 METHODS: 29 patients were divided into two groups. During the postoperative period, in the presence of pain, group 1 n 14 patients received 5 mL of a 100 mcg Fentanyl solution in saline without preservative by the epidural route and 2 mL saline intravenously. Group 2 n 15 patients received 5 mL saline by the epidural route and 2 mL 100 mcg Fentanyl intravenously. Analgesic supplementation consisted of 40 mg intravenous Tenoxicam and 5 mL epidural 0.25 bupivacaine if pain relief was not achieved with Tenoxicam. Pain intensity was evaluated by numerical scale and plasma concentrations of Fentanyl were measured simultaneously. 