WO2000027339A2

WO2000027339A2 - Apparatus and method for cleansing tissue

Info

Publication number: WO2000027339A2
Application number: PCT/IL1999/000599
Authority: WO
Inventors: Michael Tavger
Original assignee: Tav Tech Ltd.
Priority date: 1998-11-08
Filing date: 1999-11-07
Publication date: 2000-05-18
Also published as: IL126950A0; WO2000027339A3; AU1072800A

Abstract

Apparatus (11) for cleansing living tissue includes a source (41) of a sterile liquid which is maintained substantially at atmospheric pressure, a source of pressurized gas, a fluid delivery head(314) having a fluid outlet (354), a gas conduit (376) extending between a gas inlet (360) connected to the source of pressurized gas, a gas outlet (370) located in the fluid delivery head, a liquid conduit (386) extending between a liquid inlet arranged in fluid flow communication with the liquid source, and a liquid outlet located in the fluid delivery head and in fluid flow communication with the gas outlet, and a valve (372) mounted, and operatively associated with the gas conduit, permitting gas flow through the gas outlet.

Description

APPARATUS AND METHOD FOR CLEANSING TISSUE

FIELD OF THE INVENTION The present invention relates to the treatment of living tissue, in general, and to the cleansing of exposed living tissue, in particular.

BACKGROUND OF THE INVENTION

The cleansing of exposed in vivo tissue, such as of humans or animals during surgical procedures, requires the removal from the tissue of inorganic matter, such as fibers, dust, sand particles, and the like, and organic matter, such as pus, fats, and so on. Organic matter tends to be fastened to the tissue much more strongly than inorganic matter, and is thus more difficult to remove therefrom. Accordingly, while inorganic matter may be cleansed from the tissue by means of a liquid stream, it is often not possible to remove some of the organic matter from the tissue in this manner. More specifically, and most problematic, are those particles which are smaller than the thickness of the boundary layer of the fluid stream which is formed on the tissue; the boundary layer being characterized by having a fluid velocity which reduces sharply adjacent to the flow surface, and which is zero at the surface.

The smallest particles, which are located in the boundary layer, exhibit drag resistance of a magnitude that is sufficient for them to remain affixed to the surface and not to be swept away by the fluid stream, even if this stream has a very high velocity.

In an attempt to solve this problem, there have been developed a number of prior art devices which employ pulsed washing streams, such as described in U.S. Patents 4,350,158 entitled "Pulsating Spray Gas-Liquid Combining Member" and 4,982,730 entitled "Ultrasonic Wound Cleaning Method and Apparatus." These pulsed stream devices operate on the basis of providing a liquid stream with a reduced boundary layer thickness, in order to sweep away small particles. These devices, however, generally have complicated constructions, use very large quantities of liquid, and have been found to provide only a small improvement over non-pulsed devices. SUMMARY OF THE INVENTION

The present invention seeks to provide a method of and apparatus for cleansing living tissue, such as during surgical procedures on humans and animals, and which overcome disadvantages of known art

More specifically, it is sought to provide a cleansing method and apparatus which apply to the tissue surface a sterile liquid in a manner which is capable of removing even the smallest contaminant particles, thereby providing more effective cleansing of tissue than known in the art

Furthermore, the cleansing is performed while using relatively small amounts of liquid, thereby being not only more efficient and less wasteful than known methods, but also being more convenient and less messy to use than known methods

Yet further the cleansing may be performed utilizing sterile liquids contained in a steπle receptacle wherein the sterile liquid thus contained was filled under sterile conditions such that the sterility of the liquid thus contained and used for the cleansing is maintained at the high degree of sterility that is commonly found in operating facilities world-wide

The invention further utilizes vacuum suction to remove the liquid from the field of operation to facilitate the removal of contaminant particles from the cleansed site thus being more sanitary than known methods

The method of the invention is further characterized by having a therapeutic effect on the tissue being cleansed, thereby to accelerate its healing

