Use of a continuous glucose sensor in an extracorporeal life support circuit

Fear of Self-Injecting and Self-Testing and the Related Risk Factors in Adolescents with Type 1 Diabetes: A Cross-Sectional Study

INTRODUCTION

This study was conducted to investigate the fear of self-injecting and self-testing and its related risk factors among adolescents with type 1 diabetes mellitus (T1DM).

METHODS

From December 2015 to April 2016, a cross-sectional study was performed at the Diabetes Treatment Center, Prince Sultan Military Medical City, Riyadh, Saudi Arabia on 142 registered T1DM patients between 13 and 19 years of age. Selection of the respondents was done deliberately and carefully, and the suitable patients were given specific identification numbers. A trained interviewer administered the short Diabetes Fear of Injecting and Self-testing Questionnaire to each patient. It included two subscales estimating the fear of self-injection (FSI) and fear of self-testing (FST). Each patient's age, gender, weight, height, adjusted body mass index (BMI), duration of the diabetic condition, treatment modality, insulin dosage, and glycosylated hemoglobin (HbA1c) were recorded.

RESULTS

The study found that the overall mean score of FSI was 2.44 ± 0.96, whereas that of FST was 2.25 ± 1.04. Adolescents above 16 years of age, treated with multiple daily insulin (MDI), on higher insulin doses, having poor glycemic control, and fewer finger pricks were observed to show significant risk factors for fear of self-injection of insulin, whereas in those patients having a long duration of T1DM, MDI treated, on higher insulin doses, with poor glycemic control, and fewer finger pricks showed significant risk factors for fear of self-testing of blood glucose. From the regression analysis it was evident that the variables of higher age, MDI treatment, and fewer finger pricks were independent risk factors for fear of self-injection of the insulin, whereas a fewer number of finger pricks was an independent risk factor for fear of self-testing the blood glucose.

CONCLUSION

Fear of self-injecting and fear of self-testing are common among adolescents with T1DM. Therefore, it is essential to ensure comprehensive multidisciplinary diabetes education to lower the risk factor of fear of injections.

The artificial pancreas: evaluating risk of hypoglycaemia following errors that can be expected with prolonged at-home use

AIMS

Artificial pancreas systems show benefit in closely monitored at-home studies, but may not have sufficient power to assess safety during infrequent, but expected, system or user errors. The aim of this study was to assess the safety of an artificial pancreas system emulating the β-cell when the glucose value used for control is improperly calibrated and participants forget to administer pre-meal insulin boluses.

METHODS

Artificial pancreas control was performed in a clinic research centre on three separate occasions each lasting from 10 p.m. to 2 p.m. Sensor glucose values normally used for artificial pancreas control were replaced with scaled blood glucose values calculated to be 20% lower than, equal to or 33% higher than the true blood glucose. Safe control was defined as blood glucose between 3.9 and 8.3 mmol/l.

RESULTS

Artificial pancreas control resulted in fasting scaled blood glucose values not different from target (6.67 mmol/l) at any scaling factor. Meal control with scaled blood glucose 33% higher than blood glucose resulted in supplemental carbohydrate to prevent hypoglycaemia in four of six participants during breakfast, and one participant during the night. In all instances, scaled blood glucose reported blood glucose as safe.

CONCLUSIONS

Outpatient trials evaluating artificial pancreas performance based on sensor glucose may not detect hypoglycaemia when sensor glucose reads higher than blood glucose. Because these errors are expected to occur, in-hospital artificial pancreas studies using supplemental carbohydrate in anticipation of hypoglycaemia, which allow safety to be assessed in a controlled non-significant environment should be considered as an alternative. Inpatient studies provide a definitive alternative to model-based computer simulations and can be conducted in parallel with closely monitored outpatient artificial pancreas studies used to assess benefit.

Feasibility and precision of subcutaneous continuous glucose monitoring in patients undergoing CABG surgery

OBJECTIVES

To evaluate if subcutaneous continuous glucose monitoring (sCGM) is feasible in cardiac surgery and if reliable glucose values are reported under hypothermic extracorporeal circulation.

DESIGN

Feasibility trial.

SETTING

University hospital.

PARTICIPANTS

Ten consecutive patients undergoing coronary artery bypass grafting.

INTERVENTIONS

Prior to surgery, during hypothermic extracorporeal bypass, and 48 hours postoperatively, arterial blood glucose samples were compared with sCGM every 30 minutes. Statistical analysis utilized Clarke's error grid and Bland-Altman plot.

