US3593710A - Anesthetic apparatus - Google Patents
Anesthetic apparatus Download PDFInfo
- Publication number
- US3593710A US3593710A US793932*A US3593710DA US3593710A US 3593710 A US3593710 A US 3593710A US 3593710D A US3593710D A US 3593710DA US 3593710 A US3593710 A US 3593710A
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- United States
- Prior art keywords
- liquid
- anesthetic
- pressure
- vaporizer
- reservoir
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
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- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
- A61M16/00—Devices for influencing the respiratory system of patients by gas treatment, e.g. mouth-to-mouth respiration; Tracheal tubes
- A61M16/10—Preparation of respiratory gases or vapours
- A61M16/14—Preparation of respiratory gases or vapours by mixing different fluids, one of them being in a liquid phase
- A61M16/18—Vaporising devices for anaesthetic preparations
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
- A61M16/00—Devices for influencing the respiratory system of patients by gas treatment, e.g. mouth-to-mouth respiration; Tracheal tubes
- A61M16/08—Bellows; Connecting tubes ; Water traps; Patient circuits
- A61M16/0816—Joints or connectors
- A61M16/0833—T- or Y-type connectors, e.g. Y-piece
Definitions
- the reservoir is pressurized by a pressure line communicating with the reservoir at a region beneath the surface of the liquid, and a presure head is maintained independently of the level of the anesthetic material in the reservoirv
- the rate of flow of liquid through the conduit to the vaporizer chamber is controlled by regulating the pressure within the pressure line relative to the pressure within the pressure line relative to the pressure within the vaporizer chamber.
- the reservoir may be formed by an anesthetic containing bottle in sealing engagement with a support for the vaporizer to provide a compact assembly.
- the patient In the process of inducing a state of anesthesia in a patient, the patient is caused to inhale a mixture of a gas, such as oxygen, and an anesthetic vapor.
- a gas such as oxygen
- an anesthetic vapor a gas that is used, including ether, halothane (available under the trademark Fluothane), trichloroethylene, methoayflurane (available under the trademark Penthrane) and others.
- the desired concentration of any given anesthetic vapor in oxygen or other gas varies in dependence upon the particular patient, and may vary over a considerable range as anesthesia is first induced and subsequently maintained at a given stage.
- the range of concentration varies for different materials.
- the concentration of ether in some cases may be as high as 8 percent or more, while methoxyllurane may be administered at a concentration as low as 0.2 percent.
- Anesthetic materials are customarily available in the form of volatile liquids, and various methods have been used for evaporating the liquid anesthetic into a gas stream.
- Anesthetic apparatus known heretofore has been subject to one or more problems, including lack of accuracy in achieving the desired concentration, particularly over the wide range of concentrations necessary for use with different anesthetic materials, undue complexity, expense, and inconvenience.
- One common method is to bubble a stream of gas through a supply of liquid anesthetic to produce a highly concentrated mixture. Subsequently the mixture is diluted to achieve the desired concentration.
- One difficulty encountered with this method arises in accurately attaining the desired concentration since the rate of evaporation varies widely with temperature and pressure conditions.
- an object of the present invention to provide improved anesthetic apparatus for providing a gas and anesthetic mixture which can be controlled accurately over a wide range of concentrations.
- Another object is to provide improved anesthetic apparatus which is simple and convenient to operate.
- a further object is to provide improved apparatus for maintsining a, constant pressure head for evacuating anesthetic liquid from a container at a rate independent of a changing liquid level.
- Another object is to provide an apparatus in which the anesthetic concentration can be varied over a wide range and controlled with great accuracy.
- Another object of the invention is to provide improved anesthetic apparatus suitable for use with a wide variety of anesthetic materials and for use in both closed and open systems.
- anesthetic apparatus constructed in accordance with the invention may include a vaporizer chamber through which flows a stream of gas to which anesthetic vapor is to be added.
- An anesthetic material in the liquid state is introduced into the vaporizer chamber through a conduit from a closed cordance with an important feature of the invention, pressure within the reservoir forces the anesthetic through the conduit to the vaporizer chamber at a rate which is independent of the level of anesthetic in the reservoir. Accordingly, there is no requirement to maintain a constant level in the reservoir as in many prior art systems.
- the reservoir is pressurized by means of a pressure line communicating with the reservoir at a region beneath the surface of the anesthetic.
- the rate at which liquid flows into the vaporizer chamber is regulated accurately and conveniently by varying the pressure differential existing between the vaporizer chamber and the reservoir.
- the pressure differential may be controlled by regulating the pressure of the pressure line communicating with the reservoir, or by regulating the pressure within the vaporizer chamber, or both.
- the closed reservoir containing the liquid anesthetic comprises the bottle or container in which the liquid anesthetic is supplied.
- the bottle is held in sealing relation to a support member associated with the vaporizer, and both the pressure line and the liquid conduit extend into the bottle to a point beneath the surface of the liquid anesthetic contained in the bottle.
- the apparatus of the present invention may also include a novel arrangement for maintaining an even pressure differential between the vaporizer chamber and the regulator by controlling the reservoir pressure in accordance with minor fluctuations within the vaporizer chamber.
- a restricted bleed line may extend between the reservoir and the vaporizer chamber to prevent the buildup of excess pressure within the reservoir due to accelerated evaporation of the liquid anesthetic contained therein.
- a dual-purpose valve with a single control may be used to control the admission of pressurized gas to the regulator, and also to regulate the gas stream passing through the vaporizer chamber.
- FIG. I is a diagrammatic and elevational view, partly in section, of vaporizer apparatus constructed in accordance with the invention.
- FIG. 2 is a diagrammatic and elevational view, partly in section, of an alternative embodiment of the invention.
- FIG. 3 is a diagrammatic and elevational view, partly in section, of another alternative embodiment of the invention.
- FIG. 4 is a perspective view of a self-contained vaporizer unit including the components illustrated in FIG. 3;
- FIG. 5 is an exploded view of the unit of FIG. 4;
- FIG. 6 is an enlarged sectional view taken along the line 6-6 of FIG. 4;
- FIG. 7 is an elevational view of one side of the unit of FIG. 4.
- the unit I0 includes a vaporizer chamber designated as a whole by the reference numeral [2 and a closed reservoir generally designated as 14.
