It’s every new parent’s nightmare that, after the birth of their new baby, their child is too unwell to receive standard care treatment and instead needs additional support. In some cases, these children are not well enough to leave hospital and head home, as would be expected following the majority of births. In the UK, more than 100,000 babies are cared for in neonatal units annually – about one in seven, according to the charity Bliss. In the US, half a million babies are born prematurely, meaning they are at greater risk of needing support in the days after birth.

For families facing this challenging time, leaving their baby in hospital when they return home is often the dilemma, and heartache, they are faced with. However, thanks to a new device it is hoped fewer families will face that ordeal. A team of researchers at the Worcester Polytechnic Institute (WPI) in Massachusetts is working on a miniaturised sensor that will measure a baby’s blood oxygen levels. About the size of a regular plaster, the wireless, flexible and stretchable remote device will be able to monitor a baby’s condition and report any concerning developments to the hospital where the patient is, and the baby’s parents or carers.

“Two parameters of oxygenation, oxygen saturation and oxygen concentration, are extracted from the blood sample,” explains Ulkuhan Guler, assistant professor of electrical and computer engineering, director of WPI’s Integrated Circuits and Systems Lab and research lead. “Pulse oximeter is a surrogate method of measuring blood oxygen saturation noninvasively. Since it has extensive usage, currently, it also became a surrogate method of assessing the blood oxygen concentration, which is a risk since these two are different parameters and have a different significance.”

From small beginnings

After beginning her career with WPI, Guler received a start-up fund for her research, from which she has funded the work she is doing into this miniaturised oxygen sensor.

Measuring blood gases diffusing through the skin, the device monitors the baby’s oxygen levels to determine how effective the lungs are in maintaining the required level of oxygen around the body to ensure bodily tissues are receiving an adequate amount. Oxygen levels in the blood are a vital sign of how efficient the lungs are working, giving physicians an insight into the development and overall well-being of a child – potentially highlighting problems in asymptomatic patients.

The research has the potential to dramatically change the way babies, and their families, are cared for in the future. “While there are various non-invasive device types, ranging from wearables to benchtop – bedside, hospital use – devices, available for monitoring blood saturation, the variety of devices that can monitor blood oxygen concentration is limited, and these are mainly expensive bulky benchtop devices,” says Guler. “Our device measures the blood oxygen concentration non-invasively from the oxygen molecules that are diffusing through our skin.”

The device is the first of its kind, miniaturised and wearable. Before now, transcutaneous oxygen-monitoring devices have used a heating mechanism that significantly reduces the feasibility of these devices, partly due to the size they have needed to be. “Our device uses optical sensors and works by measuring blood oxygen levels non-invasively,” says Guler. “The light intensity of the sensor changes with the concentration of oxygen on the skin.”

“While there are various non-invasive device types available for monitoring blood saturation, the variety of devices that can monitor blood oxygen concentration is limited, and these are mainly expensive bulky benchtop devices.”

After joining WPI in August 2018, Guler set out to speak with doctors to understand what their real needs were, with a focus on those not being met. “I did this because I believe that this is a way that will create an impact, a real difference,” Guler says.

These conversations led her to the device she’s currently working on. One particular exchange with the University of Massachusetts’ Lawrence Rhein, part of the research team, stands out. “He listed the types of devices that would be very beneficial to have in neonatal intensive care units, or that could be used to monitor babies while they are at home,” explains Guler. “Not only were the type of the devices, but possible body parameters or biosignals that we can extract non-invasively discussed in that meeting.”

A wide range of benefits

Not only extremely costly, extended stays in hospitals may even have a detrimental impact on a baby’s ability to develop. Being able to have an infant cared for and monitored in the home environment is always the ultimate goal, something Guler believes could be possible with her innovation.

“This device offers a significant contribution to patient monitoring from home by providing rapid and continuous measurement of the vital sign of blood oxygenation,” says Guler. “The measured data will be collected and analysed by a companion app and transmitted to a secure server for storage and sharing with physicians.”

That data can then be processed, making it ‘readable’ for physicians, who will then use the information to influence their treatment plans, and for caregivers who will be informed about the status of their infant.

“It will be connected to the internet wirelessly, so an alarm on a monitor in a doctor’s office or smartphone app would notify medical personnel and family members if the baby’s oxygen level begins to drop,” explains Guler. “Continuous and remote tracking of vital respiratory parameters in a fully wireless manner will provide relevant and accurate data to the caregiver to inform the course of treatment in an outpatient setting.”

