The Effects of Temperature and Relative Humidity on Point-of-Care Glucose Measurements in Hospital Practice in a Tropical Clinical Setting

Using geographic rescue time contours, point-of-care strategies, and spatial care paths to prepare island communities for global warming, rising oceans, and weather disasters

OBJECTIVES

To perform geographic contour analysis of sea and land ambulance rescue times in an archipelago subject to super typhoons; to design point-of-care testing strategies for medical emergencies and weather disasters made more intense by global warming and rising oceans; and to assess needs for prehospital testing on spatial care paths that accelerate decision making, increase efficiency, improve outcomes, and enhance standards of care in island nations.

METHODS

We performed needs assessments, inspected healthcare facilities, and collected ambulance rescue times from professionals in the Bantayan Archipelago, Philippines. We mapped sea/land ambulance rescue routes and time contours. To reveal gaps, we statistically compared the fastest and slowest patient rescue times from islands/islets and barangays to the District Hospital on Bantayan Island. We developed spatial care paths (the fastest routes to care) for acute myocardial infarction, community care, and infectious diseases. We generated a compendium of prehospital diagnostic testing and integrated outcomes evidence, diagnostic needs, and public health goals to recommend point-of-care strategies that build geographic health resilience.

RESULTS

We observed limited access to COVID-19 assays, absence of blood gas/pH testing for critical care support, and spatial gaps in land and airborne rescues that worsened during inclement weather and sea swells. Mean paired differences (slowest-fastest) in ambulance rescue times to the District Hospital for both islands and barangays were significant (P < 0.0001). Spatial care path analysis showed where point-of-care cardiac troponin testing should be implemented for expedited care of acute myocardial infarction. Geospatial strengths comprised distributed primary care that can be facilitated by point-of-care testing, logical interisland transfers for which decision making and triage could be accelerated with onboard diagnostics, and healthcare networks amenable to medical advances in prehospital testing that accelerate treatment.

CONCLUSIONS

Point-of-care testing should be positioned upstream close to homes and island populations that have prolonged rescue time contours. Geospatially optimized point-of-need diagnostics and distributed prehospital testing have high potential to improve outcomes. These improvements will potentially decrease disparities in mortality among archipelago versus urban dwellers, help improve island public health, and enhance resilience for increasingly adverse and frequent climate change weather disasters that impact vulnerable coastal areas. [350 words].

Effects of Simulated Adverse Environmental Conditions Related to Actual Conditions at Health Promoting Hospitals on the Performance of Blood Glucose Testing by Glucose Meters

BACKGROUND

Annual peaks in temperature and humidity exceed manufacturers' specifications for blood glucose test strip storage in Thailand. Health Promoting Hospitals (HPH) do not always provide the same level of health services that hospitals do since they often only turn on air-conditioning units during working hours.

METHODS

The blood glucose testing performance of 4 glucose meters were investigated for short and long terms stress at 5 simulated conditions. Temperature and relative humidity (RH) at 5 HPHs in different regions of Thailand were monitored for 9 weeks during April to July 2019. The use of air conditioning in storage rooms for storing test strips was surveyed at 131 HPHs using questionnaires.

RESULTS

Median-paired differences of glucose measurements with stressed test strips in 5 simulated conditions significantly differed (P < 0.05) both in the short term (3 days) and in the long term (30 days) with 4 glucose meters when compared to unstressed test strips. The average temperature of all HPHs exceeded 30°C (86°F). The average RH was 84%. There was only one HPH that occasionally turned on its air conditioners. Most HPHs kept both opened and unopened vials of test strips in rooms without air conditioners. Further, 21.4-32.0% of HPHs kept test strips at room with air conditioners.

CONCLUSIONS

This study provides evidence for poor performance of blood glucose testing by glucose meters that are affected by adverse environmental conditions. The environmental for test strips storage at HPHs should be considered to prevent analytical errors of glucose measurement.

A review of temperature-related challenges and solutions for the Abbott i-STAT and Siemens Healthineers epoc devices

