BACKGROUND Intraoperative blood loss has been shown to be an important factor correlating with morbidity and mortality in liver surgery. A 5-cm long instrument with variably deployable metal electrodes using in-line radiofrequency ablation (ILRFA) energy was used for hepatic transection in an attempt to reduce bleeding. METHODS Eight patients underwent liver resection. At each resection, half the resection was performed with ILRFA and the other half was performed with an ultrasonic aspirator alone. Blood loss was measured for each mode of resection. RESULTS The mean blood loss using ILRFA was 6.5 (+/-3.7) mL/cm(2) compared with 20.4 (+/-8.7) mL/cm(2) by using the ultrasonic aspirator (P = .004). CONCLUSIONS In-line radiofrequency ablation reduced bleeding during hepatic parenchymal transection when compared with the ultrasonic aspirator.