Monopolar Electrosurgery through Single-Port Laparoscopy: A Potential Hidden Hazard for Bowel Burns

Antecubital Burn Resulting From Antenna Coupling: A Case Report

CASE

We present the case of a 54-year-old man who underwent elective hip disarticulation complicated by third-degree burn of the left antecubital fossa requiring skin graft. After careful review, it was determined that "antenna coupling" as a result of electrosurgery was the likely cause. We present an experiment demonstrating this phenomenon.

CONCLUSION

Antenna coupling is a real but rare cause of intraoperative burns not previously described in the orthopaedic literature. Care should be taken to avoid coiling or running bovie or other electrosurgical device cords with other metallic cords or corded devices.

Capacitive coupling leading to electrical skin burn injury during laparoscopic surgery

Purpose

Trocar-site burns occurring during laparoscopic surgery have been reported in various cases, and several efforts to reduce them are underway. This study aimed to analyze the effect of capacitive coupling on trocar site by observing electrical and histological changes for electrical skin burn injury.

Methods

To measure the electrical changes relating to capacitive coupling, the temperature, current, voltage, and impedance around the trocar were measured when an open circuit and a closed circuit were formed using insulation intact instruments and repeated after insulation failure. After the experiment, the tissue around the trocar was collected, and microscopic examination was performed.

Results

When open circuits were formed with the intact insulation, the impedance was significantly reduced compared to the cases of closed circuits (142.0 Ω vs. 109.3 Ω, p = 0.040). When the power was 30 W and there was insulation failure, no significant difference was measured between the open circuit and the closed circuit (147.7 Ω vs. 130.7 Ω, p = 0.103). Collagen hyalinization, nuclear fragmentation, and coagulation necrosis suggesting burns were observed in the skin biopsy at the trocar insertion site.

Conclusion

This study demonstrated that even with a plastic trocar and electrosurgical instruments that have intact insulation, if an open circuit is formed, capacitive coupling increases, and trocar-site burn can occur. When using electrocautery, careful manipulation must be taken to avoid creating an open circuit to prevent capacitive coupling related to electrical skin burn.

The Effect of TISSEELTM on Confined Bowel Perforation: An Experimental Study

OBJECTIVE

During the last decades, surgeons of several specialties presenting different levels of expertise in colon handling have been involved in laparoscopic procedures. The aim of the present experimental study was to investigate the feasibility of TISSEELTM versus the conventional suture placement technique on confined bowel lesions in rats.

METHODS

Twenty-four Sprague-Dawley rats underwent confined bowel perforation and were divided into three groups: the SUTURE group (sutures were used), the SUTURE + TISSEELTM group (sutures and TISSEELTM were utilized), and the TISSEELTM group (only TISSEELTM was used). Blinded histopathologic analysis followed animal sacrifice.

RESULTS

The median weight of the rats was 526 ± 50 g. A single animal had hematochezia on the first postoperative day. Cessation of bleeding at the perforation margin was indicated intraoperatively after TISSEELTM application. Animals in the TISSEELTM group presented less intraperitoneal adhesions and lower hemorrhagic infiltration compared to animals of the two other groups. In addition, animals in the TISSEELTM group showed thrombus formation at the bowel perforation site compared to animals of the two other groups (p = 0.042). Histopathologic analysis demonstrated reduced inflammatory reaction (p = 0.003), diminished fibrosis (p = 0.001), and better tissue regeneration (p = 0.000) in the TISSEELTM group compared to the other two groups.

CONCLUSION

Application of TISSEELTM at the perforation site was associated with increased regeneration of the intestinal wall and less inflammatory and fibrotic reaction compared to suture placement. However, more experimental and clinical studies should be conducted before implementation in humans.

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.

