WO2007032017A2

WO2007032017A2 - Devitalizing viruses in medical laser plumes

Info

Publication number: WO2007032017A2
Application number: PCT/IN2005/000410
Authority: WO
Inventors: Hamish Chandru Shahani
Original assignee: Hamish Chandru Shahani
Priority date: 2005-09-14
Filing date: 2005-12-13
Publication date: 2007-03-22
Also published as: WO2007032017A3

Abstract

A surgical laser smoke evacuator, with in-line plasma devitalization of viral bio-entities and their capture system, comprising a medical ablation laser probe, co- axially disposed inside a plume aspirator carrying the airborne biological debris, from vaporized tissue past a viral deproteinization plasma generator onto a high efficiency particulate immobilization cartridge, is disclosed. These components, in combination, ensure that the assembly yields a virus-free exhaust that prevents cross-infection from the patient to the medical personnel. The diaphragm air pump replaces the conventional motor blower and vacuum pump, which have numerous particulate lodgment sites, and makes the apparatus of this patent, sufficiently compact and portable, so as not to require the usual operating room space. It also does not interfere with the free movement of medical personnel. The single hand-piece, functioning both as the ablation probe and aspirator, enables the surgeon to do without an attendant, who has to track synchronously the surgeon's movement during the invasive surgery, when conventional devices are used.

Description

FIELD OF THE INVENTION

The present invention relates to the field of biohazards affecting medical personnel who utilize lasers for ablative procedures. While performing various forms of laser surgery and electro-cauterization, airborne fumes and particles are usually generated as debris. That debris stems from volatilized tissue, in the form of a plume rich in viable microbial content. Those disease-causing bio-entities can be viral and bacterial and can linger as biota in the zone of operation, if allowed to remain airborne in the operating room, can diffuse into the room space and may settle into the open wounds of the next patient being operated on, potentially resulting in the transmission of that disease to that patient or even the operating personnel. It is known that at least one species-Human Papilloma Virus, with its discrete size about 50 nanometers, does survive the laser surgery procedure and causes cervical cancer when it lodges in the body . Of potentially greater concern is the HIV virus that causes AIDS, which may remain in the room air, virulent for brief periods, where the medical procedure has been performed. There is also a risk of AIDS transmittal by aerosolized blood and tissue disintegrating from laser procedures where HIV survives for a longer period.

To bring out the essence of the novelty and of the originality of this invention, it is imperative to expound and bring into context two domains of prior art.

DESCRIPTION OF PRIOR ART

DOMAIN ONE

Invasive laser surgeries are increasingly used by the medical profession for treatment in gynaecology, including cervical dysplasia, venereal warts, endometriosis, fallopian tube procedures and vulvectomys.

In the field of dermatology, laser procedures have been used to remove stains, tattoos, treat fungal conditions, and also the removal of birth marks. Lasers are also being used in podiatry for fungal nails, plantal warts, bunionectomys, and neuroma removal. In addition to carcinoma of the larynx in the pulmonary field and also for endotracheal growth vaporization. Brain tumors are also being excised by lasers during neurosurgery.

Unfortunately, the use of laser surgery is also accompanied by the generation of large amounts of gas-phase contaminants and viral aerosol from irradiated tissues.

It is obvious that without special protective measures, biohazardous sub-100 nm size particulates resulting from laser ablation could rise to unacceptable levels.

In accord with the teachings of U.S. PAT 5,409,511 and U.S. PAT 5,047,072 which are cited here and the disclosures of which are incorporated by reference, these patents and the others in the referral list constitute prior art contrivances to evacuate airborne contaminants volatilized from laser surgeries to safeguard the operating personnel from cross-infection by immobilizing microflora in the filter matrix but not devitalizing them in any way. Invariably all prior art attempts have been to provide useful entrapment of the biological refuse by high-efficiency filtration deeming that method as adequate for LOG 6 biosecurity against viral contagions, without taking care of the density and volume of oxidized tissue aerosol rich in cell-moisture which is dispersed in the operating room. That can reach a concentration of 8 PPM of potentially mutagenic and probably carcinogenic organisms that threaten surgical personnel who are repeatedly exposed to diverse species of microflora from different patients.

