Subarachnoid fentanyl with diluted small-dose bupivacaine for cesarean section delivery

The use of neuraxial opioid was very popular in recent years, and they may augment the analgesia produced by local anesthetic through direct binding with the spinal opioid receptors. Hemodynamic stability is very important during Cesarean section. Theoretically, the reduction of local anesthetic by addition of fentanyl would provide better hemodynamic stability and good anesthetic status.

Thirty healthy parturients undergoing Cesarean section were assessed in a randomized fashion. They were divided into two groups. Each subject received 5 mg hyperbaric bupivacaine plus 25 micrograms fentanyl (0.5 ml) and cerebrospinal fluid (CSF) 0.6 ml (Group M + F) or 8 mg hyperbaric bupivacaine plus 0.5 ml of CSF (Group M). The effects of hemodynamic stability, side effects, and complete analgesic duration were observed.

It was disclosed that the hemodynamic status was more stable in group M + F. The incidence of nausea and vomiting appeared to be not statistically significant between groups. The incidence of pruritus was apparently higher in group M + F (93.5% vs. 0) but the incidence of shivering was much lower in group M + F (0 vs. 33.3%). The complete analgesic duration was longer in group M + F (146 +/- 47 min vs. 104 +/- 44 min). There were no significant differences in the anesthetic and surgical status, 1-min and 5-min Apgar scores, and the time of regression of sensory level to T10.

The combination of small-dose bupivacaine with fentanyl could provide more stable hemodynamic status, longer postoperative analgesia, and lower incidence of shivering. The incidence of pruritus in group M + F was high, but it was usually mild.