[An experimental study of blood supply to the bile duct under arterio-portal shunting].
The aim of this study is to show whether arterio-portal shunting (APS) improves the blood supply to the bile duct (BD) subsequent to clamping of the arterial blood supply to the liver and the BD. A constant flow APS model was undertaken using beagles. The procedure involved arterio-portal shunting by performing a bypass from the femoral artery to the portal vein (PV) following clamping, assisted by a roller-pump. In one group (Clamp group: n = 6) the shunt flow was kept at 0 ml/min/kg resulting in a reduction in the tissue oxygen saturation level of the BD (%BDISO2) to 28%, and a reduction in the tissue blood flow of the BD (%BDBF) to 17%, of the pre-clamped values. The %BDISO2 and %BDBF were measured by a Tissue-Spectrophotometer and Laser Doppler Flowmeter, respectively. The %BDISO2 and %BDBF decreased rapidly and thereafter were constant. In the other group (Shunt group: n = 6) the shunt flow was kept at 14 ml/min/kg. An increase in the %BDISO2 and %BDBF to 57% and 47%, respectively, was observed. A flow-controlled APS model was also carried out (n = 6). It was found that by periodically increasing the shunt flow from 0 to 7, 14, and 28 ml/min/kg, the %BDISO2, %BDBF, PVSO2 (PV oxygen saturation), and PVF (PV flow) all gradually increased. Statistically, positive correlations were found between the %BDISO2 and PVSO2 (p < 0.0001) and the %BDBF and PVF (p = 0.0002). Twenty additional beagles were divided into a Control group (n = 9) and an APS group (n = 11). In the Control group, a choledochojejunostomy was performed. In the APS group however, in addition to a choledochojejunostomy, one end of the hepatic artery was anastomosed to the side of the PV following ligation of the common hepatic artery, the gastro-duodenal artery and the right gastric artery. The survival ratio, concentration levels of serum total bile acid, total bilirubin, ALP, LAP, and gamma GTP, as well as, histological findings were not significantly different between the Control and the APS group. This study indicates that the blood supply is significantly improved by APS accompanied by clamping of the arterial blood supply to the liver and the BD. This procedure would therefore be useful in the preservation of the bile duct's viability and the bilioenteroanastomosis in clinical practice.
Munemura
T
T
Second Department of Surgery, Hokkaido University School of Medicine, Sapporo, Japan.
D000714:Anastomosis, Surgical; D000818:Animals; D001166:Arteriovenous Shunt, Surgical; D001652:Bile Ducts / Q000098:blood supply*; D003250:Constriction; D004285:Dogs; D005263:Femoral Artery / Q000601:surgery*; D006499:Hepatic Artery; D017078:Laser-Doppler Flowmetry; D011169:Portal Vein / Q000601:surgery*; D012039:Regional Blood Flow; D014022:Tissue Survival