U.S. PAT 5,409,511 laser plume removal system is a ceiling mounted evacuation system utilizing articulating arms and also comprising central components of the system such as a centrifugal separator tank, garbage pump, optional disinfectant tank, vacuum producer and HEPA filter. The operating room is connected to the central components by a piping system that has branch takeoffs that serve numerous outlets. The piping system includes the flexible plastic tubing, as well as a permanent rigid piping. The suction opening, that has to be proximate to the laser target site, is connected to tubing located within the articulating arm. This tubing is flexible to allow for movement and rotation of the arm without disturbing the position of the suction throughout the electro-cauterization process. The inner walls of the tubing must be smooth so debris cannot build up and dislodge and fall back by gravity to the suction aspirator. The central system components are located in a mechanical room, connected to the operating rooms served by the laser plume evacuation system. The piping mains join together and are connected to the centrifugal separator tank. The tank separates debris picked up by the system from the air passing though the system. The airborne medical refuse, which includes vaporized tissue particles and bone dust is flushed out of the tank, through a small garbage pump, and into the sanitary sewer system. These mobile units recirculate the air back into the operating room, where microscopic particulate matter below 0.1 micron can escape the filtration process and remain suspended for the next operating procedure. An activated charcoal filter is provided before the final high efficiency particulate filter. Air leaves the top of the separator tank and is drawn through the vacuum producers before entering the HEPA filter which captures particles of size 0.3 micron and greater, before air is discharged to the ambient.

U.S. PAT 5,047,072 discloses a mobile evacuation unit with means to disinfect the extract air by passage over germicidal UV lamps upto 6000 microwatts per square centimeter, by and as of itself inadequate as a virucidal process. UV light is effective only on vegetative bio-entities. No attempt is made to deal with the deadly 50-100 nanometer size viral pathogens such as HPV₁ HIV and endotoxins that threaten those occupying the operating room.

It is evident that none of these patents show concern about the primacy of a virus- free operating room environment which is a prerequisite for medical personnel carrying out invasive surgical procedures.

DOMAIN TWO

Many processes have been proposed or used for devitalization of viral pathogens and endotoxins by dry heat depyrogenation, ionizing radiation and electron beams.

NASA's outer space planetary protection policy is dedicated to elimination of viral spores from direct-contact landers, rovers and probes. Their exhaustive investigations have justified the use of plasma sterilization at their Ames Research Centre, Moffet Field, CaI 94035 where significant and successful methodologies have been evolved and many studies published. One of those reports relating to in-flight removal of viable biological and organic matter from the spacecraft anticipates the use of Martian atmosphere for generation of sterilization plasma, is included in the citation list as it substantiates this patent.

U.S. PAT 5,633,424 and U.S. PAT 6,853,142 disclose methods and apparatuses for generating plasma at atmospheric pressure, for deproteinization and rendering sterile airborne viral pathogens. Pathogens are cells containing cytoplasm, a colloidal system of large biochemicals in a complex solution of smaller organic molecules and inorganic salts. The cytoplasm is bounded by a semi-elastic, selectively permeable cell membrane that controls the transport of molecules into and out of the cell. There are biochemical transport mechanisms that spend energy to bring substances into the cell despite unfavorable concentration gradients across the membrane. Cells are protected by rigid cell walls external to the cell membranes. Certain bacteria, algae and protozoa have gelatinous sheaths of inorganic materials such as silica.

Sequence of genes along a thread like chromosome encodes information that controls cellular activity. As units of heredity, genes determine the cellular characteristics passed from one generation to the next. In most cells the chromosomes are surrounded by a membrane to form a conspicuous nucleus. Cells with organized nuclei are described as eukaryotic. Other intracellular structures serve as specialized sites for cellular activities. Photosynthesis is carried out by organelles called chloroplasts. In bacterial and cyanobacteria the chromosomes are not surrounded by a membrane and there is little apparent sub-cellular organization. Lacking a discrete nucleus, these organisms are said to be prokaryotic. Exposing these organisms to sterilizing agents such as mustard chemicals, ultraviolet light or plasma increases mutation rate by damaging chromosomes.

