Effects Of Individualized Intraoperative Blood Pressure Management On Neurocognitive Function In Elderly Patients Undergoing Surgery

Objective Perioperative neurocognitive disorders(PND)is a common neuropsychiatric complication in elderly patients after surgery,mainly including postoperative delirium(POD)and postoperative cognitive dysfunction(POCD).Intraoperative hypotension is a perioperative adverse event and one of the risk factors of PND,which seriously affects the patient’s intraoperative safety and postoperative recovery.Effective prevention and treatment of intraoperative hypotension may reduce the occurrence of PND,but there is currently no unified perioperative blood pressure management standard,and the impact of different blood pressure levels on PND is not clear.This article studies the effect of individualized intraoperative blood pressure management methods on the neurocognitive function of elderly patients undergoing abdominal surgery,in order to provide a reference for the formulation of the optimal level of blood pressure management in elderly surgical patients.Methods Ninety patients undergoing elective radical resection of gastric cancer or radical resection of colorectal cancer were included in this study,aged 65 years or older,70 males and 20 females,and American Society of Anesthesiology(ASA)anesthesia risk grade I ～Level III.They were divided into two groups using a random number table.Control group(group B): maintenance of SBP ≥90 mm Hg or SBP drop does not exceed 40% of the basic value.Individualized group(group A): intraoperative maintenance of SBP levels above 90% of the basic value,After induction of anesthesia,the patient underwent tracheal intubation and mechanical ventilation.Intraoperative anesthesia was maintained by intravenous anesthesia.Record operation time,intraoperative fluid infusion,use of vasoactive drugs,time to place drainage tube,first postoperative ventilation time,hospital stay,etc.Record the pre-induction(T0),start of surgery(T1),30 min(T2),60 min(T3),90 min(T4),120 min(T5),150 min(T6),and end of surgery(T7)after the start of surgery(T7)SBP,heart rate(HR)and bispectral index(BIS).One day before surgery,the Mini-Mental State Examination was used to assess the patient’s baseline cognitive function,The Confusion Assessment Method-Chinese Reversion and MMSE scale were used on the 1,3,and 7 days after surgery to evaluate short-term neurocognitive function after surgery.One month after the operation,the Telephone Interview for Cognitive Status was used to assess the patient’s cognitive function after discharge.And the patient’s hospital stay and severe complications such as lung infection,congestive heart failure,myocardial infarction,acute kidney injury,and stroke were recorded.Results1.Preoperative basic data of the two groups of patients: there was no statistically significant difference in baseline data such as gender,age,ASA classification,preoperative MMSE score,etc.between the two groups(P>0.05).2.Intraoperative and postoperative general conditions of the two groups of patients:There was no significant difference in the intraoperative anesthetic dosage and the use of ephedrine,esmolol,and nicardipine vasoactive drugs between the two groups.The number of norepinephrine users in the individualized group was significantly more than that of the control group(P<0.05),and the postoperative drainage tube placement time and hospital stay in the individualized group were shorter(P<0.05).There were no statistically significant differences in operation time,fluid input,blood loss,urine output,postoperative whereabouts,and first ventilation time between the two groups.3.Comparison of BP,HR and BIS values at different time points in the two groups of patients: Compared with T0,SBP,MAP and BIS in T1～T7 groups were significantly reduced(P<0.05),and DBP in T1～T3 and T5～T7 groups Significantly reduced(P<0.05).Compared with T0,HR in T1～T6 groups was significantly slower(P<0.05).The levels of SBP and MAP in the T1～T7 individualized group were significantly higher than those of the control group(P<0.05),and the DBP of the individualized group at T4 was significantly higher than the control group(P<0.05).4.Comparison of postoperative neurocognitive function and postoperative complications of the two groups of patients: Compared with the preoperative basic level,the MMSE scores of the two groups were significantly reduced on the 1st and3 rd day after the operation(P<0.05).The MMSE score was significantly reduced on day 7(P<0.05).Compared with the control group,the MMSE score of the individualized group was significantly increased on the 1st and 3rd day after surgery(P<0.05),the difference between the MMSE score and the preoperative MMSE score(?MMSE)was significantly reduced(P<0.05),CAM-CR score was significantly reduced(P<0.05).There was no significant difference in VAS scores between the two groups at 1 and 3 days after surgery(Table 5);there was no significant difference in TICS-m scores between the two groups at 30 days after surgery.There were 17 cases(37.8%)in the control group and 15 cases(33.3%)in the individualized group with cognitive impairment,and the difference was not statistically significant(P>0.05).There were 12 cases of severe complications in the two groups of patients within one month after surgery,including 7 cases(15.6%)in the control group and 5 cases(11.1%)in the individualized group.There was no statistically significant difference in the incidence of complications between the two groups(P >0.05).Conclusion During surgery in elderly patients,maintaining systolic blood pressure above 90% of the basic value can improve early postoperative neurocognitive function and shorten the length of hospitalization,but it has no significant effect on neurocognitive function one month after surgery.