Blood glucose measurement in the intensive care unit: what is the best method?

Accuracy of the Dexcom G7 Continuous Glucose Monitoring Sensors in People with Diabetes Undergoing Hemodialysis (ALPHA-2 Study)

The accuracy of the latest generation Dexcom G7 sensors in individuals with diabetes undergoing hemodialysis has not previously been investigated. Participants with diabetes undergoing hemodialysis were recruited, with paired sensor glucose from Dexcom G7 recorded with plasma glucose analyzed in the laboratory, as well as the Freestyle Precision Pro glucometer and EKF Biosen C-Line analyzer. Ten adults (median age 64.0 [58.0-74.5] years) were recruited. Overall percentage (%) mean and median absolute relative differences were 10.4% and 8.5% for matched laboratory pairs, respectively (n = 720). Diabetes Technology Society error grid analysis showed 99.7%, 100%, and 99.9% of pairs within zones A and B for lab, glucometer, and EKF methods, respectively. This, the first Dexcom G7 accuracy study conducted in people on hemodialysis, demonstrates accuracy and safety when compared with lab reference readings. These data support the accessibility of continuous glucose monitoring (CGM) and hybrid closed-loop systems for people with diabetes on hemodialysis.

Factors Associated with Need for Intravenous Glucose Infusion for the Treatment of Early Neonatal Hypoglycemia in Late Preterm and Term Neonates

OBJECTIVE

The aim of this study was to determine which late-preterm (35-36 weeks' gestational age [GA]) and term neonates with early-onset hypoglycemia in the first 72 hours postnatal required a continuous glucose infusion to achieve and successfully maintain euglycemia.

STUDY DESIGN

This is a retrospective cohort study of late preterm and term neonates born in 2010-2014 and admitted to the Mother-Baby Unit at Parkland Hospital who had laboratory-proven blood glucose concentration < 40 mg/dL (2.2 mmol/L) during the first 72 hours of life. Among the subgroup needing intravenous (IV) glucose infusion, we analyzed which factors predicted a maximum glucose infusion rate (GIR) ≥ 10 mg/kg/min. The entire cohort was randomly divided into a derivation cohort (n = 1,288) and a validation cohort (n = 1,298).

RESULTS

In multivariate analysis, the need for IV glucose infusion was associated with small size for GA, low initial glucose concentration, early-onset infection, and other perinatal variables in both cohorts. A GIR ≥ 10 mg/kg/min was required in 14% of neonates with blood glucose value < 20 mg/dL during the first 3 hours of observation. The likelihood of a GIR ≥ 10 mg/kg/min was associated with lower initial blood glucose value and lower umbilical arterial pH.

CONCLUSION

Need for IV glucose infusion was associated with small size for GA, low initial glucose concentration, early-onset infection, and variables associated with perinatal hypoxia-asphyxia. The likelihood of a maximum GIR ≥ 10 mg/kg/min was greater in neonates with lower blood glucose value during the first 3 hours of observation and lower umbilical arterial pH.

KEY POINTS

· We studied 51,973 neonates ≥ 35 weeks' GA.. · We established a model predicting the need for IV glucose.. · We also predicted the need for a high rate of IV glucose..

Hyperglycemia and prematurity: a narrative review

Hyperglycemia is commonly encountered in extremely preterm newborns and physiologically can be attributed to immaturity in several biochemical pathways related to glucose metabolism. Although hyperglycemia is associated with a variety of adverse outcomes frequently described in this population, evidence for causality is lacking. Variations in definitions and treatment approaches have further complicated the understanding and implications of hyperglycemia on the immediate and long-term effects in preterm newborns. In this review, we describe the relationship between hyperglycemia and organ development, outcomes, treatment options, and potential gaps in knowledge that need further research. IMPACT: Hyperglycemia is common and less well described than hypoglycemia in extremely preterm newborns. Hyperglycemia can be attributed to immaturity in several cellular pathways involved in glucose metabolism in this age group. Hyperglycemia has been shown to be associated with a variety of adverse outcomes frequently described in this population; however, evidence for causality is lacking. Variations in definitions and treatment approaches have complicated the understanding and the implications of hyperglycemia on the immediate and long-term effects outcomes. This review describes the relationship between hyperglycemia and organ development, outcomes, treatment options, and potential gaps in knowledge that need further research.