- a stream of gas to which an anesthetic vapor is to be added is conducted from a source of pressurized gas through a shutoff valve IS and through the vaporizer chamber 12 by means of an inlet conduit 16 and an outlet conduit 18 communicating with anesthetic mixture utilizing apparatus which may, for exarnple. be part of a closed or an open anesthetic system.
- anesthetic mixture utilizing apparatus which may, for exarnple. be part of a closed or an open anesthetic system.
- a gas such as oxygen
- a gas is passed through the vaporizer chamber 12 and mixed with a desired concentration of anesthetic vapor, and is forwarded via the outlet conduit 18 to patient breathing apparatus.
- the gaseous mixture is recycled through a closed circuit in which carbon dioxide is removed from the exhaled gas and additional oxygen combined with anesthetic vapor is added to replenish the flow.
- liquid anesthetic is forced to flow from the closed reservoir [4 through a liquid carrying conduit 20 to the vaporizer chamber I2 at a rate which is accurately controlled and is independent of the liquid level in the reservoir 14.
- the reservoir 14 is initially charged with a supply of anesthetic liquid and no effort is made to maintain a constant level within the reservoir [4 as the liquid anesthetic is used.
- the reservoir [4 is pressurized by means ofa pressure line 22 having an end 220 communicating with the reservoir preferably near the bottom so as to be beneath the surface ofliquid in the reservoir.
- the pressure head at the lower end 200 of the liquid conduit 20 is made up of two components.
- One component of the pressure head is produced by the pressure of the vapor or gas within the reservoir 14 above the surface of the liquid contained therein.
- the other pressure component results from the weight of the liquid within the reservoir 14 above the lower end 20a of the conduit 20.
- the liquid level does not remain constant and the component of the pressure head caused by the liquid decreases as the liquid level falls.
- this component of the pressure head acts on the submerged pressure line 22 as well as on the liquid conduit 20, the pressure of the gas contained within the reservoir l4 increases and compensates for the falling liquid level. Accordingly, the pressure head effective at the end 20a of the conduit 20 remains constant for a given pressure within the pressure line 22.
- the apparatus of the present invention is capable of providing accurately controlled anesthetic concentrations over a wide range.
- the conduit 20 is preferably of capillary size and may include a segment having an inner diameter in the neighborhood of 0.007 inch.
- the flow of liquid anesthetic through the conduit 20 is governed by the rules of laminar flow, in accordance with which the flow through the conduit 20 is proportional to the pressure differential existing between the lower end 20a of the conduit and an upper end 20b disposed within the vaporizer chamber 12. Since the pressure at the lower end 200 of the conduit 20 is determined by the pressure within the pressure line 22, the rate of flow of liquid anesthetic into the vaporizing chamber I2 is propor tional to the pressure differential existing between the pressure line 22 and the interior of the vaporizer chamber 12.
- the rate of flow of liquid anesthetic through the conduit 20, and thus the percentage concentration of anesthetic vapor in the stream of gas is accurately controlled over a broad range by controlling the pressure within the reservoir 14 relative to the pressure within the vaporizer 12.
- this is accomplished by controlling the pressure existing within the pressure line 22 by means of a pressure line regulator generally designated as 24, and controlling the pressure within the vaporizer chamber 12 by means of a back pressure regulator generally designated as 26.
- the pressure line 22 communicates with the outlet ofa pressure regulated valve 28, the inlet of which is connected to a source of pressurized gas by way of a shutoff valve 30. If desired a single source may be used both for the gas stream entering the inlet conduit to and for supplying the regulator 24, although separate sources are indicated in FIG. 1.
- the pressure regulator 24 may be of any suitable type, and as illustrated includes a diaphragm 32 acted upon by the pressure within the pressure line 22 and coupled to the valve 28 by means of a linkage 34 for operating the valve to maintain a constant pressure within the pressure line 22.
- the pressure acting upon the diaphragm 32 is opposed by the force applied by a spring 36, and preferably the spring tension is adjustable by means of a handle 38 with which the constant pressure level to be maintained within the pressure line 22 may be varied.
- the back pressure regulator 26 may be of any desired type, and is illustrated as being similar in many respects to the pressure line regulator 24.
- the gaseous mixture flowing from the vaporizer chamber I2 passes via the outlet conduit I8 to the inlet of a pressure regulated valve 40, the outlet of which is connected to the anesthetic mixture utilizing apparatus.
- the valve 40 is controlled by means ofa linkage 42 and diaphragm 44 to maintain the pressure at the inlet side of the valve 40, and thus the pressure within the vaporizer chamber 12, at a constant level.
- the pressure within the vaporizer chamber I2 is adjusted to a desired level by means of a handle 46 controlling the tension of a spring 48 acting on the diaphragm 44.
- the concentration of the anesthetic in the gas stream can conveniently and accurately be adjusted by means of the handles 38 and 46 of the pressure line regulator and the back pressure regulator. It is possible with the apparatus of the present invention to regulate the pressure differential and thus the flow rate with either one of the regulators 24 and 26, the other being omitted or combined with other equipment.
- one of the regulators 24 and 26 may be permanently set or factory adjusted at a selected level and the other may be adjusted by the anesthesiologist. If desired, of course, both of the regulators may be used. For example, one of the regulators may be set at a selected level to give a certain range of flow rates, and the other used for finer adjustments within the selected range.
- a pair of pressure responsive indicators 50 and 52 are connected respectively to the pressure line 22 and the outlet conduit l8 communicating with the interior of the vaporizer chamber 12.
- the readings of the indicators 50 and 52 indicate the pressure differential existing between the pressure line 22 and the vaporizer chamber 12, and thus the anesthetic concentration may be computed from this pressure differential.
- the indicators 50 and 52 may be provided with scales (not shown) calibrated in terms of anesthetic concentration.
- a pressure equalizing line 53 extends from the interior of the vaporizer chamber 12 to the dome portion of the pressure line regulator 24. Pressure variations existing within the vaporizer chamber l2 are communicated via the equalizing line 53 to the reverse or dome side of the diaphragm 32 automatically to control the valve 28 for maintaining a constant pressure differential between the vaporizer chamber and the reservoir.
- a problem may arise when the reservoir 14 is exposed to light or temperature variations. Under some conditions it is possible for the liquid within the reservoir 14 to evaporate at an accelerated rate and for the vapor pressure within the reservoir 14 to increase to an undesirable level. Rather than controlling the external conditions affecting the rate of evaporation, it may be preferable to provide a restricted bleed line 54 extending from the upper portion of the closed reservoir 14 to the interior of the vaporizer chamber 12. This line has a very small interior diameter, and serves very gradually to vent any excess pressures that may exist within the reservoir l4 to the lower pressure region within the vaporizer chamber 12. The line is small in size, and the limited flow of gas therethrough may readily be compensated for through calibration of the system.
