Fig. 3

Morphologic changes in the hepatic blood flow induced by CO₂-pneumoperitoneum on laparoscopic intraoperative ultrasonography. a Two-dimensional image of portal vein before insufflation of CO₂. b Thirty min after insufflation of CO₂ in the Trendelenburg position, the portal vein showed a marked decrease in the VD from 0.90 cm to 0.64 cm, as well as a marked decrease in MV from 29.50 cm/s to 14.60 cm/s. The calculated BFV decreased from 1126 ml/min to 281 ml/min. c Two-dimensional image of hepatic artery before insufflation of CO₂. d Thirty min after insufflation of CO₂ in the Trendelenburg position, the MV of hepatic artery was significantly increased from 19.2 cm/s to 26.1 cm/s with the VD less affected. The calculated BFV was similar (93 ml/min vs 96 ml/min) to that before insufflation of CO₂. VD vessel diameter, MV mean flow velocity, BFV blood flow volume