Postoperative analgesia in patients undergoing robot-assisted thoracic surgery: A comparison between thoracic epidural analgesia and intercostal nerve block combined with intravenous patient-controlled analgesia

Abstract

Background: Recently, robot-assisted thoracic surgery (RATS) is increasingly applied to lung or mediastinal tumor surgery. However, appropriate methods of postoperative analgesia for RATS have not been studied. Methods: Patients who underwent RATS at a single university hospital between January, 2017 and March, 2018 were studied retrospectively. Patients were anesthetized with either general anesthesia alone or combined general and thoracic epidural anesthesia. Accordingly, postoperative analgesia was managed with either intravenous patient-controlled analgesia (PCA) with fentanyl or thoracic epidural analgesia (TEA) with morphine and levobupivacaine. Patients were thus divided into 2 groups (PCA and TEA) according to methods of postoperative analgesia, and analgesic efficacies were compared between the groups with regard to pain scores evaluated on a 11-point numerical rating scale (NRS) at 0, 3, 6, 12, 18, 24, and 48 h postoperatively, rescue analgesic requirements within 24 h, side effects of anesthesia and analgesia, including respiratory depression, hypotension, nausea, pruritus, and urinary retention, time to ambulation after surgery, and hospital stay after surgery. Results: Data from 107 patients (76 in Group PCA and 31 in Group TEA) were analyzed. NRS pain scores at 6, 18, and 48 h were significantly less or tended to be less in Group TEA than in Group PCA (1.8±2.0 vs. 2.6±1.8, P=0.045; 1.7±1.5 vs. 2.4±1.8, P=0.047; and 1.9±1.4 vs. 2.5±1.6, P=0.063, respectively). The number of patients who required rescue analgesics within 24 h was significantly less in Group TEA than in Group PCA [4/31 (12%) vs. 32/76 (42%), P=0.004]. The other parameters were not significantly different between the groups. Conclusions: Compared with PCA, TEA provided better analgesia after RATS in terms of less pain scores, less rescue analgesic requirements, and similar side effect profiles. TEA with a hydrophilic opioid and local anesthetic seemed an appropriate method of postoperative analgesia in patients undergoing RATS.