What, why and how to monitor blood glucose in critically ill patients

Critically ill patients are prone to high glycemic variations irrespective of their diabetes status. This mandates frequent blood glucose (BG) monitoring and regulation of insulin therapy. Even though the most commonly employed capillary BG monitoring is convenient and rapid, it is inaccurate and prone to high bias, overestimating BG levels in critically ill patients. The targets for BG levels have also varied in the past few years ranging from tight glucose control to a more liberal approach. Each of these has its own fallacies, while tight control increases risk of hypoglycemia, liberal BG targets make the patients prone to hyperglycemia. Moreover, the recent evidence suggests that BG indices, such as glycemic variability and time in target range, may also affect patient outcomes. In this review, we highlight the nuances associated with BG monitoring, including the various indices required to be monitored, BG targets and recent advances in BG monitoring in critically ill patients.

Glycemic control and blood gas sampling frequency during continuous glucose monitoring in the intensive care unit: A before-and-after study

BACKGROUND

Whether subcutaneous continuous glucose monitoring (CGM) can safely replace intermittent arterial blood gas glucose analyses in intensive care unit (ICU) patients remains uncertain. We aimed to compare CGM to blood gas glucose values and assess whether CGM use reduces blood gas sampling frequency and glucose variability in ICU patients with type 2 diabetes managed with liberal glucose control.

METHODS

We used the FreeStyle Libre CGM in 15 ICU patients and compared their blood glucose metrics with a pre-CGM control population of 105 ICU patients with type 2 diabetes. Both groups received insulin to target glucose range of 10-14 mmol/L. We used linear regression analysis adjusted for illness severity to assess the association of CGM use with blood gas sampling frequency and glucose variability. We used mean absolute relative difference (MARD) and Clarke error grid analysis to assess accuracy of matched CGM-blood glucose values overall, across glucose stata (<10, 10-14, >14 mmol/L), and over time (≤48, 48-96, >96 h).

RESULTS

We analyzed 483 matched glucose values. Overall MARD was 11.5 (95% CI, 10.7-12.3)% with 99% of readings in Clarke zones A and B. MARD was 15.5% for glucose values <10 mmol/L, 11.1% at 10-14 mmol/L, and 11.4% >14 mmol/L. MARD was 13.8% in the first 48 h, 10.9% at 48-96 h, and 8.9% beyond 96 h. CGM use was associated with 30% reduction in blood gas sampling frequency. CGM use was not associated with glucose variability as determined by glycemic lability index or standard deviation of blood glucose.

CONCLUSIONS

In our cohort of ICU patients with type 2 diabetes receiving liberal glycemic control, CGM showed acceptable accuracy and was associated with a reduction in blood gas sampling frequency without compromising glucose control. Lowest accuracy was observed at glucose values below 10 mmol/L and during the first 48 h of CGM use.

Decreasing early hypoglycemia frequency in at-risk newborns after implementing a new hypoglycemia screening algorithm

BACKGROUND

Neonatal hypoglycemia may affect long-term neurodevelopment.

METHODS

Quality improvement (QI) initiative for Mother-Baby-Unit (MBU) admissions (birthweight ≥ 2100 g; ≥35 weeks' gestation) over two epochs from 2016-2019 to reduce the frequency of early (≤3 h) neonatal hypoglycemia in small and large newborns.

INTERVENTION

New algorithm using Olsen's growth curves, hypoglycemia thresholds of <2.22 mmol/L [40 mg/dL] (0-3 h) and <2.61 mmol/L [47 mg/dL] (>3 to 24 h), feeding optimization and 24-hour glucose checks for small for gestational age and preterm newborns.

