Implementation of Continuous Glucose Monitoring in Critical Care: A Scoping Review

Deep tissue sensing of chiral molecules using polarization-enhanced photoacoustics

Chiral molecule sensing is typically performed using techniques like chromatography, electrophoresis, enzymatic assays, mass spectrometry, and chiroptical methods. While polarimetry allows for in vivo sensing up to 1 mm depth using ultraviolet-visible light, it is limited by dominant light scattering beyond this depth. We propose that photoacoustic sensing in the near-infrared II (NIR-II) window can enable deep tissue sensing as acoustic waves scatter less than light. To achieve this, we developed a photoacoustic polarization-enhanced optical rotation sensing (PAPEORS) system, capable of estimating optical rotation from photoacoustic signals and correlating it with chiral molecular concentration for depths up to 3.5 mm. Experiments were conducted using aqueous glucose solutions, naproxen, serum-based glucose samples, and ex vivo chicken tissue. PAPEORS achieved a detection limit of 80 mg/dl while using circularly polarized light with serum samples, demonstrating the potential for deep-tissue chiral molecular sensing. PAPEORS holds promise for in vivo sensing and easy miniaturization using single wavelength.

Continuous peri-operative glucose monitoring in noncardiac surgery: A systematic review

BACKGROUND

Glucose management is an important component of peri-operative care. The usefulness of continuous glucose monitoring (CGM) in noncardiac surgery is uncertain.

OBJECTIVE

To systematically assess the glycaemic profile and clinical outcome of patients equipped with a CGM device during the peri-operative period in noncardiac surgery.

DESIGN

Systematic review.

DATA SOURCES

Electronic databases were systematically searched up to July 2024.

ELIGIBILITY CRITERIA

Any studies performed in the peri-operative setting using a CGM device were included. Closed-loop systems also administering insulin were excluded. Analyses were stratified according to diabetes mellitus status and covered intra-operative and postoperative data. Outcomes included glycaemic profile (normal range 3.9 to 10.0 mmol l -1 ), complications, adverse events, and device dysfunction.

RESULTS

Twenty-six studies (1016 patients) were included. Twenty-four studies were not randomised, and six used a control arm for comparison. In bariatric surgery, diabetes mellitus patients had a mean ± SD glucose of 5.6 ± 0.5 mmol l -1 , with 15.4 ± 8.6% time below range, 75.3 ± 5.5% in range and 9.6 ± 6.7% above range. During major surgery, diabetes mellitus patients showed a mean glucose of 9.6 ± 1.1 mmol l -1 , with 9.5 ± 9.1% of time below range, 56.3 ± 13.5% in range and 30.6 ± 13.9% above range. In comparison, nondiabetes mellitus patients had a mean glucose of 6.4 ± 0.6 mmol l -1 , with 6.7 ± 8.4% time below range, 84.6 ± 15.5% in range and 11.2 ± 4.9% above range. Peri-operative complications were reported in only one comparative study and were similar in CGM and control groups. Device-related adverse events were rare and underreported. In 9.21% of cases, the devices experienced dysfunctions such as accidental removal and issues with sensors or readers.

CONCLUSION

Due to the limited number of controlled studies, the impact of CGM on postoperative glycaemic control and complications compared with point-of-care testing remains unknown. Variability in postoperative glycaemic profiles and a device dysfunction rate of 1 in 10 suggest CGM should be investigated in a targeted surgical group.

Diabetes Technology Use in Special Populations: A Narrative Review of Psychosocial Factors

As diabetes technologies continue to advance, their use is expanding beyond type 1 diabetes to include populations with type 2 diabetes, older adults, pregnant individuals, those with psychiatric conditions, and hospitalized patients. This review examines the psychosocial outcomes of these technologies across these diverse groups, with a focus on treatment satisfaction, quality of life, and self-management behaviors. Despite demonstrated benefits in glycemic outcomes, the adoption and sustained use of these technologies face unique challenges in each population. By highlighting existing research and identifying gaps, this review seeks to emphasize the need for targeted studies and tailored support strategies to understand and optimize psychosocial outcomes and well-being.

Accuracy of continuous glucose monitoring systems in intensive care unit patients: a scoping review

PURPOSE

Glycemic control poses a challenge in intensive care unit (ICU) patients and dysglycemia is associated with poor outcomes. Continuous glucose monitoring (CGM) has been successfully implemented in the type 1 diabetes out-patient setting and renewed interest has been directed into the transition of CGM into the ICU. This scoping review aimed to provide an overview of CGM accuracy in ICU patients to inform future research and CGM implementation.

