Effectiveness of ropivacaine and fentanyl for postoperative epidural analgesia following thoracic surgery

Background: Epidural ropivacaine is now a common drug used for postoperative analgesia. However, little information is available concerning regression of sensory blockade and analgesia following prolonged epidural infusion of ropivacaine. We investigated the efficacy of ropivacaine and fentanyl for postoperative analgesia after thoracic surgery. Methods: Thirty patients undergoing thoracic surgery were enrolled. After surgery with general and thoracic epidural anesthesia, continuous epidural infusion of 0.2% ropivacaine+fentanyl (1.67 μg·ml^-1) was started at a rate of 6 ml · h^-1 for patients whose height was more than 155 cm and 4 ml·h^-1 for those below 155 cm with possibility of an additional bolus injection of 3 ml at least every 60 min. Results: An additional epidural injection of 3 ml produced a decrease in VAS without significant changes of vital signs. The greatest VAS was 10± 25 mm in the incision site and 36±38 mm in the ipsilateral shoulder. Sensory blockade was sustained until the morning after the day of surgery. Also blood pressure and heart rate were stable throughout the observation period. There were no adverse effects except for slight nausea in three patients. Conclusions: A bolus of 3 ml with continuous 4-6 ml·h^-1 epidural injection of ropivacaine plus a small dose of fentanyl would decrease postoperative pain with stable vital signs in patients after thoracic surgery.