Comparison of Spinal Versus Epidural Analgesia for Vaginal Delivery: A Randomized Double Blinded Clinical Trial

BACKGROUND: Recently, one of the problems in developing countries is pregnant women who insist on cesarean section for fear of painful vaginal delivery. There are various methods to reduce labor pain, including medical and non-medical methods. Neuraxial analgesia is classified as one of the best ways to reduce labor pain. Epidural analgesia is a classic and popular procedure to decrease labor pain. Nevertheless, other methods, such as spinal or combined spinal-epidural analgesia, is more effective compared with the epidural. OBJECTIVES: In this study, we investigated a single intrathecal versus epidural injection in pregnant women during childbirth. METHODS: In our research, after obtaining informed consent, the patients were randomly assigned to two equal groups: epidural and spinal. Each group contained 50 parturient women in advanced labor. In the epidural group, 2.5 mL isobaric bupivacaine 0.5%, sufentanil (0.2 mcg/mL), and 7 mL saline 0.9% were injected by an 18-gauge Tuohy needle at the L4-5 or L5-S1 intervertebral space, and in the spinal group, 0.5 mL isobaric bupivacaine 0.5%, 2.5 mcg sufentanil, and 0.5 mL saline 0.9% were injected by a 25-gauge pencil-point Quincke needle at the L4-5 or L5-S1 intervertebral spaces. For pain intensity, the visual analog scale (VAS) was used at serial intervals, and other variables, such as the onset and duration of analgesia, hypotension, neonatal APGAR score, fetal heart rate (FHR) changes, and other variables were examined. RESULTS: The mean time to onset analgesic effect was 4.6 min in the spinal group compared with 12.5 minutes in the epidural (P < 0.001). Duration of analgesia was 121 minutes in the spinal group compared with 104 min in the epidural group (P < 0.001). The time to reach the maximum block was 8.4 min in the spinal group vs. 22.2 min in the epidural group (P < 0.001). The duration of the second and third gestation stages was the same in both groups. CONCLUSIONS: Spinal analgesia is short and easy to perform and does not require advanced equipment and technical experience. Spinal analgesia can be a good option for labor analgesia and leads to achieving a lower pain score than epidural analgesia.