There is thus provided, in accordance with a preferred embodiment of the invention, an apparatus for cleansing living tissue, which includes a source of a sterile liquid which is maintained substantially at atmospheric pressure, a source of pressurized gas, apparatus having a liquid entry port, and a gas entry port, a gas conduit extending between a gas inlet and a gas outlet, wherein the gas inlet is connected to the source of pressurized gas, and the gas conduit is connected to the source via a gas outlet port, and the gas outlet is connected to the gas entry port of the fluid delivery head, a liquid conduit extending between a liquid inlet arranged in fluid flow communication with the liquid source, and a liquid outlet, and wherein the liquid outlet is connected to the liquid entry port of the fluid delivery head and the liquid conduit is in fluid flow communication with the gas outlet port a valve device located between the entry ports and the fluid outlet for selectively permitting gas flow from the entry ports to the fluid outlet wherein the valve device is movable between first and second operative positions, and wherein, in the first position, the valve is operative to permit therethrough a high velocity, gas flow, at a sub-atmosphenc-pressure, thereby to expose the liquid outlet and thus the liquid source to a sub-atmospheric pressure so as to induce flow of the liquid into the fluid delivery head, and, when in second position, the valve is operative to substantially block the gas flow therethrough, such that the liquid is not induced to flow into the fluid delivery head, and wherein the fluid outlet comprises a gas-liquid combining member arranged to receive the gas and liquid flows and to combine them into a gas-liquid outflow which is operative to exit the apparatus through the fluid outlet in the form of a sterile liquid mist suspended in a high velocity gas stream

Additionally, in accordance with a preferred embodiment of the invention, the gas flow exits the valve device into the gas-liquid combining member at a pressure of a first magnitude, and the combining member is operative to cause a pressure drop in the gas flow therethrough such that the pressure of the gas-liquid outflow downstream of the fluid outlet, is of a second magnitude, wherein the first magnitude is at least twice the second magnitude, so as to cause a shock wave in the gas-liquid flow downstream of the fluid outlet and fragmentation of the liquid portion of the outflow into microscopic droplets, thereby to form a mist suspended in the gas portion of the outflow, and wherein the gas inlet of the gas conduit is constructed for connection to a pressurized oxygen source, and the outflow is an outflow of the sterile liquid mist suspended in a high velocity oxygen stream

Further in accordance with a preferred embodiment of the invention, the fluid outlet apparatus further includes an interior gas-liquid combining member arranged to provide an outflow of sterile liquid, and the gas-liquid combining member includes a rear portion configured to fit over the interior gas-liquid combining member and arranged to fit over the interior gas-liquid combining member so as to define a passageway therebetween for the gas flow, a front portion defining an opening, wherein the passageway is stepped so as to be increasingly constricted towards the front portion of the gas-liquid combining member, such that the gas flow passing through the passageway is accelerated to at least sonic velocity, and wherein the front portion widens towards the opening thereof such that the accelerated gas flow expands and thus undergoes a drop to a pressure which is sub-atmospheric, such that, when the gas-liquid combining member opening is brought to within a predetermined distance to tissue contaminated by pollutant particles, the particles are exposed to the sub-atmospheric pressure so as to be loosened thereby from the tissue

Further in accordance with a preferred embodiment of the invention, there is provided a suction conduit extending between a suction source end and a suction entry port end, wherein the suction source end is connected to a source of vacuum suction and the suction entry port end is connected to the suction entry port of the fluid delivery head, such that the fluid outlet has at least two chambers, of differing sizes, a larger chamber being constructed in such a manner such that it is configured to fit over the fluid delivery head, and a smaller chamber so configured as to contain a channel, following from and contiguous with the suction conduit entry port such that the gas-liquid outflow mist, having been discharged from the fluid outlet and now existing as a mixture of liquid and cleansed contaminant particles removed from tissue treated by and exposed to the mist traveling at supersonic speed, can be retrieved by this fluid delivery head and the mixture can be delivered via the suction conduit to a receptacle maintained for the purpose of gathering the mixture and retaining it so that it can be properly and sanitarily disposed of