It has benefits in more traditional care settings too. Thanks to its weight and size, babies can be more easily examined by the teams who are treating them, and even held by loved ones.

Its potential is not restricted to infants either, Guler believes that older patients suffering from conditions such as asthma and chronic obstructive pulmonary disease might also benefit. It’s an avenue she intends to explore in future research. In light of the significance of these findings, Guler is now looking to secure additional funding to take the development of the device further.

Final stages of development

Currently the three prototypes developed are powered by a battery that lasts for more than three weeks, with the current power consumption requirement of the system. However, Guler and her team are now working on creating the next prototype that will have wireless powering functionality.

The final product will be a novel, non-invasive, wireless, flexible wearable, which will perform continuous monitoring of blood gas content diffused through the skin. It will measure the partial oxygen levels (PO2) providing a more accurate reading than simple oxygen saturation measurements. It can then send the collected information remotely to a secure cloud service for both medical professionals and patients to use. Furthermore, future medical research will be enabled with aggregated long-term massive data, something that was not available previously.

The next stage of development involves working with the University of Massachusetts Medical School to conduct a small-scale human trial in a cohort of premature and term infants, as well as adults. Guler has big hopes for this research. “Achieving a successful implementation of newly developed technology on this fragile population will enable a smooth transfer of technology to other patient populations with respiratory-related diseases,” says Guler. Supported by a team at WPI, Guler believes the device will open the door for clinical studies to discover new treatments. This includes research on the cognitive and organ development of infants with the correlation of oxygen levels in the blood. Both current and future work in this area is hugely promising for parents wanting to take their babies home earlier than had previously been possible.

100,000

Babies are cared for in neonatal units in the UK, which is about one in seven.

Bliss

“It will be connected to the internet wirelessly, so an alarm on a monitor in a doctor’s offi ce or smartphone app would notify medical personnel and family members if the baby’s oxygen level begins to drop.”

“The ability to remotely monitor these at-risk babies could improve the feasibility of early discharge and reduce the risk of undiagnosed issues after hospital release,” says Guler. “Moreover, successful outpatient care will reduce the strain on medical resources, increase the outcomes of treatment and decrease the risk of readmittance.”


Ulkuhan Guler on the benefits of wireless oxygen sensors for newborns

Over a decade ago, a sick newborn lay in a neonatal intensive care unit in Istanbul. Years later, his hospital stay would inspire his mother, now an engineer at WPI, to create a miniaturised wireless oxygen sensor that would enable infants to leave the hospital and still be safely monitored from home.

“My son had just been born when they told me he had a respiratory problem and they put him in the NICU,” says Guler. “For three days, they let me see him only three times a day, for 15 minutes at a time. They had to disconnect all the monitor wires to be able to give him to me, but they needed to monitor his breathing – so I couldn’t hold him more than that. I wanted to be close to him. It was so frustrating.”

Guler’s son Musa, her oldest child, has grown into a healthy 11-year-old who’s interested in engineering and his mother’s stories of how he came into this world. His sister Bahar is seven; she too was ill as a baby. She was severely jaundiced but was treated as an outpatient. Because she didn’t need to be wired to monitors and her doctor realised the importance of skin-to-skin contact for newborns, she was allowed to go home with her mother and visit the hospital twice a day for treatment.

According to the National Institutes of Health, babies who don’t receive that magical touch cry more, are more stressed and have more trouble with cardiorespiratory stability, including oxygen saturation levels.

As her babies grew, Guler – still in Turkey – focused on the smart card security field while studying for her PhD. But when she arrived in the US, healthcare and biotechnology caught her attention.

“There was a lot of research being done and I thought I could be a part of that,” she says. “I could use my knowledge to contribute to this field and help people in a different way.”

At WPI in early 2018, Guler was introduced to Lawrence Rhein, chair of the department of [aediatrics and an associate professor at UMass Medical School. She wanted to know how she could put her engineering skills to work in the medical field.

“I asked him, ‘What do you need in the NICU but it doesn’t exist?’” she explained. “He gave me a list and I saw among the projects a need that reminded me of what our family had needed – a miniaturised, wireless oxygen sensor. Of course, I chose this project. It really increased my motivation. The project has research value and I knew that from my experience.”