|Publication number||USRE37379 E1|
|Application number||US 09/534,926|
|Publication date||18 Sep 2001|
|Filing date||23 Mar 2000|
|Priority date||14 Feb 1991|
|Publication number||09534926, 534926, US RE37379 E1, US RE37379E1, US-E1-RE37379, USRE37379 E1, USRE37379E1|
|Inventors||James Richard Spears|
|Original Assignee||Wayne State University|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (52), Non-Patent Citations (26), Referenced by (6), Classifications (60), Legal Events (4)|
|External Links: USPTO, USPTO Assignment, Espacenet|
This application is a continuation-in-part of application Ser. No. 08/353,137, filed on Dec. 9, 1994, now U.S. Pat. No. 5,599,296 which is a continuation-in-part of application Ser. No. 08/273,652, filed Jul. 12, 1994, now U.S. Pat. No. 5,569,180 which is a continuation-in-part of application Ser. No. 08/152,589, filed Nov. 15, 1993 now U.S. Pat. No. 5,407,426, which is a continuation-in-part of application Ser. No. 07/818,045, filed Jan. 8, 1992 now U.S. Pat. No. 5,261,875, which is a continuation of application Ser. No. 07/655,078, filed Feb. 14, 1991 now U.S. Pat. No. 5,086,620. The disclosures in each of the above-referenced cases are incorporated herein by reference.
This invention relates to an apparatus and method for generating a relatively high partial pressure of a gas in liquid by the use of an oxygenator.
In many industrial and clinical environments, it would be desirable to deliver a gas-enriched fluid to a site of interest. For example, in industrial applications it would be desirable to deliver carbon dioxide rapidly via a liquid transfer medium to a fire in order to extinguish the flame without the carbon dioxide becoming prematurely liberated from its dissolved state in the transfer medium. As another exampled the environmental problems of a toxic site cleanup may be ameliorated if a neutralizing or cleansing gaseous agent is delivered rapidly and at high concentration by a transporting medium into the area which requires cleansing.
In clinical applications, as has been disclosed in my previous patent applications referenced above, it would be highly desirable to treat patients, for example stroke victims, by having ready access to a system which would deliver an oxygen-enriched blood stream rapidly to the anatomical area where the need for oxygen enrichment is most acute.
For simplicity and brevity, the examples discussed below are primarily selected from clinical environments, although the applicability of the concepts and needs to be discussed to non-clinical, including industrial, environments will be apparent to those of skill in the art.
In the clinical area, if oxygen-supersaturated blood prematurely liberates oxygen at the wrong place and at the wrong time, an embolism may result. Its adverse consequences are well-known. For example, the stroke victim may experience a sudden attack of weakness affecting one side of the body as a consequence of an interruption to the flow of blood to the brain. The primary problem may be located in the heart or blood vessels. The effect on the brain is secondary. Blood flow may be prevented by clotting (thrombosis), a detached clot that lodges in an artery (embolus), or by rupture of an artery wall (hemorrhage). In any event, a severe interruption to the rate of mass transfer of oxygen-enriched blood occurs if laminar flow becomes disturbed by bubble formation and its consequent turbulent flow characteristics.
Ideally, the physician should be able to administer an oxygen-enriched, supersaturated blood flow in a laminar fashion quickly to a site of interest without premature liberation of oxygen after it leaves a delivery apparatus, and undergoes a pressure drop before arrival at the site requiring treatment.
What therefore is needed is a method and apparatus available to the physician and industrialist which will enable them to deliver gas-enriched fluids into environments of interest without premature formation of bubbles in the transferring medium.
In the past, the main objections to the clinical use of hyperbaric oxygen have been the risk of hemolysis and bubble emboli, together with the complexity of the equipment. Dawids and Engell, P
Disclosed is an apparatus and method for delivering a high partial pressure of a gas into a liquid. The apparatus includes a gas transfer device with contacting members in a gas-liquid contacting region thereof.
A reservoir of gas supplies the gas at a high pressure (P) to a flask of gas-depleted liquid. The flask is in liquid communication with the gas transfer device and in gaseous communication therewith at a pressure (p), where p is less than P.
The reservoir of gas provides a single source of hydrostatic pressure for urging the liquid through the contacting members and the gas around the contacting members so the gas does not diffuse across the contacting members.
