Comparison Of Carbon Dioxide Absorption In The Preperitoneal Space And Retroperitoneal Space

Objective:To compare the carbon dioxide（CO₂）absorption in the preperitoneal space and retroperitoneal space during pneumoperitoneum.Methods:Thirty patients undergoing totally extraperitoneal laparoscopic inguinal hernia repair（group E）and other thirty undergoing retroperitoneal laparoscopic renal cystectomy（group R）under general anesthesia were selected.HR、MAP、P_ETCO₂、Peak were recorded and VCO₂ were calculated at six time points.These time points were before CO₂insufflation（T₀）,CO₂ insufflation for 10 minutes（T₁）,30 minutes（T₂）,60 minutes（T₃）,after CO₂deflatingfor10minutes（T₄）andaftertrachealextubationfor10minutes（T₅）.Also,the results of arterial blood gas analysis were recorded before pneumoperitoneum（T₀）and 1 hour after pneumoperitoneum(T_1h).Results:Comparison within the group:Compared with T₀,P_ETCO₂ at T₁^T₄,Peak at T₁^T₃ and VCO₂ at T₂^T₄ were significantly increased（P<0.01）.As for the arterial blood gas index,compared with T₀,pH and Lac at T_1hh were significantly decreased（P<0.01）,and PaCO₂ was significantly increased（P<0.01）.Comparison between groups:Compared with group E,the increase of P_ETCO₂,PaCO₂,and VCO₂ in patients of group R was more obvious（P<0.05）.There was no significant difference in HR and MAP between the two groups before and after pneumoperitoneum（P>0.05）.And there was no significant difference in the incidence of postoperative complications（P>0.05）.Conclusion:In laparoscopic surgery with CO₂ pneumoperitoneum,the CO₂ absorption in artificialcavitiescontinuedtoincreaseslowlywiththeprolongationof pneumoperitoneum.And the CO₂ absorption in retroperitoneal space is more significant than in preperitoneal space and it has little effect on the circulatory function.However,the monitoring and management of respiratory function should be further strengthened,and effective measures should be taken to reduce CO₂ absorption and reduce CO₂-related complications to the body.