METHODS

We systematically searched PubMed and EMBASE between 5th of December 2023 and 21st of May 2024 and reported findings in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline for scoping reviews (PRISMA-ScR). We assessed studies reporting the accuracy of CGM in the ICU and report study characteristics and accuracy outcomes.

RESULTS

We identified 2133 studies, of which 96 were included. Most studies were observational (91.7%), conducted in adult patients (74%), in mixed ICUs (47.9%), from 2014 and onward, and assessed subcutaneous CGM systems (80%) using arterial blood samples as reference test (40.6%). Half of the studies (56.3%) mention the use of a prespecified reference test protocol. The mean absolute relative difference (MARD) ranged from 6.6 to 30.5% for all subcutaneous CGM studies. For newer factory calibrated CGM, MARD ranged from 9.7 to 20.6%. MARD for intravenous CGM was 5-14.2% and 6.4-13% for intraarterial CGM.

CONCLUSIONS

In this scoping review of CGM accuracy in the ICU, we found great diversity in accuracy reporting. Accuracy varied depending on CGM and comparator, and may be better for intravascular CGM and potentially lower during hypoglycemia.

Expanding the horizon of continuous glucose monitoring into the future of pediatric medicine

Glucose monitoring has rapidly evolved with the development of minimally invasive continuous glucose monitoring (CGM) using interstitial fluid. It is recommended as standard of care in the ambulatory setting, nearly replacing capillary glucose testing in those with access to CGM. The newest CGM devices continue to be smaller and more accurate, and integration with automated insulin delivery systems has further revolutionized the management of diabetes, leading to successful improvements in care and quality of life. Many studies confirm accuracy and application of CGM in various adult inpatient settings. Studies in adult patients increased during the COVID 19 Pandemic, but despite reassuring results, inpatient CGM use is not yet approved by the FDA. There is a lack of studies in inpatient pediatric settings, although data from the NICU and PICU have started to emerge. Given the exponential increase in the use of CGM, it is imperative that hospitals develop protocols for CGM use, with a need for ongoing implementation research. In this review we describe how CGM systems work, discuss benefits and barriers, summarize research in inpatient pediatric CGM use, explore gaps in research design along with emerging recommendations for inpatient use, and discuss overall CGM utility beyond outpatient diabetes management. IMPACT: Current CGM systems allow for uninterrupted monitoring of interstitial glucose excursions, and have triggered multiple innovations including automated insulin delivery. CGM technology has become part of standard of care for outpatient diabetes management, endorsed by many international medical societies, now with significant uptake, replacing capillary glucose testing for daily management in patients with access to CGM technology. Although CGM is not approved by the FDA for inpatient hospital use, studies in adult settings support its use in hospitals. More studies are needed for pediatrics. Implementation research is paramount to expand the role of CGM in the inpatient setting and beyond.

Accuracy of a Continuous Glucose Monitor in the Intensive Care Unit: A Proposed Accuracy Standard and Calibration Protocol for Inpatient Use

Background and Aims: Guidelines now recommend inpatient continuous glucose monitor (CGM) use with confirmatory blood glucose measurements. However, the Food and Drug Administration has not yet officially approved CGM for inpatient use in large part because its accuracy has not been established in this setting. We tested the accuracy of the Dexcom G6 (G6) in 28 adults on an insulin infusion in a medical-surgical intensive care unit with 1064 matched CGM and arterial point-of-care pairs. Methods: The participants were on average 57.29 (SD 2.39) years, of whom 13 had a prior diagnosis of diabetes and 14 were admitted for a surgical diagnosis. The first 19 participants received the G6 without calibration and had a mean absolute relative difference (MARD) of 13.19% (IQR 5.11, 19.03) across 659 matched pairs, which just meets the critical care expert recommendation of MARD <14%. We then aimed to improve accuracy for the subsequent 9 participants using a calibration protocol. Results: The MARD for calibrated participants was 9.65% (3.03, 13.33), significantly lower than for uncalibrated participants (P < 0.001). Calibration also demonstrated excellent safety with 100% of values within the Clarke Error Grid zones A and B compared with 99.07% without calibration. Our protocol achieved the lowest MARD and safest CEG profile in the critical care setting and well exceeds the critical care expert recommendations. Our large sample of heterogenous critically ill patients also reached comparable accuracy to the MARD of 9% for G6 in outpatients. We believe our calibration protocol will allow G6 to be used with sufficient accuracy in inpatients.

