Monopolar Electrosurgical Device Research Articles

Clinical Issues-August 2022.

Use of sterile vests Key words: sterile technique, surgical attire, gown, contaminated, back. Bare arms for unscrubbed personnel Key words: long sleeves, cover jacket, disposable jacket, patient skin antisepsis, surgical site infection (SSI). Preventing thermal injury from electrosurgical devices Key words: electrosurgical unit (ESU), monopolar electrosurgical device, electrode, alternate site thermal injury, burn. Preoperative site marking for minimally invasive procedures Key words: surgical site, wrong-site surgery, alternative site marking, point of access, preprocedure verification.

New Kid on the Block: “Speedboat”

AbstractInnovations in devices and techniques have parallelly propelled the field of therapeutic endoscopy in gastrointestinal tract. With the development of endoscopic resection techniques and the availability of newly designed electrosurgical knives, the minimally invasive management of early gastrointestinal neoplasms has revolutionized. The currently available electrosurgical knives are monopolar devices, not equipped with injection needle and required to be exchanged with coagulation forceps for hemostasis. Monopolar electrosurgical devices require higher voltages with associated risks. A recent innovation in the field of endoscopic knives is a new device called “Speedboat” device, specially designed for use in endoscopic dissection procedures. This is a bipolar device that utilizes radio frequency energy for cutting and microwave energy for achieving hemostasis. Speedboat device possesses hemostasis capability and has an integrated injection needle that imparts an “all-in-one” quality to this device. Preliminary data suggest the safety and utility of this device in performing a variety of endoscopic dissection and resection procedures including endoscopic submucosal dissection, per-oral endoscopic myotomy, and resection of subepithelial tumors.

Quantifying the magnitude of local tendon injury from electrosurgical transection.

Electrocautery is a common surgical technique and is often used during shoulder arthroplasty to elevate or transect the subscapularis tendon. The relative amount of tissue damage caused by cautery as opposed to sharp transection is not currently known. The purpose of this study was to examine local tissue damage resulting from electrocautery vs. sharp transection with a scalpel. We hypothesized that the electrosurgical unit would cause higher collateral tissue damage and cell death compared with sharp transection. Twelve cadaveric ovine shoulders were randomized to either the electrosurgical or sharp transection group. The infraspinatus tendon was isolated, and a partial-thickness transection was made using either a monopolar electrosurgical device (Bovie) or No. 10 scalpel blade. Tendon explants were then visualized with confocal microscopy to evaluate tissue architecture. A live/dead assay was performed using microscopy imaging analysis software. Comparisons between Bovie and scalpel transection were made using the Mann-Whitney U test, and the cell death percentage at standardized distances from the transection site was compared between groups using a mixed-model analysis. Significance was defined at P < .05. The cellular and tendon fibril architecture was well maintained beyond the scalpel transection site, whereas Bovie transection disrupted the architecture beyond its transection path. The percentage of dead cells in the Bovie group (74.9% ± 31.2%) was significantly higher than that in the scalpel group (27.6% ± 29.9%, P = .0004). Compared with the transection site, the cell death percentage after Bovie transection significantly declined at 2.5 mm whereas that after scalpel transection significantly declined at 1 mm from the transection site. There was a significantly higher dead cell percentage in the Bovie transection group, indicating extensive damage beyond the local incision site, compared with sharp transection. Electrosurgical transection of the ovine infraspinatus tendon exvivo caused higher cell death and greater tissue architecture disruption compared with sharp scalpel transection.

Ultrasonic dissection versus electrocautery for immediate prosthetic breast reconstruction.