RESULTS

Among 39,460 newborns, using subsets with identical screening criteria, early hypoglycemia decreased significantly after QI implementation among large for gestational age newborns with birthweight >3850 g (66%) and small for gestational age newborns with birthweight <2500 g (70%). Among all MBU admissions, the adjusted odds of any hypoglycemia in 24 h decreased (P < 0.001).

CONCLUSIONS

Feeding optimization may decrease early hypoglycemia frequency in large and small newborns.

Effect of Moderate and Severe Persistent Hyperglycemia on Outcomes in Patients With Intracerebral Hemorrhage

BACKGROUND AND PURPOSE

We evaluated the effect of persistent hyperglycemia on outcomes in 1000 patients with intracerebral hemorrhage enrolled within 4.5 hours of symptom onset.

METHODS

We defined moderate and severe hyperglycemia based on serum glucose levels ≥140 mg/dL-<180 and ≥180 mg/dL, respectively, measured at baseline, 24, 48, and 72 hours. Persistent hyperglycemia was defined by 2 consecutive (24 hours apart) serum glucose levels. We evaluated the relationship between moderate and severe hyperglycemia and death or disability (defined by modified Rankin Scale score of 4-6) at 90 days in the overall cohort and in groups defined by preexisting diabetes.

RESULTS

In the multivariate analysis, both moderate (odds ratio, 1.8 [95% CI, 1.1-2.8]) and severe (odds ratio, 1.8 [95% CI, 1.2-2.7]) hyperglycemia were associated with higher 90-day death or disability after adjusting for Glasgow Coma Scale score, hematoma volume, presence or absence of intraventricular hemorrhage, hyperlipidemia, cigarette smoking, and hypertension (no interaction between hyperglycemia and preexisting diabetes, P=0.996). Among the patients without preexisting diabetes, both moderate (odds ratio, 1.8 [95% CI, 1.0-3.2]) and severe (odds ratio, 2.0 [95% CI, 1.1-3.7]) hyperglycemia were associated with 90-day death or disability after adjusting for above mentioned potential confounders. Among the patients with preexisting diabetes, moderate and severe hyperglycemia were not associated with 90-day death or disability.

CONCLUSIONS

Persistent hyperglycemia, either moderate or severe, increased the risk of death or disability in nondiabetic patients with intracerebral hemorrhage.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT01176565.

Glycemic targets in critically ill adults: A mini-review

Illness-induced hyperglycemia impairs neutrophil function, increases pro-inflammatory cytokines, inhibits fibrinolysis, and promotes cellular damage. In turn, these mechanisms lead to pneumonia and surgical site infections, prolonged mechanical ventilation, prolonged hospitalization, and increased mortality. For optimal glucose control, blood glucose measurements need to be done accurately, frequently, and promptly. When choosing glycemic targets, one should keep the glycemic variability < 4 mmol/L and avoid targeting a lower limit of blood glucose < 4.4 mmol/L. The upper limit of blood glucose should be set according to casemix and the quality of glucose control. A lower glycemic target range (i.e., blood glucose 4.5-7.8 mmol/L) would be favored for patients without diabetes mellitus, with traumatic brain injury, or who are at risk of surgical site infection. To avoid harm from hypoglycemia, strict adherence to glycemic control protocols and timely glucose measurements are required. In contrast, a higher glycemic target range (i.e., blood glucose 7.8-10 mmol/L) would be favored as a default choice for medical-surgical patients and patients with diabetes mellitus. These targets may be modified if technical advances for blood glucose measurement and control can be achieved.

Association Between Intraoperative Blood Glucose and Anastomotic Leakage in Colorectal Surgery

BACKGROUND

Perioperative hyperglycemia is a known risk factor for postoperative complications after colorectal surgery. The aim of this study was to investigate whether intraoperative blood glucose values are associated with colorectal anastomotic leakage in diabetic and non-diabetic patients undergoing colorectal surgery.

METHODS

This is an additional analysis of a previously published prospective, observational cohort study (the LekCheck study). Fourteen hospitals in Europe and Australia collected perioperative data. Consecutive adult patients undergoing colorectal surgery with primary anastomosis between 2016 and 2018 were included. From all patients, preoperative diabetic status was known and intraoperative blood glucose was determined just prior to the creation of the anastomosis. The primary outcome was the occurrence of anastomotic leakage within 30 days postoperatively.

