The Significance Of End-tidal Carbon Dioxide Pressure And Arterial Carbon Dioxide Pressure Monitoring In Retroperitoneoscopyic Surgery

Objective:To study the significance of end-tidal carbon dioxide pressure and arterial carbon dioxide pressure monitoring in retroperitoneoscopyic surgery.Methods:72 patients scheduled for retroperitonesocopy were retrospective studied, ASAâ… -â…¢.50 cases of adrenal surgery, kidney surgery in 22 cases. The patients were divided into two groups according to the value of PaCO2, Group A:60 patients, PaCCO2 was not surpassed 60 mmHg after CO2 insufflation. Group B:12 patients, PaCO2 was surpassed 60 mmHg at one or more time after CO2 insufflation.All patients received intravenous anesthesia with endotracheal intubation. After orotracheal intubation, the lung of all patients were ventilated with intermittent positive pressure ventilation, tidal volume of 8ml/kg, respiratory rate of 12 per minute and inspiration-expiration time ratio of 1:2. Before pneumoperitoneum (T1) and 30 (T2),60 (T3),90min(T4) after CO2 insufflation the arterial blood gas was analysed and PaCO2,PETCO2 were recorded, Pa-ETCO2 was calculated at each time according PaCO2 and PETCO2. patients were occurred with or without subcutaneous emphysema.Results:General information of patients (age and weight) was no significant difference in two groups(P> 0.05),3 patients were body mass index> 30kg/m2,3 patients were mild to moderate obstructive ventilatory defect showed in preoperative pulmonary function tests,6 patients were occurred subcutaneous emphysema in surgery,All surgeries were over successfully. Group B compared with group A:At T1 and T2, PaCO2, PETCO2 and Pa-ETCO2 in group B were no significant difference compared with group A (P> 0.05). At T3 and T4, three parameters of monitoring in group B were significant differences compared with group A (P<0.05). In group of comparison:In group A, T2-4 compared with T1, PaCO2, PETCO2, Pa-ETCO2 were statistically significant (P<0.05). T3 compared with T2, T4 compared with T3, T4 compared with T2, three parameters of monitoring were no significant difference (P> 0.05). In group B, T2-4 compared with T1, PaCO2, PETCO2, Pa-ETCO2 were statistically significant (P<0.05 or P<0.01). PaCO2 and PETCO2 were gradually increased with pneumoperitoneum time, T3 compared with T2, T4 compared with T3, T4 compared with T2, PaCO2 was significantly different (P<0.05), T4 compared with T2, PETCO2 was significantly different (P<0.05).Conclusion:PaCO2, PETCO2, Pa-ETCO2 were increased after CO2 insufflation during retroperitoneoscopyic surgery, PETCO2 Can not accurately estimate PaCO2. Particularly for these patients, they were body mass index> 30kg/m2, mild to moderate obstructive ventilatory defect showed in preoperative pulmonary function tests, occurred subcutaneous emphysema in surgery, PaCO2 and PETCO2 were progressively increased with time after CO2 insufflation. PETCO2 monitoring couldn't meet the need of monitoring, Arterial gas analysis monitoring PaCO2 should be used to help in retroperitoneoscopyic.