Hepatic radiofrequency ablation using perfusion electrodes in a pig model: Effect of the Pringle manoeuvre

To assess the influence of the Pringle manoeuvre on volume and geometry of coagulations close to the portal vein using an impedance-controlled radiofrequency ablation system with perfusion electrodes. Twelve pigs were randomly assigned to a control group ( n=6) and a group where the Pringle manoeuvre was applied during ablation ( n=6). One coagulation was made in each animal close to the portal vein. All animals were sacrificed 4 days after ablation, and the livers were removed for gross and histopathologic analysis. Effective coagulation volume in the Pringle group (10.8±5.0 cm 3) was significantly increased ( p=0.03) compared to the control group (4.1±4.1 cm 3). The efficacy ratio, defined as the effective coagulation volume divided by the coagulation volume, was not significantly different in the Pringle group (0.47±0.27) compared to the control group (0.33±0.22). The geometrical centre of the effective coagulation volume did not correspond to the position of the ablation electrode. Thermal damage of the gallbladder was found in three animals, all belonging to the Pringle group. The Pringle manoeuvre was associated with increased effective coagulation volume, but did not significantly influence the predictability of coagulation volume or geometry.