Fibrin sealants as an adequate treatment alternative to traditional suturing for confined bowel lesions: A hypothesis for future experimental research

Bowel perforation is a rare, but serious complication of laparoscopic surgery with a mortality rate that reaches 20%. There are several risk factors that could predispose to bowel perforation, but the surgeon's experience and the difficulty of each case play the most important role. Delayed bowel injuries happen due to conduction of electrical energy through the abdominal cavity, and in the majority of cases require reoperation. Early bowel injuries are caused by thermal injury of an electrosurgical instrument or during the insertion of the laparoscopic instruments inside the peritoneal cavity. Such injuries are recognized during the operation and are usually fixed by placing sutures. TISSEEL™ is a fibrin sealant with various applications in several surgical specialties, that simulates the latter stages of the coagulation cascade, and could be used as an alternative treatment for confined bowel perforations during laparoscopy. The efficacy of fibrin sealants in closing bowel gaps has been tested in some experimental models as well as its adequacy in enhancing bowel anastomoses performed with sutures. In addition, there is scarce evidence that fibrin sealants enhance the healing process after bowel enclosure either combined to suturing or not, which is supported by an experimental pilot study, that was conducted by our study group. The present study tries to combine all the available data in order to propose an effective alternative treatment for confined bowel injuries or controversial cases, that happen during laparoscopic surgery. In that way, every surgeon could face them even without huge expertise, conversions to open surgery would diminish and the disadvantages of suturing would disappear. Future experimental studies should be designed in the terms of extensive comparison of the two methods, with the purpose of this comparison to be tested in humans in the future.

Hand-to-hand coupling and strategies to minimize unintentional energy transfer during laparoscopic surgery

BACKGROUND

Energy-based devices are used in nearly every laparoscopic operation. Radiofrequency energy can transfer to nearby instruments via antenna and capacitive coupling without direct contact. Previous studies have described inadvertent energy transfer through bundled cords and nonelectrically active wires. The purpose of this study was to describe a new mechanism of stray energy transfer from the monopolar instrument through the operating surgeon to the laparoscopic telescope and propose practical measures to decrease the risk of injury.

METHODS

Radiofrequency energy was delivered to a laparoscopic L-hook (monopolar "bovie"), an advanced bipolar device, and an ultrasonic device in a laparoscopic simulator. The tip of a 10-mm telescope was placed adjacent but not touching bovine liver in a standard four-port laparoscopic cholecystectomy setup. Temperature increase was measured as tissue temperature from baseline nearest the tip of the telescope which was never in contact with the energy-based device after a 5-s open-air activation.

RESULTS

The monopolar L-hook increased tissue temperature adjacent to the camera/telescope tip by 47 ± 8°C from baseline (P < 0.001). By having an assistant surgeon hold the camera/telescope (rather than one surgeon holding both the active electrode and the camera/telescope), temperature change was reduced to 26 ± 7°C (P < 0.001). Alternative energy devices significantly reduced temperature change in comparison to the monopolar instrument (47 ± 8°C) for both the advanced bipolar (1.2 ± 0.5°C; P < 0.001) and ultrasonic (0.6 ± 0.3°C; P < 0.001) devices.

CONCLUSIONS

Stray energy transfers from the monopolar "bovie" instrument through the operating surgeon to standard electrically inactive laparoscopic instruments. Hand-to-hand coupling describes a new form of capacitive coupling where the surgeon's body acts as an electrical conductor to transmit energy. Strategies to reduce stray energy transfer include avoiding the same surgeon holding the active electrode and laparoscopic camera or using alternative energy devices.

Single-incision laparoscopic surgery increases the risk of unintentional thermal injury from the monopolar "Bovie" instrument in comparison with traditional laparoscopy

BACKGROUND

Single-incision laparoscopic surgery (SILS) places multiple instruments in close, parallel proximity, an orientation that may have implications in the production of stray current from the monopolar "Bovie" instrument. The purpose of this study was to compare the energy transferred during SILS compared to traditional four-port laparoscopic surgery (TRD).

METHOD

In a laparoscopic simulator, instruments were inserted via SILS or TRD setup. The monopolar generator delivered energy to a laparoscopic L-hook instrument for 5-s activations on 30-Watts coag mode. The primary outcome (stray current) was quantified by measuring the heat of liver tissue held adjacent to the non-electrically active 10-mm telescope tip and Maryland grasper in both the SILS and TRD setups. To control for the potential confounder of stray energy coupling via wires outside the surgical field, the camera cord and active electrode wires were oriented parallel or completely separated.

