Effects Of Different Mechanical Ventilation Methods On Respiratory And P_ETCO₂ In Patients During Gynecological Laparoscopic Operations

Objective: To observe the effects of different mechanical ventilation methods on respiratory mechanics and PETCO2 during gynecological laparoscopic operations.Methods: 80 cases undergoing gynecological laparoscopic operations, Whose ASAⅠ～Ⅱgrade and ages range from 35 to 50 years old and time from 1.5 to 2 hours, were divided into four groups after intracheal intubation. Ventilator parameters were set up VT=8ml/kg and f=12/min. After pneumoperitoneum, ventilator parameters were different: VT=8ml/kg, f=15/min in groupⅠ. VT=8ml/kg, f=12/min in groupⅡ, VT=8ml/kg, f=18/min in groupⅢ. Monitor and record Ppeak, Pplat, lung compliance (CL) and end-tidal CO2 (PETCO2) at 5 minutes after intubation (t1), 15min after trendelenburg position (t2), 30 min after trendelenburg position (t3), 60min after trendelenburg position (t4).Results: The Ppeak and Pplat increase significantly after trendelenburg position and pneumoperitoneum (P<0.05) in four groups of patients, and the groupⅡis more significant (P<0.05). Ppeak and Pplat of four groups increased higher and higher as time passed. But there is no significant differences between t3 and t4, CL of four groups decreased significantly after trendelenburg position and pneumoperitoneum (P<0.05). The groupsⅠ,ⅡandⅣdecreased more significantly than groupⅢafter trendelenburg position and pneumoperitoneum (P<0.05). PETCO2 of four groups increased significantly after trendelenburg position and pneumoperitoneum. In addition, it became higher and higher as time passed (P<0.05). It increased more significantly GroupⅣthan groupⅠ,ⅡandⅢafter trendelenburg position and pneumoperitoneum (P<0.05). But there are no significantly differences between the t3 and t4 time points. Compare among groupsⅠ,Ⅱand III, it increased higher groupsⅡand III at t3 time point. There are no significant differences at the t2, t4 time point.Conclusion: During gynecological laparoscopic operations, different mechanical ventilator parameters can change respiratory mechanics and PETCO2. Before pneumoperitoneum, f is remained at 12times/min and VT 8ml/kg. After pneumoperitoneum, MV is increased by 10% and f is set to 15 times / min, which are a more reasonable breathing parameters.