title: Residual right portal branch flow after first-step ALPPS: artifact or homeostatic response?
abstract: OBJECTIVE
  Mutual interactions between portal vein and hepatic artery can be documented during hepatobiliary surgery. Associating Liver Partition and Portal Vein Ligation for Staged Hepatectomy (ALPPS) is a recently introduced surgical technique which can also represent a unique living human model to investigate intrahepatic blood circulation. We report three consecutive cases in which a residual right portal branch flow was clearly detectable after first-step ALPPS, and try to further investigate this unexpected finding with intraoperative clamping tests.
  
  
  METHODS
  Every patient was evaluated with CT scan 7 days after first-step ALPPS and Intraoperative Doppler Ultrasonography (IOUS) at both steps of the procedure.
  
  
  RESULTS
  In every patient, CT scan and second-step IOUS demonstrated a clear hepatopetal flow distally to the divided right portal branch. The flow was present after right biliary duct clamping and stopped after right total hilar clamping as well as after right hepatic artery occlusion.
  
  
  CONCLUSIONS
  Neither cross-portal circulation between the two hemilivers nor trans-sinusoidal backflow from the hepatic veins can explain these findings, which are rather consistent with a refilling of the occluded portal branch through the opening of intrahepatic arterioportal shunts (APS). APS could represent the simplest homeostatic mechanism that regulate intrahepatic blood flow.
authors.forename: Luciano
authors.initials: L
authors.lastname: De Carlis
authors.forename: Raffaella
authors.initials: R
authors.lastname: Sguinzi
authors.forename: Riccardo
authors.initials: R
authors.lastname: De Carlis
authors.forename: Stefano
authors.initials: S
authors.lastname: Di Sandro
authors.forename: Jacopo
authors.initials: J
authors.lastname: Mangoni
authors.forename: Paolo
authors.initials: P
authors.lastname: Aseni
authors.forename: Alessandro
authors.initials: A
authors.lastname: Giacomoni
authors.forename: Angelo
authors.initials: A
authors.lastname: Vanzulli
mesh_terms: D000368:Aged; D016477:Artifacts; D001650:Bile Duct Neoplasms / Q000473:pathology / Q000601:surgery*; D005260:Female; D006498:Hepatectomy / Q000379:methods*; D006499:Hepatic Artery / Q000503:physiopathology / Q000601:surgery; D006706:Homeostasis; D006801:Humans; D008026:Ligation; D008102:Liver Circulation; D008113:Liver Neoplasms / Q000556:secondary / Q000601:surgery*; D008115:Liver Regeneration; D008297:Male; D008875:Middle Aged; D010690:Phlebography / Q000379:methods; D011169:Portal Vein / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D018608:Ultrasonography, Doppler