Quantitative Monitoring Of Brain Function Status Guided The Clinical Study Of Propofol And Remifentanil In Laparoscopic Subtotal Gastrectomy

1.To evaluate the distribution of the brain function status index of gastric cancer patients before surgery and its possible influence on the amount of propofol during surgery,so as to determine the proper dose of propofol during gastric cancer surgery.2.To evaluate the clinical effect of target-controlled infusion of remifentanil in laparoscopic major gastrectomy under the monitoring of Pain Threshold index（PTi）,and to prove its superiority in maintaining the analgesic depth of the body for clinical guidance.Methods:1.Features of brain function status index monitoring in patients with gastric cancer and its effect on propofol dosage during perioperative period.Thirty-five patients with gastric cancer（test group）and the same numble of non-tumor patients（Control group）were scheduled for elective surgery under intravenous anesthesia.All patients underwent open-loop target-controlled infusion of propofol and remifentanil with wavelet index（WLi）and Pain Threshold index（PTi）as feedback indicators,and their indices were maintained at 45-55.EEG monitoring was performed using the HXD-I Multi-Function Combination Monitor.In this study,the pulse pressure variation rate（PPV）was used to guide intraoperative fluid therapy and the application of vasoactive drugs.All patients underwent open-loop target-controlled infusion of propofol and remifentanil with wavelet index（WLi）and Pain Threshold index（PTi）as feedback indicators,and their indices were maintained at 45-55.and the muscle relaxation monitoring feedback instrument for the closed-loop infusion of rocuronium bromide.The trends of intraoperative WLi PTi and PPV in the two groups were compared。The preoperative brain function status index of the two groups was recorded,including cognitive index,Delirium index,Introspective Intensity,Working Memory Function index,Cognitive Efficiency,Selective Attention,and Left/Right Brain Utilization.etc.During anesthesia induction,the propofol requirement and the instant plasma concentration of propofol when the eyelash reflex disappeared were recorded.The minutes of propofol required during the anesthesia,the total amount of infusion during the operation,and the use of vasoactive drugs were recorded.The postoperative awake time,extubation time,directional force recovery time and PACU stay time were recorded.Pearson correlation was used to analyze the correlation between the propofol requirement when the eyelash reflex disappeared and the cognitive index of brain function status.2.Pain Threshold index（PTi）guides the application of remifentanil target-controlled infusion in laparoscopic gastrectomy.Fifty patients with gastric cancer who underwent elective gastric resection were randomly divided into two groups,25 in each group.The observation group used the HXD-I multi-function combination monitor for EEG monitoring.The plasma concentration of remifentanil was adjusted according to the Pain Threshold index（PTi）.The amplitude of each adjustment was 0.5 ng/ml,and the Pain Threshold index was maintained at 40⁶0.In the control group,the patient TCI infused 3-5ng/ml remifentanil for anesthesia maintenance,and the dose was appropriately adjusted according to the surgical stimulation.The anesthesia time,recovery time and extubation time,and the doses of remifentanil and propofol were recorded.VAS scores immediately after awakening and at 15 and 30 minutes after awakening were compared between the two groups.The differences in serum stress hormone ACTH,AngII,β-endorphin and blood glucose levels between the two groups before anesthesia induction,1 h and 2 h after skin incision,immediately after waking were compared.Heart rate（HR）and mean arterial pressure（MAP）were Recorded at the following time point:before anesthesia induction（T₀）,endotracheal intubation（T₁）,skin incision（T₂）,exploration（T₃）,at the end of the operation（T₄）and extubation（T₅）。Result:1.There were no significant differences in age,sex composition,years of education,and the body mass index between groups（P>0.05）.The WLi and PTi values of the two groups of patients before the induction of anesthesia were in the range of 90-100,and the difference was not statistically significant（P>0.05）.During the maintenance of anesthesia,the WLi and PTi values of the two groups of patients were maintained in the range of 45-55.There was no significant difference in WLi and PTi values between the two groups of patients over time from before induction to wake-up（P>0.05）.The intraoperative PPV of the two groups of patients was maintained between 5-13%,and there was no significant difference in their trends（P>0.05）.Compared with the control group,patients with gastric cancer had significantly lower cognitive index and the Left/Right Brain Utilization index,while Cognitive Efficiency and the Introspective Intensity index were higher（P<0.05）.There was no significant difference in the Delirium index,Amnesia index,Working Memory Function index and Brain Metabolism Rate between the two groups（P>0.05）.In addition,Left/Right Brain Utilization,Cognitive Efficiency and the Introspective Intensity index of gastric cancer patients were outside the reference range,and the control group was basically normal.Compared with the control group,when the eyelash reflex disappeared in the observation group,the propofol requirement,the immediate plasma concentration of propofol,and the per minute requirement of propofol during the operation were significantly reduced（P<0.05）.There was no significant difference in the use of remifentanil and rocuronium between the two groups.（P>0.05）.Compared with the control group,the total infusion volume,atropine,and ephedrine use in the observation group were significantly increased（P<0.05）,and the postoperative wake-up time,extubation time,directional force recovery time,and PACU retention time were significantly longer（P<0.05）.0.05).Pearson correlation analysis shows that there is a clear correlation between propofol requirement and cognitive index（R₂=0.654 P<0.001）and the Introspective Intensity index（R₂=0.554 P<0.001）,but there was no obvious correlation with Cognitive Efficiency and the Left/Right Brain Utilization index（P>0.05）.2.In the case of target-controlled infusion of remifentanil,compared with the control group,the wake-up time and extubation time were significantly shorter（P<0.05）,and the dose of remifentanil was also significantly reduced（P<0.05）,the number of ephedrine and atropine use cases increased significantly（P<0.05）.Immediately after awakening and at 15 and 30 minutes after awakening,the VAS scores of patients in the observation group were significantly lower than those in the control group（P<0.05）.Compared with A₀,the levels of ACTH,AngII,andβ-EP in the serum of the two groups were significantly increased at A₁,A₂,and A₃（P<0.05）;There was no significant difference in serum ACTH,AngII,β-EP and blood glucose levels between the two groups at A₀;the contents of ACTH,AngII,β-EP,and blood glucose in the observation group at A₁,A₂,and A₃ were significantly lower than the corresponding time points in the control group（P<0.05）.The HR and MAP of the observation group are more stable than those of the control group.The HR of the observation group is significantly slower than that of the control group at T₂,T₃,T₅（P<0.05）,and the HR of the observation group is significantly faster than that of the control group In the control group（P<0.05）,there was no statistically significant difference in HR between T₀ and T₁.The MAP of the observation group was significantly lower than that of the control group at T₃ and T₅（P<0.05）,and the MAP of the observation group was significantly higher than the control group at T₄（P<0.05）.significance.Conclusion:1.The brain function status index of gastric cancer patients showed specific changes,suggesting that cancer may cause cognitive impairment and emotional changes in gastric cancer patients,and there is a certain correlation between the propofol requirement of patients and cognitive index and the Introspective Intensity index when underwent laparoscopic gastrectomy.2.Patients undergoing laparoscopic subtotal gastrectomy receive target-controlled infusion of remifentanil under PTi monitoring,which is closer to or consistent with the guidance of precise anesthesia and the safe and rational application of analgesics in general anesthesia.