RESULTS

SILS and TRD setups create similar amounts of stray current as measured by increased tissue temperature at the non-electrically active telescope tip (41 ± 12 vs. 39 ± 10 °C; p = 0.71). Stray current was greater in SILS compared to TRD at the tip of the non-electrically active Maryland forceps (38 ± 9 vs. 20 ± 10 °C; p < 0.01). Separation of the active electrode and camera cords did not change the amount of stray energy in the SILS orientation for either telescope (39 ± 10 °C bundled vs. 36 ± 10 °C separated; p = 0.40) or grasper (38 ± 9 °C bundled vs. 34 ± 11 °C separated; p = 0.19) but did in the TRD orientation (41 ± 12 bundled vs. 24 ± 10 separated; p < 0.01). When SILS was compared to TRD with the cords separated, SILS increased stray energy at both the telescope tip and grasper tip (36 ± 10 vs. 24 ± 10 °C; p < 0.01 and 34 ± 11 vs. 17 ± 8 °C; p < 0.01).

CONCLUSION

SILS increases stray energy transfer nearly twice as much as TRD with the use of the monopolar instrument. Strategies to mitigate the amount of stray energy in the TRD setup such as separation of the active electrode and camera cords are not effective in the SILS setup. These practical findings should enhance surgeons using the SILS approach of increased stray energy that could result in injury.

Quantifying inadvertent thermal bowel injury from the monopolar instrument

BACKGROUND

Insulation defects are observed in 3-39 % of laparoscopic instruments. Electrosurgical injuries due to insulation defects or capacitive coupling remain an issue in laparoscopic surgery with a prevalence of 0.6-5 per thousand cases. Shielded instruments with active electrode monitoring (AEM) have been postulated to prevent these injuries. The benefit of these instruments has not been quantified. Most bowel injuries are unrecognized intra-operatively. Injury is revealed only after the patient exhibits peritonitis symptoms and surgical intervention to repair the bowel is required. These injuries may result in devastating and costly complications or mortality. The extent of bowel injury possible with commonly used generator settings and associated energy output has never been histologically defined. Our objectives in this experimental study were: quantify and compare the energy released through insulation defects or capacitive coupling with standard unshielded monopolar versus shielded instruments with (AEM), determine energy required to cause a visible burn, and relate the histological burn depth to a given amount of energy.

METHODS

Ex vivo porcine jejunum was used for tissue testing. An oscilloscope measured energy output from three common electrosurgical generators at recommended power settings with standard or AEM instruments with insulation defects and in capacitive coupling scenarios. Presence of a visible burn was noted, and depth of tissue damage for a given amount of energy was measured histologically.

RESULTS

All samples that received ≥3.8 J of energy had visible burns. As little as 10 J caused full wall thickness burns. 3.8 J was exceeded at the 30- and 50-W power settings in every experimental scenario using standard monopolar instruments; AEM instruments never approached this much energy.

CONCLUSIONS

Serious burn injury results from small amounts of energy leaked from standard instruments. AEM instruments appeared protective and did not leak sufficient energy to cause burn injuries to the bowel.

Unintended stray energy from monopolar instruments: beware the dispersive electrode cord

BACKGROUND

The monopolar instrument emits stray radiofrequency energy from its cord when activated. This is a source of unintended thermal injury to patients. Stray energy emitted from the dispersive electrode cord has not been studied. The purpose of this study was to determine whether, and to what extent, the dispersive electrode cord contributes to unintentional energy transfer and describe practical steps to minimize risk.

METHODS

In a laparoscopic simulator, a monopolar generator delivered radiofrequency energy to an L-hook. Thermal imaging quantified the change in tissue temperature nearest to the tip of a non-electrical instrument following activation. The orientation of the dispersive electrode cord was varied relative to other instruments.

RESULTS

When the dispersive electrode cord is parallel to the camera cord, tissue temperature increased at the telescope tip by 46 ± 6 °C from baseline (p < 0.001). Similar heat was generated when the camera cord was oriented parallel to the active electrode cord (46 ± 6 vs. 48 ± 7 °C, respectively, p = 0.48). Adding a second dispersive electrode decreased the temperature change (46 ± 6 vs. 25 ± 9 °C, p < 0.001). Temperature increase was greater with coagulation versus cut mode (33 ± 7 vs. 22 ± 6 °C, p < 0.001).