BackgroundUltrasonic dissection devices cause less thermal damage to the surrounding tissue than monopolar electrosurgical devices. We compared the effects of using an ultrasonic dissection device or an electrocautery device during prosthetic breast reconstruction on seroma development and short-term postoperative complications.MethodsWe retrospectively reviewed the medical records of patients who underwent implant-based reconstruction following mastectomy between March 2017 and September 2018. Mastectomy was performed by general surgeons and reconstruction by plastic surgeons. From March 2017 to January 2018, a monopolar electrosurgical device was used, and an ultrasonic dissection device was used thereafter. The other surgical methods were the same in both groups.ResultsThe incidence of seroma was lower in the ultrasonic dissection device group than in the electrocautery group (11 [17.2%] vs. 18 [31.0%]; P=0.090). The duration of surgery, total drainage volume, duration of drainage, overall complication rate, surgical site infection rate, and flap necrosis rate were comparable between the groups. Multivariate analysis revealed that the risk of seroma development was significantly lower in the ultrasonic dissection device group than in the electrocautery group (odds ratio for electrocautery, 3.252; 95% confidence interval, 1.242–8.516; P=0.016).ConclusionsThe findings of this study suggest that the incidence of seroma can be reduced slightly by using an ultrasonic dissection device for prosthesis-based breast reconstruction. However, further randomized controlled studies are required to verify our results and to assess the cost-effectiveness of this technique.

Fire Safety in Mohs Micrographic Surgery.

Surgical fire is a rare event, but one with potentially devastating patient outcomes. This study was conducted to investigate the incidence, risk factors, and outcome of surgical fires experienced by members of the American College of Mohs Surgeons (ACMS). An internet survey was developed and sent to ACMS members. Data collected included total years of experience, total number of cases, typical management of supplemental oxygen, and surgical fires experienced. Eighty participants contributed data on 886,200 cases of MMS. Nine surgeons (11%) reported at least 1 surgical fire, yielding an estimated incidence of 1 fire per 88,620 cases (0.001%). The most common site of involvement was the scalp (67%). Common ignition sources included monopolar electrosurgical devices (78%) and battery-powered thermal cautery (22%). Fuel sources included towels or drapes, gauze, isopropyl alcohol, aluminum chloride, hairspray, and diethyl ether. Supplemental oxygen was not involved in any of the cases. Five patients suffered singed hair while 4 patients did not suffer any injuries. None suffered any permanent functional or aesthetic deformities. The overall risk of surgical fire in MMS is minimal. However, safety measures and greater awareness of fire risks are necessary to prevent patient harm.

Skeletonized internal thoracic artery harvesting: a low thermal damage electrosurgical device provides improved endothelial layer and tendency to better integrity of the vessel wall compared to conventional electrosurgery

BackgroundElectrosurgery is fundamental to the precise, fast and bloodless preparation of internal thoracic artery grafts in cardiac surgery. The PEAK PlasmaBlade is a monopolar electrosurgical device that uses pulsed radiofrequency energy to generate a plasma-mediated discharge along an insulated electrode, creating a cutting edge while the blade stays near body temperature. The aim of this study is to compare the histological samples, cardiac computed-tomography of graft patency, and clinical outcomes of patients after off-pump coronary artery bypass grafting with preparation of the internal thoracic arteries by a conventional electrosurgical device and the PlasmaBlade.MethodsIn twenty subjects one internal thoracic artery was prepared with PlasmaBlade and the other artery with a conventional electrosurgical device. Histological samples were evaluated for three factors for potential graft failure: endothelial damage, integrity of the vessel wall and adventitial hemorrhage. Five samples per artery were evaluated by a novel scoring method based on the exposed circumference of the histological sample (“0”: 0%, “1”: 1–25%, “2”: 26–50%, “3”: 51–75%, “4”: ≥76% of the circumference). The Wilcoxon signed ranks test for mean scores within subjects was performed. Six-month-follow up by cardiac computed tomography for evaluation of graft patency was completed in 16 patients.ResultsHistological results demonstrated significantly less endothelial damage after PlasmaBlade (83% vs 60%, absolute: 75/90 vs. 53/89 samples with score “0–1”, p = 0.04). PlasmaBlade samples demonstrated a tendency to better wall integrity (72% vs. 54%, absolute: 64/89 vs. 47/87 samples with score “0–1”, p = 0.32). There were no differences in endothelial bleeding (PlasmaBlade 46% vs. electrosurgery 53%, absolute: 41/88 vs. 48/90 samples with score “0–1”, p = 0.63). Computed tomography confirmed non-inferiority of the PlasmaBlade to conventional electrosurgery with a patency rate of 94%.ConclusionHistologically, internal thoracic arteries harvested with PlasmaBlade demonstrate a more intact endothelial layer and a tendency to better wall integrity. Computed tomography of graft patency speaks for non-inferiority to conventional electrosurgery. PlasmaBlade may be preferable to conventional electrosurgery, if further follow-up confirms patency of internal thoracic arteries.Trial registrationNCT03510026, registered 4th April 2018 (retrospectively registered).

