Effect Of Different Airway Pressures PEEP Incremental Lung Recruitment On Intraoperative Circulation And Postoperative Complications In Elderly Patients Undergoing Laparoscopic Colorectal Cancer Surgery

Objective:To investigate the effect of different pressure PEEP incremental lung recruitment on intraoperative circulation and postoperative complications in elderly patients undergoing laparoscopic colorectal cancer surgery.Methods:During the period from May 2022 to December 2022 in the People’s Hospital of Inner Mongolia Autonomous Region,60 patients,aged 65-75,with ASA grade I-III and BMI18-25kg/m²,There were no respiratory diseases and cardiovascular diseases before operation.By using digital random table method,patients were randomly divided into 3 groups（n=20）:PEEP airway pressure（Ppeak）reached35cm H₂O,B in group A,30cm H₂O,C in group B and 25cm H₂O in group C.After general anesthesia induction intubation,the three groups of patients underwent PEEP incremental lung recruitment at 60min and 120min of mechanical ventilation respectively.The patients in the three groups reached the peak pressure at（T0）before induction,（T1）5min after the start of mechanical ventilation,（T2）60min after the start of mechanical ventilation,（T3）after the first lung recruitment,（T4）5min after the first lung recruitment,（T5）after mechanical ventilation for 120min,（T6）after the second lung recruitment,（T7）5min minutes after the second lung recruitment,Mean arterial pressure（Mean artery pressure,MAP）,heart rate（Heart rate,HR）were recorded.Tidal volume（VT）,PEEP and Ppeak were recorded in three groups of patients at T1,T2,T4,T5,T7 and T8 respectively.The arterial carbon dioxide partial pressure、arterial oxygen partial pressure and oxygenation index were recorded at T0and T7.The expressions of IL-8 and TNF-a in peripheral venous serum of patients in the three groups were detected at T0 and（T9）30min after extubation.The common pulmonary complications were recorded 24 hours after operation（T10）.Conclusion:（1）Hemodynamic comparison of three groups of patients:Compared with T2,the MAP of the three groups decreased at T3,and the decrease in group A was more obvious,with statistical significance（P<0.05）,Compared with T5,the MAP of the three groups decreased at T6,especially in Group A,with statistical significance（P<0.05）;Intra-group comparison:Compared with T0,the MAP of T2,T3,T4,T5,T6 and T7 in the three groups decreased（P<0.05）;HR at each time point had no significant difference（P>0.05）.（2）Compared with T1,the Ppeak of T2,T4,T5,T7 and T8 in the three groups increased,and the Cdyn decreased,with statistical significance.（P<0.05）;In groups A and B,T2 and T4 were compared,and T5 and T7 were compared,Ppeak decreased and Cdyn increased,the difference was statistically significant.（P<0.05）,there was no statistical significance in group C.At T4,T7 and T8,Ppeak in group A and B was lower than that in group C,Cdyn in group A and B was higher than that in group C（P<0.05）.No significant difference was found between groups A and B in Ppeak and Cdyn（3）Comparison of oxygenation function:At T7,OI and Pa O₂in group C were lower than those in groups A and B（P<0.05）.（4）The postoperative concentrations of IL-8 and TNF-αincreased in all three groups,the difference was statistically significant（P<0.05）.At T9,group C>group A>group B,he difference was statistically significant（P<0.05）.The postoperative pulmonary complications of the three groups were not significantly different（P>0.05）.Conclusion:PEEP=30cm H₂O incremental lung recruitment method has less hemodynamic fluctuation,can improve intraoperative oxygenation and reduce the production of inflammatory factors,which may be a suitable airway pressure for elderly patients undergoing laparoscopic colorectal cancer surgery.