Abstract: Objective  To retrospectively analyze the effect of quadratus lumborum block on postoperative acute pain of patients undergwent laparoscopic hepatectomy.　Methods　Twenty-four patients who underwent selective laparoscopic hepatectomy under total intravenous general anesthesia in our hospital from January to August 2018 were selected. Patients who only accepted total intravenous general anesthesia were assigned to the control group. Patients who accepted total intravenous general anesthesia (TIVA) combined with quadratus lumborum block (QLB) were assigned to the QLB group. All patients accepted patient controlled intravenous analgesia (PCIA) for postoperative analgesia. Heart rate, blood pressure, and pulse oximetry were routinely monitored during anesthesia. The blocked area of patients was tested and recorded 15 min after quadratus lumborum block. VAS scores were obtained before surgery, and 2 h, 8 h, 12 h, 24 h, and 48 h after surgery. Opioids consumption during the operation and PCIA were also recorded. Additionally, postoperative complications such as nausea and vomiting, urinary retention, itching and respiratory depression during 48 h after surgery were also recorded.    Results    VAS scores in QLB group were significantly lower than those in the control group at 2, 8 and 12 h postoperatively. And the difference was statistically significant (P<0.05). The highest and the lowest block plane of the 12 patients in QLB group was T6 (T6~10) and L1 (T12~L1), respectively. Compared with the control group, the opioids consumption during the operation and PCIA of QLB group was significantly decreased and the difference was statistically significant (P<0.05).　Conclusions　Quadratus lumborum block can effectively relieve postoperative acute pain in patients undergoing laparoscopic hepatectomy and reduce the opioids consumption during perioperative period. 

Key words: Quadratus lumborum block, 　Hepatectomy, 　Pain, 　Retrospective study