Effects of CO_2 pneumoperitoneum on blood pressure,heart rate and depletion rate of CO_2 in the patients undergoing retroperitoneoscopic operation

Objective To observe the effects of CO2 pneumoperitoneum on blood pressure, heart rate (HR) and depletion rate of CO2 in patients undergoing retroperitoneoscopic operation. Methods Eighty-five patients undergone selective operation were involved in present study. Of them 45 underwent radical resection of kidney cancer with retroperitoneoscopy (group A), and 40 underwent laparoscopic hysterectomy or hysterectomy and removal of bilateral appendages (group B). The HR, mean arterial pressure (MAP), central venous pressure (CVP), and arterial carbon dioxide partial pressure (PaCO2) of patients in both groups were monitored and recorded before pneumoperitoneum (T1) and 15min (T2), 30min (T3), 45min (T4) and 60min (T5) after pneumoperitoneum. The depletion of CO2 in different time point of operation was calculated based on formula. Results HR, MAP and CVP were significantly increased after pneumoperitoneum than before pneumoperitoneum in both groups (P0.05), while no significant difference was found in HR, MAP and CVP at each time point between the two groups (P0.05). PaCO2 and CO2 depletion rate was significantly increased after pneumoperitoneum than pre-pneumoperitoneum in both groups (P0.05), while no significant difference existed in PaCO2 and CO2 depletion rate between the two groups at T1, T2 and T3 time points (P0.05). Compared with group B, the PaCO2 and CO2 depletion rate in group A increased obviously at T4 and T5 time point (P0.05). Conclutions CO2 pneumoperitoneum has certain effect on blood pressure and heart rate of patients undergoing retroperitoneoscopic and laparoscopic operations. However, retroperitoneoscopic operation may induce higher PaCO2 and hypercapnia than laparoscopic operation. Monitoring of arterial carbon dioxide pressure should be strengthened during these operations.