- the chamber includes a cylindrical wall member 56 defining an interior chamber and preferably fonned of transparent material such as glass in order to permit viewing of the flow of anesthetic liquid from the conduit 20.
- the upper end b of the conduit 20 is provided with a drip guide 58 for causing the liquid to form droplets rather than running down the outer surface of the conduit 20 and/or into the line 54.
- the upper and lower ends of the cylindrical wall 56 are closed by body members 60 and 62.
- the upper body member 60 includes a pair of passages I80 and 53a communicating respectively with the outlet conduit 18 and the pressure equalizing line 53, and communicating with the interior of the vaporizer chamber [2.
- the lower body member 62 includes a passageway 16a communicating with the iniet conduit l6 and with the interior of the vaporizer chamber 12.
- the vaporizer chamber I2 is divided into two regions by means of a porous metal diffusion plate or baffle 64 supported within the lower body section 62.
- the stream of gas entering through the inlet conduit 16 passes through the diffusion plate 64 to reach the outlet conduit 18.
- Liquid anesthetic emerging from the conduit 20 falls from the drip guide 58 onto the plate 64 and is completely evaporated into the stream of gas moving through the plate 64.
- the lower body member 62 supports a sealing member 68 having a lower surface against which the neck of the bottle 66 abuts.
- the bottle 66 is held in sealing engagement with the sealing block 68 by means of a yoke 70 pivotally supported by the lower body member 62 and a clamping bolt 72 engaging the bottom of the bottle 66. Since the pressure line 22 and the conduit 20 extend downwardly through the lower surface of the sealing block 68. the unit I0 is assembled for operation merely by positioning the bottle 66 and clamping it in place.
- the apparatus of the present invention may be used with a high degree of accuracy over a wide range of anesthetic vapor concentration levels. Accordingly, the apparatus is well suited for use with a wide variety of different anesthetic materials which may require concentrations falling in widely varying ranges. However, if for precautionary reasons it is desired to restrict the use of the unit 10 to one particular anesthetic at one given time a suitable indexing means (not shown) may be provided on the sealing member 68 so that the unit can accept only one particular type of bottle associated with the one selected anesthetic material.
- Gas entering the vaporizer chamber 12 through the conduit 16 flows through the plate 64 and is mixed with evaporating anesthetic.
- the gaseous anesthetic mixture then flows through the outlet conduit 18 and through the back pressure regulator 26 to the utilizing apparatus.
- the back pressure regulator maintains a selected pressure level within the vaporizer chamber 12. As the liquid level drops in the reservoir 14, the pressure differential between the ends 20a and 20b of the conduit 20, as determined by the regulators 24 and 26, does not vary and the rate of flow of anesthetic remains constant.
- the shutoff valve 30 is closed, and the pressure within the reservoir 14 drops quickly due to provision of the bleed line 54 to stop the flow of liquid through the conduit 20. Since the reservoir 14 is located below the chamber 12, there is no liquid flow in the absence of pressure within the reservoir. in addition, when the bottle 66 is removed the conduit 22 is rapidly purged of liquid by the force of gravity.
- the liquid conduit 20 included a capillary size segment one-half inch in length and 0.0075 inch in diameter.
- the regulator 24 was adjusted so that the pressure within the line 22 was the equivalent of 24 inches of water.
- An oxygen gas stream was passed through the vaporizer at a rate of 1,000 cubic centimeters per minute.
- the reservoir 14 was charged with a supply of liquid ether, and the regulator 26 was adjusted to maintain the interior of the vaporizer at a pressure equivalent to 15.2 inches of water.
- Liquid ether flowed into the vaporizer at a rate equivalent to 66 cubic centimeters of vapor per minute and was evaporated into the gas stream to produce an anesthetic mixture of 6.6 percent ether vapor in oxygen.
- the unit was also capable of operation with other anesthetics and at other concentrations.
- the unit was also capable of operation with other anesthetics and at other concentrations.
- the unit was also capable of operation with other anesthetics and at other concentrations.
- reservoir 14 was charged with a supply of liquid halothane and the regulator 26 was adjusted to maintain the interior of the vaporizer 12 at a pressure equivalent to l 1.8 inches of water, while the other variables remained the same as in the previous example.
- Liquid halothane flowed into the vaporizer at a rate equivalent to 28 cubic centimeters per minute of vapor, and an anesthetic mixture of 2.8 percent of halothane vapor in oxygen was produced as the liquid evaporated into the gas stream.
- an anesthetic vaporizing unit generally designated as 80 and comprising an alternative embodiment of the present invention.
- the unit 80 includes a vaporizer chamber designated as a whole as 82 together with a closed reservoir generally designated as 84.
- a stream oigas to which an anesthetic vapor is to be added is conducted from a source of pressurized gas, through a shutoff valve 86 and through a conduit 88 to the vaporizer chamber 82 where an anesthetic vapor is added to the gas stream.
- the anesthetic and gas mixture leaves the vaporizer chamber 82 through a conduit 90 and is supplied to suitable anesthetic mixture utilizing apparatus.
- liquid anesthetic is forced to flow from the closed reservoir 84 into a submerged lower end 920 of a liquid conduit 92 and to the vaporizer chamber 82 at a rate of flow which is independent of the level of liquid in the reservoir 84.
- the reservoir 84 is pressurized by means of a pressure line 94 having a lower end 940 communicating with the reservoir at a region beneath the surface of the anesthetic liquid in normal operation.
- valve 96 includes an operat ing handle 98 with which the valve setting may be varied between several different settings thereby to vary the resistance to the flow of liquid from the reservoir 84 to the vaporizer 82.
- the valve 96 may be of any known type such as a variable orifice valve, or a valve of the type in which movement of the operating handle serves to vary the effective length of a capillary size passageway.
- the rate of flow of anesthetic from the reservoir 84 to the vaporizer 82, and thus the concentration of the gas anesthetic mixture is controlled by regulating the pressure differential existing between the reservoir 84 and the vaporizer 82 and/or by operating the metering valve 96 to vary the resistance to flow between the reservoir 84 and the vaporizer 82.
