Stray energy transfer during endoscopy

Stray energy injury during robotic versus laparoscopic inguinal hernia repair: a randomized controlled trial

BACKGROUND

Stray energy transfer from monopolar instruments during laparoscopic surgery is a recognized cause of potentially catastrophic complications. There are limited data on stray energy injuries in robotic surgery. We sought to characterize stray energy injury in the form of superficial burns to the skin surrounding laparoscopic and robotic trocar sites. Our hypothesis was that stray energy burns will occur at all laparoscopic and robotic port sites.

METHODS

We conducted a prospective, randomized controlled trial of patients undergoing elective unilateral inguinal hernia repair at a VAMC over a 4-year period. Surgery was performed via transabdominal preperitoneal approach either laparoscopic-assisted (TAPP) or robotic-assisted (rTAPP). A monopolar scissor was used to deliver energy at 30W coagulation for all cases. At completion of the procedure, skin biopsies were taken from all the port sites. A picro-Sirius red stain was utilized to identify thermal injury by a blinded pathologist.

RESULTS

Over half (54%, 59/108) of all samples demonstrated thermal injury to the skin. In the laparoscopic group, 49% (25/51) samples showed thermal injury vs. 60% (34/57) in the robotic group (p = 0.548). The camera port was the most frequently involved with 68% (13/19) rTAPP samples showing injury vs. 47% (8/17) in the TAPP group (p = 0.503). There was no difference in the rate of injury at the working port site (rTAPP 53%, 10/19 vs. TAPP 47%, 8/17; p = 0.991) or the assistant port site (rTAPP 58%, 11/19 vs. TAPP 53%, 9/17; p = 0.873).

CONCLUSIONS

Stray energy causes thermal injury to the skin at port sites in the majority robotic laparoscopic TAPP inguinal hernia repairs. There is no difference in stray energy transfer between the laparoscopic and robotic platform. This is the first study to confirm in-vivo transfer of stray energy during robotic surgical procedures. More study is needed to determine the clinical significance of these thermal injuries.

Robotic stray energy with constant-voltage versus constant-power regulating electrosurgical generators

INTRODUCTION

Stray energy from surgical energy instruments can cause unintended thermal injuries. There are no published data regarding electrosurgical generators and their influence on stray energy transfer during robotic surgery. There are two approved generators for the DaVinci Xi robotic platform: a constant-voltage regulating generator (cVRG) and a constant-power regulating generator (cPRG). The purpose of this study was to quantify and compare stray energy transfer in the robotic Xi platform using a cVRG versus a cPRG.

METHODS

An ex vivo bovine model was used to simulate a standard multiport robotic surgery. The DaVinci Xi (Intuitive Surgical, Sunnyvale, CA) robotic platform was attached to a trainer box using robotic ports. A 5 s, open-air activation of the monopolar scissors was done with commonly used electrosurgical settings using a cPRG (ForceTriad, Covidien-Medtronic, Boulder, CO) or cVRG (ERBE VIO 300 dV 2.0, ERBE USA, Marietta, GA). Stray energy transfer was quantified as the change in tissue temperature (°C) nearest the tip of the assistance grasper (which was not in direct contact with the active monopolar scissors).

RESULTS

Stray energy transfer occurred with both generators. Utilizing common, comparable settings for standard coagulation, significantly less stray energy was transferred with the cVRG versus cPRG (4.4 ± 1.6 °C vs. 41.1 ± 13.0 °C, p < 0.001). Similarly, less stray energy was transferred using cut modes with the cVRG compared to the cPRG (5.61 ± 1.79 °C vs. 33.9 ± 18.4 °C, p < 0.001).

CONCLUSION

Stray energy transfer increases tissue temperatures more than 45C in the DaVinci Xi robotic platform. Low voltage modalities, such as cut or blend; as well as a cVRG generator, significantly reduces stray energy. Robotic surgeons can minimize the risk of stray energy injuries by using these low risk modes and/or generator.

Stray energy transfer in single-incision robotic surgery

INTRODUCTION

Stray energy transfer from surgical monopolar radiofrequency energy instruments can cause unintended thermal injuries during laparoscopic surgery. Single-incision laparoscopic surgery transfers more stray energy than traditional laparoscopic surgery. There is paucity of published data concerning stray energy during single-incision robotic surgery. The purpose of this study was to quantify stray energy transfer during traditional, multiport robotic surgery (TRS) compared to single-incision robotic surgery (SIRS).

METHODS

An in vivo porcine model was used to simulate a multiport or single-incision robotic cholecystectomy (DaVinci Si, Intuitive Surgical, Sunnyvale, CA). A 5 s, open air activation of the monopolar scissors was done on 30 W and 60 W coag mode (ForceTriad, Covidien-Medtronic, Boulder, CO) and Swift Coag effect 3, max power 180 W (VIO 300D, ERBE USA, Marietta, GA). Temperature of the tissue (°C) adjacent to the tip of the assistant grasper or the camera was measured with a thermal camera (E95, FLIR Systems, Wilsonville, OR) to quantify stray energy transfer.

RESULTS

Stray energy transfer was greater in the SIRS setup compared to TRS setup at the assistant grasper (11.6 ± 3.3 °C vs. 8.4 ± 1.6 °C, p = 0.013). Reducing power from 60 to 30 W significantly reduced stray energy transfer in SIRS (15.3 ± 3.4 °C vs. 11.6 ± 3.3 °C, p = 0.023), but not significantly for TRS (9.4 ± 2.5 °C vs. 8.4 ± 1.6 °C, p = 0.278). The use of a constant voltage regulating generator also minimized stray energy transfer for both SIRS (0.7 ± 0.4 °C, p < 0.001) and TRS (0.7 ± 0.4 °C, p < 0.001).