Additionally in accordance with a preferred embodiment of the invention, there is provided a method of cleansing living tissue, which includes exposing a source of steπle liquid to a flow of pressurized gas, thereby to cause a drawn supply thereof into a fluid delivery head, supplying the pressurized gas to the fluid delivery head, combining the gas and liquid supplied to the fluid delivery head so as to provide a gas-liquid outflow in the form of a sterile liquid mist suspended in a high velocity gas stream, and exposing the living tissue to the gas-liquid outflow, thereby to loosen and remove therefrom contaminant particles, and exposing the gas-liquid outflow, now consisting of a mixture of liquid and cleansed contaminant particles, which are no longer attached to living tissue, to a suction force whereby the mixture is removed from the treatment site, so as to facilitate the complete removal of the contaminant particles from the living organism, such that they will not inadvertently be re-introduced into another area of the living organism being treated and such that the contaminant particles can be transferred to a receptacle maintained for the purpose of gathering the mixture and retaining it so that it can be properly and sanitarily disposed of

Further in accordance with a preferred embodiment of the invention, the step of supplying the pressurized gas includes supplying the gas at a pressure of a first magnitude, and the step of combining includes causing a pressure drop in the gas flow such that the pressure of the gas-liquid outflow, is of a second magnitude, wherein the first magnitude is at least twice the second magnitude, so as to cause a shock wave in the gas-liquid outflow and fragmentation of the liquid portion of the outflow into microscopic droplets, thereby to form a mist suspended in the gas portion of the outflow

Additionally in accordance with a preferred embodiment of the invention, and further comprising the steps, prior to the step of combining, of providing a gas outflow, causing an expansion of the gas outflow, thereby to cause a reduction in the pressure thereof to sub-atmospheric pressure, and providing a liquid outflow in conjunction with the expanded gas outflow

In accordance with a yet a further preferred embodiment of the invention, there is provided a method of cleansing and healing damaged living tissue, which includes exposing a source of sterile liquid to a flow of pressurized oxygen, thereby to cause a drawn supply thereof into a fluid delivery head, supplying the pressurized oxygen to the fluid delivery head, combining the oxygen and liquid supplied to the fluid delivery head so as to provide an oxygen-liquid outflow in the form of a sterile liquid mist suspended in a high velocity oxygen stream, and exposing the damaged tissue to the oxygen-liquid outflow thereby to remove therefrom contaminants and heal the damaged tissue

Further in accordance with a preferred embodiment of the invention, the step of supplying the pressurized oxygen comprises supplying the oxygen at a pressure of a first magnitude, and the step of combining includes causing a pressure drop in the oxygen flow such that the pressure of the oxygen-liquid outflow, is of a second magnitude, wherein the first magnitude is at least twice the second magnitude, so as to cause a shock wave in the oxygen-liquid outflow and fragmentation of the liquid portion of the outflow into microscopic droplets, thereby to form a mist suspended in the oxygen portion of the outflow

In accordance with yet a further preferred embodiment of the invention, the oxygen-liquid outflow has a near-sonic velocity

BRIEF DESCRIPTION OF THE DRAWINGS The present invention will be more easily understood and appreciated from the following detailed description, taken in conjunction with the drawings, in which

Fig 1 is a general view of the cleansing apparatus constructed and operative in accordance with a preferred embodiment of the present invention,

Fig 2 is a diagrammatic representation of a handpiece constructed in accordance with a preferred embodiment of the invention,

Fig 3 is a partial side view of the handpiece of Fig 2,

Fig 4A is an enlarged, cut-away view of the fluid delivery head,

Fig 4B is an enlarged, exploded view of the fluid delivery head,

Fig 5 is an enlarged, cut-away view of the gas-liquid mixing member of the fluid delivery head,

Fig 6 is an enlarged cross-sectional view of the circled area in Fig 5 indicated by arrow 6 therein,

Fig 7 is a cutaway view of the rear-portion and mid-section of the handpiece showing the valve assembly and the gas flow channel,