- the unit 80 is illustrated as used with anesthetic mixture utilizing apparatus of a type which maintains the pressure within the vaporizer chamber 82 substantially constant, although a back pressure regulator similar to the regulator 26 of FIG. I could be used if desired.
- the pressure differential between the reservoir 84 and the vaporizer 82 is varied by controlling the pressure in the pressure line 94 with a pressure line regulator generally designated as I00 and including a pressure regulated valve I02 having its inlet connected through a conduit I04 to the shutoff valve 86, and having its outlet connected to the pressure line 94.
- the valve I02 is controlled by a linkage I06 operated by a diaphragm I08 acted upon by the pressure within the pressure line 94 in opposition to a spring III], the tension of which is adjustable by means ofa handle I12.
- the rate of flow of liquid anesthetic to the conduit 92 is proportional to the pressure differential existing between the reservoir 84 and the vaporizer 82
- the rate of flow may be adjusted by operation of the handle I12 to a setting which provides the desired constant pressure within the pressure line 94.
- a pressure responsive indicator [I4 communicates with the pressure line 94 to provide a pressure reading or, if desired, a direct reading of the pressure differential existing between the reservoir 84 and the vaporizer chamber 82.
- this chamber may be constructed in any suitable fashion and is illustrated as including a trans parent cylindrical wall I16 having its upper and lower ends closed by body members I18 and I20.
- the body members are provided with suitable passageways 88a, 90a and 92b communicating between the interior of the vaporizer chamber and the conduits 88, 90 and 92 respectively.
- a porous metal diffusion plate or baffle I22 divides the vaporizer chamber 82 into two regions.
- the stream of gas entering through the conduit 88 passes through the plate I22 and through the conduit 90 to the anesthetic mixture utilizing apparatus.
- Liquid anesthetic entering the vaporizer chamber 82 from the conduit 92 falls onto the plate 122 and is completely evaporated into the gas stream flowing through plate 122.
- the liquid reservoir 84 of the unit 80 may be of any desired construction and as illustrated includes a container I24 closed by means ofa sealing member 126 held against the container 124 by a suitable clamp or other means (not shown). It should be appreciated that if desired the unit 80 of FIG. 2, may in clude an arrangement such as illustrated in the unit 10 of FIG. I wherein the reservoir comprises the original container of the liquid anesthetic and wherein the reservoir and the vaporizer chamber are combined in a single unit. In addition, the unit 80 may be provided with a restricted bleed conduit and with a pressure equalizing line similar to the conduit 54 and line 53 ofthe unit illustrated in FIG. I.
- the shutoff valve 86 is opened so that a stream of gas flows through the vaporizer chamber 82 and to the anesthetic mixture utilizing apparatus.
- the reservoir 84 is charged with a supply of anesthetic liquid, and the metering valve 96 as well as the pressure line regulator I00 are adjusted to selected settings for producing the desired concentration of liquid anesthetic in the gas stream.
- the liquid anesthetic is evacuated from the reservoir 84 through the liquid conduit 92 and into the vaporizer chamber 82 where the liquid evaporates completely into the gas stream.
- the effective pressure head within the reservoir 84 causing the evacuation of the liquid remains constant as the liquid level falls due to the fact that the reservoir is pressurized by the pressure line 94 which terminates at a point beneath the surface of the liquid.
- FIGS. 3-7 there is illustrated a liquid anesthetic vaporizing unit designated as a whole by the reference numeral and comprising a further embodiment of the present invention.
- the unit in general includes a vaporizer chamber generally designated as 142 together with a liquid anesthetic reservoir generally designated as I44.
- a stream of gas to which an anesthetic vapor is to be added is conducted from a source of pressurized gas through a conventional shutoff valve I46 and through a conduit I48 and into the vaporizer chamber I42.
- a liquid anesthetic is vaporized and mixed with the stream of gas, and the mixture of gas and an anesthetic is conducted to an anesthetic mixture utilizing apparatus by way of a conduit 150.
- the unit I40 operates to supply a uniform anesthetic concentration regardless of the level ofliquid anesthetic in the reservoir 144. Furthermore the concentration is accurately controlled and is variable over a wide range.
- the unit is conveniently arranged in a compact package with all controls and connections readily accessible. Furthermore a singlemanual control serves to operate a novel dual-purpose valve to control both the admission of pressurized gas to the reservoir and to control the volume of gas flow into the vaporizer through conduit 148.
- the unit 140 shown schematically in FIG. 3 comprises a compact assembly including a housing 152 with the vaporizer chamber I42 and the liquid anesthetic reservoir 144 mounted in an accessible location on the exterior thereof.
- This construction has the advantage that much of the apparatus is safely enclosed within the housing I52, while the reservoir I44, chamber I42 and the necessary controls are readily accessible to an operator.
- the vaporizer chamber comprises a somewhat bell-shaped enclosure I54 preferably formed of glass or other transparent material.
- the enclosure I54 is held in position over a base member 156 by a threaded clamp ring 158.
- the interior of the vaporizer chamber enclosure 154 is sealed by a pair of sealing gaskets I60 and 162 held in compression by the clamp ring 158.
- the upper portion of the vaporizer enclosure 154 is communicated with the conduit 150 by means of a fitting 164 threadedly connected to an elbow 166.
- a pair of seals 168 and I70 are held in compression against the wall of the enclosure 154 by engagement between the fitting I64 and the elbow 166.
- the base member 156 In order to admit a stream of gas to the lower portion of the vaporizer chamber from the conduit I48, the base member 156 includes a passageway 148a extending from the lower surface of the base member I56 to the interior of the vaporizer chamber I42.
- a porous metal diffusion plate or baffle I72 extends across the vaporizer chamber 142 between the passageway 148a and the fitting 164 in order to accomplish the evaporation of liquid anesthetic into the flowing gas stream.
- the baffle 172 is held in place by means of a pressure ring 174 held in place by means of the seal 162.
- the reservoir 144 advantageously and conveniently comprises the original container or bottle in which the liquid anesthetic is supplied.
- this arrangement greatly simplifies handling and use of the anesthetic vaporizing unit.
- the bottle is readily inserted into place on the unit 140 by threading the neck of the bottle into an adapter member 176 which is in turn threaded into an extension 1560 of the base member 156.
- the lip of the bottle is sealed by engagement with a sealing block or member I78 supporting an O-ring 180.
- various adapter members 176 may be provided for mating with different types of bottles containing different anesthetic materials.