CONCLUSIONS

More stray energy transfer occurs during single-incision robotic surgery than multiport robotic surgery. Utilizing a constant voltage regulating generator minimized stray energy transfer for both setups. These data can be used to guide robotic surgeons in their use of safe, surgical energy.

Monopolar stray energy in robotic surgery

INTRODUCTION

Stray energy transfer from monopolar radiofrequency energy during laparoscopy can be potentially catastrophic. Robotic surgery is increasing in popularity; however, the risk of stray energy transfer during robotic surgery is unknown. The purpose of this study was to (1) quantify stray energy transfer using robotic instrumentation, (2) determine strategies to minimize the transfer of energy, and (3) compare robotic stray energy transfer to laparoscopy.

METHODS

In a laparoscopic trainer, a monopolar instrument (L-hook) was activated with DaVinci Si (Intuitive, Sunnyvale, CA) robotic instruments. A camera and assistant grasper were inserted to mimic a minimally invasive cholecystectomy. During activation of the L-hook, the non-electric tips of the camera and grasper were placed adjacent to simulated tissue (saline-soaked sponge). The primary outcome was change in temperature from baseline (°C) measured nearest the tip of the non-electric instrument.

RESULTS

Simulated tissue nearest the robotic grasper increased an average of 18.3 ± 5.8 °C; p < 0.001 from baseline. Tissue nearest the robotic camera tip increased (9.0 ± 2.1 °C; p < 0.001). Decreasing the power from 30 to 15 W (18.3 ± 5.8 vs. 2.6 ± 2.7 °C, p < 0.001) or using low-voltage cut mode (18.3 ± 5.8 vs. 3.1 ± 2.1 °C, p < 0.001) reduced stray energy transfer to the robotic grasper. Desiccating tissue, in contrast to open air activation, also significantly reduced stray energy transfer for the grasper (18.3 ± 5.8 vs. 0.15 ± 0.21 °C, p < 0.001) and camera (9.0 ± 2.1 vs. 0.24 ± 0.34 °C, p < 0.001).

CONCLUSIONS

Stray energy transfer occurs during robotic surgery. The assistant grasper carries the highest risk for thermal injury. Similar to laparoscopy, stray energy transfer can be reduced by lowering the power setting, utilizing a low-voltage cut mode instead of coagulation mode and avoiding open air activation. These practical findings can aid surgeons performing robotic surgery to reduce injuries from stray energy.

Hepatic Ablation Promotes Colon Cancer Metastases in an Immunocompetent Murine Model

OBJECTIVE

To determine the impact of radiofrequency (RF) and microwave (MW) energy compared to direct cautery on metatstatic colon cancer growth.

BACKGROUND

Hepatic ablation with MW and RF energy creates a temperature gradient around a target site with temperatures known to create tissue injury and cell death. In contrast, direct heat application (cautery) vaporizes tissue with a higher site temperature but reduced heat gradient on surrounding tissue. We hypothesize that different energy devices create variable zones of sublethal injury that may promote tumor recurrence. To test this hypothesis we applied MW, RF, and cautery to normal murine liver with a concomitant metastatic colon cancer challenge.

METHODS

C57/Bl6 mice received hepatic thermal injury with MW, RF, or cautery to create a superficial 3-mm lesion immediately after intrasplenic injection of 50K MC38 colon cancer cells. Thermal imaging recorded tissue temperature during ablation and for 10 seconds after energy cessation. Hepatic tumor location and volume was determined at day 7.

RESULTS

Cautery demonstrated the highest maximum tissue temperatures (129°C) with more rapid return to baseline compared to MW or RF energy. All mice had metastasis at the ablation site. Mean tumor volume was significantly greater in the MW (95.3 mm; P = 0.007) and RF (55.7 mm; P = 0.015) than cautery (7.13 mm). There was no difference in volume between MW and RF energy (P = 0.2).

CONCLUSIONS

Hepatic thermal ablation promotes colon cancer metastasis at the injury site. MV and RF energy result in greater metastatic volume than cautery. These data suggest that the method of energy delivery promotes local metastasis.

The SAGES Fundamental Use of Surgical Energy program (FUSE): history, development, and purpose

BACKGROUND

Adverse events due to energy device use in surgical operating rooms are a daily occurrence. These occur at a rate of approximately 1-2 per 1000 operations. Hundreds of operating room fires occur each year in the United States, some causing severe injury and even mortality. The Society of American Gastrointestinal and Endoscopic Surgeons (SAGES) therefore created the first comprehensive educational curriculum on the safe use of surgical energy devices, called Fundamental Use of Surgical Energy (FUSE). This paper describes the history, development, and purpose of this important training program for all members of the operating room team.

METHODS

The databases of SAGES and the FUSE committee as well as personal photographs and documents of members of the FUSE task force were used to establish a brief history of the FUSE program from its inception to its current status.

RESULTS

The authors were able to detail all aspects of the history, development, and national as well as global implementation of the third SAGES Fundamentals Program FUSE.

CONCLUSIONS

The written documentation of the making of FUSE is an important contribution to the history and mission of SAGES and allows the reader to understand the idea, concept, realization, and implementation of the only free online educational tool for physicians on energy devices available today. FUSE is the culmination of the SAGES efforts to recognize gaps in patient safety and develop state-of-the-art educational programs to address those gaps. It is the goal of the FUSE task force to ensure that general FUSE implementation becomes multinational, involving as many countries as possible.