High Frequency Electric Welding Research Articles

Assessing the influence of parameters on tissue welding in small bowel end-to-end anastomosis in vitro and in vivo.

The use of high-frequency electric welding technology for intestinal end-to-end anastomosis holds significant promise. Past studies have focused on in vitro, and the safety and efficacy of this technology is uncertain, severely limiting the clinical application of this technology. This study investigates the impact of compression pressure, energy dosage, and duration on anastomotic quality using a homemade anastomosis device in both in vitro and in vivo settings. Two hundred eighty intestines and 5 experimental pigs were used for in vitro and in vivo experiments, respectively. The in vitro experiments were conducted to study the effects of initial pressure (50-400kpa), voltage (40-60V), and time (10-20s) on burst pressure, breaking strength, thermal damage, and histopathological microstructure of the anastomosis. Optimal parameters were then inlaid into a homemade anastomosis and used for in vivo experiments to study the postoperative porcine survival rate and the pathological structure of the tissues at the anastomosis and the characteristics of the collagen fibers. The anastomotic strength was highest when the compression pressure was 250kPa, the voltage was 60V, and the time was 15s. The degree of thermal damage to the surrounding tissues was the lowest. The experimental pigs had no adverse reactions after the operation, and the survival rate was 100%. 30days after the operation, the surgical site healed well, and the tissues at the anastomosis changed from immediate adhesions to permanent connections. High-frequency electric welding technology has a certain degree of safety and effectiveness. It has the potential to replace the stapler anastomosis in future and become the next generation of new anastomosis device.

The Results of Using the Method of Bipolar High-frequency Electric Welding to Close Defects of the Dura Mater in Frontal Sinus Tumors with Intracranial Spread, and its Comparison with the Standard Method

The frequency of cerebrospinal fluid leak (CSFL) in the postoperative period after surgical interventions on the structures of the skull base reaches 6.2%, and after interventions on the structures of the anterior cranial fossa - 5.9%, middle cranial fossa - 6.4% and - 5.8% in all subtentorial interventions (Jamshidi, 2022; Rajendran, 2020). The aim of the study is to increase the effectiveness of surgical treatment of patients with tumors of the frontal sinuses with intracranial spread by using the method of high-frequency bipolar electric welding. Depending on the method of dura mater defect repair, patients were divided into 2 groups. The 1st group (control) included patients whose dura mater defect was connected according to the conventional method (suturing with polypropylene threads). In the 2nd group – the dura mater defect was connected by high-frequency bipolar electric welding. Patients of the 1st and 2nd groups were divided into 2 subgroups. Subgroups 1A and 2A included patients in whom the DM defect was up to 3 cm in diameter and linear; if necessary, a pericranium was used to close the DM defect. Subgroups 1B and 2B included patients in whom the connection of the defect was performed with the help of a fascia lata. As a result of the study, the authors proposed an effective method of connecting the dura mater defects after the removal of frontal sinus tumors spreading intracranially. Such methods include a high-frequency bipolar electric welding method, the use of which contributed to a minimal destructive effect on adjacent tissues but at the same time hermetically connected the dura mater. Presented data indicate that the use of high-frequency bipolar electric welding allowed to reduce the frequency of external CSFL by 2.2 times, compared to the use of suture material, and to reduce of hidden CSFL by 4.6 times, which indicates a statistically significant advantage of using high-frequency bipolar electric welding to close DM defects and prevent the occurrence of external and hidden CSFL in the postoperative period. In the presence of a DM defect of more than 3 cm and when it is closed with the fascia lata, it is possible to reduce the occurrence of external CSFL by 2.0 times compared to the control group. The use of high-frequency bipolar electric welding almost completely reduces the possibility of the formation of a meningeal scar in the postoperative period, which significantly accelerates the recovery of CSFL circulation and the recovery of brain tissue (due to the absence of factors that would irritate it), as a result of which the patient's rehabilitation and recovery are faster, compared to standard methods of connecting DM. The use of high-frequency bipolar electric welding was manifested by a faster recovery of normal intracranial pressure indicators - a faster recovery of fluid dynamics, a faster regression of inflammatory changes in the brain tissue and, as a result, a faster recovery of its functions, which indicates a higher quality of life of postoperative patients in the main group, compared to the control group.

Temperature Distribution of Vessel Tissue by High Frequency Electric Welding with Combination Optical Measure and Simulation.

In clinical surgery, high frequency electric welding is routinely utilized to seal and fuse soft tissues. This procedure denatures collagen by electrothermal coupling, resulting in the formation of new molecular crosslinks. It is critical to understand the temperature distribution and collagen structure changes during welding in order to prevent thermal damage caused by heat generated during welding. In this study, a method combining optical measurement and simulation was presented to evaluate the temperature distribution of vascular tissue during welding, with a fitting degree larger than 97% between simulation findings and measured data. Integrating temperature distribution data, strength test data, and Raman spectrum data, it is discovered that optimal parameters exist in the welding process that may effectively prevent thermal damage while assuring welding strength.

