Background: Portal vein embolization (PVE) of hepatic lobes planned for resection is known to increase the margin of safety in extended hepatic resection. We examined whether volume gain could directly translate into functional gain in the nonembolized hepatic lobes after PVE, using a unique pharmacologic model of hepatic venous isolation and charcoal hemoperfusion.
Methods: Lidocaine hydrochloride (8 mg/kg) was infused over 10 minutes in the portal vein of beagles with hepatic venous isolation and charcoal hemoperfusion, which prevented hepatic recirculation of the drug, and the lidocaine first-pass hepatic extraction ratio (Lid-HER) was determined to assess the selective lobar function of the liver. First, the correlation between Lid-HER and hepatic parenchymal weight of the lidocaine perfusion area was studied. Second, PVE was performed of the left portal branch, and Lid-HER of the nonembolized lobes was determined 1 hour or 2 weeks after PVE.
Results: Hepatic venous isolation and charcoal hemoperfusion reduced (>95%) the postfilter and systemic lidocaine concentrations compared with prefilter concentrations. In the first study, a significant correlation was demonstrated between Lid-HER and hepatic parenchymal weight (P =.0023, r(2) = 0.992). In the second study, both weight ratio of the nonembolized lobes relative to the whole liver and Lid-HER of the nonembolized lobes showed significant increases 2 weeks after PVE of 1.7- and 1.9-fold, respectively.
Conclusions: Hepatic-weight increase paralleled functional increase, as determined by Lid-HER, in the nonembolized hepatic lobes 2 weeks after PVE. Thus, volume change directly translated into functional change in future remnant noncirrhotic liver after PVE.