The advantages of the present invention are readily apparent from the following detailed description of the best mode for carrying out the invention when taken in connection with the accompanying drawings.
FIG. 1 is a diagrammatic illustration of a representative apparatus in which a relatively high partial pressure of a gas can be achieved in a liquid.
Turning first to FIG. 1 of the drawing, there is depicted an apparatus 10 for delivering a high partial pressure of a gas into a liquid. The apparatus includes a gas transfer device 12 with a housing 14. Included in the housing is an upstream region 16, a downstream region 18, and a gas-liquid contacting region 20 with contacting members 22, such as microporous hollow fibers, or solid diffusible membranes. The contacting members 22 are located intermediate the upstream 16 and downstream 18 regions.
To receive a supply of liquid, a gas-depleted liquid inlet port 24 is provided in the upstream region 16. A liquid outlet port 28 is defined in the downstream region 18 for delivering gas-enriched liquid to a high resistance delivery channel 44, such as a catheter for medical applications. For industrial applications, a suitable delivery device such as a nozzle or its equivalents may be deployed.
A gas inlet port 32 is defined in the housing 14 for receiving the gas before contact with the liquid in the contacting region 20. Also provided in the housing 14 is a gas outlet port 34 for returning gas which is undissolved in the liquid.
A reservoir 36 of gas supplies the gas at a high pressure (P). In gaseous communications with the reservoir 36 is a flask 38 of gas-depleted liquid. If desired; means could be provided for continuous replenishment of the liquid. As illustrated in FIG. 1, the flask is in liquid communication with the liquid inlet port 24 and via a “T” junction 46 is in gaseous communication with the gas inlet port 32 of the gas transfer device 12. First and second regulators 40, 42 progressively reduce the gas pressure from a value represented by (P) in the flask 38 to a lower pressure (p) upon entry into the gas inlet port 32.
Thus, the disclosed apparatus enables the reservoir 36 of gas to provide a hydrostatic pressure which not only urges the liquid through the contacting members 22, but also urges the gas around the contacting members 22. In this way, the gas does not diffuse across the members, thus promoting mass transfer of the gas into the liquid.
The apparatus of the present invention will now be described in further detail. In one set of experiments, a pediatric hollow fiber (polypropylene) oxygenator (Turumo), which is normally used for oxygenation of venous blood during extracorporeal circulation in children was modified. One of two oxygen ports 32, 34 was connected to a reservoir 36 of oxygen. The partial pressure of the gas was adjusted with the regulator 40. A tubing from the latter was connected to a stainless steel tank 38 (Norris, 27 liter capacity) which had been filled with distilled water.
A liquid conduit section 48 extended below the meniscus of the liquid contained within the flask, which allowed flow of liquid from the bottom of the flask to the liquid in port 24 of the gas transfer device: or oxygenator 12. From a “T” junction 46, a second regulator 42 allowed adjustment of gas pressure to a value (p) that was 5 to 20 psi lower than the input pressure (P).
Tubing leading to the regulator 42 was connected to the gas inlet port 32 of the oxygenator 12.
The arrangement allowed a single tank 36 of oxygen to provide the driving hydrostatic pressure needed to (1) urge water through the interior of the hollow fibers 22 within the oxygenator 12 and (2) cause oxygen to flow around the outside of the bundle of hollow fibers 22.
The pressure difference across each hollow fiber ensured that oxygen did not directly diffuse across the hollow fibers in its gaseous state.
Three different runs performed with a hydrostatic pressure maintained at approximately 45 psi within the hollow fibers and an oxygen gas pressure of about 20 psi showed the same result.
When the effluent from the channel 44 was delivered into ordinary tap water through either a metal or plastic tubing having an internal diameter of approximately 0.5 mm, no bubbles were noted. The PO2 of the effluent was approximately 1800 mm Hg, a value similar to what would be predicted, assuming full equilibration of the gas pressure outside the fibers to that dissolved in water within the fibers.
It should be noted that no additional application of hydrostatic pressure was found to be necessary to prevent bubble formation.
It is likely that, at relatively low dissolved gas partial pressures, on the order of a few bar, the use of filtered water, which had been allowed to stand for many hours, in addition to sampling the water from the bottom of the tank, was effective for delivering relatively gas nuclei-free water to the oxygenator. Increasing the concentration of oxygen within the fibers only slightly by application of a few bar therefore does not result in bubble growth, i.e., generation of a high hydrostatic pressure after enrichment of the water with oxygen is unnecessary.