Fig 8A is an enlarged cross-sectional view of the valve seen in Fig 7, taken along line 8-8 therein, seen in an open position, and

Fig 8B is an enlarged cross-sectional view of the valve seen in Fig 7, taken along line 8-8 therein, seen in a closed position DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT Referring now to Figure 1 , the present invention provides apparatus, referenced generally 1 1 which employs a liquid and a gas as working fluids for cleansing living tissue, such as human or animal tissue during surgical procedures It will be appreciated from the following description that the present apparatus is characterized by being highly efficient for the removal of contaminant particles from living tissue including very small particles which cannot be removed by previously known methods The present invention further uses relatively small quantities of liquid, and thus, while serving to cleanse tissue and to prevent it from becoming dry during surgical procedures, it does not cause accumulations of large quantities of liquid in the operating area The use of vacuum suction pressure to remove excess spent liquid from the operating area further prevents this accumulation as well as providing for removal of contaminant particles Moreover, the use of oxygen, as a preferred gas, has therapeutic effects, which are well know, per se In Addition, the use of oxygen as a gas source renders the apparatus useful not only in the operating room, but in any hospital facility having a standard oxygen supply outlet A further purpose accomplished by the use of suction is to remove the contaminant particles thus cleansed and no longer attached to the living tissue, and to draw them away from the field of operation It will be appreciated by those familiar with the known art that this prevents the contaminant particles from being accidentally reintroduced to the living organism as well as gathering the contaminant particles for proper and sanitary disposal

Apparatus 11 includes a handpiece, reference generally 414, which includes a fluid delivery head 314, midsection 416, and rear portion 404 Rear portion 404, at end 378 thereof, is connected to sources of liquid and gas, respectively referenced 41 and 35, and is operative to combine these working fluids into a gas-liquid mist for cleansing living tissue, as described

Apparatus 11 includes a liquid conduit 56 having an inlet end 59 for accessing a source 41 of sterile liquid in a receptacle suitable for this purpose, such as the disposable polyethylene ones commonly used for containing intravenous solutions in hospital settings, well known and found in use in operating suites and hospital facilities world-wide This source 41 contains a supply of a sterile liquid, such as any suitable saline solution, for example, a 0 9% sodium chloride solution suitable for irrigation Liquid conduit 56 is connected to liquid source 41 via connector means 57 such as a standard hollow spike valve needle connector of the type prevalent in the art of current medical practice

Apparatus 11 also includes a gas conduit 34 which has an inlet end 36, which is preferably removably coupled via an oxygen plug 38 to an oxygen outlet 40, together defining a connection such as the "Ohmeda ™-Style Quick-Connect NPT" oxygen connection, well known and found in many hospitals in the United States and worldwide, and which has associated therewith a central, high pressure oxygen supply Preferably, the gas supply has a generally steady, non-pulsating pressure head, of approximately 2-3 atm

The handpiece 414 is also provided with a suction flow conduit 53, via which tissue contaminants and fluid are drawn away from living tissue and are passed to a container (not shown) for subsequent storage and disposal

With additional reference to Fig 2, within rear portion 404 of handpiece 414, liquid conduit 56 is attached, by a suitable coupling 363, to a liquid entry port 362 of liquid conduit 386 The gas conduit 34 is attached, by a suitable coupling 374, to a gas entry port 360 of gas conduit 376 Liquid and gas pass, from respective conduits 386 and 376, via respective outlets 354 and 370, to a gas-liquid combining member 276, whereat the gas and liquid are combined to produce a mist This mist is delivered at near sonic velocity, as described below, to a fluid outlet port 272 There is also provided a suction channel 256, whose purpose will be described below

