Hemodynamic effects of intrathecal sufentanil compared with epidural bupivacaine in laboring parturients

Abstract

Study objectives: To provide information on the central hemodynamic effects of intrathecal sufentanil after a standard intravenous preload using thoracic bioimpedance monitoring to obtain noninvasive measurements of cardiac index (CI), stroke index (SI), and systemic vascular resistance (SVR). To compare hemodynamic parameters after intrathecal sufentanil labor analgesia to those after a standard dose of epidural bupivacaine in laboring parturients.

Design: Randomized, double-blind study.

Setting: Labor and delivery unit in a university hospital.

Study design: 40 ASA status I parturients were randomized into two groups receiving analgesia with combined spinal-epidural technique. Group SUF received 10 micrograms of intrathecal sufentanil followed by 12 ml of saline through an epidural catheter; Group BUP received 2 ml of intrathecal saline followed by 12 ml of 0.25% epidural bupivacaine. Heart rate (HR), blood pressure (BP), and thoracic bioimpedance monitoring were recorded. Pain scores, fetal HR, and side effects were noted.

Measurements and main results: No significant changes from baseline were seen in CI, SI, or SVR index. Mean arterial pressure was lower in Group BUP at 10 and 20 minutes after induction of analgesia. Mean HR was lower in Group SUF at 20 and 30 minutes after induction. Two patients in Group SUF and four patients in Group BUP experienced hypotension requiring ephedrine. Pain scores were lower in Group SUF at 10 minutes after induction of analgesia; subsequent pain scores and duration of analgesia were similar. Fourteen patients in Group SUF experienced itching.

Conclusions: No significant differences in CI, SI, or SVR index were seen after either method of analgesia. A few patients in both groups experienced hypotension requiring treatment with ephedrine. Both techniques of labor analgesia appear to provide effective pain relief but care must be taken with either method to monitor maternal BP.