NIRS - Near-Infrared Spectroscopy

Premature twins benefit from innovative blood-oxygen monitoring


Jessica Graham was six months pregnant with her sons, Charlie and Beckett, when something suddenly didn't feel quite right. It was early evening and, after a prenatal appointment that day, she was relaxing on the couch.

"At first I thought maybe it was gas pains," Jessica said. "Having had a baby before, I knew what labor felt like, and it wasn't like this."

The odd feeling crept into her lower back, a rhythmic ache that, though mild, remained persistent. When she was still wide awake at 10:30 p.m., Jessica called her obstetrician. Her doctor suggested a warm shower and that Jessica start timing the frequency of the sensation.

"I took the shower," Jessica said. "And that's when everything started happening."

The sensation suddenly strengthened into pains that were so close together, Jessica realized she might be in labor. Her husband, Jason Graham,rushed her to Cedars-Sinai. The resident in the E.R. examined Jessica and promptly sent her upstairs to the maternity ward.

"My doctor got there 20 minutes later, and I was 7 centimeters dilated," Jessica said. "It was awful, it was too soon, the babies were too little, and there was no way it was all going to be just fine."

Charlie and Beckett Graham, who were delivered via C-section at about 4 a.m., weighed less than two pounds each. They were among the estimated 12 percent of infants in the U.S. who are born pre-term. Among all births, both term and pre-term, an estimated 10 to 15 percent of infants will require care in a NICU.

Though Charlie and Beckett spent the first four months of their lives in the NICU, things did in fact turn out fine for the tiny infants. The fraternal twins celebrated their first birthday Oct. 20. The happy outcome was due to the boys themselves, to the skill of the Cedars-Sinai team, and to the innovative use of NIRS, a noninvasive way to monitor blood oxygen levels that, until recently, has been used mainly in adults.

"The babies might have had to undergo monitoring that was more invasive and less specific if not for the innovative approach used in our NICU," said Charles F. Simmons Jr., MD, chair of the Department of Pediatrics and director of the Division of Neonatology at Cedars-Sinai's Maxine Dunitz Children's Health Center."Our overall approach to newborn care at Cedars-Sinai is to make the care at the bedside individual and personalized, and this is an example of that."

A NIRS (Near-Infrared Spectroscopy) monitor uses light at the near-infrared spectrum to measure oxygen levels beneath multiple sensors, which are placed like Band-Aids on a baby's skin. NIRS monitoring is unique in that it provides doctors with a non-invasive estimate of oxygen saturation in blood after it has passed through the capillaries and into the veins. For decades doctors have been monitoring arterial oxygen saturation using light through the use of conventional pulse oximeters, but measuring the veinous oxygen saturation was not possible non-invasively. To do so would require drawing blood from a vein via a painful needle stick, often once per hour. Unlike the spectroscopy method, which gives continual readouts from multiple organs in an infant's body, the needle-stick method yields limited and delayed information at the cost of painful procedures and blood loss.

"It all comes down to supply and demand," said Willliam Binder MD., a neonatologist at Cedars-Sinai. "The old conventional arterial pulse-ox monitor's told us about the oxygen supply, but we didn't know what the tissues were doing with it. The NIRS monitor completes the picture. Now we know the oxygen demand from the organs and tissues, and that tells us so much more about what the body needs, and with that information we can make adjustments to optimize the oxygen delivery to the tissues. Previously we were in the dark with regard to this. The NIRS is like having night-vision goggles."

The NIRS method gives minute-to-minute oxygenation assessments that no other technology can provide," Simmons said. "With it, we have the ability predict and react to changes that are otherwise unforeseen and unpredictable."

Oxygen-related complications in infants can include brain damage, heart damage, kidney failure, shock and seizures.

With his twin sons attached to so many machines and monitoring devices, Jason Graham said he and Jessica were grateful for anything that would ease the burden on the babies.

"They were checking Charlie and Beckett's blood gasses ever hour, which means they would have been pricking their toes," Jason said. "I was open to any kind of innovation that would help them, and maybe help someone else."

Jessica agrees.

"These poor kids have scars, these tiny white dots you can still see, from being poked and prodded and from trying to find veins for blood draws and IVs and medicines," she said. "As far as I was concerned, anything that could be done to make it less painful, I wanted that."