- the vaporizer unit is universally adaptable, and the adapter member I76 serves to prevent the use of an anesthetic material other than the material intended for use by the operator.
- the chamber 142 and the reservoir 144 are supported on the base member 156, a unitary, compact and easily handled subassembly is made possible.
- evacuation of the liquid anesthetic material contained within the reservoir I44 is ac complished by the introduction of pressurized gas into the vaporizer chamber at a level normally beneath the surface of the liquid. In this manner the rate of flow, and thus the concentration, is maintained independent of the level of liquid contained within the reservoir.
- the pressurized gas is introduced into the reservoir through a conduit I82, while liquid anesthetic material is discharged from the reservoir vaporized chamber through a liquid capillary conduit 184.
- the conduits I82 and 184 are part of a unitary assembly supported on the base member 156 and designated as a whole by the reference numeral I86.
- the pressurized gas conduit I82 communicates with a passageway 182a formed within the base member I56.
- the upper end of the conduit I82 is attached to the base member 156, while its lower end is attached to a fitting 188 having an outlet opening into the reservoir 144.
- the liquid conduit I84 extends through a passageway 184a in the base member I56 between the reservoir 144 and the vaporizer chamber 142.
- the liquid conduit 182 which is of small, capillary size, is preferably protected by a jacket member or tube 190 having its ends connected to the base member 156 and to the fitting 188. Fluid is admitted to the lower end I84a of liquid conduit 184 through a filter screen 192 held in place on fitting 188 by a threaded cap I94.
- ajacket or tube 196 is provided The lowermost end of jacket I96 is attached to a fitting I98 threaded into the base member 156 through the porous metal diffusion plate I72v The uppermost end of the jacket I96 supports a drip guide 200 for guiding liquid anesthetic material emerging from the upper end 184!) of the liquid conduit I84 outwardly of the jacket 196 so that it descends onto the diffusion plate 172.
- a bleed passage from the reservoir 144 to the vaporizer 142.
- gas can flow from the reservoir through a small hole 1900 in the jacket I and into the passage 184a in the base member 156. This gas is then vented into the vaporizer chamber through a small passage 202 in the fitting 198.
- the reservoir When pressurized gas is admitted to the reservoir I44 through the passageway 182a and the conduit 182, the reservoir becomes pressurized and liquid anesthetic material is discharged from the vaporizer through the filter screen I92 and the capillary conduit 184 into the vaporizer chamber I42 where it is deposited upon the diffusion plate or baffle I72.
- a stream of gas to which anesthetic gas is to be mixed enters the vaporizer chamber through the passageway I480 and passes through the porous plate or baffle 172. Liquid anesthetic material reaching the diffusion plate is evaporated into the gas stream, and the anesthetic and gas mixture is discharged from the vaporizer chamber 142 through the fitting 162, elbow I66 and conduit I50.
- the housing includes a laterally extending support arm 204 defining a recess 206 complementary in shape to the projection I56a of the base member I56. This recess is flanked by a pair ofextensions 204a and 20412 of the arm 204.
- the base member 156 is merely dropped into place on the arm 204.
- each passageway communicates with a quick release nipple 208 and 210 respectively.
- the nipples 208 and 2I0 are slidingly received within recesses 212 and 214 formed in the arm extensions 204a and 204i).
- the recesses 212 and 214 are communicated by way of passageways 218 and 220 (FIG. 6) respectively with the conduit I48 and a pressure line conduit 222 illustrated only in FIG. 3.
- the conduit 150 is connected to a slipfit connector 224 engageable with a nipple 226 (FIG. 5). Consequently, the entire vaporizer assembly can readily be attached and detached from the housing 152 at will.
- pressurized gas for supplying the pressure line 222 is obtained from a source of pressurized gas by way of the shutoff valve I46.
- a pressure regulator generally designated as 228 serves to regulate the pressure within the pressure line 222 and may if desired be of the construction of the regulator 24 illustrated in more detail in FIG. I.
- flow of pressurized gas through the pressure line 222 is controlled by a shutoff valve generally designated as 230.
- the volume of flow of gas through the conduit 148 may be regulated by means of throttling valve generally designated as 232.
- the shutoff valve 230 in the pressure line 222 and the throttling valve 232 in the conduit 148 are combined into a single-valve assembly operable by means of a single-manual control.
- An important advantage of this novel arrangement is that gas is admitted to the vaporizer chamber at the time the reservoir is pressurized so that the vaporizer cannot be flooded or subjected to excess liquid anesthetic.
- a single dual-purpose valve generally designated as 234 including a central bore 237 defining a valve seat 238 for the shutoff valve 230,
- the bore 237 receives an adjustable threaded plug 240 defining a seat 242 for the throttling valve 232.
- a valve member 244 is threaded into the opposite end of the bore 237 in order to control the opening and closing of both valves 230 and 232.
- the valve member 244 includes a first tapered valve surface 244a engageable with seat 238 and a second tapered valve surface
- An operating shaft 2440 of the valve body member 244 is adapted to be provided with an operating handle 246 (FIG. 7) for moving the valve surfaces 244a and 2442: into and out of engagement with the seals 238 and 242.
- the plug 240 is preferably adjusted so that when the valve 230 is fully closed, the valve 232 is closed as well.
- the pressure line shutoff valve 230 opens rapidly to a fully open position due to the relatively abrupt taper of surface 2444.
- the throttling valve 232 opens only gradually. Consequently, it is possible for the single-operating handle 246 to control the dual-purpose valve member for both the shutoff valve and the throttling valve functions.
- the rate of flow of anesthetic liquid through the liquid conduit 184, and thus the concentration of the anesthetic mixture provided by the unit 140 is controlled by controlling the pressure differential existing between opposite ends of the liquid conduit 184.
- the pressure regulator 228 controls the pressure of gas admitted to the reservoir 144 through the pressure line 222.
- a back premure regulator 248 controls the pressure existing within the conduit 150, and thus the pressure within the vaporizer chamber 142 at the uppermost end of the liquid conduit 184. If desired, the back pressure regulator 248 may be similar in construction to the regulator 26 illustrated in detail in FIG. 1.
- Control of the rate of flow of liquid anesthetic material through the liquid conduit 184 is achieved through adjustment of one or both of the pressure regulators 228 and 248.
- the back pressure regulator 248 is normally adjusted by the operator to vary the flow rate and thus the concentration, while the pressure line regulator 228 is nonnally preadjusted or factory adjusted at a given level.
