NEW YORK (Reuters Health) - The number of U.S. women who die from anesthesia complications during childbirth has fallen sharply in recent decades. But deaths specifically related to so-called regional anesthesia, which includes epidurals and spinal blocks, have crept upward since the mid-1990s, a new study finds.
Researchers stress that such deaths remain rare. But they also say the results point to an area where anesthesia can be made safer for women.
Regional anesthesia numbs the lower portion of the body and allows women to stay awake during childbirth. Most cesarean sections are done under regional anesthesia, but emergency C-sections often require general anesthesia.
Regional anesthesia is considered quite safe. But in rare cases, patients can have a severe allergic reaction to the anesthetic, or the drug can cause breathing or heart problems.
In the new study, researchers found that between 1979 and 2002, childbirth deaths related to any anesthesia complication dropped by 59 percent among U.S. women.
There were three such deaths for every million live births between 1979 and 1990, compared with just over one death per million births between 1991 and 2002 -- the most recent year for which data were available -- the researchers report in the journal Obstetrics & Gynecology.
However, while deaths related to general anesthesia kept falling in the 1990s, those related to regional anesthesia rose slightly, from 2.5 deaths for every million C-sections between 1991 and 1996 to 3.8 per million between 1997 and 2002.
“It is concerning,” said lead researcher Dr. Joy L. Hawkins, of the University of Colorado School of Medicine in Aurora.
She stressed that women should remember that anesthesia-related deaths during childbirth are a rare event. But there are steps that women can take themselves to minimize any risks.
“I think the main thing is to get good prenatal care, and keep any medical conditions you have under control during pregnancy,” Hawkins said in an interview.
That’s because chronic health conditions, like high blood pressure and diabetes, can make women more vulnerable to childbirth complications in general.
Hawkins also suggested that women make sure their anesthesiologist knows about any health conditions they have or medications they have been taking.
For their study, Hawkins and her colleagues used a U.S. government database that collects information on pregnancy-related deaths nationwide. Between 1991 and 2002, the system received 56 reports of anesthesia-related deaths during childbirth.
Most of the women who died - 48 of the 56 -- had undergone a C-section. In the rest of the cases, the type of delivery was not reported.
Deaths related to general anesthesia during C-section declined markedly over the decade. From 1991 to 1996, there were 17 such deaths per one million C-sections; that rate fell to 6.5 per million for the years 1997 to 2002.
In contrast, deaths related to regional anesthesia during C-section inched up.
The reasons for the increase are not known. According to Hawkins, the overall drop in anesthesia-related deaths since the 1970s is likely related to factors like safer drugs, better monitoring of women’s heart rates, blood pressure and oxygen while under anesthesia, and an improved understanding of how individuals can react to anesthesia.
But, she speculated, the medical profession may have become too narrowly focused on preventing deaths related to general anesthesia, which typically is more risky.
Research in the 1970s and 80s, Hawkins said, showed that pregnant women were 17 times more likely to die from general anesthesia than regional. And people reacted to that.
“A good part of our energy was tunnel-visioned toward general anesthesia,” Hawkins said. “Maybe we’ve let the pendulum swing a bit in the other direction.”
It is hard to study the potential reasons for the increase in deaths linked to regional anesthesia, precisely because they are so rare, Hawkins said. But information from malpractice claims suggests that a number of deaths in recent years were related to a lack of emergency resuscitation equipment in the delivery room.
So it’s possible, according to Hawkins, that having such equipment nearby could make a difference.
Obstetrics & Gynecology, online December 20, 2010.