VENOUS HEMODYNAMIC-CHANGES DURING LAPAROSCOPIC CHOLECYSTECTOMY

Virchow's triad of venous stasis, vessel wall damage, and hypercoagula bility cites three factors that predispose to the formation of venous thrombosis. The pneumoperitoneum created during laparoscopic surgery r esults in an intraabdominal pressure that exceeds the pressure of veno us blood return from the legs. This may alter venous hemodynamics enou gh to result in venous stasis in the legs, thus increasing the risk of thrombus formation. Duplex ultrasound was used to measure the diamete r and venous flow volume of the common femoral vein during laparoscopi c cholecystectomy. Measurements were obtained at three different times : after induction of anesthesia but prior to creation of pneumoperiton eum, during pneumoperitoneum, and after abdominal deflation but prior to reversal of anesthesia. After insufflation of the abdomen, the mean cross-sectional area of the common femoral vein increased (0.83 to 1. 15 cm(2); p = 0.0024) and the venous flow decreased (11.00 to 6.06 cm( 3)/sec; p = 0.0008). After deflation of the abdomen, there was no sign ificant change in cross-sectional area of the common femoral vein, but there was an increase in venous flow (6.06 to 9.94 cm(3)/sec; p = 0.0 005). Abdominal insufflation during laparoscopic cholecystectomy resul ts in dilation of and decreased flow in the common femoral vein. After deflation of the abdomen, flow in the vein returns to baseline levels .