title: The effects of intraoperative lung protective ventilation with positive end-expiratory pressure on blood loss during hepatic resection surgery: A secondary analysis of data from a published randomised control trial (IMPROVE).
abstract: BACKGROUND
  During high-risk abdominal surgery the use of a multi-faceted lung protective ventilation strategy composed of low tidal volumes, positive end-expiratory pressure (PEEP) and recruitment manoeuvres, has been shown to improve clinical outcomes. It has been speculated, however, that mechanical ventilation using PEEP might increase intraoperative bleeding during liver resection.
  
  
  OBJECTIVE
  To study the impact of mechanical ventilation with PEEP on bleeding during hepatectomy.
  
  
  METHODS
  Post-hoc analysis of a randomised controlled trial.
  
  
  METHODS
  Seven French university teaching hospitals from January 2011 to August 2012.
  
  
  METHODS
  Patients scheduled for liver resection surgery.
  
  
  METHODS
  In the Intraoperative Protective Ventilation trial, patients scheduled for major abdominal surgery were randomly assigned to mechanical ventilation using low tidal volume, PEEP between 6 and 8  cmH2O and recruitment manoeuvres (lung protective ventilation strategy) or higher tidal volume, zero PEEP and no recruitment manoeuvres (non-protective ventilation strategy).
  
  
  METHODS
  The primary endpoint was intraoperative blood loss volume.
  
  
  RESULTS
  A total of 79 (19.8%) patients underwent liver resections (41 in the lung protective and 38 in the non-protective group). The median (interquartile range) amount of intraoperative blood loss was 500 (200 to 800)  ml and 275 (125 to 800)  ml in the non-protective and lung protective ventilation groups, respectively (P = 0.47). Fourteen (35.0%) and eight (21.5%) patients were transfused in the non-protective and lung protective groups, respectively (P = 0.17), without a statistically significant difference in the median (interquartile range) number of red blood cells units transfused [2.5 (2 to 4) units and 3 (2 to 6) units in the two groups, respectively; P = 0.54].
  
  
  CONCLUSIONS
  During hepatic surgery, mechanical ventilation using PEEP within a multi-faceted lung protective strategy was not associated with increased bleeding compared with non-protective ventilation using zero PEEP.
  
  
  BACKGROUND
  The current study was not registered. The original Intraoperative Protective Ventilation study was registered on clinicaltrials.gov; number NCT01282996.
authors.affiliation: From the Department of Intensive Care and Anesthesiology, AP-HP, Hôpital Beaujon, Hôpitaux Universitaires Paris Nord Val de Seine, Paris (AN, ME, CPB); Department of Anesthesiology and Critical Care Medicine, Estaing Hospital, University Teaching Hospital of Clermont-Ferrand, and R2D2 unit, EA 7281, Clermont-Ferrand (EF); Department of Anesthesiology and Critical Care Medicine, Hôpital Saint-Eloi, University Teaching Hospital of Montpellier and INSERM U-1046, Montpellier (SJ); University Hospital of Clermont-Ferrand, Biostatistics Unit (DRCI), Clermont-Ferrand (BP); Department of Anesthesiology and Critical care Medicine, Hôpital Tenon, AP-HP (EM, OS); Department of Anesthesiology and Critical care Medicine, Hôpital Saint Antoine, AP-HP, Université Pierre et Marie Curie PARIS VI (MB); University Paris Diderot, Sorbonne Paris Cité (CPB); and INSERM U773, CRB3, Paris, France (CPB).
authors.forename: Arthur
authors.initials: A
authors.lastname: Neuschwander
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Futier
authors.forename: Samir
authors.initials: S
authors.lastname: Jaber
authors.forename: Bruno
authors.initials: B
authors.lastname: Pereira
authors.forename: Mathilde
authors.initials: M
authors.lastname: Eurin
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Marret
authors.forename: Olga
authors.initials: O
authors.lastname: Szymkewicz
authors.forename: Marc
authors.initials: M
authors.lastname: Beaussier
authors.forename: Catherine
authors.initials: C
authors.lastname: Paugam-Burtz
mesh_terms: D000368:Aged; D016063:Blood Loss, Surgical / Q000517:prevention & control*; D001803:Blood Transfusion; D004311:Double-Blind Method; D005260:Female; D005602:France; D006498:Hepatectomy / Q000009:adverse effects*; D006785:Hospitals, University; D006801:Humans; D008297:Male; D008875:Middle Aged; D011175:Positive-Pressure Respiration / Q000009:adverse effects*; D012307:Risk Factors; D013990:Tidal Volume; D013997:Time Factors; D016896:Treatment Outcome; D055397:Ventilator-Induced Lung Injury / Q000517:prevention & control*