Aiming to Avoid the Scalpel
The Unkindest Cut
The normal oxygen saturation for a fetus is usually between 30%
and 70%, Simpson says. A lack of oxygen for an extended period of time can
result in hypoxia, brain damage, or even death.
With the oxygen monitor, Schuler was able to avoid the scalpel
and vaginally deliver a healthy baby girl.
"It was kind of scary, because in five minutes they had me
numbed up and the operating room ready to go," Schuler says. "But it
turned out the baby was fine, which was great because no one wants to get a
C-section if you don't have to."
The percentage of C-sections recently has been rising after a
steady decline from 1989 to 1995. About 22% of live births in 1999 were
delivered by C-section, a 4% increase from 1998, the CDC reports. What's more,
the rehospitalization rate after C-sections was 80% compared to the 30% of
those rehospitalized following an uncomplicated vaginal birth. In general,
women who undergo C-sections risk infections of the uterus or around the
incision, as well as urinary and gallbladder complications.
Of the 6,800 babies born annually at St. John's, about 23% are
delivered by C-section. Simpson says she is hopeful that the oxygen monitor
will reduce that.
A clinical study of more than 1,000 births at nine sites
nationwide suggested that fetal oxygen monitors, when used in conjunction with
heart rate monitors, could halve the number of C-sections related to a
"nonreassuring" heart rate. But the study, published in the November
2000 issue of the American Journal of Obstetrics and Gynecology, also
found an increase in the overall number of cesarean deliveries due to dystocia
-- failure of the baby to pass through the pelvis. The company that makes the
monitors and which funded the study, St. Louis-based Mallinckrodt Inc., is
paying for further research to determine what effect the monitors might be
having, if any, on women who encounter such difficulties. "It's a very
puzzling finding from the study," says Garite, a co-author of the study.
"We are doing a follow-up, multicenter study to look at the
Researchers also are examining whether the oxygen monitors
could be useful in evaluating premature infants, Garite says. Currently, the
monitor is employed only in women dilated past two centimeters whose water has
broken after a fetal heart monitor shows an abnormal rate. Women who are
carrying more than one fetus, who are less than 36 weeks pregnant, or who are
carrying a breech baby cannot use the device.
Mallinckrodt declined to disclose the number of hospitals using
OxiFirst, but says more and more are adopting the system. At the time of FDA
approval, the fetal oxygen monitor had been relied on in more than 35,000
births. The technology has been available in Europe since 1996 and in Canada