Is epidural analgesia an effective way to manage pain during labor and what is the connection between it compared to instrumental delivery and caesarean section? Evgen Grizhymalskyi, the Head of the Anesthesiology and Intensive Care Department, is answering this question.
It is well-known that childbirth is a physiological process. At the same time, it is often accompanied by severe pain. Pain during labor is a subjective sensation caused by stretching of the lower uterine segment, cervical dilatation, pressure on the pelvic floor and perineal muscles, stretching of the vulvar ring and perineal skin.
Epidural analgesia (EA) is most commonly used to relieve and control pain in women in labor. The Cochrane Database of Systematic Reviews found epidural anesthesia to be the most effective pain management technique compared to inhalation anesthesia, systemic opioid and non-opioid analgesics, and non-pharmacological agents .
Since today EA has become widely used in medical practice to relieve labor pains, disputes have occasionally arisen between doctors about a direct connection between epidural anesthesia, instrumental delivery and caesarean section.
We (the team of Leleka Maternity Hospital) are also interested in this topic. Therefore, we would like to share an interesting original research of our Lithuanian colleagues, which was conducted in 2015 and published in the international medical journal MEDICINA titled “Labor epidural analgesia and the incidence of instrumental assisted delivery” by Kęstutis Rimaitis, as well as our data on this issue.
Based on the findings of the retrospective case-control study, the purpose of which was to study the effects of epidural analgesia on labor and its connection with the instrumental delivery, the following conclusions were drawn. Patients who underwent instrumental assistance (women in labor who underwent epidural anesthesia and instrumental delivery), as well as women in labor who did not have EA but underwent instrumental delivery were studied. Demographic data, main characteristics of pregnancy and childbirth, and short-term neonatal outcomes in newborns were examined.
Findings of the study
During the study period, 7,675 women underwent vaginal deliveries and 187 patients underwent instrumental delivery (2.43 %). Vacuum extractions were applied to 67 women in labor (2.16 %) who received EA, and to 120 women in labor (2.61 %) who did not receive EA. On average, the duration of the first stage of labor was 510 minutes in the group of women with EA (for comparison, this stage was up to 390 minutes in the control group without EA but with instrumental delivery) — (P = 0.001). The average duration of the second stage of labor was from 40 to 60 minutes, respectively, P < 0.0005. Oxytocin was used much more often during childbirth to enhance the contractile activity of the uterus with poor uterine contraction strength (in 80.3 % of cases) compared to 58.3 % of cases in the control group (P = 0.003). There was no significant interrelation between the use of epidural anesthesia and instrumental delivery.
Advantages and disadvantages of the study
The authors of this article consider it important to mention several disadvantages of this study. First, any retrospective study is inevitably associated with a selection bias since women who experience labor pains and are more likely to have surgical intervention during childbirth ask for EA more often than others. This category of women belongs to a large risk group. Therefore, EA is recommended for them. Moreover, the use of oxytocin during labor pains has not been documented in women who received EA. Since oxytocin enhances the uterine contractile activity with poor uterine contraction strength, it can also affect the overall process of labor. Secondly, most of the studied women who received EA had not given birth before (in 81.8 % of cases compared to 18.2 % of cases). This may have influenced the total duration of labor, as well as the duration of certain stages of labor. A subgroup analysis of primiparas and multiparas who received EA showed that the first stage of labor was much longer in primiparas, while the duration of labor did not increase much in multiparas compared to primiparas.
Conclusions based on the study findings
According to this study, the use of epidural analgesia does not affect the likelihood of instrumental delivery and the risk of negative neonatal outcomes. At the same time, EA is directly related to the duration of the first and second stages of labor.