Assessment of the Accuracy,Feasibility,Safety of Continuous Glucose Monitoring System

Study Overview
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Brief Summary
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Real-time continuous glucose monitoring system (CGMS) has been attempted to be used in ICU, but its feasibility, accuracy and confounding factors are controversial.

Detailed Description
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Acute glucose metabolic disorder (hyperglycemia, hypoglycemia and high glucose variability) is common during critical illness and associated with poor prognosis.Continuous glucose monitoring system (CGMS), which providing continuous glucose values, is promising to overcome these problems mentioned above and finally optimize glucose control.But its feasibility, accuracy and confounding factors are controversial.The aims of this study is to assess the accuracy, feasibility and safety of CGMS in daily routine in a general ICU in comparison with simultaneous laboratory arterial blood glucose (ABG) values

Official Title
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The Accuracy, Feasibility, Safety and Confounding Factors of Real-time Continuous Glucose Monitoring System

Conditions
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Continuous Glucose Monitoring System, Accuracy, Feasibility, Safety

Intervention / Treatment
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* Device: Real-time continuous blood glucose monitoring system(CGMS)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Inclusion criteria: Critically ill patients who were older than 18 years old and expected length of ICU stay longer than 48 hours Exclusion Criteria: 1) they were pregnant.2) had broken skin. 3) had a platelet count of less than 30 × 109/L 4) had participated in another trial.5) diabetic ketoacidosis or hyperosmotic coma.6) judged to be improper to complete this trial by the investigator

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Enrolled Patients<br>A total of 20 patients were enrolled for the place of CGMS. Arterial blood glucose (ABG) were recorded every four hours. The duration of monitoring set was 5 days.CGMS were compared with ABG at the same time point. A total of 600 pairs of glucose level were collected | Device: Real-time continuous blood glucose monitoring system(CGMS)<br>* A total of 20 patients were enrolled for the place of CGMS.CGMS were placed on the right chest wall of each patients and recorded the interstitial glucose. Arterial blood glucose (ABG) were recorded every four hours. The duration of monitoring set was 5 days.CGMS were compared with ABG at the same time point. A total of 600 pairs of glucose level were collected<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The Spearman correlation analysis | correlation coefficient (between 0.3 and 0.5):low correlation;(between 0.5 and 0.8);moderate correlation;(above 0.8):high correlation | CGMS will be used up to 5 days | 
| Bland-altman analysis | more than 95% CGMS-arterial blood glucose(ABG) data pairs should be within the agreement range. | CGMS will be used up to 5 days | 
| The International Standardization Organization (ISO) criteria | more than 95% of CGMS readings should be within 0.83mmol/L( of the reference values when the reference value is ≤5.56mmol/L and within 15.0% of the reference values when the reference value is >5.56mmol/L | CGMS will be used up to 5 days | 
| Mean absolute relative difference(MARD) and possible confounding factors | The MARD in critical ill patients should not be more than 14%.Stratified MARD according to 7 factors(history of diabetes, blood glucose variability （determined using standard deviation of blood glucose）, glucose ranges(<4.4mmol/L,4.4-10mmol/L,>10mmol/L）, vasoactive drugs,continuous renal replacement therapy(CRRT), glucocorticoids, enteral nutrition(EN) and parenteral nutrition(PN) will be calculated and made a comparison. | CGMS will be used up to 5 days | 
| Clarke error grid analysis | More than 98% data pairs should locate in accuracy zone(Zone A) and clinically acceptable zone(Zone B) | CGMS will be used up to 5 days | 
| Surveillance error grid | There is no definite data field.The results will be analyzed comprehensively | CGMS will be used up to 5 days |