A hydrostatic pressure of only 45 psi would be insufficient, of course, for perfusion of coronary arteries through the small channels available in angioplasty catheters. However, the relatively large bore tubing (approximately 0.5 mm i.d.) which was adequate to preserve the stability of the oxygen-supersaturated water allowed flow rates in the 30 to 100 cc/min range. Catheters with similar channels would be quite suitable for delivery of an oxygen-supersaturated cardioplegic solution into the aortic root during cardiopulmonary bypass procedures.
In a separate run, a similar Terumo hollow fiber oxygenator was enclosed in a stainless steel housing, so that much higher pressures could be tested. A SciMed membrane oxygenator may also be used The arrangement for adjusting hydrostatic and oxygen gas pressures was similar to that noted above, but regulators which permitted a maximum pressure of about 500 psi were used. Hydrostatic pressure was maintained at about 20 to 50 psi greater than the oxygen gas pressure surrounding the bundle of fibers (i.e., the gas pressure inside the steel housing, external to the bundle).
Oxygen gas pressures of approximately 20 psi (to compare to the use of the oxygenator without the housing above) 150 psi, and 500 psi were tested. At 150 psi, no bubbles in the effluent were noted when silica fibers having an internal diameter of 150 microns or less were tested under tap water. However, at 500 psi, bubbles were noted in the effluent, even when a silica tubing with an i.d. of 50 microns was used.
The liquid output of the oxygenator was connected to an air-driven hydraulic pump (SC Hydraulics, Inc.). Hydrostatic pressure was increased to a range of about 0.7 kbar to 1.0 kbar within a T-tube mounted at the top of a 600 cc capacity high pressure vessel (High Pressure Equipment Corp.). The output from the T-tube was connected to a liquid regulator (Tescom), which allowed a reduction in pressure to a range of 4,000 psi or less. Following brief hydrostatic compression in the T-tube, the effluent, delivered at a pressure of about 3,000 to 4,000 psi through silica tubing having an i.d. of approximately 75 microns, was completely free of bubbles.
Thus, conventional oxygenators can be used to provide the high level of dissolved oxygen sought in clinical or industrial applications of gas-supersaturated liquids. At relatively low gas pressures, on the order of a few bar, application of additional hydrostatic pressure, after enrichment of the liquid with the gas, is unnecessary if the water is made relatively bubble-free by filtration and/or prolonged standing, as in the 3 runs performed at a gas pressure of about 20 psi. Much higher dissolved gas pressures still benefit from a further increase in hydrostatic pressure, as described in prior disclosures.
Experimental results have shown that the disclosed apparatus enables higher pressures to be safely achieved in order to produce a gas concentration exceeding two bar, both rapidly and continuously. Thus, the disclosed apparatus, in combination with a high resistance delivery system, allows the gas-enriched fluid to be injected into a one bar environment without bubble formation.
It will be apparent to those of ordinary skill in the art that the gas-liquid contacting region may embodied in an oxygenator or a membrane, or their equivalents. If a membrane oxygenator is used, a silicon membrane is preferred. Suitable oxygenators include those manufactured by Hoechst Celanese (LIQUI-CEL® CONTACTORS) and by Medtronic, (MAXIMA PLUS198 OXYGENATOR) and their equivalents.
In addition to oxygen as a gas of choice, air can be used usefully in combination with water or gasoline, for example, to promote efficient combustion in an internal combustion engine. Water can be used in combination with carbon dioxide or nitrogen in certain industrial applications.
While the best mode for carrying out the invention has been described in detail, those familiar with the art to which this invention relates will recognize various alternative designs and embodiments for practicing the invention as defined by the following claims.
