This Pacifier Could Monitor Babies’ Vitals in the NICU

Hong Yeo, associate professor and Harris Saunders Jr. Endowed Professor in the George W. Woodruff School of Mechanical Engineering, came up with the pacifier idea at a pediatric technology conference.

A small but powerful invention could make life in the NICU easier for the tiniest patients.

Newborns must have their vitals checked frequently, and one of the most critical measures of newborn health is electrolyte levels. Right now, the only way to monitor electrolytes is to draw their blood multiple times a day. This can be painful and frightening for babies, and challenging to perform for medical staff, who can have trouble drawing blood from tiny, underdeveloped blood vessels.

Now, researchers at the Georgia Institute of Technology have developed a pacifier designed to monitor a baby’s electrolyte levels in real time, potentially eliminating the need for repeated invasive blood draws.

Hong Yeo, associate professor and Harris Saunders Jr. Endowed Professor in the George W. Woodruff School of Mechanical Engineering, came up with the pacifier idea at a pediatric technology conference. Doctors described daily challenges they face in caring for sick newborns, and the lack of noninvasive monitoring systems.

Hojoong Kim (left), a research professor at the WISH Center and program manager of the KIAT-Georgia Tech Semiconductor Electronics Center, developed special electronic circuits specifically for the pacifier device.

“Physicians told me about the blood draw issue, which happens over and over again as babies sometimes have to stay in the NICU for weeks and even months,” said Yeo, who directs the Wearable Intelligent Systems and Healthcare Center (WISH Center) at the Institute for Matter and Systems.

“I wanted to come up with a noninvasive solution for constant electrolyte monitoring, and I decided to focus on something babies like: pacifiers. I immediately thought, ‘OK, I can do something with that.’”

Yeo purchased a few commercially available pacifiers and started brainstorming potential designs. He realized that if he and his team could figure out how to collect a baby’s saliva with the pacifier, then they would likely be able to attach flexible membrane sensors using his existing miniaturization technologies.

The team constructed a tiny tunnel, or microfluidic channel, into the body of the pacifier. The opening at the pacifier’s nipple draws saliva into the channel, which then guides the saliva through the device and into a reservoir equipped with ion-detecting sensors. The sensors react to sodium and potassium ions, constantly measuring their levels.

The pacifier device is made of several key components, including flexible sensors, thin-film circuits, and a wafer for making microfluidic channels.

Hojoong Kim, a research professor at the WISH Center and program manager of the KIAT-Georgia Tech Semiconductor Electronics Center (which Yeo directs), developed special electronic circuits specifically for the pacifier device.

“To make the pacifier wireless, we designed an ultrathin, membrane-based electronic circuit,” Kim said. “We used our technology to make the circuit extremely thin and floppy, so it is flexible and soft in a way that it can be mounted to almost any surface.”

The team installed their flexible circuit on the back side of the pacifier. There, they integrated all the circuit’s wireless components to be compatible with conventional Bluetooth. The system sends the data wirelessly, so physicians can use a smartphone or tablet to receive a real-time, continuous flow of data about a baby’s vitals at any given moment.

This constant data flow paints a fuller picture of babies’ health, and it means serious issues can be detected sooner. If any abnormal signs arise during monitoring, the system alerts the clinicians or medical staff who are using the device.

Hojoong Kim examines the team's wireless pacifier prototype.

According to Yeo, the team continually works to develop and optimize the pacifier technology. Currently, the team is seeking funding and commercialization partners that can help take the technology to the next level and into the world.

“Once we get it into hospitals, I think the device will be a game-changer for pediatric health monitoring,” Yeo said. “As far as I know, this is the only device in the world that can measure a baby’s electrolyte concentrations continuously.”

The researchers also think the technology can be expanded further to benefit additional patient populations. The concept of using saliva as a noninvasive way of measuring important disease biomarkers can be greatly expanded, Yeo says.

“This is an important step in showing that this technology can work, and this is just the beginning,” Yeo said. “We hope to integrate the technology with other electrical sensors and systems to achieve comprehensive health monitoring that wasn’t possible until now.”

Note: Soonmin Lee (clinician at Yonsei Medicine), Hyo-Ryoung Lim (former postdoctoral fellow), and Musa Mahmood (former Ph.D. student) also played a major role in developing this technology.

Funding: National Science Foundation Research Traineeship program, WISH Center (Institute for Matter and Systems), and K-GTSEC Center.