Effect Of Serratus Plane Block On Remifentanil Consumption And Postoperative Analgesia In Modified Radical Mastectomy

Objective Serratus plane block(SPB)is a new type of ultrasound-guided nerve block that has been used in the treatment of persistent pain after breast cancer surgery,analgesia after thoracotomy,rib fracture pain treatment and shoulder surgical treatment.Many studies have confirmed that SPB can reduce postoperative pain in breast cancer and reduce adverse reactions such as postoperative nausea and vomiting.However,the intraoperative role of SPB has been ignored.We used a closed-loop target controlled infusion(CLTCI)device guided by a bispectral index(BIS)to monitor SPB to reduce intraoperative propofol and remifentanil consumption.Second,we observed the effect of SPB on postoperative analgesia in breast cancer patients.Methods The present study was approved by the Ethics Committee of Yantai Yuhuangding Hospital of Qingdao University(Yantai,China).Written informed consent was obtained from all participants prior to randomization.Fifty-two patients undergoing unilateral modified radical mastectomy and axillary dissection were randomized into two groups: general anesthesia(Group G,n=26),general anesthesia combined with serratus plane block(Group SPB,n=26).General anesthesia was induced and maintained with same regime for both groups.The patients in group SPB were given the general anesthesia combined with ultrasound-guided serratus plane block with 20 ml of 0.375% ropivacaine,and the patients in group G were given the general anesthesia.General anesthesia was maintained with the same closed-loop titration guided by the BIS to 45-55.Mechanical ventilation was maintained by laryngeal mask airways in two groups.The first outcome variable was perioperative propofol and remifentanil consumption.The other outcomes variable were postoperative pain intensity at rest and arm movement,which was assessed at 2,4,8,16 and 24 h after surgery using the visual analogue scale(VAS).The consumption of sufentanil after surgery and any adverse effects were recorded.SPSS23.0 software was used for statistical standard deviation,t test,chi square test and analysis,provisions of P<0.05 had statistical significance.Results There was no significant difference in demographic data between the two groups.Patients with serratus plane block required less remifentanil [(292.12 ± 20.84)?g vs.(375.00±34.12)?g]than the group G(P<0.05).The consumption of propofol was similar in both groups [(640.38±19.23)mg vs.(645.77±26.48)mg,P=0.406].During the first 24 hours,patients in Group SPB had a lower VAS both at resting(at time point of 2,4 and 8 h after surgery)and arm movement states(at time point of 2 and 4 h after surgery)(P<0.05).The postoperative dose of sufentanil [(55.02±5.54)?g vs.(68.75±6.85)?g ] and the incidence of postoperative nausea and vomiting was significantly lower than that of group G(P<0.05).There were no adverse reactions in both groups.Conclusion The ultrasound-guided serratus plane block significantly reduced the requirement remifentanil use during maintenance of anesthesia,had an effective postoperative analgesia after radical mastectomy,and reduced the adverse reactions of opioid analgesics.Secondly,the serratus plane block has simple operation and less complications,and has broad application prospects in clinical practice.