| [Objective]To evaluate the effect of remote ischemic preconditioning(RIPC)on cerebral oxygen metabolism and postoperative cognitive function in elderly patients with single-lung ventilation lobectomy.[Methods]The study was approved by the Ethical Committee of the Third Clinical College of Kunming Medical University.Each patient signed an informed consent form.Selected 76 patients with non-small cell lung cancer(Ⅰ-Ⅱ)diagnosed by radiology and fiberoptic bronchoscopy between September 2017 and January 2018 and scheduled to undergo lobectomy under thoracotomy or thoracoscopic surgery,aged 60-75 years Body weight index(BMI)is between 18.5 and 23.9 kg/m2,with a body weight of 45 to 75 kg,and an ASA rating of<Ⅲ.New York Heart Association NYHA class I;no severe respiratory dysfunction(PaO2>60 mmHg or 1 second forced expiratory volume>50%of predicted value),normal coagulation function;no preoperative hypertension,diabetes,cerebrovascular,and peripheral Vascular disease;No history of chemotherapy,radiotherapy,immunotherapy;No corticosteroids used within 3 months;No central nervous system degenerative diseases(Alzheimer’s disease,Parkinson’s disease,etc.);All patients have received junior high school degrees Above education,there is no serious audio-visual impairment and normal communication with doctors.In accordance with the principle of randomized double-blind control,76 patients were divided into a control group(C group)and an experimental group(R group)by an anesthesia nurse.All patients did not use preoperative medication.Routine examinations of heart rate,blood pressure,pulse-oxygen saturation,and other vital signs were performed after admission.In the local anesthesia,the right subclavian vein was punctured,the right internal jugular vein was retrogradely placed,and the right radial artery was punctured.Tube.Slow intravenous injection of midazolam 0.05 to 0.1 mg/kg,sufentanil 0.6 μg/kg,etomidate 0.2 mg/kg,and vecuronium injection 0.1 mg/kg for anesthesia induction,all All patients were inserted into the left bronchial double-lumen tube.Fiberoptic bronchoscopy confirmed the catheter’s correct position and ensured an intraoperative SpO2≥95%.Before the start of the surgery,the anesthesia nurse bundled a pressurized tourniquet in the right lower limb of the two groups of patients.The pressure in the group C was maintained during the entire study.The pressure of the tourniquet was maintained at zero,and the R group was treated with remote ischemic preconditioning.Patients in the group were sent to follow-up studies by anesthesiologists who did not know the group.In the absence of distal pretreatment:5 min after issuance of ischemia by pressurizing the inflation pressure of the tourniquet to 200 mmHg,releasing the tourniquet pressure to produce reperfusion for 5 min,and thus repeating 3 cycles for 30 min.Intravenous pumping of propofol 4-8 mg kg-1·h-1 and remifentanil 0.1-0.2 μg·kg-1·h-1,inhalation of 1.5-2.0%sevoflurane with intermittent micro pump Intravenous injection of 2 to 4 mg vecuronium bromide maintains anesthesia.Adjust the dose of anesthetic to maintain the intraoperative BIS value of 40 to 60,adjust the respiratory parameters to maintain PaCO2 35～45 mmHg(1mmHg= 0.133 kPa).Use the same standardized fluid therapy to control the amount of fluid that is delivered when one lung is ventilated.Mean arterial pressure(MAP)≥ 65 mmHg and heart rate(HR)>50 beats/min were maintained during the operation.All patients received arterial blood before and after induction of anesthesia(T1),OLV 30min(T2).recovery of double-lung ventilation(TLV)15min(T3),recovery of TLV 60min(T4),60min(T5)after removal of double-lumen tubes,and Cerebral venous blood for blood gas analysis,calculation of oxygenation index(PaO2/FiO2),determination and calculation of cerebral oxygen metabolism related indicators(Da-jvO2,CjvO2,CaO2,CERO2);extraction of subclavian venous blood flow at the above time points Cytokines were used to measure cytokines(IL-6,TNF-α,IL-10)in inflammatory response;jugular veins were extracted before induction of anesthesia(T1),after 60 minutes(T5)after extraction of double lumens,and 24 hours(T6)after surgery.The blood of the bulb measures S-100β protein.The cognitive function of the patients was evaluated using the Mini-mental State Examination(MMSE)on the day before surgery(T0),24 hours(T6),and 7 days after the operation(T7).[Results]Seventy-six patients entered the final study and statistical analysis.The age,sex ratio,education composition ratio(university/high school/junior high school),BMI,ASA grade ratio,blood loss,fluid volume,and surgical method were used in the two groups.There were no significant differences in thoracotomy/thoracoscope,OLV time,and operative time.MAP and HR were not statistically significant at the corresponding time points in the two groups.Although there was no significant difference in SaO2 between the two groups at each time point,PaO2 and PaO2/FiO2 in group R increased significantly at each time point(P<0.05).PaO2/FiO2 in group R was 60 min after extubation(T5).It was 314.68±69.37mmHg,which had been restored to the level before the induction of anesthesia(T1).Compared with T1,both groups of PjvO2 and SjvO2 were significantly increased at T2,T3,T4,and T5(P<0.05),but PjvO2 in group R SjvO2 increased significantly at each corresponding time point compared with C group(P<0.05).Compared with Ti,both Da-jvO2 and CERO2 decreased significantly at T2,T3,T4,and T5(P<0.05).In group R,the corresponding time points decreased significantly more than in group C(P<0.05);compared with T1,IL-6 and TNF-a in both groups increased significantly at T2,T3,T4,and T5(P<0.05).However,there was no significant difference between the two groups at T2(P>0.05);at the T3,T4,and T5,the levels of IL-6 in the C group were 40.78±9.13,43.6±5.49,and 51.21 ±7.4 pg/ml,respectively,in the R group.The differences between the two groups were 35.52±8.74,40.17±7.11.and 43.73±4.89 pg/ml(P<0.05).The levels of IL-6 and TNF-α in the R group were lower than those in the C group..Compared with T1,the two groups of IL-10 were significantly higher at T2,T3,T4,and T5(P<0.05),but there was no significant difference between T2 and T2(P>0.05);T3,T4,At T5,the IL-10 levels in the C group were 39.42±4.16,42.11±4.41,and 43.97±4.21 pg/ml,respectively,and in the R group were 40.96±4.28,45.23±6.15,and 45.41±5.23 pg/ml,respectively.There was a statistical difference(P<0.05).The increase of IL-10 in group R was significantly higher than that of group C;the level of S-100β protein in group C was significantly higher than that at stage Ti(P<0.05).Compared with Ti,there was no significant change in S-100β protein level in group R at T6,and there was a significant difference compared with group C at T6(P<0.05).Compared with the day before operation(T0),group MMSE scored at group T6.25.40±3.21 points and 26.93±2.16 points at 7 days postoperatively(T7)were significantly decreased(P<0.05);T6 and T7 points in the R group were 27.37±1.75 points and 27.80±1.71 points,respectively,and the MMSE score was related to the preoperative phase.There was no significant difference between the two groups(P>0.05),but the MMSE scores at T6 and T7 were significantly lower in group C than in group R(P<0.05).[Conclusion]Remote ischemic preconditioning(RIPC)can improve oxygenation of lung tissue in elderly patients during OLV,reduce inflammatory response,maintain cerebral oxygen metabolism in a better equilibrium,and stabilize S by maintaining cerebral oxygen metabolism balance between supply and demand.S-100β protein level helps to protect early postoperative cognitive function in elderly patients with OLV. |
