title: Correlation between blood loss and inferior vena caval pressure during liver resection.
abstract: BACKGROUND
  Blood loss and transfusion requirement are major determinants of mortality and morbidity following liver resection. This study was prompted by the observation that blood loss was excessive when the inferior vena cava (IVC) was distended, and determined whether a correlation exists between blood loss and pressure within the IVC during liver resection.
  
  
  METHODS
  A 6-month prospective study was conducted on 20 consecutive patients undergoing liver resection in which two variables were measured, the pressure within the retrohepatic part of the IVC and blood loss during resection.
  
  
  RESULTS
  It was observed that when the caval pressure was less than 6 mmHg the operating field was almost bloodless (mean blood loss 363 (range 305-465) ml). When the caval pressure was between 6 and 12 mmHg the liver became congested and bleeding from the liver surface became significantly greater (1259 (range 415-1789) ml). When caval pressure was greater than 13 mmHg bleeding became excessive (2703 (range 2360-3450) ml). Correlation between blood loss and caval pressure was strong (Pearson correlation coefficient 0.93, P < 0.001).
  
  
  CONCLUSIONS
  This study suggests that one of the keys to decreasing blood loss and transfusion requirement during liver resection is to lower pressure within the IVC.
authors.affiliation: Department of Surgery, Fazakerley Hospital, Aintree Hospitals Trust, Liverpool, UK.
authors.forename: M
authors.initials: M
authors.lastname: Johnson
authors.forename: R
authors.initials: R
authors.lastname: Mannar
authors.forename: A V
authors.initials: AV
authors.lastname: Wu
mesh_terms: D016063:Blood Loss, Surgical; D001794:Blood Pressure; D006801:Humans; D008099:Liver / Q000601:surgery*; D011446:Prospective Studies; D014682:Vena Cava, Inferior / Q000503:physiopathology*