Analgesia and pulmonary function after lung surgery: is a single intercostal nerve block plus patient-controlled intravenous morphine as effective as patient-controlled epidural anaesthesia? A randomized non-inferiority clinical trial

Abstract

Thoracic epidural anaesthesia (EDA) is regarded as the 'gold standard' for postoperative pain control and restoration of pulmonary function after lung surgery. Easier, less time-consuming, and, perhaps, safer is intercostal nerve block performed under direct vision by the surgeon before closure of the thoracotomy combined with postoperative i.v. patient-controlled analgesia with morphine. We hypothesized that this technique is as effective as thoracic EDA. The study was designed as a single-centre, open labelled, randomized non-inferiority trial. A total of 92 patients undergoing elective lung surgery were randomly assigned to the epidural (n=47) or intercostal group (n=45), and 83 patients completed the study. Pain scores, inspiratory vital capacity, forced vital capacity (FVC), forced expiratory volume in the first second (FEV1), and peak expiratory flow rate (PEFR) were assessed during the first four postoperative days. Median treatment differences regarding pain scores at rest failed to demonstrate non-inferiority of the intercostal nerve block at the first postoperative day. Patients of the intercostal group reported significantly higher pain scores on coughing during the first and second postoperative days. The epidural group had a significantly higher median FVC, FEV1, and PEFR values on the second postoperative day. No difference was found in pulmonary complications, length of hospital stay, or in-hospital deaths. In patients undergoing lung surgery, single intercostal nerve block plus i.v. patient-controlled analgesia with morphine is not as effective as patient-controlled EDA with respect to pain control and restoration of pulmonary function.