Effect Of Controlled Hypotension Under Monitoring Of Cerebral Oxygen Saturation On Postoperative Delirium In Elderly Hypertensive Patients With Shoulder Arthroscopic Surgery In Beach Chair Position

Objective:To investigate the effect of controlled hypotension under monitoring of cerebral oxygen saturation on postoperative delirium in elderly hypertensive patients with shoulder arthroscopic surgery in beach chair position.Methods:Sixty elderly hypertensive patients in our hospital with shoulder arthroscopic surgery under general anesthesia in the beach chair position,aged 65-80 years,ASAⅡ～Ⅲ,hypertension grade 1～2,were selected and randomly divided into group R(rScO2 group)and group C(control group),30 patients in each group.Electronic micro-pumps were used to inject nitroglycerin for controlled hypotension in both groups to maintain MAP no less than 70% of the base value,and MAP no less than 70 mm Hg.When group R rScO2 less than 90% of the basic value or absolute value of rScO2 less than 60%,and the duration was more than 10 seconds,the blood pressure was improved by adjusting the infusion parameters until rScO2 no less than90% of the basic value or the absolute value of rScO2 no less than 60%.The rScO2 monitor in group C was covered.HR,MAP and rScO2 values were recorded at different time points: T0(5 minutes before anesthesia administration),T1(5 minutes after changing to beach chair position),T2(15 minutes after controlled hypotension),T3(30 minutes after controlled hypotension),T4(5 minutes after controlling blood pressure reduction and changing the supine position)and T5(10 minutes after extubation);the lowest value of rScO2 during the operation and the maximum percentage of the lowest value of rScO2 decreased from the baseline value were recorded.POD was assessed by CAM-CR in the first three days after operation.The total amount of intraoperative propofol,remifentanil and nitroglycerin were recorded.At the same time,PACU stay time,hospital days and the occurrence of major adverse events(such as myocardial infarction,stroke,acute kidney injury,etc.)within 7 days after operation were compared between the two groups.Results:1.There was no statistically significant difference between the two groups of patients in terms of general information,surgery-related indicators,total amount of propofol used,total amount of remifentanil used,and HR at each time point(P >0.05).2.The intraoperative nitroglycerin dosage of the two groups was compared,the difference was statistically significant(P < 0.05),and the nitroglycerin dosage in group C was significantly higher than that in group R.3.There was no statistically significant difference in MAP and rScO2 between the two groups at T0,T1,T4,and T5(P >0.05).The MAP in group R was significantly higher than that in group C at T2(P < 0.05);the difference of MAP between the two groups at T3 was not statistically significant(P > 0.05);and the rScO2 in group R was significantly higher than that in group C at T2,T3(P<0.05).4.The time trends of MAP and rScO2 were statistically significant(P<0.05),the overall trends of the two groups decreased significantly and then rose again,and basically recovered to the T0 level at T5.Compared the two groups at different time points,the MAP of the two groups was the lowest at T3,followed by T2,T1,T4,and the highest at T0,and T5 was slightly lower than T0.The rScO2 in group C was the lowest at T3,followed by T2,T1,T4,and T0 gradually increased,and T5 was slightly lower than T0;the rScO2 in group S was the lowest at T1,followed by T2 and T3,then T4 and T5,and T0 was the highest.5.The lowest value of rScO2 in group R during operation was significantly higher than group C(P<0.05);the maximum percentage of the lowest value of rScO2 decreased from the baseline value in group R was significantly lower than that in group C(P<0.05).6.The PACU stay time and hospital days in group C was significantly higher than that in group R(P<0.05).7.The incidence of POD at 1 day after operation in group R was significantly lower than that in group C(P<0.05);there was no significant difference in the incidence of POD between the two groups at 2 and 3 days after operation(P>0.05).There was no significant difference in the occurrence of major adverse events within7 days after operation between the two groups(P>0.05).Conclusion:Controlled hypotension with cerebral oxygen saturation monitoring can reduce the occurrence of postoperative delirium in elderly hypertensive patients with shoulder arthroscopic surgery in beach chair position,improve the perioperative safety,and facilitate the rapid recovery of patients.