In a previous report, epinephrine was found to markedly improve the analgesic effect of a thoracic epidural infusion of bupivacaine and fentanyl. In this study we evaluated the effects of adding epinephrine to patient-controlled epidural analgesia (PCEA) based on a bupivacaine and fentanyl mixture after gynecological surgery.

Forty women undergoing lower abdominal gynecologic surgery under general anesthesia were randomized in a double-blind fashion to receive one of two regimens of; PCEA; 0.0625% bupivacaine with 2 microgram/ml fentanyl and 2 microgram/ml epinephrine for the Epinephrine group, or 0.0625% bupivacaine with 2 microgram/ml fentanyl for the No-epinephrine group after standardized combined epidural and general anesthesia. PCEA settings for the two groups were identical (4 ml/hr continuous background infusion, 2 ml bolus dose, 20 min lock-out period). Visual analogue scale (VAS) for pain at rest and on coughing, total volume infused, number of bolus infusions, and side effects such as nausea, vomiting, sedation, pruritus and motor block were recorded 2, 6, 12, 24, 36 and 48 hr postoperatively. Data are means ± SD.

No differences in VAS scores at rest and on coughing were observed between the groups. Incidences of hypotension and other side effects did not differ between the groups. Total volume infused was lower in the epinephrine group than in the control group at 24 hr (111±21 ml vs. 134±27 ml, P < 0.05) and at 48 hr (119±46 ml vs. 233±26 ml, P < 0.05). Similarly, the number of bolus infusions was lower in the epinephrine group than in the control group at 24 hr (8±6 vs 13±6, P < 0.05) and at 48 hr (12±8 vs 20±13, P < 0.05).

Epinephrine lowers the dose of bupivacaine and fentanyl needed for PCEA after lower abdominal surgery without reducing the occurrence of side effects.