By accelerating mutagenesis with a gas plasma discharge the idea is to inactivate all organisms including endotoxins. The DNA molecule has a spiral chain link configuration with a variety of chemical links between the longitudinal members. This cross-linked construction permits the establishment of a variety of circulatory currents in different paths. The various paths having different resonant characteristics permitting selective modification in the DNA molecule by subjecting it to excitation at a frequency or frequencies which establish currents in some paths but not in others.

Devitalization relies on exposing the bioburden within the laser plume to a continuous flow of gas plasma. Around the plasma, free electrons gain energy from the imposed electric field and lose this energy through collisions with neutral gas molecules. The energy transfer process, besides dissociating cell-contained moisture, leads to the formation of a variety of highly reactive products including metastable atoms, free radicals and ions.

In the case of high resistance spores, the photonic action may contribute to partial alteration of the disulphide rich protein coat, thus facilitating the diffusion of free radicals, atoms, or excited molecules inside the core region. At about 3.3 eV, the high energy protons will produce strong virucidal effects because they correspond to a maximum of absorption by DNA and other nucleic acids. In the case of sub-micronic spores, photon energy is quickly dissipated through the various spore layers which may restrict photochemical reactions to outer coats.

Such a discharge can be generated by a plasma torch disclosed by U.S. PAT 6,329,628 by means of which a number of excited species, both molecular and atomic, are formed. Mounted as in an array, this plasma torch module is disclosed for deployment to absorb radiation to cloak air craft against enemy radar detection and also to reduce air drag and attenuate sonic boom. This patent has been cited as prior art as it is germane to the construction features of the plasma torch being used by this invention. Most plasma lend themselves to the devitalization mode of operation, since the effectiveness of neutrally active species generated in such a discharge persists substantial distances downstream, away from the cavity itself. This is a direct consequence of the higher concentration of electrons in plasmas and the higher degree of ionization and atomic dissociation in these discharges. Plasma electric probe measurements indicate that plasma potentials are nearly equal to ground potential, thereby practically eliminating energetic particle bombardment/αuring processing. This mode of operation is thus well suited for low temperature exposure of heat- labile devices and material, even for extended periods of sterilization time. The interaction of the ionic species generated by the plasma torch with the laser plume extract comprising vaporized tissue accomplishes the devitalization and inhibits viral reproduction in the manner described above. The time duration of the process needed to achieve satisfactory devitalization will vary with other parameters of the discharge such as gas flow, pressure, power density, viral load size.

The five patents cited above as also their research data and literature sources are incorporated in this patent by reference.

LIMITATIONS OF PRIOR ART

U.S. PAT 5,409,511 and U.S. PAT 5,047,072 have delved into medical lasers and each in their own manner have provided methods and means to sub-serve their objects with incomparable grasp of detail and function. Each of these disclosures and those in the citations list has singular distinguishing attributes; but none has conceived or demonstrated viral devitalization to inhibit bio-risks to medical personnel and patients arising from airborne viral contagions stemming from laser surgical procedures.

SUMMARY OF THE OBJECTS OF THE INVENTION

The main object is to provide a laser plume evacuation system that ensures devitalization and capture of airborne microflora, particularly viruses, resulting from laser vaporization of cells, thus greatly reducing the likelihood of transmission by communicable pathogens, from the surgery site to those medical personnel who are in close proximity; achieving that object by creatively integrating methods and means invented independently in two separate classes of technological endeavours.

Another object is to safeguard operating personnel and patients from viral diseases by cross-infection, drawing out all airborne bio-entities away from laser surgery site to devitalize all viables by plasma and finally immobilize the thus annihilated non- viable bio-entities by high efficiency filtration before releasing the resultant sterile air into the operating room.

A further object is to enable the surgeon to perform the invasive surgical procedures independently by means of a combination hand-piece that co-axially configures an in-line laser probe and the laser plume aspirator without an assistant being required to track the movement of the laser probe and plume with a separate air suction aspirator.

