Developing Novel Neuromonitoring for Neuroprotection in Congenital Heart Disease

Dr. Lynch (left) is leading several high-impact translational research initiatives advancing the use of biomedical optics for children with CHD. Shown with lab members Alyssa Seeney, Nicolina Ranieri.

By Nancy McCann

Abnormalities that occur in a baby's heart as the heart is developing during pregnancy affect approximately 40,000 infants born in the United States each year — making congenital heart disease (CHD) the most common birth defect.

During the last half-century, tremendous strides have been made in the cardiac care of these children as surgical advancements have improved survival. In the 1960s mortality was nearly 100%, but today it's below 10%. However, neurodevelopmental disabilities remain a significant morbidity among survivors.

"Now that these children are surviving infancy, we are noticing problems in their neurologic outcomes," said Jennifer Lynch, MD, PhD. "When these kids reach school age, they have a higher chance of neurodevelopmental disabilities than children without congenital heart disease."

But with Dr. Lynch's innovative research to advance neuromonitoring to detect periods of neurologic risk in CHD, she aims to improve these outcomes. As a pediatric cardiac anesthesiologist and physicist specializing in biomedical optics at Children's Hospital of Philadelphia, Dr. Lynch's research centers on building a noninvasive optical neuromonitoring research device for use in cardiac operating rooms, catheterization labs, and critical care units for improved neuromonitoring in this vulnerable patient population.

"Individualizing care is important for the outcomes of our patients, and the use of this research device may help to improve neuroprotection by matching care to the individual needs of each child," Dr. Lynch said. "Our quest is to make a real impact in pediatric cardiac care, one optical innovation at a time."

Lynch Lab for Novel Biomedical Optics: Studying the When and How of Neurological Injury

From left to right: Clinical Research Manager Alyssa Seeney, PI Jennifer Lynch, and Bioengineering doctorate student Nicolina Ranieri setting up the optical neuromonitoring device for a clinical measurement.

Dr. Lynch has been walking the campus paths and halls of CHOP and University of Pennsylvania since 2009, when she was a graduate student at Penn studying physics and working in the Research Institute in the Wolfson Family Laboratory as a collaborator developing an optical monitoring device. She went on to get her doctorate in physics, a medical degree, and clinical training — all while keeping her research projects going at the Research Institute. She currently has dual appointments in anesthesiology and bioengineering at Penn, splitting her time evenly between research and clinical responsibilities.

After her long training path that provided unique interdisciplinary expertise, she is thrilled to now lead several high-impact translational research initiatives advancing the use of biomedical optics for children with CHD.

"Improving outcomes in these children requires a better understanding of the underlying injury mechanisms and the development of methods that can provide earlier diagnosis of a neurologic injury," Dr. Lynch said.

The Lynch Lab for Novel Biomedical Optics is trying to determine when and how this injury is occurring in these children. Their innovative approach revolves around building a novel device, for research purposes, that uses light to measure cerebral oxygen delivery and utilization. This device is not used clinically — yet. But evidence of its clinical utility for children with CHD is mounting, and Dr. Lynch is at the forefront of this research.

"My lab focuses on bringing this tool into this very vulnerable time period of infant heart surgery to pinpoint when brain injury is occurring so we can change clinical management to prevent injury from happening," Dr. Lynch said.

Their research covers a wide range of areas, from studying the period after birth when infants with critical CHD are awaiting life-saving procedures to improving neurologic outcomes during neonatal cardiac surgeries. They envision, in the not-so-distant future, having a monitor present during the cardiac surgery for a child with CHD that provides much more information about how the brain is getting oxygen and how it's utilizing oxygen than what is currently used — near-infrared spectroscopy.

By using their research device, the Lynch Lab discovered that the longer time between birth and cardiac surgery increases the risk of brain injury for children with CHD because the oxygenation in their brains was decreasing every day they waited for surgery.

"This is all very novel, and it's changed how we think about these children in terms of scheduling their surgery," Dr. Lynch said. "These novel neuromonitoring tools have helped us understand that earlier surgery may be neuroprotective in certain patients."

Studying Use of Neuromonitoring in Delivery Room

Dr. Lynch’s body of work aims to show, through different patient populations within this congenital heart community, how this optical neuromonitoring device can be used to improve care. Dr. Lynch shown here with Bioengineering doctorate student Nicolina Ranieri.

When a child is born with CHD, much happens in trying to care for the baby's heart to make sure everything is OK from a cardiac perspective. Dr. Lynch's team is bringing this instrument into the delivery room to study what happens from a neurologic perspective. Preliminary data shows that potentially some of the ways doctors help to protect patients' hearts may not provide neuroprotection.

"For instance, we sometimes intubate babies to improve oxygenation, but by intubating and taking over their breathing, it changes the blood flow to the brain," Dr. Lynch said. "We need improved neuromonitors during this vulnerable time period to make sure we are not causing more harm than good in terms of oxygen delivery to the brain."

The Lynch Lab is also investigating the neurologic impact of procedures like device closure of patent ductus arteriosus in premature babies and collaborating with other researchers in biomedical optics to monitor intracranial pressure in patients with single-ventricle physiology and measure tissue water content in patients with lymphatic abnormalities.

Her body of work aims to show, through different patient populations within this congenital heart community, how this device can be used to improve care.

As Dr. Lynch continues to build her team, the Lynch Lab is part of a vibrant biomedical optics research community at CHOP including the Optical Neuroimaging Lab led by Brian White, MD, PhD, and the Wolfson Family Laboratory for Clinical and Biomedical Optics now led by Wesley Baker, PhD. CHOP research scientists Tiffany Ko, PhD, and Rodrigo Forti, PhD, are also collaborators. Together they combine cutting-edge technology with clinical experience to find practical solutions for better neuromonitoring and improved neurologic outcomes in children with heart conditions. The three labs share resources, research assistants, and graduate students, and collaborate on studies and papers.