With reference to Figs 4A and 4B, 5, and 6, fluid delivery head 314 is provided with a combining member 276, within which the gas and liquid are combined to form a fluid, as described below Combining member 276 includes a recessed portion 277, which is formed so as to cause a central conversion of the gas throughflow in head 314 towards the liquid emerging from the liquid conduit 386 Liquid exiting outlet 354 of conduit 386 flows through a needle-like liquid flow outlet bore 284 into gas-liquid combining member 276 Gas exiting outlet 370 enters an annular passageway 380 of gas-liquid combining member 276 via an entrance conduit 316 The gas flowing along passageway 380 accelerates from a sub-sonic velocity to a sonic velocity, and then further accelerates to supersonic velocity at the end 410 of passageway 380 As the gas flow emerges into a mixing chamber 306 of gas-liquid combining member 276, it expands rapidly The expansion wave thus generated undergoes a considerable pressure drop, to at least sub-atmospheric pressure, thereby also giving rise to a rarefaction zone 221 along the inner surface 222 of mixing chamber 306 Due to the velocity of the gas as it flows past opening 308 of bore 284, it creates a low pressure area in the mixing chamber 306 This low pressure area causes a small vacuum to be formed around the opening 308 of the liquid flow outlet bore 284 As a result, the liquid is drawn by the force of the vacuum suction through the liquid flow outlet bore 284 Thus, as long as this vacuum suction is present at the opening of the liquid flow outlet bore 284, liquid is constantly being supplied from the liquid source 41 to the bore 284 Since it is the gas flow which produces the suction which draws the liquid through the liquid conduit 56 and the liquid outlet 354, control of the gas flow alone is required in order to control the flow of both the gas and liquid As the liquid passes through outlet bore 284 into the supersonic gas stream, the sharp pressure drop experienced causes the liquid to fragment into microscopic droplets which are then swept into the gas stream, so as to form a combined gas-liquid mist stream consisting of a liquid mist suspended in a gas jet having a near sonic velocity

While there may be a minimal head loss during flow through the fluid delivery head 314, the fluid delivery head 314 is constructed so as to minimize such head loss, and so as to ensure that the fluid pressure remains in excess of 2 atm, until the point at which the fluid jet emerges through opening 312 of combining chamber 276 While the area of the fluid delivery head 314 is in equilibrium with the ambient atmosphere, with regard to pressure, the velocity of the fluid jet which emerges therefrom approximates the velocity of sound, namely, 330 m/s

When the fluid delivery head 314 is held close to tissue 224 (Fig 4A) contaminated with various pollutant particles, at a distance of, for example, 3-8 mm, these pollutant particles are exposed to a suction force, discussed below, which helps to loosen and to remove the particles from the tissue As the microscopic liquid droplets bombard the tissue and all contaminant particles thereon, they thus forcibly remove them from the tissue, thereby cleansing it The wetting of the contaminant particles in this way, namely, by microscopic droplets, causes a substantial increase in their aerodynamic resistance, such that the force of the bombardment is able to separate them from the tissue surface and to carry them away in the droplet stream The increase in the aerodynamic resistance of the particles is facilitated by the wetting by droplets, as well as by the absence of a liquid stream on the tissue surface with a stable boundary layer Accordingly, as none of the contaminant matter is protected by a stable boundary layer, it is all exposed to removal by the gas-liquid droplet stream Once the surface of the living tissue 224 has been wetted by the gas-liquid droplet stream, the liquid droplets, loosened contaminant particles, and mixtures thereof located upon the tissue 224 is readily removed As the delivery head 314 is in close proximity to the surface of the tissue 224, a vacuum force is exerted at the end 278 of a suction channel 256 This force draws the liquid droplets and/or contaminant particles back into a chamber 274 adjacent fluid outlet port 272, where the entire admixture is sucked into the vacuum suction channel 256 and removed to a receptacle at the other end of the vacuum suction line, where the admixture, containing the contaminant particles, can be gathered for subsequent proper and sanitary disposal

Referring now additionally to Figs 7, 8A, and 8B, handpiece 414 includes a valve assembly, referenced generally 372, which facilitates passage of liquid and gas, respectively, from liquid entry port 362 and gas entry port 360, into gas-liquid combining member 276 Valve assembly 372 includes a gas supply bore 342, which is connected to gas entry port 360 The front valve portion, generally referenced 394, communicates with gas conduit 376