Transpapillary endopancreatic surgery: decompression of duct system and comparison of greenlight laser with monopolar electrosurgical device in ex vivo and in vivo animal models.

Endopancreatic surgery (EPS) is an experimental minimally invasive technique for resection of pancreatic tissue from inside the pancreatic duct, accessed via the duodenum and papilla. It is proposed as an alternative to duodenum-preserving pancreatic head resection in benign diseases such as chronic pancreatitis (CP). This study evaluated the use of EPS for resection of pancreatic duct stenoses. Moreover, greenlight laser (GLL) and monopolar electrosurgical device (MES) were compared as resection tools for EPS. The suitability of EPS for resection of stenoses was evaluated in ex vivo bovine pancreas (n = 8). Artificially created stenoses in the pancreatic head were accessed via the duodenal papilla and resected from inside the organ with MES through a rigid endoscope. Furthermore, standardized pancreatic resections were performed in an in vivo porcine model using either GLL (n = 18) or MES (n = 18) to compare blood loss, operating time, and complications. Thermal damage to the surrounding tissue was assessed using a standardized histological classification. Stenosis resection by EPS was feasible in 8/8 bovine pancreases, with a procedure time of 17 (12-24) min. No perforation of the organ occurred. Resection by GLL was associated with reduced blood loss [median 1.7 (interquartile range 0.6-2.6) ml vs. 5.1 (3.8-13.2) ml; p < 0.01] and shorter operating time [109 (81-127) s vs. 390 (337-555) s; p < 0.01] compared with MES. The zone of thermal tissue damage was more extensive when using GLL than with MES [4.12 (3.48-4.89) mm vs. 1.33 (1.09-1.48) mm; p < 0.01]. Transduodenal-transpapillary EPS can be used to resect stenoses and decompress the pancreatic duct system. Both GLL and MES are feasible resection methods for EPS. However, GLL showed better hemostatic characteristics than MES in an in vivo porcine model. Safety measures such as temperature control and image-guided navigation should be employed to monitor the resection and tissue heating.

Micro/nanostructured surface modification using femtosecond laser pulses on minimally invasive electrosurgical devices.

The purpose of the present study was to examine thermal damage and a sticking problem in the tissue after the use of a minimally invasive electrosurgical device with a nanostructured surface treatment that uses a femtosecond laser pulse (FLP) technique. To safely use an electrosurgical device in clinical surgery, it is important to decrease thermal damage to surrounding tissues. The surface characteristics and morphology of the FLP layer were evaluated using optical microscopy, scanning electron microscopy, and transmission electron microscopy; element analysis was performed using energy-dispersive X-ray spectroscopy, grazing incidence X-ray diffraction, and X-ray photoelectron spectroscopy. In the animal model, monopolar electrosurgical devices were used to create lesions in the legs of 30 adult rats. Animals were sacrificed for investigations at 0, 3, 7, 14, and 28days postoperatively. Results indicated that the thermal damage and sticking situations were reduced significantly when a minimally invasive electrosurgical instrument with an FLP layer was used. Temperatures decreased while film thickness increased. Thermographic data revealed that surgical temperatures in an animal model were significantly lower in the FLP electrosurgical device compared with that in the untreated one. Furthermore, the FLP device created a relatively small area of thermal damage. As already mentioned, the biomedical nanostructured layer reduced thermal damage and promoted the antisticking property with the use of a minimally invasive electrosurgical device. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 865-873, 2017.

