Postoperative Pain After Total Laparoscopic Hysterectomy: a Comparison of Transumbilical Single-port Access and Conventional Three-port Laparoscopic Surgery

The randomization code was inserted into numbered and sealed envelopes. A single envelope was opened when the patient was arrived in operating room. All patients gave their informed consent for the study and underwent hysterectomy for benign diseases. After surgery, in all patients, three sticking plasters were applied by the same manner with three port surgery group therefore not only patients but also anesthesiology staff who measure the pain score could not know the type of surgery until data collection was finished. Pain was assessed according to the visual analog scale (VAS) (0 = no pain; 10 = worst pain imaginable). Patients were asked to evaluate the maximal degree of pain. Pain scores were recorded at least at 30 minutes, 1, 12, 24 and 48 hours after surgery. Postoperative pain was measured by two independent anesthesiology staff members for cross-checking. In order to compare the intensity of postoperative pain accurately, all the participants had anesthesia in the same way and postoperative pain was managed by fentanyl-based intravenous patient-controlled analgesia pump (IV-PCA, Baxter healthcare Corporation, U.S.A: bolus dose 0.12mg/kg of fentanyl, lockout interval of 5 min, basal infusion 0.02ml/kg) with the same regimen on both groups. A patient was instructed to press the IV-PCA bolus button when the VAS was 3 or higher. A patient under IV-PCA whose VAS was over 5 received 50mg of Tridol injection intravenously. IV-PCA was removed 48 hours after surgery unless a patient specially asked it. Then, using log data downloaded by a program, we analyzed the number of IV-PCA bolus requests by time interval, total amount of fentanyl consumption, and the number of additional Tridol administration and injection time.