Controlled study of Inline radiofrequency coagulation-assisted partial nephrectomy in sheep.

BACKGROUND: Primary or secondary tumors of kidney often are managed by partial nephrectomy. Intraoperative blood loss can be significant. Laparoscopic partial nephrectomy may be even more challenging. We developed the Inline radiofrequency coagulation (ILRFA) probe for liver surgery. It uses radiofrequency energy to make a linear coagulative plane and considerably reduces bleeding during parenchymal transection. In this stud,y we tested the efficiency of ILRFA in ovine kidney. METHOD: Seven sheep were used in this study. Under general anesthetic, a laparotomy was performed in each sheep. The first two sheep were used as pilot experiments. Five partial nephrectomies were made in the remaining five sheep using ILRFA. As a control, a matching partial nephrectomy was made in each sheep using diathermy and sutures. Blood loss was measured by determining the difference in the weights of dry sponges and blood stained sponges after resection. A paired t test was used to compare the bleeding between the control and the ILRFA technique. RESULTS: The mean blood loss using ILRFA was 33.14 g (SD 17) and 123.43 g (SD 72) in the control group. The bleeding was significantly reduced in the ILRFA group, with a P value of 0.0056. The time taken for applying the ILRFA was 3-4 min. CONCLUSION: We have achieved partial nephrectomy in ovine kidney using radiofrequency energy with significantly reduced blood loss.

Controlled study of in-line ovine spleen transection assisted by radiofrequency ablation.

BACKGROUND: Trauma to the spleen or tumors of the spleen often require total splenectomy for control of hemorrhage. Partial splenectomy is the preferred technique because of the short- and long-term sepsis problems in asplenic patients. Multiple techniques for partial splenectomy have been tried in the past with limited success. The authors designed the in-line radiofrequency ablation (ILRFA) probe for liver surgery. It uses radiofrequency energy to make a linear coagulative plane that allows the parenchyma of solid vascular organs to be divided. In this study, for the first time, the efficiency of ILRFA was tested with the ovine spleen. METHODS: Seven sheep were used for this study. With the sheep under general anesthesia, a laparotomy was performed. The first sheep was used for a pilot study. Eight partial splenectomies were made in the remaining six sheep using ILRFA. For a control, a matching partial splenectomy was made in each sheep using diathermy and sutures. Blood loss was measured by determining the difference in the weights of dry sponges and blood-stained sponges after resection. A paired t test was used to compare the bleeding between the control and the ILRFA techniques. RESULTS: The mean blood loss was 33.14 +/- 17 g using ILRFA and 123.43 +/- 72 g in the control group. The bleeding was significantly reduced in the ILRFA group (p = 0.0056). The time required to apply ILRFA was 12 minutes. CONCLUSION: Partial splenectomy was achieved in the ovine spleen using radiofrequency energy with minimal blood loss.

Controlled study of inline radiofrequency ablation (ILRFA) assisted transection of ovine liver.

BACKGROUND: Liver resection is now a standard treatment for primary and secondary hepatic tumors around the world. Intra-operative blood loss during liver resection is a major factor associated with morbidity and mortality. We have developed a new instrument using radiofrequency energy (ILRFA), which is intended to achieve coagulative ablation in a plane. This plane can then be cut through with a scalpel, ultrasonic dissector, or diathermy with minimal blood loss. MATERIALS AND METHODS: Five sheep were used in this non-recovery experiment. In these sheep we performed five liver resections with the ILRFA and five similar resections using diathermy and suturing as control. Blood loss was measured by determining the difference in the weights of dry sponges and blood stained sponges after resection. RESULTS: ILRFA was successful in achieving coagulative ablation in all cases to a width of 1 cm. The mean blood loss in ILRFA was 43.2 g (SD36) and 221.8 g (SD147) in the control group. The bleeding was significantly reduced in ILRFA group with a P value of 0.005. CONCLUSIONS: Bleeding remains an important complication of liver resection. To reduce bleeding during liver surgery, different techniques have been used. In this study, we have demonstrated that by using ILRFA we can perform liver resections in sheep with minimal blood loss.