The effect of Trendelenburg position and pneumoperitoneum on regional cerebral oxygen saturation during gynecological laparoscopic surgery

ABSTRACT

BACKGROUND: The Trendelenburg positon and pneumoperitoneum for gynecological laparoscopic surgery can affect cerebral oxygenation through the change of cerebral blood flow. The aim of this study was to evaluate the effect of pneumoperitoneum in a 20degrees Trendelenburg position on regional cerebral oxygen saturation (rSO2). METHODS: Thirty-three female patients of American Society of Anesthesiologists I and II physical status who were undergoing gynecological laparoscopic surgery were enrolled. The rSO2 was monitored with near-infrared spectroscopy (INVOS 5100, Somanetics, Troy, USA). The rSO2, the rate of change in the rSO2, the mean arterial pressure (MAP), heart rate (HR), arterial partial pressure of CO2 (PaCO2) and O2 (PaO2) and end-tidal CO2 (ETCO2) were measured at the following times immediately before the pneumoperitoneum and when placing the patient in the Trendelenburg position (T0), 5, 10, 15 and 20 min after pneumoperitoneum and position change (T1, T2, T3 and T4). RESULTS: Both the right and the left rSO2 increased significantly during pneumoperitoneum in a Trendelenburg position compared with the value at T0 (from T1 to T4) (P < 0.01). The MAP and PaCO2 also increased significantly (P < 0.01). CONCLUSIONS: During the gynecologiccal laproscopioc surgery, cerebral oxygenation, as assessed by rSO2, increased even though the Trendelenburg position and pneumoperitoneum could increase MAP, intracranial pressure and PaCO2, which is considered to be maintained by cerebral autoregulation.