Intraoperative Evaluation of Renal Blood Flow During Laparoscopic Partial Nephrectomy with a Novel Doppler System

Abstract

Hemostasis remains a major challenge associated with laparoscopic renal surgery. We evaluated a cost-effective novel Doppler probe (DP) for assessment of vascular control during laparoscopic partial nephrectomy (LPN). We prospectively collected data during LPN procedures. We documented tumor location and size as well as subjective quality of the hilar dissection. The DP was compared with our standard intraoperative ultrasound system (SUS) for the ability to detect blood flow during hilar dissection and to determine parenchymal ischemia around the tumor after clamping of the renal vessels. Twenty patients underwent LPN by a single surgeon. The mean tumor size was 3.0 cm (range: 1.2-6.3 cm). The times to assess the kidney using the SUS and DP were 68.6 seconds (range: 20-155) and 44.5 seconds (range: 15-180), respectively. Evaluation prior to renal hilar clamping demonstrated the presence of blood flow in all 20 patients (100%) using the SUS and in 17 of 20 (85%) using the DP. Similarly, cessation of blood flow with clamping was documented in 100% of cases with SUS and 85% with DP. Persistent flow was detected by both SUS and DP in two patients requiring further dissection and reclamping. Then, both systems detected the absence of flow before tumor resection. With blood flow interruption confirmation, no patient had significant bleeding at the time of renal parenchymal transection. Intraoperative Doppler ultrasound technologies minimize the risk of significant bleeding during LPN. The DP is a small, simple, effective probe that can be used to assess blood flow interruption to the kidney during laparoscopic renal surgery.