Valve assembly 372 is provided with a thumb controlled head portion 271 , that extends via a narrow connecting element 336 through bore 342 Connecting element 336 includes a broadened portion 332 O-πng 330 rests on this broadened portion effectively preventing a throughflow of gas when the valve assembly 372 is in its closed position (Fig 8B)

Depression of head portion 271 inwards is operative to cause an inward, linear translation of connecting element 336, thereby lowering broadened portion 332, thereby allowing O-πng 330 to move away from bore 342, resulting in a partial opening of bore 342 and enabling a flow of gas through the valve assembly 372 Release of head portion 271 allows the head portion 271 to move outwardly, resulting in raising of broadened portion 332, thereby causing O-πng 330 to move into the path of bore 342, thus preventing the flow of gas therethrough

It will be appreciated by persons skilled in the art that the construction of the handpiece 414, as described above, is by way of example only, and other suitable types of connections and valves may be used, also in accordance with the spirit and scope of the invention It will be appreciated by persons skilled in the art that the scope of the present invention is not limited by what has been particularly shown and described above. Rather, the scope of the invention is limited solely by the claims which follow.

Claims

1 Apparatus for cleansing living tissue, which includes a source of a sterile liquid which is maintained substantially at atmospheric pressure, a source of pressurized gas, a fluid delivery head having a fluid outlet a gas conduit extending between a gas inlet connected to said source of pressurized gas and a gas outlet located in said fluid delivery head, a liquid conduit extending between a liquid inlet arranged in fluid flow communication with said liquid source and a liquid outlet located in said fluid delivery head and in fluid flow communication with said gas outlet a valve mounted and operatively associated with said gas conduit, permitting gas flow through said gas outlet, and wherein said valve is movable between first and second operative positions, wherein, in said first position, said valve is operative to permit therethrough a high velocity, sub-atmospheπc-pressured, gas flow, thereby to expose said liquid outlet and thus said liquid source to a sub-atmospheric pressure so as to induce flow of said liquid into said fluid delivery head, and, when in said second position, said valve is operative to substantially block said gas flow therethrough, such that said liquid is not induced to flow into said fluid delivery head, and wherein said fluid outlet comprises a gas-liquid combining member arranged to receive said gas and liquid flows and to combine them into a gas-liquid outflow which is operative to exit said apparatus through said fluid outlet in the form of a sterile liquid mist suspended in a high velocity gas stream

2 Apparatus according to claim 1 , wherein said gas flow exits said valve device into said gas-liquid combining member at a pressure of a first magnitude, and said combining member is operative to cause a pressure drop in the gas flow therethrough such that the pressure of the gas-liquid outflow, downstream of said fluid outlet, is of a second magnitude, wherein said first magnitude is at least twice said second magnitude, so as to cause a shock wave in the gas-liquid flow downstream of said fluid outlet and fragmentation of the liquid portion of said outflow into microscopic droplets, thereby to form a mist suspended in the gas portion of said outflow 3 Apparatus according to claim 2, wherein said gas-liquid outflow has a near-sonic velocity

4 Apparatus according to claim 1 , wherein said gas inlet of said gas conduit is constructed for connection to a pressurized oxygen source, and said outflow is an outflow of said sterile liquid mist suspended in a high velocity oxygen stream

5 Apparatus according to claim 2, wherein said fluid outlet device further includes an interior gas-liquid combining member arranged to provide an outflow of sterile liquid, and said gas-liquid combining member includes a rear portion configured to fit over said interior gas-liquid combining member and arranged to fit over said interior gas-liquid combining member so as to define a passageway therebetween for said gas flow, and a front portion defining an opening, wherein said passageway is stepped so as to be increasingly constricted towards said front portion of said gas-liquid combining member, such that said gas flow passing through said passageway is accelerated to at least sonic velocity, and wherein said front portion widens towards said opening thereof such that said accelerated gas flow expands and thus undergoes a drop to a pressure which is sub-atmospheric, such that, when said gas-liquid combining member opening is brought to within a predetermined distance to tissue contaminated by pollutant particles, the particles are exposed to said sub-atmospheric pressure so as to be loosened thereby from the tissue