RESULTS

Of 1474 patients (mean age 68 years), 224 patients (15%) had diabetes mellitus, 737 patients (50%) had intraoperative hyperglycemia (≥126 mg/dL, ≥7.0 mmol/L), and 129 patients (8.8%) developed anastomotic leakage. Patients with intraoperative hyperglycemia had higher anastomotic leakage rates compared to patients with a normal blood glucose level (12% versus 5%, P<0.001). Anastomotic leakage rate did not significantly differ between diabetic and non-diabetic patients (12% versus 8%, P=0.058). Logistic regression analyses showed that higher blood glucose levels were associated with an increasing leakage risk in non-diabetic patients only.

CONCLUSION

Incidence and severity of intraoperative hyperglycemia are associated with anastomotic leakage in non-diabetic patients. Whether hyperglycemia is an epiphenomenon, a marker for other risk factors or a potential modifiable risk factor per se for anastomotic leakage requires future research.

Dual-hormone artificial pancreas for management of type 1 diabetes: Recent progress and future directions

Over the last few years, technological advances have led to tremendous improvement in the management of type 1 diabetes (T1D). Artificial pancreas systems have been shown to improve glucose control compared with conventional insulin pump therapy. However, clinically significant hypoglycemic and hyperglycemic episodes still occur with the artificial pancreas. Postprandial glucose excursions and exercise-induced hypoglycemia represent major hurdles in improving glucose control and glucose variability in many patients with T1D. In this regard, dual-hormone artificial pancreas systems delivering other hormones in addition to insulin (glucagon or amylin) may better reproduce the physiology of the endocrine pancreas and have been suggested as an alternative tool to overcome these limitations in clinical practice. In addition, novel ultra-rapid-acting insulin analogs with a more physiological time-action profile are currently under investigation for use in artificial pancreas devices, aiming to address the unmet need for further improvements in postprandial glucose control. This review article aims to discuss the current progress and future outlook in the development of novel ultra-rapid insulin analogs and dual-hormone closed-loop systems, which offer the next steps to fully closing the loop in the artificial pancreas.

The Oral Glucose Tolerance Test-Is It Time for a Change?-A Literature Review with an Emphasis on Pregnancy

Globally, gestational diabetes (GDM) is increasing at an alarming rate. This increase is linked to the rise in obesity rates among women of reproductive age. GDM poses a major global health problem due to the related micro- and macro-vascular complications of subsequent Type 2 diabetes and the impact on the future health of generations through the long-term impact of GDM on both mothers and their infants. Therefore, correctly identifying subjects as having GDM is of utmost importance. The oral glucose tolerance test (OGTT) has been the mainstay for diagnosing gestational diabetes for decades. However, this test is deeply flawed. In this review, we explore a history of the OGTT, its reproducibility and the many factors that can impact its results with an emphasis on pregnancy.

Impact of point-of-care creatinine monitoring on early detection of acute kidney injury in critical illness

PURPOSE

To assess the utility and accuracy of creatinine measurement using point-of-care (POC) blood gas analysis compared to standard laboratory assay and to assess the effectiveness of frequent creatinine monitoring using POC blood gas analysis with respect to early detection of acute kidney injury (AKI).

METHODS

We performed a single center retrospective observational study in 398 patients admitted to the intensive care unit. We investigated the clinical concordance of creatinine values measured by POC blood gas analysis (Cr-BG) compared to those measured by laboratory assay (Cr-lab). We compared the time to reach AKI diagnosis according to the KDIGO criteria using Cr-BG (KD-BG) to the standard criteria using Cr-lab (KD-lab).

RESULTS

Cr-BG correlated well with Cr-lab for day 1 (n = 375, R² = 0.98, p < 0.001) and during the whole study period (n = 1258, R² = 0.99, p < 0.001). The KD-BG measurement allowed the identification of 6.3% more patients (60.6%) as AKI than the KD-lab measurement. Approximately one-third of the patients were staged as AKI using the KD-BG measurement more than 6 h earlier than that using the KD-lab measurement.

