RU2517052C1 - Method for inert gas plasma coagulation using krypton spray - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: exposure is generated by a high-frequency spray generator with the working inert gas krypton supplied onto a handle nozzle. The gas is ionised by a high-frequency current discharge; a krypton plasma torch passing from an active pin electrode to a coagulated tissue is generated.

EFFECT: method enables providing the more reliable hemostasis as compared to the argon-plasma coagulation, reliable coagulation of the vessels of a greater diameter, a lesser depth of thermal necrosis and parabiosis that further leads to the faster clinical course of the wound process and regeneration to form a softer and mature scar with clear signs of re-modelling.

1 dwg, 2 tbl

Description

FIELD OF THE INVENTION

The invention relates to medicine, in particular to surgery, endoscopic surgery, obstetrics and gynecology, dermatocosmetology, otorhinolaryngology. The invention can be used to achieve reliable hemostasis with gentle coagulation of deep tissue, as well as for the surface destruction of pathological structures of coagulated tissues of both hollow and parenchymal organs.

A known method of fulguration [1], which is limitedly used in surgery, dermatocosmetology. The method consists in the contactless monopolar effect of high-frequency current energy on the tissue. During fulguration, the electrode does not touch the tissue, an electric arc forms between the tissue and the electrode, the length of which varies from 1 to 10 mm, depending on the applied voltage. The consecutive occurrence of such discharges allows achieving surface destruction of pathological structures in a certain area.

The disadvantages of this method include:

1) limited use on the hollow organs due to the scab heterogeneity during uneven coagulation, which can cause arrosive bleeding;

2) the restriction of use in endoscopic surgery due to the random distribution of discharges, which depends on the orientation of the instrument relative to the coagulated tissue;

3) fulguration is accompanied by the formation of smoke and odors.

Also known is a method of argon plasma coagulation (ablation) (APC) [2]. The APC method selected as a prototype is a method of monopolar high-frequency surgery, in which the energy of an electromagnetic field of a high frequency is transferred to the tissue in a non-contact way using ionized gas - argon. The electrosurgical unit generates a high-frequency electromagnetic field between the two poles - one of which is an active electrode, which is in the surgeon's hand, and the other is a passive electrode (a plate that is applied to the patient’s body). When the active electrode is blown with an inert gas - argon, gas ionizes with the formation of an argon plasma torch. Through this torch, the energy of the high-frequency electromagnetic field is contactlessly transmitted to the underlying tissue site.

Under the influence of plasma, local heating and coagulation (ablation) of tissue occur. When a coagulant layer is formed, the electrical resistance of the tissue increases and further penetration of the process into the depths automatically stops, the torch shifts to non-coagulated (having lower electrical resistance) tissue sections. A uniform surface layer of coagulant is formed. This process occurs until uniform ablation of the entire exposure zone is achieved. Depth of ablation does not exceed 3 mm and depends on the installed capacity and duration of exposure.

AIC is widely used both in "open" and in endo-, laparo-, thoracoscopic surgery, as well as in surgical obstetrics and allows to achieve hemostasis of extensive bleeding surfaces of parenchymal and hollow organs. In addition, the prototype method is used in endoscopic surgery, gynecology, dermatocosmetology, otorhinolaryngology, urology and oncology for the treatment of surface tissues of the skin, oral and nasal cavities, organs of the gastrointestinal and urogenital tract and leads to their replacement with healthy tissues.

The disadvantages of the prototype include:

1) a deeper thermal damage to the coagulated tissue;

2) a slower course of the wound process compared with the proposed method;

3) the scar after argon-plasma coagulation is less mature, has a large size.

Disclosure of invention

The objective of the invention is to achieve a better hemostatic effect with less deep thermal damage to the tissue, as well as a more superficial destruction of the pathological structures of the coagulated tissue, a significant acceleration of the course of the wound process and regeneration of the tissues being treated, with the formation of a more mature remodeled scar using kryptoplasma coagulation.

The authors experimentally found that the tasks are solved due to the fact that in the method of inert gas-enhanced plasma coagulation using krypton in the "spray" mode, which includes ionizing krypton with high-frequency current discharges, which form a kryptoplasma stream, which causes surface coagulation of the tissue, as a working The body uses krypton instead of argon, which is used in the prototype method.

The essence of the proposed method lies in the contactless monopolar electrosurgical effect of the torch of krypton plasma on the tissue site to be affected (Figure 1). To create a plasma arc, the electrosurgical generator (HF) simultaneously delivers an inert gas krypton (Kr) at a certain speed to the nozzle of the handle (2) located at a certain distance (d) (up to 10 mm), as well as a high-frequency current (I _HF ) in spray mode to the active needle electrode (1) located inside this nozzle. At this moment, krypton is ionized, a directional conical plasma flow (3) forms from the tip of the active electrode to the tissue (4), the surface of which coagulates (6). The neutral electrode closes the electric circuit (5).

Between the totality of the essential features of the claimed object and the achieved technical result, there is a causal relationship based on the differences in the physicochemical characteristics of the inert gases of argon (Ar) and krypton (Kr) used as a working fluid for inert gas-enhanced plasma coagulation in the spray mode (Table 1).

The technical result.

The method of inert gas-enhanced coagulation using krypton in the "spray" mode allows you to improve the results of exposure to tissue compared with the results of exposure to tissue of the prototype for a number of characteristics (Table 2).

