Light Screens for Heart Disease in Newborns
DURHAM, N.C., Sept. 7, 2011 — A screening technique helps identify congenital heart disease in newborn babies by using various wavelengths of light to measure blood oxygen levels. Levels that are too low are a warning sign and trigger further investigation, say physicians at Duke University Medical Center, who recommend the screening.
Called pulse oximetry, this noninvasive and painless screening process will offer early detection in otherwise seemingly normal-appearing babies, said Duke’s Alex Kemper, one of the study’s authors.
Pulse oximetry uses light at different wavelengths that passes painlessly through the patient's skin and then measured by a detector to determine the percentage of oxygen-bound blood. A low level can result from congenital heart disease (CHD), certain infections, or other serious health problems.
CHD is responsible for more deaths in the first year of life than any other birth defect, but often outcomes can be improved with early detection. About one in every 120 babies is born with CHD, of which about 25 percent are critical, requiring special care early in life.
“One of the biggest challenges in implementing screening will be the follow-up after a positive screen,” Kemper said.
Many of the identified babies will require an echocardiogram or an evaluation by a pediatric cardiologist before they can go home. Because not all hospitals have these services, some babies may need to be transferred to another facility.
“Therefore, it is very important to avoid false positive screening results,” said Kemper. “We believe that the strategy we have developed will identify most cases but also have a false positive rate of less than one percent.”
The group's recommendations are based on large studies conducted in the US and Europe, but there are still many unanswered questions about how best to screen, including timing and the standards for a positive screen. For example, the algorithm's usual cutoff point for oxygen saturation may need to be adjusted for babies in high-altitude nurseries, where blood oxygen levels may normally be slightly lower.
The report was endorsed by the American Academy of Pediatrics, the American College of Cardiology Foundation and the American Heart Association.
On Aug. 31, based on evidence that has already been gathered, the state of New Jersey began initiating critical CHD screening for all babies before discharge.
“This will be a great opportunity for other states to learn how to begin screening on a wide scale,” Kemper said.
The study was published in the journal Pediatrics.
For more information, visit: www.duke.edu
- Electromagnetic radiation detectable by the eye, ranging in wavelength from about 400 to 750 nm. In photonic applications light can be considered to cover the nonvisible portion of the spectrum which includes the ultraviolet and the infrared.
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