Analysis Of Anesthesia Effect Of Closed Loop And Open Loop Target Controlled Infusion Of Propofol In Obese Patients Under The Guidance Of Bis

OBJECTIVE:To study the anesthetic effect of closed loop and open loop target controlled infusion of propofol under the guidance of BIS in the operation of obese patients,and to further explore the advantages of closed loop target controlled infusion system of propofol,as well as the safety and feasibility of its application in this kind of special patients,so as to provide clinical reference.METHODS:A total of 60 obese patients,aged 18-60 years old,with BMI28～40 kg/m~2,ASA I/Ⅱ,were selected for surgical treatment under general anesthesia during May 2020 to January 2021.According to the random number table method,the patients were divided into closed loop group(group C)and open loop group(group O),with 30 cases in each group.After anesthesia induction endotracheal intubation,during the maintenance of anesthesia,BIS values were used as the feedback variable,closed loop target controlled infusion and open loop target controlled infusion of propofol were used in the two groups,respectively.The target plasma concentration of remifentanil was manually adjusted,and the target concentration of remifentanil was adjusted according to the degree of intraoperative stimulation combined with the patient’s heart rate and blood pressure.The patients’gender,age,height,weight,BMI values,ASA grade,types of surgery,length of surgery,length of anesthesia,intraoperative infusion volume,operation bleeding volume,total overall narcotic usage,and artificial adjustment times of propofol and remifentanil during anesthesia were recorded.HR,MAP and BIS were recorded before anesthesia induction(T0),immediately after tracheal intubation(T1),skin incision(T2),30min at the beginning of surgery(T3)and at the end of surgery(T4).The incidence of cardiovascular adverse effects and the use of vasoactive drugs during perioperative period were recorded.Postoperative extubation time and stay time in PACU were recorded.RESULTS:There were no significant differences in gender,age,height,weight,BMI,ASA grade and types of surgery between 2 groups(P>0.05).There were no significant differences in length of surgery,length of anesthesia,intraoperative infusion volume and operation bleeding volume between 2 groups(P>0.05).Compared with the O group,the total amount of propofol,the used dose and the times of artificial adjustment in the C group were significantly decreased(P<0.05),while the total consumption of remifentanil,the used dose and the times of artificial adjustment in the two groups had no statistical significance(P>0.05).There was no significant difference in the amount of fentanyl,cisatracurium and tolisetron during the operation(P>0.05).There were no significant differences in MAP,HR and BIS values between 2 groups at each time point(P>0.05).There was no statistical significance in the incidence of bradycardia,tachycardia,hypotension and hypertension between 2 groups(P>0.05).There was no statistical significance in the utilization rates of atropine,esmolol,ephedrine and urapidil between 2 groups(P>0.05).There was no significant difference in postoperative extubation time and PACU residence time between 2 groups(P>0.05).CONCLUSIONS:Compared with open loop target controlled infusion,closed loop target controlled infusion under the guidance of BIS can reduce the total propofol dose and the times of manual intervention,reduce the workload of anesthesiologists to a certain extent,improve the quality and safety of anesthesia.