Background: Postoperative pain after radical retropubic prostatectomy is moderate to severe. The primary aim of this study was to assess whether intra-abdominal local anaesthetics provide similar analgesia compared with thoracic epidural analgesia (TEA).
Methods: Fifty patients, ASA I-II, participated in this prospective, double-blinded study. All patients had TEA. After operation, they were randomized into two groups of 25 patients: Group PCLA (patient-controlled local analgesia): self-administration of 10 ml of ropivacaine 2 mg ml⁻¹ via the intra-abdominal catheter for 48 h. Group TEA: infusion of 10 ml h⁻¹ of ropivacaine 1 mg ml⁻¹, fentanyl 2 μg ml⁻¹, and epinephrine 2 μg ml⁻¹ epidurally for 48 h. The primary endpoint was pain on coughing at 4 h after operation. Rescue medication was morphine i.v. as required.
Results: Pain on coughing at 4, 24, and 48 h was significantly lower in Group TEA [0 (0-10)] compared with Group PCLA [4 (0-10)] (P<0.05). Significantly lower pain intensity was also found in Group TEA compared with Group PCLA at the incision site, deep pain, and pain on coughing at 4 and 24 h (P<0.05). Morphine consumption was significantly greater in Group PCLA [12 (0-46)] compared with Group TEA [0 (0-20)] at 0-48 h after operation [median (range)] (P=0.015). Maximum expiratory pressure was higher in Group TEA compared with Group PCLA at 24 h (P<0.01).
Conclusions: TEA provides superior postoperative pain relief with better preservation of expiratory muscle strength compared with PCLA.