Yet another object is to eliminate volatile organic compounds that are contained in the laser surgery emission.

Additional objects and advantages of the invention will become evident from the description which follows.

BRIEF DESCRPTION OF THE DRAWINGS

The attainment of the above objects is achieved through the physical embodiments depicted by the accompanying drawings.

Fig 1 illustrates an overall perspective of the main components of the apparatus inter-connected as an assemblage according to the invention.

Fig 2 is a cross-sectional view of a typical laser applicator for excising or ablating human tissue at surgery site, coaxially mounted within the aspirator hand-piece.

Fig 3 depicts a cross-section of the co-axially disposed laser applicator and plume aspirator as a single hand-piece such that both functions are in concert.

Fig 3a sketches separately configured laser applicator and plume aspirator in accordance with prior art. Fig 4 outlines the air-evacuating device comprising a cylindrical diaphragm and two interlocked valves.

Fig 5 shows in partial cross-section the plasma generator causing viral devitalization

Fig 6 gives a sectioned view of the HEPA cartridge that immobilizes non-viable particulates and adsorbs volatile organic compounds.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

To conveniently review the drawings, this explanatory text of the patent denotes each major component by an individual drawing figure identified by a single-digit numerical. The relevant elements which make up each component are denoted by double-digit numericals which carry the figure number as a prefix.

Peripherals like gas-lines, valves, power-packs, electro-electronic circuits, control panels, sensors, meters and monitors are not detailed as they are generic requirements of such apparatus and self-evident to those skilled in the art of the system operation.

Fig 1 represents an embodiment of this invention comprising a 1.5 mm 0 fibre optic cable transmitting a laser beam from its source hand-piece 2 for a surgeon to direct the laser energy to target surgery site. A 22 mm 0 nozzle slideably inserted into a coaxial aspirator hand-piece 3 leads to a 16 mm 0 flexible tube which connects to the intake valve of a solenoid actuated cylindrical diaphragm air pump 4 that directs the aspirated emission past the veπturi and plasma torch 5 onto the high efficiency filter cartridge 6 which captures the airborne particulates within its matrix which is impregnated with a catalytic agent such as titanium dioxide for adsorption of volatile organic compounds. For explicability components 2 and 3 are presented dimensionally in a scale larger than components 4, 5 and 6. Fig 4 outlines the air-evacuating device comprising a cylindrical diaphragm and two interlocked valves.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Fig 1 represents an embodiment of this invention comprising a 1.5 mm 0 fibre optic cable transmitting a laser beam from its source hand-piece 2 for a surgeon to direct the laser energy to target surgery site. A 22 mm 0 nozzle slideably inserted into a coaxial aspirator hand-piece 3 leads to a 16 mm 0 flexible tube which connects to the intake valve of a solenoid actuated cylindrical diaphragm air pump 4 that directs the aspirated emission past the venturi and plasma torch 5 onto the high efficiency filter cartridge β which captures the airborne particulates within its matrix which is impregnated with a catalytic agent such as titanium dioxide for adsorption of volatile organic compounds. For explicability components 2 and 3 are presented dimensionally in a scale larger than components 4, 5 and 6. Fig 2 and 3A illustrates a typical laser hand-piece attachable to a source of laser energy transmitted by a laser probe 21 having a proximal end 22 that a surgeon can direct to target site for ablative and electro-cauterization procedures. The applicator designated 23 is constructed as a quickly-attachable connector which coaxially fits snugly into the aspirator tube 24 that draws away the airborne plume debris via the 22 mm 0 nozzle thru a 16 mm 0 leader tube 35 as shown in Fig. 3. The Prior art method is illustrated by Fig 3a with the laser probe 21 and the aspirator hand-piece intake tube 24 manipulated separately and independently around the surgery site.