Are we Ready for Real-Time Continuous Glucose Monitoring in the Hospital Setting? Benefits, Challenges, and Practical Approaches for Implementation : Case Vignette: Remote Real-Time Continuous Glucose Monitoring for Hospitalized Care in Quincy Koala

PURPOSE OF REVIEW

While preliminary evidence for use of real-time continuous glucose monitoring (rtCGM) in the hospital setting is encouraging, challenges with currently available devices and technology will need to be overcome as part of real-world integration. This paper reviews the current evidence and guidelines regarding use of rtCGM in the hospital and suggests a practical approach to implementation.

RECENT FINDINGS

There is now a considerable body of real-world evidence on the benefits of reducing dysglycemia in the hospital using both traditional point-of-care (POC) glucose testing and rtCGM. Benefits of rtCGM include decreased frequency of hypo- and hyperglycemia with reduced need of frequent POC checks and it is both feasible and well-accepted by nursing staff and providers. If expansion to additional sites is to be considered, practical solutions will need to be offered. Recommendations for an operational workflow and tools are described to guide implementation in the non-ICU setting. Further testing in randomized controlled trials and real-world dissemination and implementation designs is needed, together with industry and technology collaborations, to further streamline the integration into health systems.

Empowering Hospitalized Patients With Diabetes: Implementation of a Hospital-wide CGM Policy With EHR-Integrated Validation for Dosing Insulin

OBJECTIVE

We aimed to assess the feasibility, clinical accuracy, and acceptance of a hospital-wide continuous glucose monitoring (CGM) policy with electronic health record (EHR)-integrated validation for insulin dosing.

RESEARCH DESIGN AND METHODS

A hospital policy was developed and implemented at Stanford Health Care for using personal CGMs in lieu of fingerstick blood glucose (FSBG) monitoring. It included requirements specific to each CGM, accuracy monitoring protocols, and EHR integration. User experience surveys were conducted among a subset of patients and nurses.

RESULTS

From November 2022 to August 2023, 135 patients used the CGM protocol in 185 inpatient encounters. This group included 27% with type 1 diabetes and 24% with automated insulin delivery systems. The most-used CGMs were Dexcom G6 (44%) and FreeStyle Libre 2 (43%). Of 1,506 CGM validation attempts, 87.8% met the 20% or 20 mg/dL (%20/20) criterion for CGM-based insulin dosing and 99.3% fell within Clarke zones A or B. User experience surveys were completed by 27 nurses and 46 patients. Most nurses found glucose management under the protocol effective (74%), easy to use (67%), and efficient (63%); 80% of nurses preferred inpatient CGM to FSBG. Most patients liked the CGM protocol (63%), reported positive CGM interactions with nursing staff (63%), and felt no significant interruptions to their diabetes management (63%).

CONCLUSIONS

Implementation of a hospital-wide inpatient CGM policy supporting multiple CGM types with real-time accuracy monitoring and integration into the EHR is feasible. Initial feedback from nurses and patients was favorable, and further investigation toward broader use and sustainability is needed.

Association between the stress hyperglycemia ratio and mortality in patients with acute ischemic stroke

The stress hyperglycemia ratio (SHR) is established as a reliable marker for assessing the severity of stress-induced hyperglycemia. While its effectiveness in managing patients with Acute Ischemic Stroke (AIS) remains to be fully understood. We aim to explore the relationship between SHR and clinical prognosis in AIS patients and to assess how diabetes status influences this relationship. In this study, we analyzed data from the Medical Information Mart for Intensive Care (MIMIC-IV) database, selecting patients with AIS who required ICU admission. These patients were categorized into tertiles based on their SHR levels. We applied Cox hazard regression models and used restricted cubic spline (RCS) curves to investigate relationships between outcomes and SHR. The study enrolled a total of 2029 patients. Cox regression demonstrated that a strong correlation was found between increasing SHR levels and higher all-cause mortality. Patients in the higher two tertiles of SHR experienced significantly elevated 30-day and 90-day mortality rates compared to those in the lowest tertile. This pattern remained consistent regardless of diabetes status. Further, RCS analysis confirmed a progressively increasing risk of all-cause mortality with higher SHR levels. The findings indicate that SHR is association with increased 30-day and 90-day mortality among AIS patients, underscoring its potential value in risk stratification. Although the presence of diabetes may weaken this association, significant correlations persist in diabetic patients.

Society of Critical Care Medicine Guidelines on Glycemic Control for Critically Ill Children and Adults 2024

RATIONALE

Maintaining glycemic control of critically ill patients may impact outcomes such as survival, infection, and neuromuscular recovery, but there is equipoise on the target blood levels, monitoring frequency, and methods.

