THE ADDITION OF BUPIVACAINE TO INTRATHECAL SUFENTANIL FOR LABOR ANALGESIA

We designed a prospective, randomized, double-blind study to evaluate the efficacy of the combination of intrathecal sufentanil with a low dose of local anesthetic in an attempt to prolong analgesia in labor. Fifty-two patients received one of the following intrathecal study solutions: 2.5 mg of bupivacaine; 10 mu g of sufentanil; or 2.5 mg of bupivacaine plus 10 mu g of sufentanil. The mean duration of analgesia (min +/- SD) was significantly different among all three groups: 70 +/- 34 min for bupivacaine, 114 +/- 26 min for sufentanil, and 148 +/- 27 min for bupivacaine-sufentanil (P < 0.001). Visual analog scale (VAS) scores for pain were significantly higher in the bupivacaine group compared to both the sufentanil group and the bupivacaine-sufentanil group (P < 0.02), and were significantly higher in the sufentanil group compared to bupivacaine-sufentanil at 75 min postinjection and beyond (P < 0.02). Hypotension was not observed in the sufentanil group but occurred transiently in the other two groups (P = 0.09). There was no evidence of motor blockade, excessive somnolence, fetal heart rate (FHR) abnormalities, or postdural puncture headache (PDPH) in any of the patients. The addition of 2.5 mg of bupivacaine to 10 mu g of intrathecal sufentanil significantly prolonged labor analgesia without adverse maternal or fetal effects.