Abstract: Objective To evaluate the analgesia effects of ultrasound-guided quadratus lumborum block in patients undergoing laparoscopic renal cyst unroofing.Methods Sixty ASA Ⅰ or Ⅱ patients，scheduled for elective laparoscopic unroofing of renal cyst，were randomly divided into two groups（n=30）：ultrasound-guided QLB combined with general anesthesia group（group QLB）and simple general anesthesia group（group C）.In group QLB，QLB was performed with 25ml of 0.4% ropivacaine injection in operation side after induction of general anesthesia ，while group C received simple general anesthesia.Intraoperative sufentanil dosage，visual analogue scores（VAS）at different postoperative time points，first compression time of postoperative analgesia pump，total postoperative sufentanil dosage，number of postoperative analgesia，incidence of nausea and vomiting，and patient satisfaction with analgesia were observed and recorded.Results The consumption of intraoperative and postoperative sufentanil in group QLB were （27.3±5.2）μg and （16.2±6.6）μg;the VAS of 2，4，6，8，12，24h of post-operation were 1.4±0.7，1.6±0.6，1.6±0.6，2.0±0.7，2.1±1.0，2.1±1.1，respectively;first compression time of analgesic pump was （684.3±162.7）min;the times of remedial analgesia and nausea or vomiting was 5 and 3;patient satisfaction with postoperative analgesia was 7.7±1.3.While in group C was（32.8±3.6）μg，（61.9±22.9）μg，2.1±0.9，2.8±0.9，3.6±0.8，3.0±1.2，3.0±1.5，2.9±1.2，（56.6±14.9）min，12 cases，10 cases，6.9±1.4，respectively.The difference between the two groups was statistically significant（P<0.05）.Conclusion Ultrasound-guided QLB with 0.4% ropivacaine can reduce the opioid consumption and enhance the efficacy of postoperative analgesia for patients under going laparoscopic renal cyst unroofing.It can improve the patient's comfort and satisfaction.

Key words: ultrasonography, quadratus lumborum block, renal cyst unroofing, analgesia