The possibility of carrying out the claimed invention is shown by the following example.

Example 1

In the period from June 2010 to August 2012, in the conditions of the experimental laboratory of the SBEI HPE Tver State Medical Administration of the Ministry of Health of the Russian Federation, research and experimental work was carried out, during which pork liver preparations as a working medium for inert gas-enhanced plasma coagulation in In spray mode, krypton was first used in parallel with argon.

Chronic experiments were conducted on laboratory animals - 10 piglets of the same breed, female weighing 10 ± 2 kg. In conditions of lower thoracic epidural anesthesia against the background of sedation with phenozepam, the upper middle laparotomy was performed in the experimental operating room. On the liver, in the region of its edge, with a standardized cylindrical instrument with a diameter of 10 mm, 12 injuries of the same type were inflicted, which were subsequently subjected to inert-gas-enhanced plasma coagulation using krypton in the spray mode (krypton-plasma coagulation (CPC)) and argon-plasma coagulation (APC) to achieve complete hemo- and cholestasis.

For histological examination, the material was taken using a standardized cylindrical instrument with a diameter of 15 mm at the time of surgery and during a relaparotomy on the 1st, 3rd, 7th, 14th and 30th days. Microscopic examination of liver tissue preparations obtained at the time of surgery from the wound surface area exposed to the electrosurgical effects of APC and CPC revealed the same tissue reaction in all experimental observations. At the same time, the thickness of the zone of necrotic and necrobiotic changes significantly varied and depended on the type of inert gas used: argon - 2.2 ± 0.3 mm, krypton - 0.6 ± 0.1 mm. The infiltrate separating necrotic tissues consisted of sparsely located polymorphonuclear leukocytes, the bulk density of which during morphological examination was 12.3 ± 1.9 in the case of APC and 6.1 ± 1.1 in case of CPC, respectively. The wound surface under both types of exposure over a significant area was covered with a thin scab consisting of red blood cells, white blood cells and desquamated hepatocytes. Its thickness varied within 2.1 ± 0.3 mm for APC and 0.2 ± 0.02 mm for CPC, respectively. When using APC in the underlying areas of the liver tissue at a depth of 2-4 hepatic lobules from the wound surface, ectasia of the hepatic veins, the phenomena of hydropic dystrophy of the parenchyma, moderate swelling of the connective tissue layers and peripheral diapidetic hemorrhages are noted. When using the PDA, these changes were absent or were insignificant.

On the 1st day, the bulk density of leukocytes at the border of the necrosis zone was 18.3 ± 1.6 for CPC and 47.6 ± 2.3 for APC, respectively. When using the APC, monocytes and macrophages appeared in the demarcation zone within a day.

Seven days later, upon microscopic examination, the total zone of necrotic changes increased and became denser due to the fusion of the zone of primary necrosis and the zone of necrosis reserve, regardless of the type of gas-plasma exposure. And when using the CCP, it was 1.4 ± 0.2 mm and 6.4 ± 0.4 mm for the AIC, respectively. The bulk density of capillaries at this experimental period in the case of APC and CPC was 3.9 ± 0.3 and 2.2 ± 0.4, respectively.

On the 14th day, a significant number of multinuclear giant cells of the macrophage series remained in granulomas, the number of which in APC was several times higher than the number of similar elements when exposed to CPC (27.6 ± 2.1 and 10.3 ± 1.7, respectively). Compared to the 7th day of observation, the bulk density of active capillaries decreased by half, while by CPC, by a factor of three, and amounted to 2.1 ± 0.5 and 0.8 ± 0.3, respectively.

On the 30th day, the surface of the gas-plasma exposure zone was covered with a formed delicate scar tissue of various thicknesses: with APC 3.4 ± 0.8 mm, with CPC 0.9 ± 0.2 mm. It should be added that when using krypton, the scar was distinguished by clear signs of maturity and remodeling.

Thus, krypton can be used as a working fluid in gas-plasma coagulation. Significant acceleration of the course of the wound healing process and regeneration with the formation of a more tender remodeled scar when using inert gas-enhanced plasma coagulation using krypton in the spray mode is noted.

List of references

1. Lurie R.G. About histological changes in normal tissues and those affected by cancerous neoplasms under the influence of fulguration. // Journal of Obstetrics and Women's Diseases. - SPb. - 1909. - S. 1285-1292.

2. Oboskalova T.A. et al. Treatment of benign diseases of the cervix, vagina and external genital organs by methods of broadband radio wave surgery and argon plasma ablation. Toolkit for doctors. - Yekaterinburg. - 2007. - P.9, 10, 13, 20.

Table 1 Working body Atomic mass Ionization energy (eV) Ion radius (pm) Ar 39.95 15.75 154 Kr 83.8 13,99 169

table 2 Method of exposure Scab thickness after coagulation (mm) Scar thickness on the 30th day (mm) Prototype 2.1 ± 0.3 3.4 ± 0.8 The proposed method 0.2 ± 0.02 0.9 ± 0.2

Claims (1)

A method of inert gas-enhanced plasma coagulation using krypton in the "spray" mode, comprising applying a high-frequency generator to supply a working inert gas to the handle nozzle, ionizing the gas with high-frequency current discharges, forming a conical plasma torch passing from the active needle electrode to the coagulated tissue, characterized in that as a working inert gas using krypton.

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