- an operating knob 250 for the regulator 248 is positioned in an accessible position of the face of the housing 152.
- the regulator 228 may be located behind a removable plate 251 on a sidewall of the housing 152 (FIG. 7).
- a differential pressure gauge 252 is connected between the pressure line 222 and the conduit 150 FIG. 3) and gives a pressure reading propor tional to the rate of flow through the liquid conduit I84. Conveniently, this pressure gauge is located on the housing 152 above the adjustment knob 250. It should be understood that 244b engageable with seat 242.
- a flow indicator could be included in the system, for example in the conduit 148 or the conduit 150, in accordance with known practice.
- conduit I48 and the regulator 228 Convenient attachment of the conduit I48 and the regulator 228 to a conduit 254 (FIG. 3) leading to a source of pressurized gas by way of the conventional shutoff valve 146 is made possible by a quick release tube fitting 256 located on the face of the housing I52 (FIG. 7).
- a quick release tube fitting 256 located on the face of the housing I52 (FIG. 7).
- the use of a single source of gas assures that the vaporizer receives a gas flow whenever the reservoir is pressurized.
- Connection of the back pressure regulator 248 by way of a conduit 258 to a anesthetic mixture utilizing apparatus is made possible by another tube fitting 260 on the housing I52.
- liquid anesthetic vaporizing unit The operation of the liquid anesthetic vaporizing unit will be apparent to those skilled in the art from the preceding detailed description. Reviewing the operation, it is assumed initially that the shutoff valve 146, the valve 230 and the valve 232 are all in their closed positions and the unit 140 is not in operation. To prepare the unit for operation, a bottle of a selected liquid anesthetic is attached to the base member 156 by means of a mating adapter 176. The vaporizer unit is connected to the housing 152 of the unit 140 either before of after the bottle of anesthetic is attached to the base member 156.
- the shutoff valve I46 is opened to admit pressurized gas to the unit 140 through the fitting 256 on the face of housing 152.
- the operating handle 246 for the valves 230 and 232 is then opened in order to fully open the shutoff valve 230 and to open the throttling valve 232 in order that the flow through the conduit 148 is at the desired rate.
- the back pressure regulator 248 is adjusted through a manipulation of knob 250 until the reading of gauge 252 indicates that the desired rate of flow of liquid anesthetic is established.
- Pressurized gas then flows from conduit 148 through the vaporizer chamber and by way of conduit 150 through the back pressure regulator 248 to the anesthetic mixture utilizing apparatus. Simultaneously, pressure admitted to the reservoir by way of conduit 222 pressurizes the reservoir and forces liquid anesthetic material through the liquid conduit I84 into the reservoir chamber where it is evaporated into the gas stream.
- anesthetic liquids such as ether, halothane, trichloroethylene and methoxyflurane could be mixed with oxygen at extremely accurate and widely variable concentration levels. It was found that the rate of flow of the anesthetic material into the vaporizer chamber could be accurately controlled, independently of the liquid level, by control of the pressure drop between the pressure line 222 and the conduit 150 as shown by the reading of the pressure gauge 252. This pressure drop could readily be controlled by adjustment of the regulator 248.
- F, F F, and F represent the flow of ether, halothane, trichloroethylene and methoxyflurane respectively, expressed in cubic centimeters per minute of the vapor, while 81 represents the pressure drop between the pressure line conduit 222 and the outlet conduit 150 expressed in inches of water. Since the flow through the conduit 184 is governed by the rules of laminar flow, the flow is a substantially linear function of the pressure drop within the operative range of pressures which may be from about l5 to about 80 or more inches of water.
- the concentration of the anesthetic and gas mixture can be accurately and conveniently controlled through a wide range of concentrations simply by adjustment of the pressure drop and the rate of gas flow through the vaporizer chamber, For example, if ether is used and the valve 232 is adjusted to permit oxygen to flow through the vaporizer chamber 142 at a rate of about 2,000 cubic centimeters per minute, while the pressure drop is adjusted to about 45 inches of water, concentration of about 8 percent of ether in oxygen is obtained. In contrast, if methoxyflurane is used and oxygen is conducted through the vaporizer chamber at a rate of about 6,000 cubic centimeters per minute, while the pressure drop is maintained at about inches of watena concentration of about 0.34 percent is obtained.
- Anesthetic vaporizer for adding anesthetic vapor to a stream of gas in order to provide an anesthetizing gaseous mixture, said vaporizer comprising:
- said passageway defining means including a vaporizer chamber through which the stream of gas flows;
- a closed reservoir adapted to be charged with a supply of anesthetic in the liquid state
- conduit having one end disposed within said reservoir and having another end communicating with said vaporizer chamber, said one end terminating at a point below the normal operating level of the liquid;
- said pressurizing means including a pressure line for introducing a pressurized gas into said reservoir and communicating with said reservoir at a region beneath the surface of the liquid anesthetic contained therein.
- the vaporizer of claim I further comprising adjustable means for controlling the pressure differential between said region and the interior of said vaporizer chamber, thereby to control the rate of flow of liquid through said conduit.
- said adjustable means comprising a pressure regulator connected to said pressure line for regulating the pressure at said region.
- said adjustable means comprising a pressure regulator communicating with said passageway defining means for regulating the pressure within said vaporizer chamber.
- said adjustable means further comprising an additional pressure regulator communicating with said passageway defining means for regulating the pressure within said vaporizer chamber.
- the vaporizer of claim I further comprising a metering valve in said conduit between said vaporizer and said closed reservoir for varying the resistance to the flow of liquid anesthetic through said conduit.
- the vaporizer of claim 6 further comprising adjustable means for controlling the pressure differential between said region and the interior of said vaporizer chamber.
- a liquid anesthetic vaporizing unit for adding anesthetic material to a stream of gas comprising a container adapted to contain a supply of liquid anesthetic material, a vaporizer including wall means defining an evaporation chamber, a first passage in said wall means for conducting the stream of gas into said chamber, a second passage in said wall means for conducting the stream of gas from said chamber, sealing means supported by said wall means, a conduit having a first portion extending outwardly from said wall means and having a second portion communicating with said chamber for introducing anesthetic material into said chamber said first portion terminating within said chamber at a point below the normal operating level of the liquid, means for holding said container against said sealing means with the first portion of said conduit extending into said container, a second conduit ex tending outwardly from said sealing means and received within said container terminating at a point below the normal operating level of the liquid, and means for introducing pres surized gas into said second conduit for pressurizing the region bounded by said container and said sealing means.