Laparoscopic Submucosal Dissection for Gastrointestinal Stromal Tumor of the Stomach: A Novel Technique for Local Excision with a Minimal Curative Margin

Background: Laparoscopic wedge resection is accepted as a curative treatment for small- and mediumsized gastroin-testinal stromal tumors (GISTs) of the stomach. Conventional methods involving surgical staplers require relatively large lateral margins, which may cause deformity and postoperative dysfunction of the gastric remnant. In this study, we introduce a novel technique called laparoscopic submucosal dissection (LSD) in which the defects of the stomach are minimized and a microscopic negative margin is secured. Methods: The normal seromuscular layer of the gastric wall was dissected with a 5 mm lateral margin. Then, the submucosal tissue was divided carefully using a monopolar electrosurgical device with a curved spatula tip. Results: The operation time was 170 min, and the amount of bleeding was very small. We confirmed an intact pseudo-capsule and marginal subserosal or submucosal tissue of the tumor by histological analysis. The postoperative course was uneventful with no complications. Endoscopy showed minimal deformity of the gastric remnant. Conclusions: We think that LSD is a curative and less invasive treatment for GIST of the stomach. Further investigations are necessary to evaluate the oncological and functional outcomes of this procedure.

Monopolar Electrosurgical Thermal Management for Minimizing Tissue Damage

In this study, a novel thermal management system (TMS) is developed for the minimization of thermal spread created by a monopolar electrosurgical device, the most commonly used surgical instrument. The phenomenon of resistive heating of tissue is modeled using the finite-element method (FEM) to analyze the electrical potential and temperature distributions in biological tissue subjected to heat generation during monopolar electrosurgery. Ex vivo experiments are used to validate the FEM by comparing the model predicted and experimentally measured temperatures. The predicted FEM maximum temperature 1.0 m adjacent to the electrode is within 1% of the experimentally measured maximum temperature using a standard monopolar pencil electrode. A TMS consisting of adjacent cooling channels produces coagulation volumes 80% that of standard monopolar procedures while maintaining comparable temperatures in the targeted tissue below the electrode. In vivo temperatures using a device incorporating a TMS at distances of 2 and 3 m adjacent to the electrode edge are maintained below temperatures known to damage tissue.

Monopolar Electrosurgical Thermal Management System to Reduce Lateral Thermal Damage During Surgery

A monopolar electrosurgical device is the most commonly used energy-based surgical instrument. Monopolar devices are primarily applied to incise, ablate, dissect, and coagulate tissue by transferring electrical energy to the tissue in the form of heat generation through resistive heating. The substantial amount of heat created by the monopolar device has been shown to spread throughout the tissue, creating unintended tissue damage, which can lead to nerve thermal damage and loss of normal bodily functions. Due to this fact, energy-based devices have had a limited use in surgical procedures performed near neurovascular bundles. The extent to which the generated heat raises the temperature of the surrounding tissue is referred to as the device’s thermal spread. In this study, ex vivo and in vivo experiments have shown that a novel thermal management system (TMS) can reduce the amount of thermal spread created by a typical monopolar device, thus eliminating the thermal collateral tissue damage typically caused during a monopolar procedure. The incorporation of a TMS consisting of adjacent cooling channels reduces the thermal spread of the device, as illustrated in a reduction as high as 50% in the maximum temperature recorded during an in vivo experimental procedure. The design of the TMS was aided by finite element modeling (FEM). The phenomenon of monopolar resistive heating was modeled to analyze the temperature distributions in biological tissue subjected to heat generation by a commonly used monopolar electrosurgical device. The mathematical model was verified by comparing the model’s predicted temperature distribution with experimental results. Ex vivo experiments were performed with liver tissue heated by a monopolar pencil electrode. The experimental data for 1 mm distance from the electrode are seen to fit within 1% of the predicted temperature values by the FEM simulation.

Fire/burn risk with electrosurgical devices and endoscopy fiberoptic cables

Purpose The purpose of the study was to systematically explore the fire and burn risk associated with fiberoptic cables and electrosurgical devices. Materials and methods A 300-W light source was connected to a standard gray fiberoptic light cable. The end of the cable was either rested atop or buried within a cotton towel or polypropylene drape in the presence or absence of 100% oxygen for up to 10 minutes. A monopolar electrosurgical device set at 1 W, 10 W, or 30 W was tested on a cotton towel or polypropylene drape for a period of 30 seconds. All trials were repeated. Results Resting the light cable on top of the cotton towel or polypropylene drape with or without oxygen produced no result. Burying the end of the cable within the drape produced a hole in the drape within 15 seconds both with and without oxygen. Burying the end of the cable within the cotton towel produced a yellow discoloration after 2 minutes both with and without oxygen. The monopolar electrosurgical device set at 30 W burned immediately through the polypropylene drape, producing a skin burn. All other trials with monopolar electrocautery produced no result. No flame or fire was produced in any trial. Conclusions Fiberoptic cables and electrosurgical generators represent a serious burn risk for surgical patients, with operating room drapes and towels affording only limited protection. Otolaryngologists should be keenly aware of the risks that these devices represent because our specialty uses them frequently.

