A Study Of Appropriate Tidal Volume And PEEP With Volume Controlled Ventilation Mode In Laparoscopic Cholecystectomy

Objective:By comparing various mechanical ventilation strategies,the optimal tidal volume combined with PEEP was found to minimize the physiological disturbance and satisfy the patients'oxygenation in the volume-controlled ventilation mode of laparoscopic cholecystectomy.Methods:216 patients undergoing laparoscopic cholecystectomy were selected.In the experiment,tidal volume was divided into three groups:V1group?6ml/kg?,V₂ group?8ml/kg?,V₂ group?8ml/kg?,V₃ group?10ml/kg?,V₁ group was subdivided into four groups:V_1.1 group?0 cmH₂OPEEP?),V_1.2group?5cmH₂OPEEP?,V_1.3 group?8cmH₂OPEEP?,V_1.4 group?10cmH₂OPEEP?.By analogy,the V₂ group was subdivided into V_2.1 group?0cmH₂OPEEP?,V_2.2 group?5cmH₂OPEEP?,V2.3 group?8 cmH₂OPEEP?,V_2.4 group?10 cmH₂OPEEP?,V₃ group was divided into V_3.1 group?0cmH₂OPEEP?),V_3.2 group?5 cmH₂OPEEP?,V_3.3 group?8 cmH₂OPEEP?,V_3.4 group?10 cmH₂OPEEP?.The subjects were randomly divided into the above groups,18 in each group.Total intravenous anesthesia was used.All anesthetics were discontinued after the operation.Respiratory and circulatory indexes were recorded before establishment of pneumoperitoneum?T₀?,immediately after establishment of pneumoperitoneum?T₁?,immediately after change of position?T₂?,30 minutes after establishment of pneumoperitoneum?T₃?,immediately after pneumoperitoneum?T₄?,and 15minutes after extubation?T₅?.Meanwhile,arterial blood gas was collected at T₀,T₃ and T₅ to analyze and record the results.Results:In group V₁,the PaO₂ of PEEP groups was higher than that of non-PEEP groups?P<0.05?,and there was no significant difference between PEEP groups.There was no significant difference in PaO₂ between PEEP group and non-PEEP group in group V₂ and V₃.After the establishment of pneumoperitoneum,PaCO₂ increased gradually,and compliance decreased gradually.The compliance of PEEP group was higher than that of non-PEEP group?P<0.05?.In the V₁ group,the compliance of the 8cmH₂O PEEP group and the 10cmH₂O PEEP group was not statistically different,and the compliance with 5cmH₂O PEEP was statistically different.In the V₂ and V₃ groups,there was a statistical difference between the 5cmH₂O PEEP group and the 10cmH₂O PEEP group;after the end of pneumoperitoneum,the compliance of PEEP group was higher than that of non-PEEP group?P<0.05?.After pneumoperitoneum was established,Ppeak and Pplat increased gradually,and PEEP group was higher than non-PEEP group?P<0.05?.In V₁ group,there were statistical differences in Ppeak and Pplat between8cmH2O PEEP and 10cmH₂O PEEP at T₁-T₃,10cmH₂O PEEP group had the highest Ppeak and Pplat,and 10 cmH₂O PEEP group had the highest Ppeak and Pplat,while 10cmH₂O PEEP group had the highest Ppeak and Pplat at T₁and T₄,and 10cmH₂O PEEP group had the highest Pplat,while 10cmH₂O PEEP group had the highest Pplat in the whole pneumoperitoneum.In the V₃group,there were statistical differences in Ppeak and Pplat between 5cmH₂O PEEP and 8cmH₂O PEEP at T₁;at T₄,there were statistical differences between PEEP and 8cmH₂O PEEP.The driving pressure of group PEEP was lower than that of non-PEEP group,and the difference was statistically significant.In V₁ group,the driving pressure of 8cmH₂O PEEP group was the smallest,and there was statistical difference between 8cmH₂O PEEP group and 5cmH₂O PEEP,10cmH₂O PEEP group;in V₂ group,the driving pressure of 10cmH₂O PEEP group was the smallest,but there was no statistical difference between 5cmH₂O PEEP group and 10cmH₂O PEEP group;in V₃ group,there was statistical difference between 5cmH₂O PEEP group and 10cmH₂O PEEP group,but there was no statistical difference between 8cmH₂O PEEP group and 10cmH₂O PEEP group.By comparingV₁,V₂ and V₃ groups,8cmH₂O PEEP group was better than 0cmH₂O PEEP group,5cmH₂O PEEP group and 10cmH₂O PEEP group.By comparing V_1.3,V_2.3 and V_3.3 groups,it was observed that there were statistical differences in Ppeak,Pplat and driving pressure among the three groups,and V_3.3 was the highest and V_1.3.3 was the lowest.Conclusions:Compared with the traditional tidal volume,small tidal volume plus PEEP protective ventilation strategy for elective laparoscopic cholecystectomy patients have greater advantages.For patients undergoing elective laparoscopic cholecystectomy,we recommend that the mechanical ventilation parameters be set to 6ml/kg+8cmH₂OPEEP.In this mode,the peak airway pressure,plateau pressure and driving pressure are smaller.This strategy has little physiological impact on patients.