- the unit of claim 8 further comprising means defining a bleed passageway extending from said container to said chamber for venting excess pressures from said container into said chamber.
- Anesthetic vaporizer for adding anesthetic vapor to a stream of gas in order to provide an anesthetizing gaseous mixture, said vaporizer comprising:
- a reservoir for holding a supply ofliquid anesthetic material
- a conduit extending from said reservoir to said vaporizer chamber for conducting liquid anesthetic to said vaporizer chamber for evaporation into the stream of gas one end of said conduit terminating below the normal operating level of the liquid;
- a pressure line communicating with said reservoir for pressurizing said reservoir thereby to force liquid anesthetic to flow through said conduit one end of said pressure line terminating within said reservoir at a point below the normal operating level ofthe liquid;
- pressure regulating means connected to said outlet passageway for controlling the pressure within said vaporizer chamber, thereby to control the rate of flow of liquid anesthetic through said conduit.
- the anesthetic vaporizer of claim 10 further comprising an additional pressure regulator connected to said pressure line for controlling the pressure within said pressure line.
- the anesthetic vaporizer of claim ll further comprising a pressure equalizing line extending between said vaporizer chamber and said additional pressure regulator for compensating for pressure variations within said vaporizer chamber.
- a method of producing a mixture of a gas and the vapor ofa liquid anesthetic material from a reservoir comprising the steps of:
- the method of claim 13 further comprising controlling the pressure difference between the pressure of said point and the pressure at said vaporizing chamber in order to meter the flow through said conduit.
- step of controlling the pressure difference includes the steps of regulating the pressure of said pressurized gas, and regulating the pressure of said stream of gas.
- Apparatus for producing a mixture of anesthetic and gas comprising a reservoir for a supply of anesthetic in liquid form, a vaporizer chamber, first conduit means for passing a stream of gas through said chamber, a liquid passageway for discharging liquid anesthetic from said reservoir into said chamber for evaporation into said stream of gen one end of said passageway terminating at a point below the normal 17.
- said valve assembly including a valve bore, first and second seats in said bore, and a single valve member movable in said bore having first and second valve seating surfaces engageable with said first and second seats to close said first and second valves.
- first and second valve seating surfaces being constructed and arranged with respect to said first and second seats so that said first valve is a shutoff valve and said second valve is a throttling valve
Landscapes
- Health & Medical Sciences (AREA)
- Anesthesiology (AREA)
- Heart & Thoracic Surgery (AREA)
- Pulmonology (AREA)
- Engineering & Computer Science (AREA)
- Biomedical Technology (AREA)
- Emergency Medicine (AREA)
- Hematology (AREA)
- Life Sciences & Earth Sciences (AREA)
- Animal Behavior & Ethology (AREA)
- General Health & Medical Sciences (AREA)
- Public Health (AREA)
- Veterinary Medicine (AREA)
- Filling Or Discharging Of Gas Storage Vessels (AREA)
- Feeding, Discharge, Calcimining, Fusing, And Gas-Generation Devices (AREA)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US79393269A | 1969-01-27 | 1969-01-27 |
Publications (1)
Publication Number | Publication Date |
---|---|
US3593710A true US3593710A (en) | 1971-07-20 |
Family
ID=25161198
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US793932*A Expired - Lifetime US3593710A (en) | 1969-01-27 | 1969-01-27 | Anesthetic apparatus |
Country Status (6)
Country | Link |
---|---|
US (1) | US3593710A (de) |
DE (1) | DE2003036A1 (de) |
FR (1) | FR2029491A1 (de) |
GB (1) | GB1299311A (de) |
NO (1) | NO123443B (de) |
SE (1) | SE358297B (de) |
Cited By (16)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3809080A (en) * | 1970-06-24 | 1974-05-07 | Deaton Medical Co | Sterile liquid entraining system |
DE3315943A1 (de) * | 1983-05-02 | 1984-11-08 | Drägerwerk AG, 2400 Lübeck | Narkosemittelverdunster mit einem der verdunsterkammer parallelgeschalteten bypass mit einer ueberwachungseinrichtung |
US5068993A (en) * | 1990-10-05 | 1991-12-03 | Millar John G | Method and apparatus for anesthetizing caught fish |
US5535737A (en) * | 1993-11-16 | 1996-07-16 | The Boc Group, Inc. | Anesthetic vaporizers |
US5918595A (en) * | 1995-12-21 | 1999-07-06 | Siemens-Elema Ab | Method for vaporizing an anesthetic liquid and vaporizer operating according to the method |
US6298845B1 (en) * | 1998-09-02 | 2001-10-09 | Siemens Elema Ab | Vaporizer |
US6318361B1 (en) * | 1998-06-18 | 2001-11-20 | Clavius Devices Inc. | Breath-activated metered-dose inhaler |
WO2006108563A1 (en) * | 2005-04-08 | 2006-10-19 | Nycomed Gmbh | Device for dry nebulization |
US20100292659A1 (en) * | 2008-12-26 | 2010-11-18 | Shoichi Nakamura | Carbon dioxide mist pressure bath system |
US7836882B1 (en) | 2005-01-07 | 2010-11-23 | Vetland Medical Sales And Services Llc | Electronic anesthesia delivery apparatus |
US20100298786A1 (en) * | 2008-12-26 | 2010-11-25 | Shoichi Nakamura | Carbon dioxide mist pressure bath system |
US20100305498A1 (en) * | 2008-12-04 | 2010-12-02 | Shoichi Nakamura | Gas mist pressure bath system |