Evaluation of stray radiofrequency radiation emitted by electrosurgical devices

Electrosurgery refers to the passage of a high-frequency, high-voltage electrical current through the body to achieve the desired surgical effects. At the same time, these procedures are accompanied by a general increase of the electromagnetic field in an operating room that may expose both patients and personnel to relatively high levels of radiofrequency radiation. In the first part of this study, we have taken into account the radiation emitted by different monopolar electrosurgical devices, evaluating the electromagnetic field strength delivered by an electrosurgical handle and straying from units and other electrosurgical accessories. As a summary, in the worst case a surgeon's hands are exposed to a continuous and pulsed RF wave whose magnetic field strength is 0.75 A m−1 (E-field 400 V m−1). Occasionally stray radiation may exceed ICNIRP's occupational exposure guidelines, especially close to the patient return plate. In the second part of this paper, we have analysed areas of particular concern to prevent electromagnetic interference with some life-support devices (ventilators and electrocardiographic devices), which have failed to operate correctly. Most clinically relevant interference occurred when an electrosurgery device was used within 0.3 m of medical equipment. In the appendix, we suggest some practical recommendations intended to minimize the potential for electromagnetic hazards due to therapeutic application of RF energy.

Laparoscopic Ureterocalicostomy: Development of a Technique Simplified by Application of Nitinol Clips and a Wet Monopolar Electrosurgery Device

We developed a technique for laparoscopic ureterocalicostomy with the use of intracorporeal suturing and subsequently simplified the technique by application of experimental Nitinol clips. We performed laparoscopic ureterocalicostomy on 16 domestic swine divided into four groups of four animals each. The kidney was exposed laparoscopically, and the renal artery was atraumatically clamped. The lower pole of the kidney was amputated to expose a lower-pole calix, and hemostasis of the cut renal surface was obtained with a wet monopolar electrosurgical device (Floating Ball device [FB]; TissueLink, Dover, NH). Anastomosis of the ureter to the lower-pole calix was performed over a guidewire using 3-0 Vicryl suture in group 1 and Nitinol clips in group 3. A double-J ureteral stent was then deployed retrograde under fluoroscopic guidance. In addition, we evaluated the use of fibrin glue as a sealant over the sutured or clipped anastomotic site (groups 2 and 4, respectively). Ureteral stents were removed after 3 weeks, and the animals were evaluated and sacrificed after an additional 3 weeks. Laparoscopic ureterocalicostomy was completed in all 16 animals. In each case, excellent renal parenchymal hemostasis was obtained with the FB device, with a mean hemostasis time of 4.1 minutes. The mean anastomotic time with standard suture reconstruction was 37.1 +/- 5.4 minutes, while the anastomotic time with the Nitinol clips was 29.0 +/- 8.0 minutes (P = 0.0339). Retrograde pyelograms in groups 1 and 3 (no fibrin glue) showed a patent anastomosis with no hydronephrosis in three of the four animals in each group. One animal in group 1 and one animal in group 3 developed large urinomas secondary to anastomotic failure. The animals that received fibrin glue over the anastomotic site (groups 2 and 4) all showed narrowed anastomoses with severe hydronephrosis. With available instrumentation, laparoscopic ureterocalicostomy is technically feasible. Nitinol clip technology significantly reduces collecting-system reconstruction time. Application of fibrin glue as a urinary tract sealant resulted in an unexpected adverse outcome.

Spark erosion myectomy in hypertrophic obstructive cardiomyopathy

The design features of the cutting electrode and the electrical characteristics of a monopolar electrosurgical device were specially adapted for performing a septal myectomy in patients with hypertrophic obstructive cardiomyopathy. Both the cutting behavior and electrode design were found to facilitate myectomy.