CONCLUSIONS

The KDIGO criteria using POC blood gas analysis were clinically useful. Frequent creatinine monitoring using POC analysis can allow an earlier detection of AKI.

Blood glucose control in the intensive care unit: Where is the data?

Blood glucose control, including hyperglycemia correction, maintaining glucose at optimal level and avoiding hypoglycemia, is a challenge clinicians face every day in intensive care units (ICUs). If managed inadequately, its related mortality can increase. Prior to 2001, no relevant data from randomized, controlled studies assessing glucose control in the ICU were available. In the past 18 years, however, many clinical trials have defined criteria for managing abnormal blood glucose levels, as well as provided suggestions for glycemic monitoring. Point-of-care blood glucose monitors have become the preferred bedside technology to aid in glycemic management. In addition, in some institutions, continuous glucose monitoring is now available. Cost-effectiveness of adequate glycemic control in the ICU must be taken into consideration when addressing this complex issue. Newer types of glycemic monitoring may reduce nursing staff fatigue and shorten times for the treatment of hyperglycemia or hypoglycemia. There are a variety of glycemic care protocols available. However, not all ICU clinicians are aware of them. The following minireview describes some of these concepts.

The effect of a low carbohydrate formula on glycaemia in critically ill enterally-fed adult patients with hyperglycaemia: A blinded randomised feasibility trial

BACKGROUND

Enteral nutrition is a source of carbohydrate that may exacerbate hyperglycaemia. Its treatment, insulin, potentially exacerbates glycaemic variability.

METHODS

This was a prospective, parallel group, blinded, randomised feasibility trial. Patients were eligible if 18 years or over when admitted to the intensive care unit and receiving enteral nutrition (EN) exclusively with two consecutive blood glucose > 10 mmol/L. A standardized glucose management protocol determined administration of insulin. Key outcome measures were insulin administered and glycaemic variability (coefficient of variation) over the first 48 h.

RESULTS

41 patients were randomized to either standard EN (14.1 g/100 mL carbohydrate; n = 20) or intervention EN (7.4 g/100 mL carbohydrate; n = 21). Overall 59% were male, mean (±SD) age of 62.3 years ± 10.4, APACHE II score of 16.5 ± 7.8 and a median (IQR) Body Mass Index 29.0 kg/m² (25.2-35.5). Most patients (73%) were mechanically ventilated. Approximately half (51%) were identified as having diabetes prior to ICU admission. Patients in the intervention arm received less insulin over the 48 h study period than those in the control group (mean insulin units over study period (95% CI) 45.0 (24.4-68.7) vs. 107 (56.1-157.9) units; p = 0.02) and had lower mean glycaemic variability (12.6 vs. 15.9%, p = 0.01). There was a small difference in the mean percentage of energy requirements met (intervention: 72.9 vs. control: 79.1%; p = 0.4) or protein delivered (78.2 vs. 85.4%; p = 0.3).

CONCLUSIONS

A low carbohydrate formula was associated with reduced insulin use and glycaemic variability in enterally-fed critically ill patients with hyperglycaemia. Further large trials are required to determine the impact of this formula on clinical outcomes. Registered under Australian and New Zealand Clinical Trials Registry, ANZCTR number: 12614000166673.

Recent advances in perioperative glucose monitoring

PURPOSE OF REVIEW

There is ongoing controversy surrounding the use of glucose monitoring in the perioperative setting. It is an important aspect of patient care, but the best way to go about monitoring this parameter is still up for debate. This article will review previously established data and new developments in this field.

RECENT FINDINGS

Several different methods exist to measure blood glucose levels in the perioperative setting, including central laboratory devices, blood gas analyzers, and point-of-care devices. However, it has been recommended that point-of-care devices not be used on 'critically ill' patients, which throws into question the common use of these devices perioperatively. Recently, the Centers for Medicare and Medicaid placed a moratorium on this recommendation, and these devices continue to be a staple in the perioperative setting, but there are other methods of glucose monitoring that can be employed.

