Compliance-guided Individualized PEEP On The Effect Of Postoperative Atelectasis In Patients With Pneumoperitoneum-Trendelenburg Position

Objective:To study the effect of compliance-guided individualized PEEP on postoperative atelectasis in patients with pneumoperitoneum-Trendelenburg position.Methods:From June 2019 to June 2020,70 patients who underwent general anesthesia Trendelenburg position laparoscopic surgery in our hospital were selected,ASA gradeⅠ～Ⅱ,age 40-70 years old,random number table method was used to divide the patients into the conventional group（group C）and individualized group（group P）,35 cases in each group.After conventional anesthesia induction,the two groups of patients were in volume-controlled ventilation mode,with a tidal volume of 6ml/kg（standard body weight）,a respiratory rate of 12-15 breaths/min,and maintaining Pet CO₂ at 35～45mm Hg（1mm Hg=0.133KPa）.In group C: after tracheal intubation,we performed PEEP titration under the guidance of dynamic lung compliance,after the titration was completed,setting PEEP=5cm H₂O（1cm H₂O=0.098 k Pa）to maintain ventilation,and after pneumoperitoneum-Trendelenburg position,PEEP was titrated again,then setting PEEP=5cm H₂O to maintain ventilation,when returning to the supine position,we titrated PEEP and continued to set PEEP=5cm H₂O to maintain ventilation until extubation.In group P:after tracheal intubation,we titrated individualized PEEP1 to maintain ventilation,after pneumoperitoneum-Trendelenburg position,we titrated individualized PEEP2 to maintain ventilation,and after returning to the supine position,we titrated individualized PEEP3 again to maintain ventilation until extubation.Both groups of patients underwent lung recruitment every 40 minutes during the pneumoperitoneum-Trendelenburg position.The gender,age,BMI,ASA classification,pneumoperitoneum-Trendelenburg posture maintenance time,operation time,intraoperative blood loss,fluid supplementation,numerical rating scale and other information of the two groups were recorded.The two groups recorded the establishment of invasive blood pressure immediately（T₀）,10 minutes after intubation setting PEEP（T₁）,pneumoperitoneum-Trendelenburg position setting 30min（T₂）,90min（T₃）,150min（T₄）,and restoring supine position set the relevant indicators for 10 minutes after PEEP（T₅）and 30 minutes after extubation（T₆）.Record the PEEP values of the two groups of patients at T₁,T₂,and T₅;To record the blood gas analysis results of the two groups of patients at T₀-6,calculate and record the oxygenation index（OI）;record the Cdyn of the two groups of patients at T₁-5;Computed tomography technology was used to diagnose atelectasis,and the incidence and area of T₆ atelectasis of two groups of patients were recorded.The mean arterial pressure and heart rate changes of the two groups of patients before,during,and 2 minutes after the PEEP titration were recorded.Results:1.There were no significant difference in gender,age,BMI,ASA classification,operation type,pneumoperitoneum-Trendelenburg posture maintenance time,operation time,intraoperative blood loss,and fluid supplementation,numerical rating scale and vasoactive drug use between the two groups of patients（P>0.05）.2.Compared with group C,the PEEP value of patients in group P was significantly higher at T₂,and the difference was statistically significant（P<0.05）.3.Compared with group C,patients in group P had a significant increase in OI at T₃-6moment,and the difference was statistically significant（P<0.05）;compared with T₀,patients in the two groups had a significant decrease in OI at T₂-6,and the difference was statistically significant Scientific significance（P<0.05）;Compared with T₃,the OI of patients in group C was significantly reduced at T₄,and the difference was statistically significant（P<0.05）.4.Compared with group C,the Cdyn of patients in group P was significantly increased at T₃-5 moment,and the difference was statistically significant（P<0.05）;compared with T₁,the Cdyn of the two groups of patients at T₃-4 was significantly lower,the difference was statistically significant（P<0.05）;compared with T₁ moment,the Cdyn of group C patients at T₅ moment was significantly lower,the difference was statistically significant（P<0.05）;compared with T₃,group C patients Cdyn at T₄ moment was significantly reduced,and the difference was statistically significant（P<0.05）.5.There was no significant difference in the incidence of postoperative atelectasis between the two groups（P>0.05）;compared with group C In comparison,the area of postoperative atelectasis in group P was significantly reduced,and the difference was statistically significant（P<0.05）6.The comparison of MAP and HR between the two groups of patients before,during and after PEEP titration was not statistically significant（P >0.05）.Conclusions:Lung compliance guidance individualized PEEP can reduce the area of ??postoperative atelectasis in patients with pneumoperitoneum-Trendelenburg position,improve the oxygenation function of patients during and after surgery,and improve lung tissue compliance.