An electrode array that minimizes blood loss for radiofrequency-assisted hepatic resection

Abstract

Hepatic resection is currently the standard treatment for liver cancer. During hepatic resection part of the liver containing the tumor is surgically removed. This type of surgery is accompanied by high blood loss of ~0.6 -1.35 L. Blood loss is associated with increased complication rates, prolonged hospital stay, and reduced patient survival, especially when transfusion is required. Other researchers have suggested using radiofrequency (RF) or microwave ablation to coagulate a tissue slice before resection to reduce blood loss, but conventional devices typically take several hours. We developed a device consisting of a linear array of blade-shaped, 1cm wide radiofrequency (RF) electrodes 1.5 cm apart. Bipolar RF power is applied between pairs of adjacent electrodes, leading to high tissue temperatures between the electrodes that promote coagulation of large vessels (>mm) in the resection plane. Rapid switching of applied power between pairs of adjacent electrodes allows simultaneous heating and coagulation of the entire resection plane within 3 -6 min. In 7 in-vivo trials in a porcine model, resection along a plane pre-coagulated with the device resulted in little (<20 mL) to no blood loss, while coagulating all vessels (up to 4.5 mm diameter in this study). Average treatment time (from placement of the device to transection) was 6.8 ± 0.5 min when 4 electrodes were used, and 11.3 ± 1.2 min when 5-7 electrodes were used. This device may reduce blood-loss related morbidity during resection and reduce treatment time by coagulating all vessels in the resection plane.

Technical Development of a New Semispherical Radiofrequency Bipolar Device (RONJA):Ex VivoandIn VivoStudies

“…The authors developed a device that rapidly coagulated the hepatic resection plane in an animal model. In the authors' opinion the new device shows promise in the effort to reduce blood loss and operating time during liver and kidney resections [ 12 ].…”

Radiofrequency ablation technique in the treatment of liver tumours: review and future issues

“…In particular, FEM models are used to examine the properties of tumour tissues [24,44,45], to understand what affects ablation zone shape and dimensions, to study strategies of RF ablation [9,26,41,46], to investigate algorithms of RF energy deposition [23,25,30] and to develop new RF electrodes [22]. The steps of numerical modelling and simulation are summarized as follows [43]:…”

A surgical device for radiofrequency ablation of large liver tumors

“…A current limitation of the RF tumour ablation is the inability of prevailing devices to treat tumours larger than 5 cm. Previous studies have proposed a new method of rapid switching RF energy between multiple electrodes (Schutt D J et al 2007, Haemmerich D et al 2004, Lee Jr F T et al 2003), which allows the use of multiple RF electrodes simultaneously, reducing the treatment time.…”