|Cited Patent||Filing date||Publication date||Applicant||Title|
|US3142296||31 May 1962||28 Jul 1964||Jack W Love||Blood oxygenator|
|US3437450||4 Jan 1965||8 Apr 1969||Greenwood James M||Hyperbaric heart pump oxygenator with hypothermia|
|US3721231||1 Feb 1971||20 Mar 1973||Becton Dickinson Co||Catheter for high pressure injections|
|US3881483||12 Sep 1973||6 May 1975||Rhone Poulenc Sa||Extracorporeal blood circuit|
|US3927981||30 Aug 1973||23 Dec 1975||Rhone Poulenc Sa||Membrane-type blood oxygenator with recycle of oxygen-containing gas|
|US4008047||26 Dec 1974||15 Feb 1977||North Star Research Institute||Blood compatible polymers for blood oxygenation devices|
|US4122858||23 Mar 1977||31 Oct 1978||Peter Schiff||Adapter for intra-aortic balloons and the like|
|US4205042||23 Jun 1978||27 May 1980||Cobe Laboratories, Inc.||Blood oxygenator with a gas filter|
|US4401431||26 Jun 1981||30 Aug 1983||Arp Leon J||Blood pump and oxygenator monitor-controller and display device|
|US4445896||18 Mar 1982||1 May 1984||Cook, Inc.||Catheter plug|
|US4493692||29 Sep 1982||15 Jan 1985||Reed Charles C||Blood gas concentration control apparatus and method|
|US4602987||24 Sep 1984||29 Jul 1986||Aquanautics Corporation||System for the extraction and utilization of oxygen from fluids|
|US4610661||13 Jun 1984||9 Sep 1986||Possis Medical, Incorporated||Perfusion device|
|US4666668||26 Mar 1986||19 May 1987||Lidorenko Nikolai S||Gas-permeable membrane, and blood oxygenator based on gas-permeable membrane|
|US4686085||23 Feb 1984||11 Aug 1987||Thomas Jefferson University||Stroke treatment utilizing extravascular circulation of oxygenated synthetic nutrients to treat tissue hypoxic and ischemic disorders|
|US4808378||10 Apr 1987||28 Feb 1989||Senko Medical Instrument Mfg. Co., Ltd.||Blood oxygenator|
|US4828543||3 Apr 1986||9 May 1989||Weiss Paul I||Extracorporeal circulation apparatus|
|US4834719||28 Apr 1986||30 May 1989||Cordis Corporation||Quick connect/disconnect tubing adapter|
|US4874581||7 Jul 1988||17 Oct 1989||Baxter International Inc.||O2 /CO2 control in blood oxygenators|
|US4877031||22 Jul 1988||31 Oct 1989||Advanced Cardiovascular Systems, Inc.||Steerable perfusion dilatation catheter|
|US4919895||18 Jun 1987||24 Apr 1990||Alpha Therapeutic Corporation||Apparatus for oxygenation of liquid state dissolved oxygen-carrying formulation|
|US4968483||4 Nov 1987||6 Nov 1990||Quarzlampenfabrik Dr.-Ing. Felix W. Muller Gmbh & Co. Kg||Apparatus for the production of oxygenated blood|
|US5021044||30 Jan 1989||4 Jun 1991||Advanced Cardiovascular Systems, Inc.||Catheter for even distribution of therapeutic fluids|
|US5039482||9 Dec 1988||13 Aug 1991||Shiley Inc.||Integrated unit for extracorporeal blood circuits|
|US5069661||18 May 1988||3 Dec 1991||Brigham And Women's Hospital||Circulatory support system|
|US5084011||25 Jan 1990||28 Jan 1992||Grady Daniel J||Method for oxygen therapy using hyperbarically oxygenated liquid|
|US5110548||10 Mar 1988||5 May 1992||Montevecchi Franco M||Apparatus for concurrently oxgenating and pumping blood circulated extra-corporeally in cardiovascular systems|
|US5114423||9 May 1990||19 May 1992||Advanced Cardiovascular Systems, Inc.||Dilatation catheter assembly with heated balloon|
|US5137513||2 Jul 1990||11 Aug 1992||Advanced Cardiovoascular Systems, Inc.||Perfusion dilatation catheter|
|US5152964||15 Feb 1991||6 Oct 1992||Minnesota Mining And Manufacturing Company||Membrane blood oxygenator|
|US5158533||26 Mar 1991||27 Oct 1992||Gish Biomedical, Inc.||Combined cardiotomy/venous/pleural drainage autotransfusion unit with filter and integral manometer and water seal|
