Screen all newborns for secret heart defects as routine – researchers
Published 05/08/2011 | 07:53
All newborn babies should be routinely screened for life-threatening heart defects using a simple and painless test, researchers said today.
The pulse oximetry test measures blood oxygen levels in newborns by means of a small skin sensor placed on the hands or feet.
A major British study published today showed it can identify babies with congenital heart defects who would otherwise be missed by doctors.
Many of these infants would under normal circumstances go on to develop serious complications or die.
Identifying the problems early on allows doctors to correct or reduce them with surgery, where possible, or plan medication treatments.
Heart defects present from birth are one of the leading causes of infant death in the developed world and affect one in 145 newborn babies in the UK.
Examples include hypoplasia, or underdevelopment of part of the heart, obstructions that block blood flow, valve defects and hole-in-the-heart conditions that allow blood to leak from one side of the heart to the other.
Current techniques for identifying babies with a congenital heart defect involve ultrasound scans and routine physical examinations shortly after birth.
However these methods are far from foolproof and many affected babies leave hospital undiagnosed.
The new study, the largest of its kind ever undertaken in the UK, tested the accuracy of pulse oximetry on more than 20,000 babies born at six maternity units across the West Midlands.
In all cases the babies appeared to be healthy at birth.
The tests, conducted between February 2008 and January 2009, detected 53 cases of major congenital heart disease, 24 of which were critical.
In 35 cases, congenital heart defects were already suspected after ultrasound examinations. But 18 cases identified by pulse oximetry had not been picked up by ultrasound.
The test was able to spot three quarters of all critical cases. When it was combined with ultrasound and physical examination, the detection rate of critical heart abnormalities rose to 92% and no babies died from undiagnosed problems.
The findings were published today in an online edition of The Lancet medical journal.
Describing the test, lead investigator Dr Andrew Ewer, from the University of Birmingham, said: "It's usually performed within 24 hours of birth and is simple, painless and non-invasive.
"A small probe is put on the baby's hand and then on the foot, the machine is switched on and you obtain a reading. That's it. It takes longer to undress the baby than it does to do the test."
He added: "This study has shown conclusively that this test is advantageous. We would like to see all babies being routinely tested. In this way the test will pick up additional babies who might otherwise have become very ill or even died.
"I think we now have enough evidence to say that pulse oximetry screening should be incorporated into everyday clinical practice."
The test also flagged up other non-heart related problems such as respiratory disorders and infections.
Amy Thompson, senior cardiac nurse at the British Heart Foundation, said: "We know that congenital heart disease affects around one in every 145 births and, although great progress has been made in the treatment and care of congenital heart disease, early and rapid detection is key for greater survival.
"Not all babies who are born with a heart defect will show any signs or symptoms, so problems can go unnoticed. This is a promising piece of research which shows how a quick and simple test could help to detect more heart defects and make a real difference."
Two American experts commenting on the research in The Lancet backed the test while sounding a note of caution.
Dr William Mahle, from Emory University School of Medicine in Atlanta, Georgia, and Dr Robert Koppel, from Cohen Children's Medical Centre in New York, wrote: "The decision to introduce another screening assay (test) for newborn babies is one that should be made after careful consideration. Health care systems in the developed world are already heavily burdened. Yet the compelling data provided by Ewer and colleagues support inclusion of pulse oximetry into the care of the newborn baby