Effect of bypass flow rate of portosystemic bypass on the visceral organs in acute portal vein occlusion

Research Project

Project/Area Number	61570657
Research Category	Grant-in-Aid for General Scientific Research (C)
Allocation Type	Single-year Grants
Research Field	Digestive surgery
Research Institution	Jichi Medical School
Principal Investigator	KASAHARA Kogorou Assistant professor, Department of Surgery, Jichi Medical School, 医学部, 助教授 (30049035)
Co-Investigator(Kenkyū-buntansha)	FUKUMOTO Takashi Assistant, Department of Surgery,Jichi Medical School, 医学部, 助手 (70189976)
Project Period (FY)	1986 – 1987
Project Status	Completed (Fiscal Year 1987)
Budget Amount *help	¥2,000,000 (Direct Cost: ¥2,000,000) Fiscal Year 1987: ¥800,000 (Direct Cost: ¥800,000) Fiscal Year 1986: ¥1,200,000 (Direct Cost: ¥1,200,000)
Keywords	Acute portal vein occlusion / portosystemic bypass / anti thrombogenic catheter / バイパス流量
Research Abstract	The object of this study was to determine the critical flow rate (BFR) of the portosystemic bypass, using heparin coated catheter Anthrone, during acute portal vein occlusion (PVO). BFR was controlled at 10% (Group 1) , 30% (Group 2), 50% (Group 3) of the portal flow in the individual experimental groups of anesthetized dogs. Hemodynamic and biochemical changes were observed during 2 hours in each group. With decreased BFR, portal venous pressure (P_<pv>) increased, with 47.1 mmHg in Group 1 and 26.8 mmHg in Group 2, and superior mesenteric arterial flow (F_<sma>) decreased remarkably in both Group 1 and Group 2. However, P_<sma> showed negligible changes in Group 3. Thus, negative correlation between BFR and P_<pv> (r=-0.911, P<0.0001), and positive correlation between BFR and F_<sma> (r=0.875, P<0.0001) were found respectively. With decreased BFR, portal venous blood hematocrit increased, with 54.5% in Group 1 and 50.3% in Group 2. Following 2 hours PVO, pH levels of portal venous blood were reduced, with 7.210 in Group 1 and 7.337 in Group 2. CPK-BB levels of portal venous blood correlated well to the degree of intestinal insultation. In conclusions, the critical BFR must be between 10% and 30% of portal flow for life sustaining up to 2 hours PVO, and 50% BFR is sufficient enough in more than 2 hours PVO, in the aspect of mesenteric organ insultation.