title: Partial clamping of the infrahepatic inferior vena cava for blood loss reduction during anatomic liver resection: A prospective, randomized, controlled trial.
abstract: Anatomic liver resection often requires the exposure of the hepatic vein on its cut surface, and theoretically, lower central venous pressure aids in reducing blood loss. Therefore, we hypothesized that manipulating the central venous pressure by partially clamping the infrahepatic inferior vena cava might reduce blood loss during anatomic liver resection.
  
  
  
  Patients undergoing planned anatomic liver resections were allocated randomly to the partial infrahepatic inferior vena cava clamping or nonclamping groups. Hepatocellular carcinoma diagnosis was set as a stratifying factor because of underlying liver disease. The primary outcome was intraoperative blood loss. Secondary outcomes were intraoperative parameters and postoperative safety. We submitted the detailed protocol to the University Hospital Medical Information Network Clinical Trials Registry (Registration number: UMIN000007339 [http://www.umin.ac.jp.]).
  
  
  
  Between August 2011 and August 2015, 90 patients were allocated randomly. Both groups had comparable baseline characteristics. The central venous pressure was reduced from 6.0 to 3.0 mm Hg in the partial inferior vena cava clamping group without any complications (P < .001). Among all eligible patients, median values for total blood loss, blood loss during liver resection, and blood loss per transected area (nonclamping vs clamping groups) were 360 vs 350 mL (P = .19), 310 vs 250 mL (P = .045), and 4.9 vs 3.6 mL/cm2(P = .15), respectively. However, among the subgroup of patients with hepatocellular carcinoma, these median values were 460 vs 290 mL (P = .06), 365 vs 217 mL (P = .007), and 5.2 vs 3.6 mL/cm2(P = .03), respectively. Morbidities and laboratory data were comparable in both groups.
  
  
  
  Partial infrahepatic inferior vena cava clamping safely reduced central venous pressure and may reduce blood loss in patients with hepatocellular carcinoma when central venous pressure is >5 mm Hg at hepatic parenchymal transection.
authors.affiliation: Second Department of Surgery, Wakayama Medical University, Wakayama, Japan.
authors.forename: Masaki
authors.initials: M
authors.lastname: Ueno
authors.affiliation: Second Department of Surgery, Wakayama Medical University, Wakayama, Japan.
authors.forename: Manabu
authors.initials: M
authors.lastname: Kawai
authors.affiliation: Second Department of Surgery, Wakayama Medical University, Wakayama, Japan.
authors.forename: Shinya
authors.initials: S
authors.lastname: Hayami
authors.affiliation: Second Department of Surgery, Wakayama Medical University, Wakayama, Japan.
authors.forename: Seiko
authors.initials: S
authors.lastname: Hirono
authors.affiliation: Second Department of Surgery, Wakayama Medical University, Wakayama, Japan.
authors.forename: Ken-Ichi
authors.initials: KI
authors.lastname: Okada
authors.affiliation: Second Department of Surgery, Wakayama Medical University, Wakayama, Japan.
authors.forename: Kazuhisa
authors.initials: K
authors.lastname: Uchiyama
authors.affiliation: Second Department of Surgery, Wakayama Medical University, Wakayama, Japan. Electronic address: h-yamaue@wakayama-med.ac.jp.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Yamaue
mesh_terms: D000368:Aged; D016063:Blood Loss, Surgical / Q000517:prevention & control*; D006528:Carcinoma, Hepatocellular / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D002496:Central Venous Pressure; D003250:Constriction; D005260:Female; D005500:Follow-Up Studies; D006498:Hepatectomy / Q000379:methods* / Q000401:mortality; D006503:Hepatic Veins / Q000601:surgery; D006801:Humans; D008113:Liver Neoplasms / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012016:Reference Values; D018570:Risk Assessment; D015996:Survival Rate; D016896:Treatment Outcome; D014682:Vena Cava, Inferior / Q000601:surgery*