SUMMARY

The monitoring of blood glucose levels in the perioperative patient remains an important part of patient care; however, debate still exist on how best to reliably measure blood glucose levels in the most effective manner.

Comparison of Space Glucose Control and Routine Glucose Management Protocol for Glycemic Control in Critically Ill Patients: A Prospective, Randomized Clinical Study

Background:

The Space Glucose Control (SGC) system is a computer-assisted device combining infusion pumps with the enhanced Model Predictive Control algorithm to achieve the target blood glucose (BG) level safely. The objective of this study was to evaluate the efficacy and safety of glycemic control by SGC with customized BG target range of 5.8–8.9 mmol/L in the critically ill patients.

Methods:

It is a randomized controlled trial of seventy critically ill patients with mechanical ventilation and hyperglycemia (BG ≥ 9.0 mmol/L). Thirty-six patients in the SGC group and 34 in the routine glucose management group were observed for three consecutive days. Target BG for both groups was 5.8–8.9 mmol/L. The primary outcome was the percentage time in the target range.

Results:

The percentage time within BG target range in the SGC group (69 ± 15%) was significantly higher than in the routine management group (52 ± 24%; P < 0.01). No measurement was ≤2.2 mmol/L, and there was only one episode of hypoglycemia (2.3–3.3 mmol/L) in each group. The average BG was significantly lower in the SGC group (7.8 ± 0.7 mmol/L) than in the routine management group (9.1 ± 1.6 mmol/L, P < 0.001). Target BG level was reached earlier in the SGC group than routine management group (2.5 ± 2.9 vs. 12.1 ± 15.3 h, P = 0.001). However, the SGC group performed worse for daily insulin requirement (59.8 ± 39.3 vs. 28.4 ± 36.7 U, P = 0.001) and sampling interval (2.0 ± 0.5 vs. 3.7 ± 0.5 h, P < 0.001) than the routine management group did. Multiple linear regression showed that the intervention group remained a significant individual predictor (P < 0.001) of the percentage time in target range.

Conclusions:

The SGC system, with a BG target of 5.8–8.9 mmol/L, resulted in effective and reliable glycemic control with few hypoglycemic episodes in critically ill patients with mechanical ventilation and hyperglycemia. However, the workload was increased.

Trial Registration:

http://www.clinicaltrials.gov, NCT 02491346; https://www.clinicaltrials.gov/ct2/show/NCT02491346?term=NCT02491346&cond=Hyperglycemia&cntry1=ES%3ACN&rank=1.

Blood Gas Analyzer Accuracy of Glucose Measurements

OBJECTIVE

To investigate the comparability of glucose levels measured with blood gas analyzers (BGAs) and by central laboratories (CLs).

MATERIAL AND METHODS

Glucose measurements obtained between June 1, 2007, and March 1, 2016, at the Vanderbilt University Medical Center were reviewed. The agreement between CL and BGA results were assessed using Bland-Altman, consensus error grid (CEG), and surveillance error grid (SEG) analyses. We further analyzed the BGAs' performance against the US Food and Drug Administration (FDA) 2014 draft guidance and 2016 final guidance for blood glucose monitoring and the International Organization for Standardization (ISO) 15197:2013 standard.

RESULTS

We analyzed 2671 paired glucose measurements, including 50 pairs of hypoglycemic values (1.9%). Bland-Altman analysis yielded a mean bias of -3.1 mg/dL, with 98.1% of paired values meeting the 95% limits of agreement. In the hypoglycemic range, the mean bias was -0.8 mg/dL, with 100% of paired values meeting the 95% limits of agreement. When using CEG analysis, 99.9% of the paired values fell within the no risk zone. Similar results were found using SEG analysis. For the FDA 2014 draft guidance, our data did not meet the target compliance rate. For the FDA 2016 final guidance, our data partially met the target compliance rate. For the ISO standard, our data met the target compliance rate.