The Abbott i-STAT and Siemens Healthineers epoc are commonly used in the provision of care during emergency medical services calls and other settings. Maintaining these systems within manufacturer's temperature claims in these settings poses challenges across the world. This review summarizes solutions that have been reported in the peer-reviewed literature and proposes additional strategies to further address these challenges. A literature search was performed with Clarivate's Web of Science from inception to August 3, 2022. Search terms included i-STAT, epoc, temperature, cold, hot, heat, freeze, frozen, prehospital, disaster, POCT, point of care, blood gas, helicopter, airplane, and ambulance. One author also reviewed manually every issue of the Journal of Paramedic Practice. The search identified 17 solutions for addressing temperature-related challenges with the i-STAT device, nine solutions for i-STAT cartridges, one solution for the epoc device, and one solution for the epoc test card. The majority of solutions were highly portable and consisted of widely available, inexpensive components. The solutions demonstrated only partial or entirely questionable effectiveness in achieving temperature control. The search also identified five reports on the impact of storage temperatures on cartridges and test cards. The reports suggested that these reagents may be able to withstand storage at temperatures outside of manufacturer's claims with only minimal deterioration in performance. The heterogeneity of solutions and the paucity of evidence on their effectiveness suggest that additional strategies are needed to better understand and further address temperature-related challenges with these systems. A collaborative approach and shared decision making are recommended.

Clinical Study of a High Accuracy Green Design Blood Glucose Monitor Using an Innovative Optical Transmission Absorbance System

BACKGROUND

Blood glucose monitoring (BGM) is essential for glycemic control in diabetic therapy. Followingly, accurate sensors are required for both daily personal and clinical use. The frequency of sensor use in patients with diabetes facilitates the use of disposable components. However, BGM systems are not exempt from green innovation sustainability initiatives.

METHODS

Clinical study of a high-accuracy green design blood glucose monitor using an innovative optical transmission absorbance system was carried out. Venous blood samples were collected from 104 patients with type II diabetes. The heat resistance of sensor strips was evaluated by storing sensor strips at 25℃ and 60℃ for approximately 3 months. Accuracy of the BGM system was evaluated via the ISO 15197:2013 protocol.

RESULTS

The BGM system achieved ±7.1% accuracy in glycemic level measurement, with 84% of all measurements within ±5% of the reference values. Furthermore, the sensor strip demonstrated heat resistance for more than 3 months when stored at 60℃.

CONCLUSIONS

A new, highly accurate BGM system was developed based on the latest optical measurement system, introducing a rare metal-free "green-strip." The developed BGM system achieved the highest reported accuracy in clinical research, using venous blood from patients with diabetes. The sensor strip also exhibited high heat resistance, reducing limitations on storage conditions.

Development of semi-quantitative urinary sodium test strip

Excessive salt consumption has been associated with greater risk of hypertension. Therefore, monitoring of dietary sodium consumption should be prioritized. As sodium is mainly excreted through urine, 24-hours urine sample can be used to estimate individual sodium intake. Thus, a simple and inexpensive semi-quantitative urinary sodium detection test strip was developed based on the enzymatic reaction between β-galactosidase and chlorophenol red-β-D-galactopyranoside. When tested, colour formation was distinguished at 0 M (chartreuse yellow), 0.05 M (sunflower), 0.1-0.15 M (mango tango), and 0.2-0.25 M (persimmon) sodium. Analysis from ImageJ showed a linear result (r² >0.9), low SD, and significant increase in magenta difference (p<0.01) between 0 M and 0.05-0.25 M sodium. Test strip can detect 0.03 M sodium at minimum but did not last for >2 days in adverse storage conditions (laboratory conditions, ∼80% relative humidity, 40°C, and direct light exposure) when stored in test strip bottles, and even shorter when exposed to the environment. The presence of urinary potassium, urea, and glucose did not affect test strip performance. Test strip produced comparable results to flame photometry with <15% variation when tested on overnight, random spot, and 24-hours urine samples. Overall, the developed test strip can be used to enzymatically semi-quantify 0.05-0.25 M sodium. Test strip was developed by using β-galactosidase and chlorophenol red-β-D-galactopyranoside for the enzymatic detection of urinary sodium. Test strip could perform urinary sodium monitoring by providing colour indicator based on the concentration of sodium tested in the urine sample at a quicker timing in comparison to current quantification methods. The developed test strip could be used by hypertensive and normotensive users conveniently and repeatably wherever and whenever possible without additional equipment. This article is protected by copyright. All rights reserved.

Diagnostics and monitoring tools for noncommunicable diseases: a missing component in the global response

