Intrathecal epinephrine in combined spinal-epidural analgesia for labor: dose-response relationship for epinephrine added to a local anesthetic-opioid combination

The results suggest that adding epinephrine to a combination of standard intrathecal doses of bupivacaine and fentanyl in combined spinal-epidural analgesia for labor significantly prolongs spinal analgesia. Of the four epinephrine doses tested, the lowest one (12.5 μg) was optimal for this clinical setting.