MEASUREMENTS AND MAIN RESULTS

Three hundred fifty-one pairs of glucose measurements were recorded including 59 during hypothermic extracorporeal circulation. Agreement between these measurements was acceptable, with a regression line slope of 0.88 and an offset of 17.4 (p = 0.87). Error grid analysis indicated a safe margin of 99.1% within zone A (no clinical action needed) or zone B (values would not lead to inappropriate treatment). Only 0.9% were plotted in zone D (potentially dangerous failure). Measurements during hypothermic extracorporeal circulation were comparable. Correlation coefficient was 0.760. The offset regression line was more pronounced (50.9) with a flatter slope (0.640). Within the error grid all plot values were in zone A or B.

CONCLUSIONS

sCGM compared with arterial blood gas glucose monitoring under hypothermic extracorporeal circulation appears to be feasible and reliable.

Hypoglycemia in critically ill children

BACKGROUND

The practice of glycemic control with intravenous insulin in critically ill patients has brought clinical focus on understanding the effects of hypoglycemia, especially in children. Very little is published on the impact of hypoglycemia in this population. We aimed to review the existing literature on hypoglycemia in critically ill neonates and children.

METHODS

We performed a systematic review of the literature up to August 2011 using PubMed, Ovid MEDLINE and ISI Web of Science using the search terms "hypoglycemia or hypoglyc*" and "critical care or intensive care or critical illness". Articles were limited to "all child (0-18 years old)" and "English".

RESULTS

A total of 513 articles were identified and 132 were included for review. Hypoglycemia is a significant concern among pediatric and neonatal intensivists. Its definition is complicated by the use of a biochemical measure (i.e., blood glucose) for a pathophysiologic problem (i.e., neuroglycopenia). Based on associated outcomes, we suggest defining hypoglycemia as <40-45 mg/dl in neonates and <60-65 mg/dl in children. Below the suggested threshold values, hypoglycemia is associated with worse neurological outcomes, increased intensive care unit stay, and increased mortality. Disruptions in carbohydrate metabolism increase the risk of hypoglycemia incritically ill children. Prevention of hypoglycemia, especially in the setting of intravenous insulin use, will be best accomplished by the combination of accurate measuring techniques, frequent or continuous glucose monitoring, and computerized insulin titration protocols.

CONCLUSION

Studies on hypoglycemia in critically ill children have focused on spontaneous hypoglycemia. With the current practice of maintaining blood glucose within a narrow range with intravenous insulin, the risk factors and outcomes associated with insulin-induced hypoglycemia should be rigorously studied to prevent hypoglycemia and potentially improve outcomes of critically ill children.

Value of continuous glucose monitoring for minimizing severe hypoglycemia during tight glycemic control

OBJECTIVE

Tight glycemic control can potentially reduce morbidity and mortality in the intensive care unit but increases the risk of hypoglycemia. The most effective means to avoid hypoglycemia is to obtain frequent blood glucose samples, but this increases the burden to nursing staff. The objective of this study was to assess the ability of a real-time continuous glucose monitor to reduce hypoglycemia (blood glucose <60 mg/dL [3.3 mmol/L]) during standard care or tight glycemic control effected with a proportional integral derivative insulin titration algorithm.

DESIGN

Real-time continuous glucose monitor profiles obtained from an ongoing prospective randomized trial of tight glycemic control were retrospectively analyzed to determine whether the continuous glucose measure had prevented instances of hypoglycemia.

SETTING

Cardiac intensive care unit.

PATIENTS

Children 3 yrs of age or younger undergoing cardiac surgery were studied.

INTERVENTIONS

Intravenous insulin infusion and rescue glucose guided by the real-time continuous glucose monitor and the proportional integral derivative algorithm in the tight glycemic control arm (n = 155; target glucose 80-110 mg/dL [4.4-6.1 mmol/L]) and the real-time continuous glucose monitor in the standard care arm (n = 156).

MEASUREMENTS AND MAIN RESULTS

No reduction in hypoglycemia was observed with real-time continuous glucose monitor alarms set at 60 mg/dL (3.3 mmol/L) (zero of 19 occurrences of blood glucose <60 mg/dL [3.3 mmol/L] detected); 18 of 40 subsequent incidences of hypoglycemia were detected after the alarm threshold was increased to 70 mg/dL (3.9 mmol/L). In the tight glycemic control arm, eight incidences were reduced in duration and an additional eight events were prevented with intravenous glucose. In the standard care arm, three of nine occurrences of hypoglycemia were detected with the duration reduced in all cases. On average, one to two false hypoglycemia alarms were observed in each patient.

CONCLUSIONS

The real-time continuous glucose monitor in combination with proportional integral derivative control can reduce hypoglycemia during tight glycemic control. The real-time continuous glucose monitor can also reduce hypoglycemia during standard care. However, false alarms increase the overall nursing workload.