Hypoglycaemia in infants studied
19 June 2012
Researchers from the University of Canterbury’s Bioengineering Mechatronics Programme are part of a large, collaborative project looking at the development of young children who were at risk of hypoglycaemia, or low blood sugar, in their early neonatal period.
Director of the UC Mechatronics Programme, Professor Geoff Chase, says UC researchers are involved in the project because of their expertise with hypoglycaemia through the management of patients with high blood sugar at both the adult ICU at Christchurch Hospital and in extremely pre-term infants at Christchurch Women’s NICU, as well as expertise in managing complex data and signals.
"We model the major human physiological systems – the metabolic system, the cardio-vascular system and pulmonary mechanics. We then use these models, with data in clinic, to provide better monitoring of something that cannot be measured directly with ease, or in diagnostics, or to guide treatment,” he says.
The multi-disciplinary study, called CHYLD (Children with Hypoglycaemia and their Later Development), is based at The University of Auckland, led by Distinguished Professor Jane Harding from the Liggins Institute.
It was Professor Chase’s team that, several years ago, developed the Specialised Relative Insulin Nutrition Table (SPRINT), a laminated wheel-based system to control blood glucose levels and nutritional intakes in intensive care patients. Already proven to have saved 50 lives a year and $1m/year in costs at Christchurch Hospital, the system has now been improved and computerised.
“We are very familiar with the continuous glucose monitors (CGMs) that are used in this study,” says Professor Chase. “These are tiny sensors which, when inserted under the skin, can sense subcutaneous glucose. To remove the need for invasive testing which was previously done by pinstick, CGMs were used to measure blood sugar concentrations of the newborn babies in the study at Waikato Hospital.
“CGMs do need frequent calibration however, and can produce significant random noise. The way you calibrate the devices can change the data produced, and thus the results, so how this is done and the way that subsequent data is managed is something that best leverages engineering skills.”
Hypoglycaemia in neonatal infants can cause brain damage, but currently it is not known which babies will be affected or what levels of blood sugar might trigger the damage.
The CHYLD study investigates the development of children from two neonatal studies. The first, BABIES, observed 100 newborns from the NICU at Waikato Hospital between December 2006 and February 2009. The second, Sugar Babies, recruited 514 babies between November 2008 and November 2010.
All of these babies had continuous monitoring of their blood sugar concentrations in the first few days after birth, which clearly showed that there was more hypoglycemia than had been previously observed using non-continuous, invasive testing.
CHYLD is assessing the childrens’ mental and physical development, memory, vision and general health at both 2 and 4.5 years of age, and aims to relate this to the hypoglycaemia experienced as newborns. The duration, severity or frequency of these periods may all be of relevance in the overall conclusions, and the UC team will be assisting with data analysis of these factors.
The study has been funded over five years by the US National Institutes of Health and NZ Health Research Council, and will provide critical knowledge on how best to monitor and treat newborn babies to prevent brain damage and the long-term associated consequences.
For more information please contact:
Professor Geoff Chase
University of Canterbury
(03) 364 2987 ext 7224
021 342 743