G D Ogle1,2, M Abdullah3, D Mason4,5, A S Januszewski6, S Besançon7. 1. International Diabetes Federation Life for a Child Program, Sydney, NSW, Australia. grahamo@diabetesnsw.com.au. 2. Diabetes NSW, Glebe, NSW, Australia. grahamo@diabetesnsw.com.au. 3. Sudan Childhood Diabetes Centre, Khartoum, Sudan. 4. International Diabetes Federation Life for a Child Program, Sydney, NSW, Australia. 5. Macquarie University, Sydney, NSW, Australia. 6. NHMRC Clinical Trials Centre, University of Sydney, Sydney, NSW, Australia. 7. Santé Diabète, Bamako, Mali.
Abstract
AIM: Insulin loses potency when stored at high temperatures. Various clay pots part-filled with water, and other evaporative cooling devices, are used in less-resourced countries when home refrigeration is unavailable. This study examined the cooling efficacy of such devices. METHODS: Thirteen devices used in Sudan, Ethiopia, Tanzania, Mali, India, Pakistan and Haiti (10 clay pots, a goat skin, a vegetable gourd and a bucket filled with wet sand), and two identical commercially manufactured cooling wallets were compared. Devices were maintained according to local instructions. Internal and ambient temperature and ambient humidity were measured by electronic loggers every 5 min in Khartoum (88 h), and, for the two Malian pots, in Bamako (84 h). Cooling efficacy was assessed by average absolute temperature difference (internal vs. ambient), and % maximal possible evaporative cooling (allowing for humidity). RESULTS: During the study period, mean ambient temperature and humidity were 31.0°C and 32.0% in Khartoum and 32.9°C and 39.8% in Bamako. All devices reduced the temperature (P < 0.001) with a mean (sd) reduction from 2.7 ± 0.5°C to 8.3 ± 1.0°C, depending on the device. When expressed as % maximal cooling, device efficacy ranged from 20.5% to 71.3%. On cluster analysis, the most efficacious devices were the goat skin, two clay pots (from Ethiopia and Sudan) and the suspended cooling wallet. CONCLUSIONS: Low-cost devices used in less-resourced countries reduce storage temperatures. With more efficacious devices, average temperatures at or close to standard room temperature (20-25°C) can be achieved, even in hot climates. All devices are more efficacious at lower humidity. Further studies are needed on insulin stability to determine when these devices are necessary.
AIM: Insulin loses potency when stored at high temperatures. Various clay pots part-filled with water, and other evaporative cooling devices, are used in less-resourced countries when home refrigeration is unavailable. This study examined the cooling efficacy of such devices. METHODS: Thirteen devices used in Sudan, Ethiopia, Tanzania, Mali, India, Pakistan and Haiti (10 clay pots, a goat skin, a vegetable gourd and a bucket filled with wet sand), and two identical commercially manufactured cooling wallets were compared. Devices were maintained according to local instructions. Internal and ambient temperature and ambient humidity were measured by electronic loggers every 5 min in Khartoum (88 h), and, for the two Malian pots, in Bamako (84 h). Cooling efficacy was assessed by average absolute temperature difference (internal vs. ambient), and % maximal possible evaporative cooling (allowing for humidity). RESULTS: During the study period, mean ambient temperature and humidity were 31.0°C and 32.0% in Khartoum and 32.9°C and 39.8% in Bamako. All devices reduced the temperature (P < 0.001) with a mean (sd) reduction from 2.7 ± 0.5°C to 8.3 ± 1.0°C, depending on the device. When expressed as % maximal cooling, device efficacy ranged from 20.5% to 71.3%. On cluster analysis, the most efficacious devices were the goat skin, two clay pots (from Ethiopia and Sudan) and the suspended cooling wallet. CONCLUSIONS: Low-cost devices used in less-resourced countries reduce storage temperatures. With more efficacious devices, average temperatures at or close to standard room temperature (20-25°C) can be achieved, even in hot climates. All devices are more efficacious at lower humidity. Further studies are needed on insulin stability to determine when these devices are necessary.
Authors: Santiago Correa; Abigail K Grosskopf; Hector Lopez Hernandez; Doreen Chan; Anthony C Yu; Lyndsay M Stapleton; Eric A Appel Journal: Chem Rev Date: 2021-05-03 Impact factor: 60.622
Authors: Tomader Ali Mohammed Ibrahim; Denira Govender; Mohamed Ahmed Abdullah; Janelle Annette Noble; Mohammed Osman Hussien; Julie Ann Lane; Steven John Mack; Gregory George Noble Martin; Mark Alvin Atkinson; Clive Henry Wasserfall; Graham David Ogle Journal: Pediatr Diabetes Date: 2021-04-20 Impact factor: 3.409
Authors: Éimhín Mary Ansbro; Michel Biringanine; Grazia Caleo; David Prieto-Merino; Zia Sadique; Pablo Perel; Kiran Jobanputra; Bayard Roberts Journal: BMJ Open Date: 2019-11-24 Impact factor: 2.692