Effects Of Different Dosages Of Lidocaine On Postoperative Delirium In Elderly Patients Undergoing Thoracoscopic Pneumonectomy

Objective:To observe the effect of different doses of lidocaine on the incidence of postoperative delirium,anesthesia recovery time,and postoperative pain in elderly patients undergoing thoracoscopic pneumothorax,and to investigate the effect of different doses of lidocaine on postoperative delirium impact and possible mechanisms.Methods:One hundred and twenty patients scheduled for thoracoscopic pneumonectomy（lobectomy,segmentectomy,wedge resection）in people’s hospital of deyang city from January 2017 to January 2018,with no gender,age≥60 years,ASA gradeⅡorⅢ.The present study is a randomized double-blinded trial,all patients were divided into 3 groups,normal saline group（C group）,lidocaine group A（group LA）and lidocaine group B（group LB）.group LA:patients received a dose of lidocaine（2%）via an intravenous bolus（1mg/kg）before induction followed by an infusion at a rate of 1 mg.kg^-1.h^-1 until the end of surgery.group LB:patients received a dose of lidocaine（2%）via an intravenous bolus（2mg/kg）before induction followed by an infusion at a rate of 2 mg.kg^-1.h^-1 until the end of surgery.C group:prior to induction of anesthesia,normal saline（0.9%NaCl）was continuously infused at a rate of 1ml.kg^-1.h^-1 for 15 minutes,followed by intravenous infusion at a rate of 0.25 ml.kg^-1.h^-1.All patients were induced and maintained with propofol,sufentanil,rocuronium.The depth of anesthesia was monitored using the bispectral index scale（BIS）which was maintained in the range of 40-60.Observed and recorded the patient’s hemodynamics during the operation;recorded the operation time,bleeding volume,infusion volume,urine output,anesthesia recovery time,anesthesia recovery room stay time,leavening operation room time.Visual analogue scale（VAS）score and analgesia pump press times were recorded at 1,2 and 3 days after operation.Peripheral venous blood was collected from the three groups before induction of anesthesia（T0）,12 hours（T1）,24 hours（T2）and 48hours（T3）postoperatively.Plasma S-100β,IL-1β,TNF-αand IL-6concentrations were assessed by enzyme linked immunosorbent assay（ELISA）.Delirium was diagnosed by DSM-5 criteria with the Confusion Assessment Method-Intensive Care Unit（CAM-ICU）on the first day,the second day and the third day after surgery.Result:1)There was no statistically significant difference between the groups in terms of demographic data.The numbers of lobectomy,segmentectomy and wedge resection surgeries were similar,surgery and anesthesia duration was comparable.2)Compared with group C,mean blood pressure and heart rate was significantly lower in group LA and group LB at the time of intubation and extubation（p<0.05）.3)Compared with group C,the anesthetic resuscitation time,the time of leaving the operating room were significantly shortened in the group LA and group LB（p<0.05）.The incidence of postoperative agitation was significantly decreased in the group LA and group LB（p<0.05）.4)On the 1st,2nd and 3rd days after operation,there was no statistical difference in the pain degree scores among the three groups（p>0.05）.Compared with group C,the number of PCA compressions on the first postoperative day was significantly reduced in the LA and LB groups,with a significant difference（p<0.05）.There was no significant difference in the anus ventilation time between the three groups（p>0.05）.5)Compared to T0,plasma S-100β,IL-1β,IL-6,and TNF-αconcentrations were significantly increased in three groups at T1 and T2,amd in group C at T3.Plasma S-100β,IL-1β,IL-6,and TNF-αconcentrations were significantly decreased in the group LA and group LB compared to the group C at all times.6)Within 3 days after surgery postoperative delirium occurred in 10 patients（29.4%.）in the C group,in 6 patients（18.8%.）in the group LA and in 6 patients（16.7%.）in the group LB.There was no statistical difference between the three groups（p<0.05）.Conclusion:1)Intraoperative continuous infusion of lidocaine can reduce serum concentrations of S-100β,IL-1β,IL-6,TNF-α,but can not reduce the incidence of postoperative delirium.2)Intraoperative continuous injection of lidocaine can shorten the anesthesia recovery time,reduce the incidence of agitation in the recovery room,and shorten the recovery room residence time.3)Intraoperative continuous injection of lidocaine can reduce the amount of opioids used on the first postoperative day,but it does not reduce the recovery time of gastrointestinal function.