6 Apparatus according to claim 1 and also including a suction conduit extending between a suction source end and a suction entry port end, wherein said suction source end is connected to a source of vacuum suction and said suction entry port end is connected to said suction entry port of said fluid delivery head, such that said fluid outlet has at least two chambers, of differing sizes, a larger chamber being constructed in such a manner such that it is configured to fit over said fluid delivery head, and a smaller chamber so configured as to contain a channel, following from and contiguous with said suction conduit entry port such that said gas-liquid outflow mist, having been discharged from said fluid outlet and now existing as a mixture of liquid and cleansed contaminant particles removed from tissue treated by and exposed to said mist traveling at supersonic speed, can be retrieved by this fluid delivery head and the mixture can be delivered via said suction conduit to a receptacle maintained for the purpose of gathering the mixture and retaining it so that it can be properly and sanitarily disposed of

7 A method of cleansing living tissue, which includes exposing a source of sterile liquid to a flow of pressuπzed gas thereby to cause a drawn supply thereof into a fluid delivery head, supplying the pressurized gas to the fluid delivery head, combining the gas and liquid supplied to the fluid delivery head so as to provide a gas-liquid outflow in the form of a sterile liquid mist suspended in a high velocity gas stream, exposing the living tissue to the gas-liquid outflow, thereby to loosen and remove therefrom contaminant particles, and exposing the gas-liquid outflow, now consisting of a mixture of liquid and cleansed contaminant particles, which are no longer attached to living tissue, to a suction force whereby the mixture is removed from the treatment site, so as to facilitate the complete removal of the contaminant particles from the living organism, such that they will not inadvertently be re-introduced into another area of the living organism being treated and such that the contaminant particles can be transferred to a receptacle maintained for the purpose of gathering the mixture and retaining it so that it can be properly and sanitarily disposed of

8 A method according to claim 7, wherein the step of supplying the pressurized gas includes supplying the gas at a pressure of a first magnitude, and the step of combining includes causing a pressure drop in the gas flow such that the pressure of the gas-liquid outflow, is of a second magnitude, wherein the first magnitude is at least twice the second magnitude, so as to cause a shock wave in the gas-liquid outflow and fragmentation of the liquid portion of the outflow into microscopic droplets, thereby to form a mist suspended in the gas portion of the outflow 9 A method according to claim 7, and further comprising the steps, prior to said step of combining, of providing a gas outflow, causing an expansion of the gas outflow, thereby to cause a reduction in the pressure thereof to sub-atmospheric pressure, and providing a liquid outflow in conjunction with the expanded gas outflow

10 A method according to either of claims 7 and 8 wherein the gas-liquid outflow has a near-sonic velocity

11 A method according to claim 7, wherein the pressurized gas is oxygen

12 A method of cleansing and healing damaged living tissue, which includes exposing a source of sterile liquid to a flow of pressurized oxygen, thereby to cause a drawn supply thereof into a fluid delivery head, supplying the pressurized oxygen to the fluid delivery head, combining the oxygen and liquid supplied to the fluid delivery head so as to provide an oxygen-liquid outflow in the form of a sterile liquid mist suspended in a high velocity oxygen stream, and exposing the damaged tissue to the oxygen-liquid outflow, thereby to remove therefrom contaminants and heal the damaged tissue

13 A method according to claim 12, wherein the step of supplying the pressurized oxygen comprises supplying the oxygen at a pressure of a first magnitude, and the step of combining includes causing a pressure drop in the oxygen flow such that the pressure of the oxygen-liquid outflow, is of a second magnitude, wherein the first magnitude is at least twice the second magnitude, so as to cause a shock wave in the oxygen-liquid outflow and fragmentation of the liquid portion of the outflow into microscopic droplets, thereby to form a mist suspended in the oxygen portion of the outflow

14 A method according to claim 12, wherein the oxygen-liquid outflow has a near-sonic velocity