A key component of any health system is the capacity to accurately diagnose individuals. One of the six building blocks of a health system as defined by the World Health Organization (WHO) includes diagnostic tools. The WHO's Noncommunicable Disease Global Action Plan includes addressing the lack of diagnostics for noncommunicable diseases, through multi-stakeholder collaborations to develop new technologies that are affordable, safe, effective and quality controlled, and improving laboratory and diagnostic capacity and human resources. Many challenges exist beyond price and availability for the current tools included in the Package of Essential Noncommunicable Disease Interventions (PEN) for cardiovascular disease, diabetes and chronic respiratory diseases. These include temperature stability, adaptability to various settings (e.g. at high altitude), need for training in order to perform and interpret the test, the need for maintenance and calibration, and for Blood Glucose Meters non-compatible meters and test strips. To date the issues surrounding access to diagnostic and monitoring tools for noncommunicable diseases have not been addressed in much detail. The aim of this Commentary is to present the current landscape and challenges with regards to guidance from the WHO on diagnostic tools using the WHO REASSURED criteria, which define a set of key characteristics for diagnostic tests and tools. These criteria have been used for communicable diseases, but so far have not been used for noncommunicable diseases. Diagnostic tools have played an important role in addressing many communicable diseases, such as HIV, TB and neglected tropical diseases. Clearly more attention with regards to diagnostics for noncommunicable diseases as a key component of the health system is needed.

Neuroticism Modulates the Functional Connectivity From Amygdala to Frontal Networks in Females When Avoiding Emotional Negative Pictures

Amygdala activity was previously found to correlate with neuroticism as an effect of valence, but so far few studies have focused on motivational context. The network subserving altered amygdala activity has not yet been investigated although some studies showed strong effective connections with prefrontal cortex (PFC). The goal of this study was to test the modulatory role of neuroticism on the functional connectivity (FC) between amygdala and other brain regions, especially PFC, during emotion processing from motivational direction. We applied an emotional picture viewing paradigm with different motivational directions (approaching and avoiding) in a large participant sample. The results showed that neuroticism predicted the amount of amygdala FC to dorsomedial PFC (dmPFC) and middle cingulate cortex (MCC). Increased FC during negative vs. positive pictures was found primarily in low neuroticism subjects, especially during the avoid condition. This valence and motivation dependent connectivity increase were disrupted for high neurotic participants. No effect of neuroticism was found for the approach condition. We showed that neuroticism, especially in the context of passive affect regulation, may have impaired connectivity between amygdala and putative regulatory cortical networks.

PSoC-Stat: A single chip open source potentiostat based on a Programmable System on a Chip

In this paper we demonstrate a potentiostat built with a single commercially available integrated circuit (IC) that does not require any external electronic components to perform electrochemical experiments. This is done using the capabilities of the Programmable System on a Chip (PSoC®) by Cypress Semiconductor, which integrates all of the necessary electrical components. This is in contrast to other recent papers that have developed potentiostats but require technical skills or specialized equipment to produce. This eliminates the process of having to make a printed circuit board and soldering on electronic components. To control the device, a graphical user interface (GUI) was developed in the python programming language. Python is open source, with a style that makes it easy to read and write programs, making it an ideal choice for open source projects. As the developed device is open source and based on a PSoC, modification to implement other electrochemical techniques is straightforward and only requires modest programming skills, but no expensive equipment or difficult techniques. The potentiostat developed here adds to the growing amount of open source laboratory equipment. To demonstrate the PSoC potentiostat in a wide range of applications, we performed cyclic voltammetry (to measure vitamin C concentration in orange juice), amperometry (to measure glucose with a glucose strip), and stripping voltammetry experiments (to measure lead in water). The device was able to perform all experiments and could accurately measure Vitamin C, glucose, and lead.

Novelty seeking and reward dependence-related large-scale brain networks functional connectivity variation during salience expectancy

A salience network (SN) anchored in the anterior insula (AI) and dorsal anterior cingulate cortex (dACC) plays a key role in switching between brain networks during salience detection and attention regulation. Previous fMRI studies have associated expectancy behaviors and SN activation with novelty seeking (NS) and reward dependence (RD) personality traits. To address the question of how functional connectivity (FC) in the SN is modulated by internal (expectancy-related) salience assignment and different personality traits, 68 healthy participants performed a salience expectancy task using functional magnetic resonance imaging, and psychophysiological interaction analysis (PPI) was conducted to determine salience-related connectivity changes during these anticipation periods. Correlation was then evaluated between PPI and personality traits, assessed using the temperament and character inventory of 32 male participants. During high salience expectancy, SN-seed regions showed reduced FC to visual areas and parts of the default mode network, but increased FC to the central executive network. With increasing NS, participants showed significantly increasing disconnection between right AI and middle cingulate cortex when expecting high-salience pictures as compared to low-salience pictures, while increased RD also predicted decreased right dACC and caudate FC for high salience expectancy. Our findings suggest a direct link between personality traits and internal salience processing mediated by differential network integration of the SN. SN activity and coordination may therefore be moderated by novelty seeking and reward dependency personality traits, which are associated with risk of addiction. Hum Brain Mapp 38:4064-4077, 2017. © 2017 Wiley Periodicals, Inc.