Non-invasive optical sensors for the monitoring of cerebral oxygenation and detection of Hypoxic Ischaemic Encephalopathy (HIE) in neonates
Professor A. Petros, Great Ormond Street Hospital for Children
There is a need for a more reliable, non-invasive and alternative measurement site for the monitoring of arterial blood oxygen saturation in critically ill neonates when there is the risk of cerebral hypoxia (lack of oxygen reaching the brain). Currently pulse oximeters are devices used for the measurements of arterial blood oxygen saturation in neonates. In this technology the sensors are placed on the finger or toe. When the neonates become critically ill the circulation of blood at these sites becomes compromised as the blood is used to preserve more critical organs such as the lungs the liver and the brain. Therefore, pulse oximeters fail to measure oxygen levels at these difficulties times. Also, when babies suffer from Hypoxic Ischaemic Encephalopathy (HIE), a condition in which the brain does not receive enough oxygen, there is no readily available technology to detect such deficiency of oxygen in the brain. HIE can be fatal, within as little as five minutes of oxygen deprivation, brain cells can begin dying. The disease can also cause long-term damage, including intellectual disability, delayed development, seizures, and cerebral palsy.
To overcome the above limitations, the anterior fontanelle (AF) is proposed as a potential measurement site on the hypothesis that blood circulation may well be better preserved at this central site. The fontanelles commonly referred to as the “soft-spots” on the new-born baby’s head, are features that allow the skull to flex during labour so that the baby can pass through the birth canal. There is no bone present at these sites, only a thin membrane which makes it an ideal optical window for measurements of oxygen saturation directly from the brain. New novel optical non-invasive sensors will be custom made for this anatomical part and will be rigorously investigated in clinical trials.