CONCLUSION

Stray energy emitted from the dispersive electrode cord heats tissue >40 °C via antenna coupling; the same magnitude as the active electrode cord. Practical steps to minimize stray energy transfer include avoiding orienting the dispersive electrode cord in parallel with other cords, adding a second dispersive electrode, and using low-voltage cut mode.

Delayed Manifestations of Laparoscopic Bowel Injury

Bowel injury (BI) is a complication of open and laparoscopic abdominal surgery associated with increased morbidity and mortality. If BI is missed at the time it occurs, it can have devastating consequences. Electrosurgery is used extensively in laparoscopic surgery and can cause thermal injuries that are harder to detect than mechanical injuries and may evolve over time. The medical literature of the past 10 years was searched for large series and compilation studies reporting overall incidence of and mortality from BI in laparoscopy, and the results of seven relevant articles, which included over 300,000 procedures, were analyzed and tabulated. The literature was then reviewed for additional information about the specific incidence and outcome of missed BI and the role of electrosurgical thermal sources in causing BI. BI is underreported, frequently missed at surgery, and results in significant morbidity and mortality that can be ground for malpractice claims against the surgeon. Thermal injury from electrosurgical instruments may be involved in a number of injuries in laparoscopic surgery. Nearly undetectable partial-thickness thermal injury may play a role in the atypical and delayed presentation of some cases of BI.

[Complications of minimally invasive pancreas resection for pancreatic neuroendocrine tumors]

BACKGROUND

Laparoscopic pancreas resections are performed with increasing frequency for pancreatic neuroendocrine tumors and other benign and malignant diseases.

OBJECTIVES

This article describes the complications arising from laparoscopic resection of pancreatic neuroendocrine tumors and compares them to complications arising from similar open procedures.

METHODS

Case series, reports, trials and meta-analyses were analyzed and the results are described and discussed.

RESULTS

The types and the frequencies of complications are comparable for laparoscopic and open resection of pancreatic neuroendocrine tumors. The lack of the ability to perform an intraoperative examination of the pancreas to detect the tumors can be alleviated by laparoscopic ultrasound examination or in the case of tumors expressing somatostatin receptors by preoperative DOTATATE positron emission tomography (PET) computed tomography (CT) scanning.

CONCLUSION

The complications arising from the resection of pancreatic neuroendocrine tumors do not justify a recommendation for a laparoscopic or open approach.

Surgical complications specific to monopolar electrosurgical energy: engineering changes that have made electrosurgery safer

Monopolar electrosurgical energy is the most commonly used energy source during laparotomic and laparoscopic surgery. The clinical application of monopolar energy is not without risk. Monopolar electrosurgical energy was introduced into surgical practice at the turn of the 20th century. Alternate site burns during laparotomic application were the most common complication for the first half century (i.e., ground point burns and dispersive electrode burns [1920-1970]). The aims of this article were to discuss historic design flaws associated with the most common alternate site burns, ground point burns, and dispersive electrode burns and the technological advancements introduced to mitigate these risks to the patient and to discuss current design flaws associated with stray energy burns during laparoscopy because of insulation failure and capacitive coupling and the technological advancements introduced to eliminate these risks to the patient. Today, insulation failure and capacitive coupling are the most common reasons for electrosurgical injury during laparocopic procedures. There is a need for advanced technology such as active electrode monitoring to address these invisible risks to the surgeon and their patients. In addition, the laparoscopic surgeon should be encouraged to study the basic biophysics involved in electrosurgery.

Economics and energy sources

Energy-based instrumentation has not only facilitated the rapid adoption of laparoscopic surgery, but could be considered essential for the completion of abdominal and pelvic procedures under endoscopic guidance. For decades, relatively simple and generic reusable monopolar and bipolar systems were the only options available. More recently, the available options for energy-based surgical instrumentation have become more crowded with the introduction of ultrasound-based cutting and sealing instruments and proprietary, impedance monitoring radiofrequency coagulation devices. Such instrumentation is presented as being easier to use as well as providing greater safety and efficacy. However, these new instruments typically require the expenditure of capital for proprietary energy generators and are usually designed to be for single use, a circumstance that increases per case costs, a circumstance that begs the question of value. Do the additional costs expended for the more expensive devices translate into reduced complications, faster operating time, or even wider access to minimally invasive procedures because they enable more surgeons to offer the service? Herein is explored the complex economic issues associated with the use of energy-based surgical devices as they apply to minimal access surgery in general and to laparoscopic procedures specifically.

