title: Effects of prolonged pneumoperitoneum on hepatic perfusion during laparoscopy.
abstract: OBJECTIVE
  To assess the influence of prolonged pneumoperitoneum (PP) on liver function and perfusion in a clinically relevant porcine model of laparoscopic abdominal insufflation.
  
  
  BACKGROUND
  PP during laparoscopic surgery produces increased intra-abdominal pressure, which potentially influences hepatic function and microcirculatory perfusion.
  
  
  METHODS
  Six pigs (49.6 ± 5.8 kg) underwent laparoscopic intra-abdominal insufflation with 14 mm Hg CO2 gas for 6 hours, followed by a recovery period of 6 hours. Two animals were subjected to 25 mm Hg CO2 gas. Hemodynamic parameters were monitored, and damage parameters in the blood were measured to assess liver injury. Liver total blood flow and function were determined by the indocyanine green (ICG) clearance test. Intraoperative hepatic hemodynamics were measured by simultaneous reflectance spectrophotometry (venous oxygen saturation StO2 and relative tissue hemoglobin concentration rHb) and laser Doppler flowmetry (blood flow and flow velocity). Postmortem liver samples were collected for histological evaluation.
  
  
  RESULTS
  A decrease in microvascular perfusion was observed during PP. After 6 hours of PP, ICG clearance increased (P < 0.001), indicating a compensatory improvement of overall liver blood flow resulting in concomitantly improved microcirculatory perfusion (P = 0.024). Minimal parenchymal damage (aspartate aminotransferase) of the liver was seen after 6 hours of PP (P = 0.006), which seemed related to PP pressure. Minor histological damage was observed.
  
  
  CONCLUSIONS
  The liver sustains no additional damage due to prolonged PP during laparoscopic surgery. Our findings suggest that prolonged PP does not hamper liver function or cause liver damage after extended laparoscopic procedures.
authors: Department of Surgery (Surgical Laboratory), Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
authors: Lisette T
authors: LT
authors: Hoekstra
authors: Anthony T
authors: AT
authors: Ruys
authors: Dan M J
authors: DM
authors: Milstein
authors: Gan
authors: G
authors: van Samkar
authors: Mark I
authors: MI
authors: van Berge Henegouwen
authors: Michal
authors: M
authors: Heger
authors: Joanne
authors: J
authors: Verheij
authors: Thomas M
authors: TM
authors: van Gulik
mesh_terms: D000818:Animals; D001784:Blood Gas Analysis; D005260:Female; D006439:Hemodynamics; D010535:Laparoscopy; D008099:Liver / Q000098:blood supply*; D008111:Liver Function Tests; D008833:Microcirculation / Q000502:physiology; D011028:Pneumoperitoneum, Artificial / Q000379:methods; D013552:Swine; D013997:Time Factors