Referring to Fig 1, Fig 3 and 3A and 6 , a simplified example of the laser hand- piece 2 for ablative procedures comprises the fibre optic 21 focussed on the target surgery site and configured with the laser plume suction inlet nozzle 34 and suction tube

35 leading to a solenoid actuated diaphragm air pump 4 that forces the extracted air on to a conical plenum 61 that surrounds the plasma generator 5 . A power supply ( not shown ) produces an electric field in the gap between the anode and the cathode. The electric field generates excited atoms and secondary electrons that ionize the excited atoms, creating the strongly ionized plasma that devitalizes the viral contaminants picked up at the laser site by the suction inlet nozzle 36. The non-viable airborne viral contagions and other organic volatile compounds are pumped to a high efficiency filter cartridge 6.

Referring to Fig 1 and Fig 4 , the air evacuating device comprises a 80 mm 0 x 200 mm long silicone cylindrical diaphragm 41 pumping air by means of reciprocating press plates 42 that are mechanically fastened to the diaphragm and actuated by solenoids 43 . Two 50 mm 0 self-acting opposed air-intake and outlet valves 44 and 45, that operate synchronously with main diaphragm solenoids 43 to give a continuous airflow to the 30 mm 0 plasma generator 5 housed within the conical venturi 61 integrally connected with the cartridge filter 6. The silicone diaphragm inhibits particulate contaminants from adhering to its inner wall which can agglomerate for sporadic shedding. That's a common endogenous occurrence associated with centrifugal impellers and their scrolls, and no less by vacuum pumps and other means of creating vacuum as disclosed in prior art patents cited herein . Fig 5 details a partial cross-sectional view of the plasma generator comprising the height adjustable anode 51 fabricated from either thoriated tungsten or tantalum carbide 3 mm 0 rod, concentrically proximate to a 25 mm 0 silver cathode 52. The plasma generator has a primary annular pathway 53 for gases such as argon, helium, oxygen, freon and nitrogen, those have proved effective and any one of those can be introduced at 54 and in parallel at inlet 55 into a secondary annular pathway 56 egressing around the cathode 52 thus enlarging the field of ionizing electrons generated, in response to the discharge between cathode 52 and anode 51 . The electrodes are separated by an insulating member 57. The plasma discharge of about 250-350 Watts is sustained at relatively lower magnetic co-intensity, preferably in the range of 0.1 W/ cm² to 1 W / cm². The electron temperature is on the order of magnitude of 3 eV and the driving frequency is typically about 2.45 MHz₁ while for the prohibitively costly RF systems it is typically 13.66 MHz. Frequency of 2.45 MHz has been found just as effective for dissociating the molecular cell-contained moisture into atomic hydrogen and oxygen, essential for microbial devitalization . To achieve LOG 6 viral lethality, relatively low power densities in the range of 0.0125 - 0.025 W / cm³ are adequate. The anode 51 has an adjustable means to maintain its axial position relative to the cathode micrometrically by a threaded knob, whereby a density of about 10¹³ electrons per cubic centimeter uniformly distributed within a zone of approximately 20 cubic centimeter is generated to devitalize organisms.

Different factors contribute to the devitalizing effect : a) The pulsating fields coupled through the plasma to the organisms set up disruptive currents which alter the DNA molecules to an extent sufficient to prevent reproduction. In plasmas and cobalt 60 gammas, complex resonant current conditions have been observed in effecting a complete kill. Although circulating electric currents are believed to be a major factor in disrupting the DNA molecule, more complex effects also take place, including electron spin resonance and multiple nuclear magnetic resonance. Both modify the characteristics of the organism. All these effects are believed to be caused, at least to some extent, by response of the organisms to all pulsating fields, electric, magnetic or electromagnetic. Of course, at an appropriate frequency or combination of frequencies. b) Charged particles of the plasma penetrate the microorganisms upon striking a cell, give up energy, which breaks bonds within the DNA molecules. If, for example, the phosphate-sugar bond is broken, reproduction is inhibited. Within plasma fields the effectiveness of this aspect of the process depends on the relation between the mean- free path of the particles i.e. the distance they travel before striking an organism or another particle. Preferably, the mean-free path should be greater than 5 or even 10 organism diameters. The significance of this assumption is that if the CFU ( Colony Forming Units ) population is large, most of the charged particles will hit targets when they have traveled a distance which is short with respect to the organism size.

c) A molecular reaction between the plasma constituents including hydrogen, oxygen and ozone dissociated from the cell-contained moisture destroys the organism. The energy of the photons resulting from the excited condition of the plasma speeds up the chemical reaction so that even oxygen or nitrogen from the atmosphere are effective steriiants. It is safe to estimate that approximately 50 % of the energy of the charged particles is dissipated in penetrating the cell while the other 50 % is utilized in destroying the potential of the organism to reproduce.

