Clinical benefits of preemptive thoracic epidural analgesia with hydromorphone and bupivacaine in open thoracotomy lung surgery

Abstract

Background: Preemptive analgesia is known to decrease the sensitization of the central nervous system and reduce subsequent amplification of nociceptive stimuli. We investigated whether preemptive thoracic epidural analgesia (TEA) demonstrated intraoperative and postoperative short and long term clinical advantages. Methods: Thirty patients scheduled for open thoracotomy were randomly allocated to one of two groups to receive continuous TEA (0.15% bupivacaine and 8 μg/ml hydromorphone) either before surgical incision (preemptive group) or at the end of the operation (nonpreemptive group). Incidence of hypotension during surgery was recorded. Numerical rating scales (NRS) and the incidence of side effects such as nausea, pruritus, sedation, hypotension, and respiratory depression were recorded at 2, 6, 24, and 48 hours postoperatively. Pulmonary function test (PFT) was performed before, 24 and 48 hours after the operation. Persistence of pain control was investigated at 6 months postoperatively. Results: The NRS score, side effects, and PFT changes were comparable between the two groups. TEA and intravenous rescue morphine consumed at 2, 6, 24, and 48 hours postoperatively were not different between the two groups. During surgery, the incidence of hypotension was significantly higher in the preemptive group (P = 0.027). At 6-month follow up, two patients in the nonpreemptive group complained of persistent pain at wound and none in the preemptive group. Conclusions: Preemptive TEA with hydromorphone and bupivacaine during surgery may cause unnecessary intraoperative hypotension without a prominent advantage in reducing acute or chronic pain or enhancing pulmonary function after thoracotomy. The advantageous concept of preemptive TEA may be dubious and may not provide perioperative clinical benefits.