Comparison of epidural tramadol-ropivacaine and fentanyl-ropivacaine for labor analgesia: A prospective randomized study

BACKGROUND To test the hypothesis that 5 mg/mL tramadol is superior to 3 ?g/mL fentanyl when combined with 0.125% ropivacaine in parturients undergoing labor during epidural analgesia. METHODS Sixty-one parturients undergoing labor selected for delivery with epidural analgesia were randomized into two groups: Group tramadol (0.125% ropivacaine plus tramadol 5 mg/mL) and Group fentanyl (0.125% ropivacaine plus fentanyl 3 ug/mL). Hemodynamics, rate of cesarean delivery, sensory block level, Bromage motor scale scores, instrument-assisted delivery, oxytocin use, visual analog scale (VAS) scores, Apgar scores, umbilical cord artery gas analysis, and maternal side-effects including nausea, vomiting, pruritus, urinary retention, shivering, hypotension, and respiratory depression were recorded. RESULTS The two groups had no significant differences with respect to maternal hemodynamics, neonatal heart rate, VAS scores, rate of cesarean delivery, sensory block level, Bromage motor scale scores, instrument-assisted delivery, oxytocin use, hypotension, nausea, vomiting, and respiratory depression (p > 0.05). The incidence of pruritus, shivering, and urinary retention were more commonly observed in Group fentanyl despite there was no significant difference between the two groups. Umbilical artery pH was significantly lower while PCO(2) was higher in Group fentanyl than Group tramadol (p = 0.003 and p = 0.026, respectively). Birth-weight, umbilical artery PO(2) and base deficit, and Apgar scores at 1 and 5 min were comparable between the two groups (p > 0.05). CONCLUSIONS Our observations suggest that tramadol seems to be a safe alternative to fentanyl for labor analgesia due to its similar analgesic efficacy.