Comparison of Intrathecal Injection of Fentanyl and Sufentanil on the Onset, Duration, and Quality of Analgesia in Labor: A Randomized, Double-Blind Clinical Trial

BACKGROUND: Labor pain is a severe pain, and intrathecal opioid injection is one of the analgesia methods to reduce it. OBJECTIVES: We assessed the effects of intrathecal Fentanyl and Sufentanil on the onset, duration, and quality of analgesia for labor analgesia. METHODS: In this double-blind, randomized clinical trial, 54 healthy nulliparous women 18 - 45 years in the active phase of labor who were requesting labor analgesia were enrolled in two groups fentanyl (F) and sufentanil (S). Patients received 75 µg fentanyl or 7.5 µg sufentanil intrathecally in the fentanyl group (n = 27) and the sufentanil group (n = 27), respectively. Pain relief, onset, duration of analgesia, hemodynamic parameters, patients' satisfaction, and neonatal Apgar score were assessed in this study. Data were analyzed by using SPSS16. RESULTS: There were no significant differences between the groups in terms of demographic and hemodynamic parameters. The onset time of analgesia was 5.6 ± 4.3 and 3.6 ± 2.1 minutes, in the sufentanil and fentanyl groups, respectively (P = 0.037). The duration of analgesia was higher in patients who received sufentanil than those who received fentanyl (113 ± 45 vs. 103 ± 22 minutes (P = 0.629)). The pain score in the Fentanyl group was significantly lower at 5, 10, and 15 minutes after spinal analgesia (P < 0.05). The sedation score at 1 and 5 minutes was significantly higher in the fentanyl group than the sufentanil group (P < 0.05). The frequency and severity of pruritus and satisfaction rate in the fentanyl group were significantly higher than the sufentanil group. CONCLUSIONS: Intrathecal fentanyl and sufentanil have a similar analgesic effect on labor. Fentanyl is associated with a faster onset of analgesia and more satisfaction, while sufentanil has longer analgesia.