Abstract

BACKGROUND
Peritoneal CO2 insufflation results in elevation of PaCO2 and decreased respiratory compliance. Respiratory mechanics can be measured with flow interrupter technique. This study was designed to evaluate the effect of increased intra-abdominal pressure and positions on respiratory mechanics during laparoscopic surgery.
METHODS
Female patients undergoing cholecystectomy (10 degrees head-up group, n=9) and gynecologic operation (10 degrees head-down group, n=9) under laparoscopy were studied. The upper limit of intra-abdonimal pressure was set to 12 mmHg. We measured airway flow and airway pressure of patients at preoperation, during insufflation, during positioning, and postoperation. Respiratory data were obtained from D-lite(R)sensor on-line.
RESULTS
After increased intra-abdominal pressure and positioning, dynamic compliances in both groups were significantly decreased by 31~35%, static compliances by 39~43%. There was no difference of compliance between positions. The elastic tissue resistance of head-up group was significantly elevated compared with after operation. After operation, the respiratory parameters returned nearly to control levels.
CONCLUSIONS
This result suggests that the respiratory mechanics should be monitored under laparoscopy continuously. Further studies on clinical condition such as ascites, hemorrhage, and pregnancy were needed.

• Keywords: Head-down;Head-up;Intra-abdominal pressure;Laparoscopic surgery;Respiratory mechanics;