Application Of Intravenous Infusion Of Lidocaine In Hysteroscopic Surgery Under Total Intravenous Anesthesia

Background:Studies have shown that intravenous infusion of lidocaine can reduce the requirements of propofol during colonoscopy,reduce postoperative pain and fatigue,and improve the quality of postoperative recovery.Hysteroscopy is an important method for the diagnosis and treatment of intrauterine lesions in modern gynecology.Although it is a minimally invasive surgery,many patients can still have moderate to severe pain or discomfort during hysteroscopy or hysteroscopic surgery.Hysteroscopic surgery is currently mostly performed under general anesthesia with propofol and opioid analgesics.The purpose of this study is to evaluate whether intravenous infusion of lidocaine can reduce propofol requirements in patients undergoing hysteroscopic surgery under total intravenous anesthesia,relieve postoperative pain,reduce the amount of opioid analgesics,and improve the quality of postoperative recovery.Methods:This study is a single-center,randomized,double-blind,placebo-controlled prospective clinical trial.Fifty-four patients,aged 18 to 65 years,ASA Ⅰ-Ⅱ,who underwent elective hysteroscopic surgery under propofol combined with fentanyl total intravenous anesthesia with laryngeal mask airway were included and randomly allocated into the lidocaine group(L)and the saline group(S).During the induction of anesthesia,fentanyl was administered ahead.After the subjects’ consciousness was blurred,patients in the lidocaine group received lidocaine with a 1.5 mg/kg intravenous bolus slowly,and followed by 3 mg/kg/h until the end of the operation,while patients in the saline group received the same amount of normal saline.Propofol was administered using target-controlled infusion under a Bispectral Index(BIS)-guided closed-loop anesthesia delivery system(CLADS)to maintain the bispectral index values at 50±5.The primary outcome measure was total propofol consumption;the secondary outcome measure was the patients’ pain score and use of analgesics during PACU.At the same time,the hemodynamic indexes during the operation and some adverse reactions related to lidocaine are also observed,including drowsiness,dizziness,visual impairment,seizures,numbness around the mouth,metallic taste,and arrhythmia.Results:A total of 54 patients were included in this study and randomized.One of the patients in the saline group was eliminated due to lack of propofol data during the operation,and a total of 27 patients in the lidocaine group and 26 in the saline group were finally included in the statistical analysis.Baseline data and surgical data were similar between the two groups.There was no significant difference regarding the total requirements of propofol(lidocaine group:saline group=293±133 mg:310±96 mg,P=0.233),pain score at 0(P=0.860)and 30 minutes(P=0.126)after entering PACU and intraoperatively fentanyl requirements(P=0.816),PACU fentanyl dosage(P=0.954)and total fentanyl consumption(P=0.830)between the two groups.No arrhythmia occurred during and after surgery in the two groups,and the incidence of adverse outcomes such as dizziness and drowsiness was not statistically different between the two groups.The amount of lidocaine in the lidocaine group was 136±43 mg.Conclusions:Intravenous infusion of lidocaine adjunct to total intravenous anesthesia during hysteroscopic surgery(i.v.bolus of lidocaine 1.5 mg/kg followed by a continuous infusion of 3 mg/kg/h until the end of surgery)could not significantly reduce the total requirements of propofol in BIS-guided closed-loop anesthesia delivery system,and had no significant benefit effect on the pain score and the total consumption of opioid for half an hour after surgery.No adverse results related to lidocaine exposure were reported.