BackgroundCurrently, there is no consensus on the optimal dose of fentanyl that should be combined with bupivacaine in spinal anesthesia for cesarean section deliveries.ObjectiveTo determine the optimal dose of intrathecal fentanyl to be combined with bupivacaine that is needed to obtain an optimal mix of sensory and motor block, analgesia, and acceptable incidence of adverse effects in spinal anesthesia for cesarean section deliveries.MethodsA prospective, randomized, double-blind clinical trial that was conducted in adherence to the Consolidated Standards of Reporting Trials (CONSORT) guidelines. Women who opted for elective cesarean section deliveries were randomized into 4 groups. Groups 1-3 received 7.5 mg of 0.5% hyperbaric bupivacaine with 10, 15, and 25 μg of fentanyl, respectively. Group 4 received 10 mg of 0.5% hyperbaric bupivacaine without fentanyl. Sensory and motor block, analgesia, hemodynamic stability, the incidence of adverse effects, and neonatal health outcomes were assessed.ResultsA total of 160 women completed the study (40 women in each group). The women who received 25 μg of fentanyl with 7.5 mg of 0.5% hyperbaric bupivacaine had significantly shorter (p-value < 0.0001) sensory block latency, longer duration of sensory block, longer duration of analgesia, less need for rescue analgesia, expressed higher satisfaction with analgesia, experienced less hemodynamic instabilities, and experienced fewer episodes of bradycardia and vomiting compared to those who received bupivacaine alone or in combination with lower doses of fentanyl. On the other hand, more episodes of pruritus were reported when bupivacaine was combined with fentanyl compared to bupivacaine alone (p-value < 0.01).ConclusionsThe combination of 25 µg intrathecal fentanyl with 7.5 mg of 0.5% hyperbaric bupivacaine in spinal anesthesia for cesarean section was associated with a favorable balance of sensory blockade, motor blockade, analgesia, and adverse effects. However, the increased incidence of pruritus should be considered.
Alkaissi et al. (Tue,) studied this question.