Morphological Assessment of Vascular Anastomoses Performed Using High Frequency Electric Welding

Morphological Assessment of Vascular Anastomoses Performed Using High Frequency Electric Welding

Histotopographic and morphometric characteristics of the oral mucosa postoperative wounds healing, depending on the method of connecting the wound edges

Implementation of high-quality tissue connections and hemostasis in oral surgery is an urgent problem of modern dentistry, due to the lack of available universal methods that would help to facilitate the work of oral surgeon and reduce wound healing time.
 The aim of the research. To investigate and study the regeneration processes in the oral mucosa after high-frequency electric welding, suturing and medical adhesive composition.
 Materials and methods. This study compared the effect of three connection methods and hemostasis: high-frequency electric welding (EKVZ-300M1 “PATONMED®”, Ukraine), suture method (nylon 5/0 “PIRUS®”, China), adhesive composition (“Histoacryl®”, Germany). 72 rabbits were involved in experiment. An incision of the soft tissues of the vestibulum of the oral cavity of the maxilla with a length of 1.3–1.5 cm was made. On days 3, 7, 14 and 21, tissue samples were excised, histological and morphometric examination of the material were performed.
 Results. By statistical data processing of 72 rabbits was found that the reliability of differences in the levels of morphometric parameters between groups on each day is very high, as evidenced by the calculated values ​​of the U-test. In 38 cases (90.5 %), the significance level was p≤0.01, in the other 4 cases – p≤0.05. The lowest value level of neutrophilic granulocytes was in rabbits of group No.1 (electric welding). In rabbits of group No. 1 GFBC were not observed in the 8 fields of view throughout the experiment.
 Conclusions. High-frequency electric welding of soft tissues can be used for effective intraoperative hemostasis and connection of the intraoral wound edges.
 Due to the absence of a foreign body (adhesive masses, filaments) and moderate alterative effect, histological examination indicates accelerated activation of regenerative processes in the early stages of observation in rabbits of group No. 1.

Дискуссионные вопросы высокочастотной электросварки биологических тканей

Цель. Исследование физических свойств составляющих биологических тканей и их роли в процессе электрической сварки мягких биологических тканей, а также измерение температуры в зоне электросварки.
 Материалы и методы. Исследования провели с использованием созданной системы для измерения температуры, состоящей из усилителя термо-ЭДС, внешнего модуля АЦП Е14-440 “Л-Кард”, ноутбука с программным обеспечением “PowerGraph”. Использовали также биполярный электрохирургический зажим и ВЧ-электрокоагулятор ЕК-300М1. Для имеющегося при сварке биологических тканей диапазона температур 40 – 200 °С выбраны термопары К–типа диаметром 70 мкм.
 Результаты. Проведенные исследования позволили установить, что сопротивление электролитов уменьшается, а проводимость - увеличивается с повышением температуры. Это объясняется тем, что с повышением температуры для слабых растворов увеличивается их диссоциация и, следовательно, число положительных и отрицательных ионов. Электропроводность цельных органов в 2 - 5 раз ниже, чем электропроводность биологических жидкостей. Поэтому при «полном» обезвоживании ткань практически теряет электропроводность, тепло в ней перестает выделяться и происходит резкое падение напряжения, силы тока и сопротивления, что предотвращает глубокие деструктивные изменения мягких тканей в зоне электросварки. Эти данные получены нами в процессе выполнения эксперимента по изучению температурных режимов тканей кишечника, мышечной ткани, легкого и печени.
 Выводы. Данными, полученными в ходе выполнения эксперимента, доказана безопасность высокочастотной электросварки мягких тканей в пределах температурных режимов от 45 до 95 °С без явлений некроза и обугливания.

EVALUATING VARIOUS METHODS OF LOCAL HEMOSTASIS IN THYROID SURGERY

The study involved 316 patients to assess the effectiveness of dif-ferent methods of local hemostasis and their combination during a surgery on the thyroid gland. The patients were aged from 14 to 82 (50,0±13,6 years). Women prevailed (85,8%). The first group (71) included patients in whom hemostasis was performed using traditional suture material. The sec-ond group (162) consisted of patients in whom hemostasis was carried out by means of HFEWM (High-Frequency Electric Welding machine EK300M1) and by ligation of superior thyroid vessels. In the third group, which included 83 patients hemostasis, additionally to HFEWM, was per-formed by applying the plate “Tahokomb” (Takeda Austria GmbH, Austria) to the site of bleeding or “Surgicel” (Ethicon, Johnson & Johnson, USA) in the place where the recurrent laryngeal nerve passes. It has been established that the combination of HFEWM with “Tahokomb” or “Surgicel” allows performing local hemostasis in the most effective way without postoperative complications.

Використання ВЧ-електрозварювання при лапароскопічній холецистектомії з причини гострого холециститу, ускладненого паравезикальним інфільтратом

У 20 хворих із гострим калькульозним холециститом, ускладненим паравезикальним інфільтратом, під час виконання лапароскопічної холецистектомії для дисекції тканин та гемостазу використовували метод високочастотного електрозварювання. Застосування даного методу при дисекції дозволило значно зменшити кровоточивість інфільтрованих тканин за рахунок того, що відбувалося заварювання всіх дрібних судин та капілярів і розсічені тканини майже не кровоточили. У випадках виникнення кровотечі метод ВЧ-електрозварювання, на відміну від монополярної коагуляції, дозволяє проводити гемостаз без постійного осушення операційного поля. Крім того, даний метод дає можливість проводити гемостаз як із дрібних капілярів, так і з судин більш великого діаметра, в тому числі з міхурової артерії. У результаті використання ВЧ-електрозварювання вдалося полегшити дисекцію тканин, покращити ідентифікацію структур зони трикутника Кало та значно скоротити час операції.

Сравнительная эффективность витректомии с использованием для ретинопексии высокочастотной электросварки биологических тканей и диодной лазерной коагуляции в лечении больных регматогенной отслойкой сетчатки

Сравнительная эффективность витректомии с использованием для ретинопексии высокочастотной электросварки биологических тканей и диодной лазерной коагуляции в лечении больных регматогенной отслойкой сетчатки

Controlling and Monitoring of Welding Parameters for Micro-Alloyed Steel Pipes Produced by High Frequency Electric Welding

Manufacture of steel pipes micro-alloyed with Ti, V, Nb by high frequency electric resistance welding (HF-ERW) is a modern and efficient method, but requires a good knowledge and adjustment of various parameters influencing the welding process. This study aims to determine the influence of the main process parameters (electrical and mechanical) and establish correlations between them, in order to optimize the welding process. This was possible only by controlling and monitoring the welding parameters used and conducting experiments and tests on welded pipes in different conditions.

High-frequency electric welding: a novel method for improved immediate chorioretinal adhesion in vitreoretinal surgery.

To evaluate high-frequency electric welding (HFEW) as a novel technique for retinopexy with improved immediate chorioretinal adhesion In a prospective, randomized, experimental study, we examined 104 eyes of 52 rabbits randomly assigned to either standard 810 nm endolaser retinopexy, alternating current 14-16 V or 18-20 V HFEW retinopexy. A full-thickness fragment of eye wall tissue containing the retinopexy was isolated 1 h, 3 days, 1 week, or 1 month respectively after the intervention, and fixed to an analytical electronic scale. A nylon suture passed through the retina was elevated by a biomechanical force elongation tester. The reduction in weight at the time of retinopexy rupture was registered as a measure for retinopexy adhesion strength. One hour post-exposure, adhesive strengths were significantly higher in both HFEW groups than in controls (212 ± 26.6 mg and 122 ± 16 mg vs 104 ± 10 mg; p = 0.0001 and p = 0.024 respectively) while laser retinopexy did not significantly change adhesive strength (114 ± 14.0 mg, p = 0.149). Subsequent adhesive strengths were significantly increased for all retinopexy techniques: 3 days post-op 14-16 V HFEW 224 ± 30.0 mg (p = 0.001), 18-20 V HFEW 128 ± 15.6 (p = 0.001), laser 131 ± 12.7 mg (p = 0.0007); at 1 week 14-16 HFEW 235 ± 24.7 mg, 18-20 V HFEW 213 ± 22.4 mg, laser 188 ± 18.7 mg (all p ≤ 0.001); 1 month post-op 14-16 V HFEW 275 ± 32.0 mg, 18-20 V HFEW 283 ± 31.0 mg, laser 276 ± 21.7 mg, rspectively (all p ≤ 0.0001). HFEW represents a novel technique for retinopexy during vitreoretinal surgery. It allows firm chorioretinal adhesion immediately after exposure. In non-vitrectomized eyes, using 14-16 V is particularly effective.

Влияние высокочастотной электросварки биологических тканей (модифицированный генератор ЭК-300М1) на длительность кровотечения из магистральных сосудов сетчатки при моделировании внутриглазного кровотечения у кроликов по сравнению с диатермокоагуляцией

Влияние высокочастотной электросварки биологических тканей (модифицированный генератор ЭК-300М1) на длительность кровотечения из магистральных сосудов сетчатки при моделировании внутриглазного кровотечения у кроликов по сравнению с диатермокоагуляцией