- Epidural Analgesia is a mix of anesthetics and narcotics delivered by catheter place close to the nerves of the spine and is the most effective method of labor pain relief In widespread use since the 1970s, epidurals have long been thought to slow the second stage of labor -- defined as beginning when the cervix is completely dilated and ending when the baby is delivered. Because a longer duration of this stage of labor is associated with adverse outcomes, obstetricians routinely reduce or discontinue epidural pain management in an effort to expedite this main stage of labor.
via PHS Medical EPD (epidural positioning device)
When they reached the second stage of labor, participants were randomized to receive either the active anesthetic (low doses of the drugs ropivacaine and sufentanil) or the saline placebo. In this stage of labor, none of the mothers, investigators, obstetricians or midwives knew whether the catheter-delivered infusions containing the active pain medication or the saline placebo in this double-blind clinical trial.
|"We found that exchanging the epidural anesthetic with a saline placebo made no difference in the duration of the second stage of labor," said senior author Philip E. Hess, MD, Director of Obstetric Anesthesia at BIDMC and Associate Professor of Anaesthesia and of Obstetrics at Harvard Medical School. "Not even the pain scores were statistically different between groups. However, pain scores in women receiving the saline placebo increased over time, as would be expected."
Women in excessive pain were given unblinded doses of the active pain medication at their doctors' discretion and doctors could also terminate epidural infusions at any time based on clinical indicators.
The primary outcome, the duration of the second stage of labor, was similar between both groups: about 52 minutes for women given active pain medication versus about 51 minutes for women given the saline - just a 3.3 percent difference. The median times were also similar: 45 minutes for women on active pain medication versus 46 for those on saline. Of note, obstetricians requested to stop epidural infusions in 38 patients for poor progression of labor. Of these, 17 of the women were in the saline group. Twenty-one were in the active medication group.
"Twice as many women given the placebo reported lower satisfaction with their pain relief compared to those provided the anesthetic," said Hess. "Ethically, if epidural medications result in a negative effect on the second stage of labor, one could argue that a mild increase in maternal pain could be balanced by a successful vaginal delivery. We didn't see any negative effects, but epidural analgesia in the second stage of labor remains controversial and merits follow up studies."
In addition to Hess, study authors include, first author XiaoFeng Shen, MD; ShiQin Xu, MD; Nan Wang, MD; Sheng Fan, MD; Xiang Qin, RN; and Chunxiu Zhou, RN, of the Departments of Anesthesiology and Obstetrics and Gynecology, Nanjing Maternity and Child Health Care Hospital, Nanjing Medical University, Nanjing, Jiangsu, China; and Yunping Li, MD, of BIDMC.