Anesthesia technique
NRS, ESPB, pain
The patients and their family members were informed of the anaesthesia related issues and the relevant information of the trial, and signed the informed consent. The patients were trained to use the numerical rating scale (NRS) method to assess pain (0–10 points, 0 is painless, 10 for maximum pain) and postoperative analgesia using a patient-controlled intravenous analgesia pump. Before induction of anesthesia, patients in group B were injected with 0.375% ropivacaine 30 mL on the operation side of T5 by the same experienced anesthesiologist for ultrasond-guided ESPB [All operations were performed by the same thoracic surgeon.The surgical incision was three-holes, with the main operating hole in the anterior axillary line between the 4th and 5th ribs, the thoracoscopic hole in the mid-axillary line between the 6th and 7th ribs, and the auxiliary operating hole in the posterior axillary line between the 8th and 9th ribs. The number of thoracic drainage tubes was one and the location was between the 6th and 7th ribs in the midaxillary line.PCIA pump was used in both groups after operation, and the drug formulation was: 2 µg/kg sufentanil, 10 mg tropisetron, and normal saline diluted to 150mL. The first dose was 2mL, the background dose was 2mL/h, the PCIA dose was 2mL, the locking time was 10 min, and the maximum dose was 10mL per hour. All patients were connected and started the patient-controlled intravenous analgesia pump 30 min before the end of the operation. In PACU or ward, when patients voluntarily requested analgesia or NRS score ≥ 4, the analgesic pump PCIA was pressed once, and the pain of patients was assessed again 15 min later. If the NRS score ≥ 4, intravenous dezocine 5 mg was given for relief analgesia, and the time of relief analgesia was recorded.