US20110208116A1 (en) * | 2009-02-19 | 2011-08-25 | Acp Japanm Co., Ltd. | Gas mist pressure bath system |
US8267081B2 (en) | 2009-02-20 | 2012-09-18 | Baxter International Inc. | Inhaled anesthetic agent therapy and delivery system |
US20190099581A1 (en) * | 2017-09-29 | 2019-04-04 | General Electric Company | Systems for anesthetic agent vaporization |
US20220370734A1 (en) * | 2019-09-20 | 2022-11-24 | Medspray B.V. | Atomizer Device and Method for Preparation Thereof, and a Container Therefor |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE3523948A1 (de) * | 1985-07-04 | 1987-01-08 | Draegerwerk Ag | Vorrichtung zur versorgung von narkosemittelabgabeeinrichtungen |
SE450995B (sv) * | 1986-01-21 | 1987-08-24 | Gambro Engstrom Ab | Doserings- och forgasningsanordning, foretredesvis avsedd for tillforsel av narkosgas till en ferskgasstrom i en narkosanleggning |
GB2239807A (en) * | 1990-01-09 | 1991-07-17 | Boc Group Plc | Anaesthetic vaporiser |
DE4105971C2 (de) * | 1991-02-26 | 1999-06-24 | Draegerwerk Ag | Narkosemittelverdunster |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US458937A (en) * | 1891-09-01 | Edtjard blass | ||
US2342602A (en) * | 1942-01-02 | 1944-02-22 | Jr Hjalmar Reitz | Anesthetic apparatus |
US3128764A (en) * | 1960-10-06 | 1964-04-14 | Wilbur R Koehn | Anesthesizing apparatus |
US3171411A (en) * | 1961-01-03 | 1965-03-02 | Levine Walter | Anesthesia apparatus |
-
1969
- 1969-01-27 US US793932*A patent/US3593710A/en not_active Expired - Lifetime
-
1970
- 1970-01-22 NO NO0245/70A patent/NO123443B/no unknown
- 1970-01-23 GB GB3478/70A patent/GB1299311A/en not_active Expired
- 1970-01-23 DE DE19702003036 patent/DE2003036A1/de not_active Withdrawn
- 1970-01-26 SE SE00887/70A patent/SE358297B/xx unknown
- 1970-01-27 FR FR7002828A patent/FR2029491A1/fr not_active Withdrawn
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US458937A (en) * | 1891-09-01 | Edtjard blass | ||
US2342602A (en) * | 1942-01-02 | 1944-02-22 | Jr Hjalmar Reitz | Anesthetic apparatus |
US3128764A (en) * | 1960-10-06 | 1964-04-14 | Wilbur R Koehn | Anesthesizing apparatus |
US3171411A (en) * | 1961-01-03 | 1965-03-02 | Levine Walter | Anesthesia apparatus |
Cited By (27)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3809080A (en) * | 1970-06-24 | 1974-05-07 | Deaton Medical Co | Sterile liquid entraining system |
DE3315943A1 (de) * | 1983-05-02 | 1984-11-08 | Drägerwerk AG, 2400 Lübeck | Narkosemittelverdunster mit einem der verdunsterkammer parallelgeschalteten bypass mit einer ueberwachungseinrichtung |
US5068993A (en) * | 1990-10-05 | 1991-12-03 | Millar John G | Method and apparatus for anesthetizing caught fish |
US5535737A (en) * | 1993-11-16 | 1996-07-16 | The Boc Group, Inc. | Anesthetic vaporizers |
US5918595A (en) * | 1995-12-21 | 1999-07-06 | Siemens-Elema Ab | Method for vaporizing an anesthetic liquid and vaporizer operating according to the method |
US6318361B1 (en) * | 1998-06-18 | 2001-11-20 | Clavius Devices Inc. | Breath-activated metered-dose inhaler |
US6325062B1 (en) * | 1998-06-18 | 2001-12-04 | Clavius Devices, Inc. | Breath-activated metered-dose inhaler |
US6425392B1 (en) * | 1998-06-18 | 2002-07-30 | Clavius Devices, Inc. | Breath-activated metered-dose inhaler |
US6298845B1 (en) * | 1998-09-02 | 2001-10-09 | Siemens Elema Ab | Vaporizer |
US8567392B2 (en) | 2005-01-07 | 2013-10-29 | Vetland Medical Sales And Services Llc | Electronic anesthesia delivery apparatus |
US7836882B1 (en) | 2005-01-07 | 2010-11-23 | Vetland Medical Sales And Services Llc | Electronic anesthesia delivery apparatus |
US20110056491A1 (en) * | 2005-01-07 | 2011-03-10 | Brad Rumph | Electronic Anesthesia Delivery Apparatus |
WO2006108563A1 (en) * | 2005-04-08 | 2006-10-19 | Nycomed Gmbh | Device for dry nebulization |
US8230853B2 (en) * | 2008-12-04 | 2012-07-31 | Shoichi Nakamura | Gas mist pressure bath system |
US20100305498A1 (en) * | 2008-12-04 | 2010-12-02 | Shoichi Nakamura | Gas mist pressure bath system |
US20100298786A1 (en) * | 2008-12-26 | 2010-11-25 | Shoichi Nakamura | Carbon dioxide mist pressure bath system |
US8505532B2 (en) * | 2008-12-26 | 2013-08-13 | Acp Japan Co., Ltd. | Carbon dioxide mist pressure bath system |
US8517011B2 (en) * | 2008-12-26 | 2013-08-27 | Shoichi Nakamura | Carbon dioxide mist pressure bath system |
US20100292659A1 (en) * | 2008-12-26 | 2010-11-18 | Shoichi Nakamura | Carbon dioxide mist pressure bath system |
US20110208116A1 (en) * | 2009-02-19 | 2011-08-25 | Acp Japanm Co., Ltd. | Gas mist pressure bath system |
JPWO2010095607A1 (ja) * | 2009-02-19 | 2012-08-23 | 中村 正一 | ガスミスト圧浴システム |
US8585633B2 (en) * | 2009-02-19 | 2013-11-19 | Acp Japan | Gas mist pressure bath system |
JP5474042B2 (ja) * | 2009-02-19 | 2014-04-16 | 正一 中村 | ガスミスト圧浴システム |
US8267081B2 (en) | 2009-02-20 | 2012-09-18 | Baxter International Inc. | Inhaled anesthetic agent therapy and delivery system |
US20190099581A1 (en) * | 2017-09-29 | 2019-04-04 | General Electric Company | Systems for anesthetic agent vaporization |
US11179538B2 (en) * | 2017-09-29 | 2021-11-23 | General Electric Company | Systems for anesthetic agent vaporization |
US20220370734A1 (en) * | 2019-09-20 | 2022-11-24 | Medspray B.V. | Atomizer Device and Method for Preparation Thereof, and a Container Therefor |
Also Published As
Publication number | Publication date |
---|---|
FR2029491A1 (de) | 1970-10-23 |
DE2003036A1 (de) | 1970-07-30 |
GB1299311A (en) | 1972-12-13 |
NO123443B (de) | 1971-11-15 |
SE358297B (de) | 1973-07-30 |
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