Comparison of three different doses of intrathecal fentanyl and sufentanil for labor analgesia

Study Objective: To compare the duration of analgesia and incidence of side effects of three doses of intrathecal fentanyl (25 μg, 37.5 μg, 50 μg) with three doses of intrathecal sufentanil (5 μg, 10 μg, 15 μg). Design: Randomized, double-blind study. Setting: Labor suite of the Hospital of the University of Pennsylvania. Patients: 60 ASA physical status I and II parturients in active labor who requested analgesia. Interventions: Patients received one of the six doses of opioid diluted with normal saline to achieve a volume of 1.5 ml intrathecally. Measurements and Main Results: Duration of analgesia, contraction pain, degree of pruritus, maternal blood pressure, maternal heart rate, fetal heart rate, Apgar scores, and neurologic and adaptive capacity scores were measured. There was no statistical difference among the doses of fentanyl in duration of analgesia. In addition, there was no statistical difference among the doses of sufentanil. The durations of analgesia for all doses of sufentanil were statistically longer than that for all doses of fentanyl. There was no difference among all the groups for maximal pruritus score. The duration of pruritus did not differ among doses of fentanyl or sufentanil; the duration of pruritus was significantly longer for sufentanil. All groups had a decrease in blood pressure. There was no difference among the groups in regard to the effect on the systolic or diastolic blood pressure. Conclusions: Intrathecal sufentanil analgesia of longer duration than fentanyl for all doses studied. The duration of pruritus with sufentanil was also longer.