OBJECTIVES

The purpose was to update the 2012 Society of Critical Care Medicine and American College of Critical Care Medicine (ACCM) guidelines with a new systematic review of the literature and provide actionable guidance for clinicians.

PANEL DESIGN

The total multiprofessional task force of 22, consisting of clinicians and patient/family advocates, and a methodologist applied the processes described in the ACCM guidelines standard operating procedure manual to develop evidence-based recommendations in alignment with the Grading of Recommendations Assessment, Development, and Evaluation Approach (GRADE) methodology. Conflict of interest policies were strictly followed in all phases of the guidelines, including panel selection and voting.

METHODS

We conducted a systematic review for each Population, Intervention, Comparator, and Outcomes question related to glycemic management in critically ill children (≥ 42 wk old adjusted gestational age to 18 yr old) and adults, including triggers for initiation of insulin therapy, route of administration, monitoring frequency, role of an explicit decision support tool for protocol maintenance, and methodology for glucose testing. We identified the best available evidence, statistically summarized the evidence, and then assessed the quality of evidence using the GRADE approach. We used the evidence-to-decision framework to formulate recommendations as strong or weak or as a good practice statement. In addition, "In our practice" statements were included when the available evidence was insufficient to support a recommendation, but the panel felt that describing their practice patterns may be appropriate. Additional topics were identified for future research.

RESULTS

This guideline is an update of the guidelines for the use of an insulin infusion for the management of hyperglycemia in critically ill patients. It is intended for adult and pediatric practitioners to reassess current practices and direct research into areas with inadequate literature. The panel issued seven statements related to glycemic control in unselected adults (two good practice statements, four conditional recommendations, one research statement) and seven statements for pediatric patients (two good practice statements, one strong recommendation, one conditional recommendation, two "In our practice" statements, and one research statement), with additional detail on specific subset populations where available.

CONCLUSIONS

The guidelines panel achieved consensus for adults and children regarding a preference for an insulin infusion for the acute management of hyperglycemia with titration guided by an explicit clinical decision support tool and frequent (≤ 1 hr) monitoring intervals during glycemic instability to minimize hypoglycemia and against targeting intensive glucose levels. These recommendations are intended for consideration within the framework of the patient's existing clinical status. Further research is required to evaluate the role of individualized glycemic targets, continuous glucose monitoring systems, explicit decision support tools, and standardized glycemic control metrics.

Associations of predominant night-eating with plasma glycemic status and continuous glucose monitoring measures among pregnant women

BACKGROUND & AIMS

To examine whether predominant night-eating, defined as more than 50% of total daily energy intake consumed between 1900 and 0659 h, is associated with glycemic outcomes in pregnancy.

METHODS

This was a prospective cohort study of 277 healthy pregnant women with complete 4-day dietary intake records at 18-24 weeks gestation, recruited from KK Women's and Children's Hospital, Singapore. Primary outcomes were fasting, 1-h, and 2-h plasma glucose after a 75-g oral glucose tolerance test at 24-28 weeks gestation. Secondary outcomes were gestational diabetes mellitus (GDM), fasting insulin, homeostasis model assessment of insulin resistance (HOMA2-IR), β-cell function (HOMA2-%B), and continuous glucose monitoring (CGM) measures. Glucose variables in continuous form were loge-transformed before analyses.

RESULTS

Predominant night-eating (11.6%) was associated with higher fasting glucose (geometric mean ratio (95% confidence interval) 1.05 (1.01, 1.08)) and 1-h glucose (1.11 (1.01, 1.21)), but not with 2-h glucose or GDM risk. Predominant night-eating women had lower fasting insulin (0.77 (0.63, 0.95)), lower HOMA2-IR (0.78 (0.64, 0.97)), and lower HOMA2-%B (0.77 (0.67, 0.89)) than their predominant day-eating counterparts. For CGM measures, predominant night-eating was associated with higher mean glucose (1.07 (1.00, 1.15)), higher glucose management indicator (1.05 (1.00, 1.10)), and higher overall glucose levels throughout 24 h (1.10 (1.02, 1.19)). All these associations were adjusted for socio-demographic, lifestyle factors, and diet composition.

CONCLUSION

Predominant night-eating was mainly associated with less desirable glycemic outcomes during pregnancy. Future studies should explore dietary interventions aimed at reducing consumption of relatively more calories at night than day during pregnancy.