Energetic soft-tissue treatment technologies: an overview of procedural fundamentals and safety factors

BACKGROUND

Energy administered during soft-tissue treatments may cauterize, coagulate, seal, or otherwise affect underlying structures. A general overview of the functionality, procedural outcomes, and associated risks of these treatments, however, is not yet generally available. In addition, literature is sometimes inconsistent with regards to terminology. Along with the rapid expansion of available energetic instruments, particularly in the field of endoscopic surgery, these factors may complicate the ability to step back, review available treatment options, and identify critical parameters for appropriate use.

METHODS

Online databases of PubMed, Web of Science, and Google Scholar were used to collect literature on popular energetic treatments, such as electrosurgery, plasma surgery, ultrasonic surgery, and laser surgery. The main results include review and comparison studies on the working mechanisms, pathological outcomes, and procedural hazards.

RESULTS

The tissue response to energetic treatments can be largely explained by known mechanical and thermal interactions. Application parameters, such as the interaction time and power density, were found to be of major influence. By breaking down treatments to this interaction level, it is possible to differentiate the available options and reveal their strengths and weaknesses. Exact measures of damage and alike quantifications of interaction are, although valuable to the surgeon, often either simply unknown due to the high impact of tissue and application-dependent parameters or badly documented in previous studies. In addition, inconsistencies in literature regarding the terminology of used techniques were observed and discussed. They may complicate the formulation of cause and effect relations and lead to misconceptions regarding the treatment performance.

CONCLUSIONS

Some basic knowledge on used energetic treatments and settings and a proper use of terminology may enhance the practitioner's insight in allowable actions to take, improve the interpretation and diagnosis of histological and mechanical tissue changes, and decrease the probability of iatrogenic mishaps.

Radiofrequency energy antenna coupling to common laparoscopic instruments: practical implications

BACKGROUND

Electromagnetic coupling can occur between the monopolar "Bovie" instrument and other laparoscopic instruments without direct contact by a phenomenon termed antenna coupling. The purpose of this study was to determine if, and to what extent, radiofrequency energy couples to other common laparoscopic instruments and to describe practical steps that can minimize the magnitude of antenna coupling.

METHODS

In a laparoscopic simulator, monopolar radiofrequency energy was delivered to an L-hook. The tips of standard, nonelectrical laparoscopic instruments (either an unlit 10 mm telescope or a 5 mm grasper) were placed adjacent to bovine liver tissue and were never in contact with the active electrode. Thermal imaging quantified the change in tissue temperature nearest the tip of the telescope or grasper at the end of a 5 s activation of the active electrode.

RESULTS

A 5 s activation (30 watts, coagulation mode, 4 cm separation between instruments) increased tissue temperature compared with baseline adjacent to the grasper tip (2.2 ± 2.2 °C; p = 0.013) and telescope tip (38.2 ± 8.0 °C; p < 0.001). The laparoscopic telescope tip increased tissue temperature more than the laparoscopic grasper tip (p < 0.001). Lowering the generator power from 30 to 15 Watts decreased the heat generated at the telescope tip (38.2 ± 8.0 vs. 13.5 ± 7.5 °C; p < 0.001). Complete separation of the camera/light cords and the active electrode cord decreased the heat generated near the telescope tip compared with parallel bundling of the cords (38.2 ± 8.0 vs. 15.7 ± 11.6 °C; p < 0.001).

CONCLUSIONS

Commonly used laparoscopic instruments couple monopolar radiofrequency energy without direct contact with the active electrode, a phenomenon that results in heat transfer from a nonelectrically active instrument tip to adjacent tissue. Practical steps to minimize heat transfer resulting from antenna coupling include reducing the monopolar generator power setting and avoiding of parallel bundling of the telescope and active electrode cords.