|US5158540||22 May 1990||27 Oct 1992||Leocor, Inc.||Perfusion catheter|
|US5180364||3 Jul 1991||19 Jan 1993||Robert Ginsburg||Valved self-perfusing catheter guide|
|US5186713||1 Nov 1990||16 Feb 1993||Baxter International Inc.||Extracorporeal blood oxygenation system and method for providing hemoperfusion during transluminal balloon angioplasty procedures|
|US5195971||10 Feb 1992||23 Mar 1993||Advanced Cardiovascular Systems, Inc.||Perfusion type dilatation catheter|
|US5277176||29 Jun 1992||11 Jan 1994||Habashi Nader M||Extracorporeal lung assistance apparatus and process|
|US5334142||9 Sep 1991||2 Aug 1994||New York University||Selective aortic perfusion system|
|US5356388||22 Sep 1992||18 Oct 1994||Target Therapeutics, Inc.||Perfusion catheter system|
|US5368555||29 Dec 1992||29 Nov 1994||Hepatix, Inc.||Organ support system|
|US5382407||5 Oct 1992||17 Jan 1995||Minnesota Mining And Manufacturing Company||Membrane blood oxygenator|
|US5407426||15 Nov 1993||18 Apr 1995||Wayne State University||Method and apparatus for delivering oxygen into blood|
|US5413558||1 Oct 1993||9 May 1995||New York University||Selective aortic perfusion system for use during CPR|
|US5569180||12 Jul 1994||29 Oct 1996||Wayne State University||Method for delivering a gas-supersaturated fluid to a gas-depleted site and use thereof|
|US5591399||7 Jun 1995||7 Jan 1997||Goldman; Julian M.||System for diagnosing oxygenator failure|
|US5670094||25 Jan 1996||23 Sep 1997||Ebara Corporation||Method of and apparatus for producing ozonized water|
|US5695717||15 Nov 1996||9 Dec 1997||Fresenius Ag||Gas exchange apparatus|
|US5735934||30 May 1995||7 Apr 1998||Wayne State University||Method for delivering a gas-supersaturated fluid to a gas-depleted site and use thereof|
|US5752929||7 Jun 1995||19 May 1998||Life Resuscitation Technologies, Inc.||Method of preserving organs other than the brain|
|US5797874||5 Jun 1995||25 Aug 1998||Wayne State University||Method of delivery of gas-supersaturated liquids|
|US5814004||7 Jun 1995||29 Sep 1998||Tamari; Yehuda||System for regulating pressure within an extracorporeal circuit|
|DE2343845A1||30 Aug 1973||7 Mar 1974||Rhone Poulenc Sa||Kuenstliche lunge|
|DE2649126A1||28 Oct 1976||3 May 1978||Linde Ag||Verfahren und vorrichtung zum begasen einer fluessigkeit|
|1||Armand A. Lefemine et al., "Increased oxygen pressure to improve the efficiency of membrane oxygenators," Medical Instrumentation, vol. 10, No. 6, pp. 304-308, Nov.-Dec. 1976.|
|2||C. Boe et al., "Use of Hyperbaric Oxygen as Oxygen Source in Extracorporeal Oxygenation of Blood," Physiological and Clinical Aspects of Oxygenator Design, Elsevier North-Holland Biomedical Press, Luxembourg, 1976.|
|3||E.H. Spratt et al., "Evaluation of a Membrane Oxygenator For Clinical Cardiopulmonary Bypass," Trans Am Soc Artif Intern Organs, vol. XXVII, pp. 285-288, 1981.|
|4||Edvard A. Hemmingsen, "Cavitation in gas-supersaturated soluations," Journal of Applied Physics, vol. 46, No. 1, pp. 213-218, Jan. 1976.|
|5||F. Valdés et al., "Ex Vivo Evaluation of a New Capillary Membrane Oxygenator," Trans Am Soc Artif Intern Organs, vol. XXVII, pp. 270-275, 1981.|
|6||F.M. Servas et al., "High Efficiency Membrane Oxygenator," Trans Am Soc Artif Intern Organs, vol. XXIX, pp. 231-236, 1983.|
|7||H. Matsuda et al., "Evaluation of a New Siliconized Polypropylene Hollow Fiber Membrane Lung for ECMO," Trans Am Soc Artif Intern Organs, vol. XXXI, pp. 599-603, 1985.|