CONCLUSION

In this study, the agreement for glucose measurement between common BGAs and CL instruments met the ISO 2013 standard. However, BGA accuracy did not meet the stricter requirements of the FDA 2014 draft guidance or 2016 final guidance. Fortunately, plotting these results on either the CEG or the SEG revealed no results in either the great or extreme clinical risk zones.

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.

Evaluation of CareSens POCT Devices for Glucose Testing in the Routine Hospital Setting

INTRODUCTION

Glucose meters are used routinely in hospital wards to manage blood glucose levels in patients requiring frequent monitoring of blood glucose.

OBJECTIVE

Our institution has 50 POC instruments utilized by diverse population of all ages and medical conditions. The primary objective of our study was to investigate whether all these CareSens glucose meters (I-sense Inc, Seoul, South Korea) results in hospitalized patients during routine clinical care jointly satisfy the specified quality specifications, as defined by Clinical and Laboratory Standards Institute (CLSI) guideline POCT12-A3.

MATERIALS AND METHODS

The records of hospitalized patients who underwent simultaneous measures of glucose levels with both glucose meters and a central laboratory analyser between January and June 2013 were retrospectively analysed. We also performed a prospective evaluation of the accuracy of the CareSens glucose Strip.

RESULTS

Glucose concentrations measured in 840 patients ranged from 1.66 to 31.72 mmol/L The Bland-Altman difference plot between the auto analyser and all the 50 CareSens glucosemeters revealed a mean bias of -2.2%, with analytical biases for the two methods varying from -31.1% to 26.8%. Eighty four percent of the glucose meter's glucose values were within ± 12.5% for values 5.54 mmol/L of the comparative laboratory glucose values and 93% of the results were within 20% of the reference for glucose >4.2 mmol/L and 65% of the results were within 0.8 mmol/L for glucose <4.2 mmol/L.

CONCLUSION

CareSens glucose meter readings in hospital settings, especially in hypoglycaemic patients, should be confirmed by central laboratory analysers whenever possible.

Prolonged bilateral reactive miosis as a symptom of severe insulin intoxication

Patient: Female, 64

Final Diagnosis: Insulin self poisoning

Symptoms: Coma

Medication: —

Clinical Procedure: Supportive care

Specialty: Critical Care Medicine

Analysis: New point-of-care blood glucose monitoring system for the hospital demonstrates satisfactory analytical accuracy using blood from critically ill patients--an important step toward improved blood glucose control in the hospital

Patients managed in the intensive care units (ICUs) and general wards of the hospital experience a high incidence of hyperglycemia, hypoglycemia, and glycemic variability, despite significant hospital resources devoted to glucose control. Optimized glucose meters and monitoring systems are required to improve the safety and efficacy of insulin delivery and glucose control in the hospital. Safe insulin dosing requires timely and accurate glucose measurements, especially during dynamic changes in nutrition, insulin sensitivity, and physiological stress. In the current issue of Journal of Diabetes Science and Technology, Mitsios and coauthors describe the analytical accuracy of the new Accu-Check® Inform II blood glucose (BG) monitoring system commercialized by F. Hoffmann-La Roche Ltd. The point-of-care glucose meter achieved the desired degree of accuracy and precision, as defined by Clinical and Laboratory Standards Institute POCT12-A3 guidelines when evaluated using venous blood from 600 critically ill patients from multiple ICUs at two medical centers. Venous whole blood samples were used to obtain glucose meter results in duplicate. The remaining blood sample was centrifuged to obtain plasma for central hospital laboratory testing using the hexokinase method within 5 min of meter testing. A total of 98.8% of the 1200 Accu-Check Inform II meter's glucose values were within ± 12.5% (± 12 mg/dl) of the mean laboratory glucose value, and 99.8% were within ± 20% (± 20 mg/dl), thus meeting the Clinical and Laboratory Standards Institute criteria. Future studies are required to evaluate the clinical performance of the new BG monitoring system in the intended-use patient populations and critical care environments, using arterial, peripheral venous, central venous, and capillary blood samples.