Irreversible electroporation is a fast-growing liver ablation technique. Although safety has been well documented in small ablations, our aim is to assess its safety and feasibility when a large portion of liver is ablated. Eighty-seven mice were subjected to high voltage pulses directly delivered across parallel plate electrodes comprising around 40% of mouse liver. One group consisted in 55 athymic-nude, in which a tumor from the KM12C cell line was grown and the other thirty-two C57-Bl6 non-tumoral mice. Both groups were subsequently divided into subsets according to the delivered field /nstrength (1000V/cm, 2000V/cm) and whether or not they received anti-hyperkalemia therapy. Early mortality (less than 24hours post-IRE) in the 2000V/cm group was observed and revealed considerably higher mean potassium levels. In contrast, the animals subjected to a 2000V/cm field treated with the anti-hyperkalemia therapy had higher survival rates (OR=0.1, 95%CI=0.02–0.32, p<0.001). Early mortality also depended on the electric field magnitude of the IRE protocol, as mice given 1000V/cm survived longer than those given 2000V/cm (OR=4.7, 95%CI=1.8–11.8, p=0.001). Our findings suggest that ionic disturbances, mainly due to potassium alterations, should be warned and envisioned when large volume ablations are performed by IRE.

This research was supported by the Spanish “Plan Estatal de Investigación, Desarrollo e Innovación Orientada/na los Retos de la Sociedad” under Grant TEC2014–52383-C3 (TEC2014-52383-C3-1-R, TEC2014-52383-C3-/n2-R, and TEC2014-52383-C3-3-R), and by the Spanish “Plan Nacional de I + D + i del Ministerio de Ciencia e/nInnovación” under Grants TEC2011-27133-C02 and TEC2010-17285.