FREDERICTON – In the last decade or so, many hospitals across North America have adopted a procedure to delay the clamping of the umbilical cord by a minute or two after birth because studies have shown it’s better for the baby’s health.
A couple of years, ago, Dr. Yu Chen of the Department of Laboratory Medicine at the Dr. Everett Chalmers Hospital in Fredericton was approached by Dr. Sheri-Lee Samson of the hospital’s Department of Obstetrics and Gynecology. Dr. Samson wanted to make Delayed Cord Clamping (DCC) standard procedure at the Chalmers.
“Normally the standard of care is once the baby is delivered, the obstetricians would clamp the umbilical cord immediately and then cut it,” said Dr. Chen, Chief and Medical Director of Laboratory Medicine at the Chalmers.
“A lot of evidence has accumulated saying that if that cord clamping can be delayed by one to two minutes, then the newborn baby can get an additional 80 – 100 millilitres of blood from the placenta, which normally would be wasted. By getting more blood, the baby has been found to have less chance of anaemia and less chance of infection. It’s a more rigorous baby.”
The Chalmers would be one of the first hospitals in Atlantic Canada to adopt this procedure, even though it had already gained widespread acceptance with many medical governing bodies, including the Society of Gynaecologists and Obstetrics of Canada (SOGC), the American Academy of Pediatrics, The American College of Gynecologists and Obstetrics (ACOG), and the World Health Organization (WHO).
The Chalmers’ medical teams wanted to settle an unresolved issue before they adopted the practice, however. The laboratory doctors do what’s called a “cord blood gas” test to evaluate the baby’s health at birth. But no one had conducted a definitive study on the potential differences in the results in the blood tests if the cord is clamped later rather than right away.
“They all recommend the [DCC procedure] but none of them had a clear indication for the impact of this procedure on the cord blood gas test measurements,” said Dr. Chen.
So Dr. Chen pulled a team together that included the Chalmers’ departments of Laboratory Medicine, and Obstetrics and Gynecology; the Faculty of Science at the University of New Brunswick; and the departments of Obstetrics and Gynecology, and Pathology at Dalhousie University.
The team would ultimately collaborate on a study that included nearly 500 patients (380 of who underwent the procedure where the cord was clamped immediately and 114 where the clamping was delayed for up to two minutes).
“If the doctor wants to delay the cord clamping by one to two minutes, it would be possible to change the blood gas test values – oxygen partial pressure, carbon dioxide partial pressure, and pH values,” said Dr. Chen. “[If that were the case] the reference ranges would need to be adjusted … you would need two sets of reference values [for the procedures] because immediate cord clamping is still needed for cases involving complicated births.”
They went ahead with the trial and tracked the results for a year and a half with the 494 participating women. Dr. Chen had a medical laboratory technologist (Rachel Fullarton) collected blood gas testing data, and an undergraduate science student (James Tang) from UNB to help tabulate the results and do the statistical analysis. It was the biggest study to date and it concluded that there was no need to craft a new set of reference values for the blood gas tests after the DCC procedure.
“There’s no significant difference between the delayed cord clamping and the old standard of care, immediate [clamping],” said Dr. Chen. “We found that with both obstetricians and laboratories, they can do this procedure and don’t have to set up two sets of reference ranges.”
Dr. Chen and his team have published a paper on their study in the international journal, Archive of Gynaecology and Obstetrics. And the New Brunswick Health Research Foundation (NBHRF) has named them Researchers of the Month for January.
It was very gratifying work for Dr. Chen, who recognizes the benefits of the DCC procedure for the health of newborns.
“We were able to solve a problem,” he said. “It was a happy collaboration.”
This story was sponsored by the New Brunswick Health Research Foundation.