Fig 6 shows the physical construction of the virus-tight high efficiency particulate capture and volatile organic compounds adsorption cartridge 6 which is about 150 mm 0 and 200 mm in height. The cartridge can immobilize non-viable bio-entities within the depth of the pleated matrix 64. The conical reaction venturi 61 interconnects the plasma generator 5 mounted on a flange 62 which is mounted integrally with the filter cartridge 6. Within the venturi the laser plume exhaust comes in intimate contact with numerous excited atomic and molecular species created by the plasma discharge. The interaction of those plasma species with the laser plume extract, consisting of vaporized tissue accomplishes the devitalization and inhibits viral reproduction.

The incident face of the pleated microfiberglass or porous polytetrafluroethylene media is impregnated with catalytic adsorbents such as, but not exclusively, titanium dioxide to eliminate volatile organic compounds within the laser surgery plume extract. The exhausted emission fully satisfies current environmental and personnel safety concerns, the products of the plasma being almost entirely water vapor, carbon dioxide and non-toxic gases normally found in the atmosphere. That treated air exits the perforated cage 65 after 99.999 % retention within the cartridge matrix 64 and the nonviable benign air is released to the surgery room. Over time that can lead to excessive clogging of the cartridge and that is indicated by a piezoelectric pressure sensor ( not shown ) that alerts and signals the need for a replacement. The replacement cartridge can be readily press fitted and sealed by means of double elastomeric O rings 63 into the filter retaining register 66.

For ergonomic placement by the operating personnel, the entire apparatus can be mounted as on a height adjustable tripod 67.

Although the proceeding description contains many specificities, those should not be construed as limiting the scope of the invention, but as merely being illustrative of one preferred embodiment of the invention.

ADVANTAGES OF THE PATENT

The corollary to the objects of this patent is to overcome the inadequacies of prior- art methodologies. All the laser patents listed in the citation conceptually and substantively overlook bio-risks to medical personnel who use their devices made in accordance to their specifications.

The major deficiency with prior art methodologies is that the laser plume evacuation contrivances require an attendant to hold the laser probe in close proximity to the laser aspirator being manipulated by the surgeon.

Another insufficiency with portable laser plume filtration systems is that they frequently take up precious floor space in a busy operating room, requiring doctors nurses to walk around them. If such a unit is placed off to the side of the room to keep it out of the way, then hoses must be connected to it, leading to the patient. The hoses then become an obstacle to contend with in the operating room . Since these units are self-contained, they include motorized vacuum pumps and tend to be quite noisy, detracting from the feeling of order that is desirable in an operating room during surgery. They recirculate the plume extract after filtration back into the operation room without eliminating the sub- 100 nanometer viral contagions that could cross-infect room occupants.

The centralized laser plume evacuation system operates through articulating arms in the medical procedure room, although it may also be accessed through wall or ceiling outlets or through a medical gas column and release the exhaust air carrying contagions to the atmosphere, possibly disseminating and exposing non-medical people to risk of viral infection.

The advantages of the present invention is that the above drawbacks have been overcome by an innovative method and apparatus.

While the present invention has been delineated by description of a preferred embodiment and the preferred embodiment has been described in considerable details, it is not contemplated to confine or in any way restrict the scope of the appended claims and their legal equivalence to such realization. Additional applications and adaptations will readily appear to those skilled in the art. The invention in its broader aspects is therefore not bound to the specific details that are representative of apparatus and method, and illustrative features shown and described herein. Accordingly, variations may be made from such details without departing from the utility or scope of the substantive inventive concept.