|8||J. Mieszala et al., "Evaluation of a New Low Pressure Drop Membrane Oxygenator," Trans Am Soc Artif Intern Organs, vol. XXVIII, pp. 342-349, 1982.|
|9||J.B. Zwischenberger et al., "Total Respiratory Support With Single Cannula Venovenous ECMO: Double Lumen Continuous Flow vs. Single Lumen Tidal Flow," Trans Am Soc Artif Intern Organs, vol. XXXI, pp. 610-615, 1985.|
|10||JDS Gaylor et al., "Membrane oxygenators: influence of design on performance," Perfusion, vol. 9, No. 3, pp. 173-180, 1994.|
|11||K.E. Karlson et al., "Total cardiopulmonary bypass with a new microporous Teflon membrane oxygenator," Surgery, vol. 76, No. 6, pp. 935-945, Dec. 1974.|
|12||Karl E. Karlson et al., "Initial Clinical Experience With a Low Pressure Drop Membrane Oxygenator for Cardiopulmonary Bypass in Adult Patients," The American Journal of Surgery, vol. 147, pp. 447-450, Apr. 1984.|
|13||Michael T. Snider et al., Small Intrapulmonary Artery Lung Prototypes: Design, Construction, and In Vitro Water Testing, ASAIO Journal, pp. M533-M539, 1994.|
|14||Philip A. Drinker et al., "Engineering Aspects of ECMO Technology," Artifical Organs, vol. 2, No. 1, pp. 6-11, Feb. 1978.|
|15||Pieter Stroev et al., "Supersaturated fluorocarbon as an oxygen source," Physiological and Clinical Aspects of Oxygenator Design, Elsevier North-Holland Biomedical Press, pp. 129-139, Luxembourg, 1976.|
|16||Robert C. Eberhart et al., "Mathematical and Experimental Methods for Design and Evaluation of Membrane Oxygenators," Artificial Organs, vol. 2, No. 1, pp. 19-34, Feb. 1978.|
|17||Robert H. Bartlett et al., "Instrumentation for cardiopulmonary bypass-past, present, and future," Medical Instrumentation, vol. 10, No. 2, pp. 119-124, Mar.-Apr. 1976.|
|18||Robert H. Bartlett et al., "Instrumentation for cardiopulmonary bypass—past, present, and future," Medical Instrumentation, vol. 10, No. 2, pp. 119-124, Mar.-Apr. 1976.|
|19||S. Marlow et al., "A pO2 Regulation System For Membrane Oxygenators," American Society For Artificial Internal Organs, vol. XXVII, pp. 299-303, 1981.|
|20||S. Ohtake et al., "Experimental Evaluation of Pumpless Arteriovenous ECMO With Polypropylene Hollow Fiber Membrane Oxygenator for Partial Respiratory Support," Trans Am Soc Artif Intern Organs, vol. XXIX, pp. 237-241, 1983.|
|21||Steven N. Vaslef, et al., "Design and Evaluation of a New, Low Pressure Loss, Implantable Artificial Lung," ASAIO Journal, vol. 40, No. 3, pp. M522-M526, Jul.-Sep. 1994.|
|22||T. Dohi et al., "Development and Clinical Application of a New Membrane Oxygenator Using a Microporous Polysulfone Membrane," Trans Am Soc Artif Intern Organs, vol. XXVIII, pp. 338-341, 1982.|
|23||T. Kawamura et al., "ECMO in pumpless RV to LA bypass," Trans Am Soc Artif Intern Organs, vol. XXXI, pp. 616-621, 1985.|
|24||Terry G. Campbell, Changing Criteria for the Articial Lung Historic Controls on the Technology of ECMO,: ASAIO Journal, vol. 40, No. 2, pp. 109-120, Apr.-Jun. 1994.|
|25||W. Zingg et al., "Improving the Efficiency of a Tubular Membrane Oxygenator," Med. Progr. Technol. 4, pp. 139-145, 1976.|
|26||Yehuda Tamari et al., "The Effect of High Pressure on Microporous Membrane Oxygenator Failure," Artificial Organs, vol. 15, No. 1, pp. 15-22, Feb. 1991.|
|Citing Patent||Filing date||Publication date||Applicant||Title|
|US6607698 *||15 Aug 1997||19 Aug 2003||Therox, Inc.||Method for generalized extracorporeal support|
|US6849235||13 Mar 2003||1 Feb 2005||Therox, Inc.||Method of forming gas-enriched fluid|
|US6855291||7 Mar 2003||15 Feb 2005||Therox, Inc.||Method of blood oxygenation|
|US6899847||11 Mar 2003||31 May 2005||Therox, