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...Welding technology is advancing victoriously on the ground,
in the underwater world and in space.
Welding is starting to advance in the medical field.
It is used with success for joining damaged human tissues and restoration of the functioning
of human organs.
Prof. B. Paton
PROJECT "
WELDING OF LIVE TISSUES"
(brief information)
High-frequency electrosurgery has found a rather wide application in medicine. It is used to dissect tissues and to stop or prevent bleeding when tissue and blood vessels are incised. After that the operated organs inevitably lose their functions, which are not restored when the patient recovers.
E.O. Paton Electric Welding Institute of the National Academy of Sciences of Ukraine (NASU) addressed the problem of bonding incised soft tissues using the high frequency electrosurgery methods. The main requirements were to enable joining an incision of a live tissue without use of suture material, staples or suturing devices, as well as restoring physiological functions of the welded tissue and maintaining the vital functions of the injured organ. In 1993, on the initiative of academician Boris E. Paton, the employees of E.O.Paton Institute together with the surgeons of the Institute of Clinical and Experimental Surgery of the Academy of Medical Sciences of Ukraine, and Medical Association «OKHMATDET», carried out experiments which proved in principle a possibility of making a weld on various soft animal tissues using bipolar coagulation method. In 1996 systematic research of this tissue joining method was started. Consortium Service Management Group, Inc. (CSMG), a US company from Corpus Christi, Texas, headed by Mr. Donald S. Robbins, became involved in solving this problem through the International Association Welding. CSMG in their turn attracted to this work a group of American surgeons. In 1997 the Ukrainian experts demonstrated welding of soft animal tissues to US experts at the Research Center of Cristine M.Kleinert Institute of Arm Microsurgery in Louisville, USA. The demonstrated surgeries in the field of general surgery and microsurgery attracted great interest.
An international team was formed to develop the «Live Soft Tissue Welding» project, in which the scientists and experts of the above Ukrainian and US organization participated. In 1998 experiments on welding the tissues of removed human organs started at the Security Service Army-Medical Administration Hospital of Ukraine in Kiev. In order to preserve the physiological properties of the tissue, these experiments were carried out immediately after the organs had been removed under the clinical conditions. These experiments were preceded by surgical operations, using the welding technology on more than 1000 test animals (white rats, rabbits, dogs and pigs). This work was carried out at the Experimental Department of the Institute of Surgery and Transplantology of the Academy of Medical Sciences of Ukraine.
At E.O.Paton Electric Welding Institute of NASU the conditions of formation of tissue weld using the high frequency electric currents have been determined, and a welding system meeting these requirements has been developed, which includes a power unit, consisting of a power source (HF coagulator) with a control system and special software, bipolar welding tools (forceps, clamps and laparoscopes) connected to the power source, and special assembly devices. The welding process control system operation is based on feedbacks.
The power source is connected to 220 V mains of 50 Hz frequency.
Its maximum power is up to 500 VA;
maximum voltage is 280 V;
maximum frequency is 440 Hz;
overall dimensions are 300x160x220 mm
and weight is 16 kg.
The basic phenomena, which proceed in soft tissue welding, can be schematically described as follows. The tissue layers being joined are brought into contact over their surface layers by means of a welding tool. Then the surgeon clamps the tissue area to be welded by the electrodes of the welding tool and switches on the welding current source. When the welding process control program is completed and the power is turned off, the clamped tissue is released, and then the process should be repeated until the wound is closed completely.
 The method of weld formation is based on the effect of electrothermal denaturation of albumen molecules.
To make restoration of physiological functions of a damaged organ fast and uncomplicated the thermal input should be as small as possible, but sufficient for making the bond. Thus, the requirements to control of the welding process become significantly higher. On the other hand, it is important that the control process be easy for the surgeon. He should not be distracted by adjustment of the equipment or lose any time doing it. For this purpose an adaptive automatic control system of the welding process has been developed and successfully used.
For the welding technology to be approved for wide introduction into clinical surgery, it was necessary to have reliable data on consistently repeatable results of its application. This data could be obtained only on animals. Euthanasia of the operated animals, performed after different postoperative periods, and after proper studies of weld preparations, could reveal the healing and recovery picture of the tissue affected by heat. For this purpose experimental work on a large group of animals (rats, rabbits, dogs, and pigs) was conducted with subsequent histological studies of preparations taken after different postoperative periods (14, 30, 60, 90 and 180 days). The main postoperative assessment criteria of repeatability of sound welds were: inflammation, epithelization, thickening of the wall and deformation of the wall. Evaluation of the welding technology application was performed during operations on the intestines, liver, and gall bladder. Analysis of the experimental data enabled the researchers to make a conclusion that 30 days after the surgery there was a steady absence of inflammatory processes. Separate tissue structure fragments of preparations studied after different postoperative periods are given.
Based on the results of conducted experiments, the following procedures were optimized for welding technology application during surgeries on pigs:
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using bipolar welding forceps to join longitudinal incisions of serous and submucous membranes and muscular tissue of part of a large intestine by a spot weld achieving complete tightness;
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formation of a circular anastomosis on large intestine by making a one-row sero-serous weld. The weld was completely tight, which was confirmed by a postoperative autopsy done three months after the surgery. The weld area was hardly detectable;
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making a tight weld of a longitudinal incision of the gall bladder. A 6–7 mm spot weld was produced, using bipolar welding forceps.
Based on the consistently repeatable positive results obtained from all the experiments both in the control group of animals (pigs) and those performed on the removed or to-be-removed human organs, the Ministry of Health Ukraine issued a Certificate of State Registration of the welding equipment application in the medical practice.
This enabled conducting clinical trails of the welding process in the general surgery and gynecology field at the Security Service Army-Medical Administration Hospital together with the scientists and specialists from B.E.Paton Electric Welding Institute NAS Ukraine.
 Clinical trials of the welding technology with the engineering supervision of E.O.Paton Institute specialists are currently performed also at the Institute for Surgery and Transplantology and Institute of Neurosurgery of the Academy of Medical Sciences of Ukraine, at the Surgery Ward of Kiev City Clinical Hospital #1 and Polytrauma Ward of Kiev City Clinical Hospital #17.
As of November, 2003 over 1500 surgeries had been performed on various human organs. No postoperative complications or haemorrhages were found in any of the cases of application of the new welding medical equipment.
Patents of Ukraine, USA and Australia were taken for the process of live tissue welding, including the automated welding medical equipment and tools.
 Strength testing of welded joints on the removed hollow human organs produced the following results.
It has been established that the effects on the live tissue produced by the welding technology and the widely applicable coagulation process are different in principle. The coagulation process causes tissue burns and necrosis in the area of heating impact, while use of the welding technology leads to much smaller traumatic effect on the tissue and causes no burns which was proved by morphology studies, as well as absence of fumes or odor during the welding process. The welded tissue was not damaged which favors faster and easier healing of the tissue of the operated organ, recovery of its morphological structure and functions.
A feature of the developed welding technology with application of the above-mentioned welding systems is the versatility of their application in surgery. Unlike LigaSure system of Vallay Lab Company our technology with application of one welding system enables performance of coagulation, closing up to 8 mm vessels, incision of tissues, including muscular, fatty, vascular, parenchymatous, pulmonary, ligaments, etc., producing tight and sufficiently strong bonds of tissue incisions with minimum loss of blood by applying longitudinal and circumferential welds using forcepts, in single-moment and double-stage mode using special clamps. This process and equipment have found clinical application both in surgical endoscopy and laparoscopy. In a number of cases surgery proceeds without applying ligature or clips. The process is already applied in operations of general surgery, gynecology, pulmonology, neurosurgery and reogengology.
It should be noted that the new surgical technology can become widely accepted both for post-trauma operations on healthy, but injured tissue, and for treatment of chronic diseases, when plastics or reconstruction of the organs after removal of the affected tissue areas are required.
Our experience shows that application of the welding technology provides an attractive weld: thin, smooth, neat, which does not deform the organ or make the lumen of hollow organs narrower.
The bond in the weld area is completely tight and aseptic. Application of welding technology facilitates the surgical technique proper.
The new welding medical equipment when used in surgery provides a fumeless technology, unlike the known coagulation method. This is favourable for surgeon's health, particularly when working with infected patients.
The following surgical operations conducted on humans, can be cited as examples of techniques used during surgeries with application of the welding technology with positive results obtained in experiments on big animals and under clinical conditions on human patients (first on the removed and to-be-removed organs and then directly on human patients):
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performing plastics of the fallopian tubes and restorative surgeries;
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capability of achieving fast and reliable hemostasis, obtained in the subcutaneous fat, paracervical fat, during dissection of commissures, ligaments of the fallopian tubes, without application of surgical clamps, needles, ligatures;
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making a reliable and perfectly tight bond obtained when a lumen is closed in the ureter, which prevents reflux (throw of urine from the urinary bladder) or development of urinary flows;
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capability of making a reliable tight weld on the stomach, fast and bloodless separation of the stomach, resection of the omentum, tight welding and cutting off of the stomach and the duodenum, without any risk of the infected contents penetrating from their lumen to the abdominal cavity;
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during appendectomy performance of one-stage welding without suturing and ligation, hemostasis and treatment of the appendix stump. This enables conducting bloodless surgery, preventing such complications as infiltrates, formed when the remaining collaterals are ligated;
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during cholecystectomy performance of surgery without blood loss or bile efflux;
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applying a weld to provide in one manipulation a quick and reliable sealing of a defect in a damaged gall bladder wall, i. e. wall restoration; prevention of bile penetration into the abdominal cavity during laparoscopic surgery; elimination of bile and blood leakage from the edges of the wound;
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capability of applying a tight weld on the intestine, in particular to seal it off;
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in surgery of the nasal and mouth cavity capability of restoration of the continuity of the nasal septum mucous, as well as tonsillectomy, using special welding tools.
Results of clinical application of the welding process demonstrate the possibility of alleviating post-operative pains, simplicity and safety of application of the developed equipment, considerable shortening of surgery duration (up to 60 minutes in some cases) after which recovery is faster and easier.
Application of the welding technology significantly reduces the loss of blood, e.g. during hysterectomy the blood loss is reduced by 200 ml to 300 ml. Surgery is done on «dry» operating field.
Cost benefits are obvious. Suture materials and clips are practically not used, as the bond is formed by the material of the welded organ proper. Shortening of surgery duration and recovery period leads to reduction of medicine costs, in particular for narcotic drugs.
All the above-said leads to the conclusion that a new step in the development of electrosurgery was made within the framework of the Soft Live Tissue Welding project.
In terms of organizing the work, the distribution of responsibilities of the parties within this project is as follows:
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E.O.Paton Institute of the NAS of Ukraine, in cooperation with the above-mentioned medical establishments of Ukraine, performed development and manufacture of experimental samples of welding equipment, software for the control system, welding tools and mastering of the procedures for producing restoration welds of damaged organs with validation of their quality;
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CSMG Company, USA provided funding of the project work and patenting of the technology and new developments.
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International Association Welding addresses management, financial-economic and legal issues in compliance with the requirements of the Ukrainian legislation, puts together programs and forms joint teams of specialists of both engineering and medical profile to address the goals of Soft Live Tissue Welding Project.
The soft tissue welding technique is at the stage of wide clinical application. Fields of its application are gradually widened, surgical techniques are being improved allowing for the specifics of tissue welding technology.
In the near future, it is intended to master the following new procedures of the welding technology:
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restorative surgery in gynecology: making circular anastomoses, at Fallopian tube recanalization, making circumferential and longitudinal anastomoses in Fallopean tube plastics;
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formation of large-intestinal and small-intestinal anastomoses, as well as gastrointestinal anastomoses when performing endoscopic and laparoscopic surgery;
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when bonding skin incisions after laparoscopy and other operations;
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reconstructive surgeries in case of deep vein disorders and application of anastomoses on the veins (end-to-end, telescopic longitudinal);
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surgery in urology;
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cosmetic surgery on mammary glands, abdomen and chest, lower and upper extremities;
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resection of lung tumor in pulmonological surgery, extracelebral tumor in neurosurgical operations, as well as liver tumor in oncological operations.
The new data obtained during surgery will be used for retrofitting and widening the range of welding tools, improvement of the technique of its application and development of special equipment to solve various surgical problems.
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Welding of Live Tissues