Claims

CLAIMSWhat is claimed is :

1. A self-contained apparatus for devitalizing viral contagions from a laser plume produced at surgical sites during medical procedures, such apparatus including : a combination hand-piece consisting of the optical fibre delivering the laser beam to the surgery site co-axially mounted in an aspirator that carries airborne emission from the plume to the plasma generator whereby performing both functions by one hand a diaphragm air pump whereby not to introduce exogenous particles into the air streams a reaction venturi whereby the laser surgery contaminants diffusing intimately and colliding with energized gas molecules comprising a variety of highly reactive products including metastable atoms, free radicals and ions a plasma generator achieving a density of about LOG 13 electrons per cubic centimeter to devitalize organisms a filter cartridge with penetration rating of 0.001 % for 0.1 micron particulates and to impregnate with multiple catalytic reagents from a group of titanium compounds

2. Apparatus as recited in Claim 1 wherein the devitalizing means is a plasma generator having : a central anode electrode fabricated from coated tungsten rod and a concentric cathode electrode fabricated from silver, coaxially mounted within a housing, centering an annular gap to create a plasma field to ionize the primary gas- stream that egress across the annular gap a primary plasma gas feed pathway concentrically surrounding the anode whereby precipitation of extract debris from surgical site onto the electrodes during excitation is inhibited by the flow of gas a secondary gas feed pathway for discharging gas axially and concentrically around the cathode, whereby the effective zone of plasma field is enlarged

3. Apparatus recited in Claim 1 and 2 wherein the plasma generator has : an anode where its axial position relative to the cathode is adjustable micro- metrically by means such as a threaded knob whereby a density of about 10¹³ electrons per cubic centimeter uniformly distributed within a zone of approximately 20 cubic centimeter is generated to devitalize organisms

4. Apparatus recited in Claim 1 and 2 comprising i) a laser probe is co-axially placed inside an aspirator hand-piece ii) an air evacuating diaphragm pump with two self-acting and opposed air valves iii) a reaction venturi iv) a filter with 0.001 % penetration against 0.1 micron particulate efficiency v) a filter with media impregnated with catalytic agents including titanium dioxide

5. Method for irreversibly devitalizing and immobilizing air-borne contagions generated during laser surgery : by suction of smoke plume caused by the laser surgical procedures by means of a diaphragm pump by diffusing them intimately to collide with neutral gas molecules and a variety of highly reactive products including metastable atoms, free radicals and ions, generated by a plasma field by accelerating mutagenesis by plasma excitation to inactivate all organisms including endotoxins to inhibit reproduction by photonic action of the plasma field that causes partial alteration of the disulphide rich protein coat of organisms to facilitate the diffusion of free radicals, atoms, or excited molecules inside the organisms core regions by coupling viral pathogens to the pulsating plasma fields and setting up disruptive currents which alter the DNA molecules to prevent their reproduction by charged particles of the plasma that penetrate the microorganisms and upon striking a cell, disrupt energy bonds within the DNA molecules and break the phosphate-sugar bond to inhibit reproduction by dissociating cell-structures into their constituents by energized plasma generator to annihilate all viable bio-entities from dermal, sub-dermal and muscle tissue ablated or excised by laser surgery by contacting vegetative biological entities containing cell-moisture with active ionic species that they break up the water molecules into their atomic elements whereby oxygen is available as a sterilant to devitalize spores by supplying a sterilant reactant gas-stream through the plasma field by additional annular gas-stream unidirectional and parallel to plasma field whereby the effective zone of microbial devitalization is enlarged by capturing airborne particulates, both biological and non-biological, during their passage through a pleated high efficiency filter matrix, such that the exit-air is free from viable non-mutagenic micro-organism.

6. A Method as recited in Claim 5 for evacuating , devitalizing and immobilizing air borne contagions from a laser surgery site : i) by a suction nozzle coaxially configured with the laser beam applicator ii) by a diaphragm air pump iii) by intimately contacting said contagions with plasma source generating an electronic density of about LOG 13 electrons per cubic centimeter in a zone of approximately 20 cubic centimeters iv by immobilizing the devitalized airborne contagions within the pleated media of a 0.001 % penetration against 0.1 micron particulates filter cartridge