Trial Information

The Effect of Different I:E Ratio on Gas Exchange of Patients Undergoing Gynecologic Laparoscopic Surgery With Trendelenburg Position

In patients undergoing gynecologic laparoscopic surgery with trendelenburg position, the
disturbance of pulmonary gas exchange frequently occurs due to high intra-abdominal
pressure. During the laparoscopic surgery with abdominal gas insufflation, gas exchange
disturbance such as CO2 retention, hypoxemia occurs in addition to high plateau airway
pressure. The usual strategy against these kinds of problem is pressure-controlled
ventilation. However, the gas exchange problem especially CO2 retention can not be solved in
some cases. The inverse-ratio ventilation (IRV), which prolongs the inspiratory time greater
than expiratory time, can be applied for adult respiratory distress syndrome. The efficacy
of IRV is to improve gas-exchange status by increasing mean airway pressure and alveolar
recruitment. There have been several clinical investigations which applied IRV during
general anesthesia. However, there have been debates about the effect of IRV during general
anesthesia. Therefore, we tried to apply the IRV for subjects undergoing laparoscopic
surgery, and evaluate the effect of different I:E ratio on the pulmonary gas exchange and
respiratory mechanics.