). The effect of PCV on correlations between POCG and ABA measurements was also assessed. Hyperglycemia and pronounced hyperglycemia were identified in 69 and 36 canine samples and 44 and 29 feline samples, respectively. The POCG-measured glucose concentrations in serum, plasma, and blood were strongly and positively correlated with the gold standard concentration. The PCV was positively associated with the correlation between the POCG-measured blood glucose concentration and the gold standard concentration but was not associated with the correlations between the POCG-measured glucose concentrations in serum and plasma and the gold standard concentration. Results indicated that POCG-measured glucose concentrations in serum, plasma, and blood were strongly correlated with the ABA-measured serum glucose concentration, even in hyperglycemic samples. Given the time and labor required to harvest serum or plasma from blood samples, we concluded that blood was the preferred sample type for use with this POCG.

Accuracy of Using a Point-of-Care Glucometer for Cerebrospinal Fluid Glucose Screening in Resource-Limited Countries

To explore the accuracy of using a point-of-care (POC) glucometer for cerebrospinal fluid (CSF) glucose screening. A cross-sectional study was conducted. A glucose analysis of CSF samples collected from infants <90 days with suspected meningitis was paired between tests by using a POC glucometer (POC-CSF glucose) and a laboratory glucose analysis (laboratory-CSF glucose). Accuracy and limits of agreement were compared, as well as the glucometer performance to detect a laboratory-CSF glucose level <45 and 60 mg/dL. Seventy-three CSF samples were analyzed. Subjects' mean gestational age was 32.2 (SD 4.0) weeks, the mean weight was 1947.7 (SD 814.5) g, and the median age was 8 (interquartile range: 2 to 19.5) days. POC-CSF glucose levels ranged from 26 to 126 mg/dL. The mean (±1.96 SD) difference between POC-CSF and laboratory-CSF glucose levels was -1.6 (interquartile range: -12.6 to 9.4) mg/dL. A POC-CSF glucose level <45 mg/dL has a sensitivity and negative predictive value (NPV) to detect a laboratory-CSF glucose level <45 mg/dL of 82% and 94%, respectively. For a laboratory-CSF glucose level <60 mg/dL, a POC glucose level <60 mg/dL provides a sensitivity and NPV of 96% and 90%, respectively, whereas sensitivity and NPV reach 100% at a POC glucose level <70 mg/dL. A POC glucometer for CSF glucose can detect a potential abnormal glucose level with an appropriate cutoff level. This may facilitate rapid decisions for empirical antibiotics in suspected meningitis, pending laboratory results in limited-resource settings, but requires robust validation in future studies before implementation.

Clinical Reliability of Point-of-Care Glucose Testing in Critically Ill Patients.

Point-of-care (POC) glucometers are commonly used in intensive care units (ICUs). The Centers for Medicare & Medicaid Services have called into question the accuracy of POC glucometers in critically ill patients. This study sought to identify specific characteristics within our facility's ICU patients that were associated with inaccuracies in POC glucose measurements. We conducted a prospective cohort study that compared POC capillary blood glucose samples with venous samples collected in our ICU. All nonpregnant patients >18 years old admitted to the ICU with orders for daily laboratory testing that included blood glucose were eligible for inclusion. A total of 46 patients were enrolled and 85 samples were collected. The mean difference between venous and POC samples was 5.23 mg/dL (95% CI, 3.16-7.3 mg/dL). Measurement inaccuracies would have altered treatment in 7/85 instances (8.2%). The only clinically significant inaccuracy found was the omission of 2 units of insulin in 1 hyperglycemic patient. Measurement inconsistencies generally underestimated low blood glucose values (2/2 instances) and overestimated high blood glucose values (4/5 instances). In our study, the mean difference between venous and POC glucose samples was small. Similarly, measurement inaccuracies that would have altered treatment were rare and only one instance was deemed clinically significant. We conclude that POC capillary glucose testing within our cohort and in similar critically ill patients is likely safe and effective.

Evaluation of a point‐of‐care blood glucose monitor in healthy goats

To assess agreement between a point-of-care glucometer (POCG) and a laboratory chemistry analyzer for blood glucose measurements in goats. Prospective study. University teaching hospital. Eighteen healthy adult goats. Whole blood samples were obtained via jugular venipuncture prior to premedication with xylazine and butorphanol (T0), following premedication (T20), and after 1 hour of inhalant anesthesia (T60). Each sample was tested with a POCG and a laboratory analyzer (HITA). Agreement was assessed using concordance correlation coefficients and calculation of bias and 95% limits of agreement. Mean blood glucose concentration at T0 was 3.9±0.6mmol/L (70±10mg/dL; POCG) and 2.9±0.4mmol/dL (53±8mg/dL; HITA). Glucose concentrations at T20 were 6.7±2.4mmol/L (121±43mg/dL) and 5.4±2.1mmol/L (97±37mg/dL) and at T60 were 5.7±1.7mmol/L (102±31mg/dL) and 4.7±1.3mmol/L (85±24mg/dL) when measured with the POCG and HITA, respectively. The POCG overestimated blood glucose compared to the HITA. The bias±SD was 1.08±0.53mmol/L (19.4±9.5mg/dL) (95% LOA 0.04 to 2.11mmol/L [0.7 to 38.0mg/dL]) and the concordance correlation coefficient was 0.82. After correcting the results of the POCG using a mixed-effects linear model, the bias was 0.0±0.38mmol/L (0.0±6.8mg/dL) (95% LOA ±0.74mmol/L [±13.4mg/dL]) and the concordance correlation coefficient was 0.98. The POCG overestimated blood glucose concentrations in goats, compared to the HITA, but when the POCG concentrations were corrected, the agreement was excellent.

Validity of bedside blood glucose measurement in critically ill patients with intensive insulin therapy.

Background and Aims:There have been variable results on the practice of tight glycemic control, and studies have demonstrated that point-of-care (POC) glucometers have variable accuracy. Glucometers must be accurate, and many variables can affect blood glucose levels. The purpose of this study was to determine the difference between blood glucose concentrations obtained from POC glucometers and laboratory results in critically ill patients with intensive insulin therapy.Materials and Methods:This was a descriptive study which enrolled 300 critically ill patients. Four samples of arterial blood were collected and analyzed at the bedside with the POC glucometer and also in the central laboratory to obtain the blood glucose level. To define the effect of various factors on this relation, we noted the levels of hemoglobin (Hb), PaO2, body temperature, bilirubin, history of drug usage, and sepsis.Results:There were not any significant differences between blood sugar levels using laboratory and glucometer methods of measurements. There was a good and significant correlation between glucose levels between two methods (r = 0.81, P < 0.001). Among evaluated factors (body temperature, bilirubin level, blood pressure, Hb level, PaO2, sepsis, and drugs) which added one by one in model, just drugs decreased the correlation more than others (r = 0.78).Conclusions:The results of POC glucometer differ from laboratory glucose concentrations, especially in critically ill patients with unstable hemodynamic status while receiving several drugs. This may raise the concern about using POC devices for tight glycemic control in critically ill patients. These results should be interpreted with caution because of the large variation of accuracy among different glucometer devices.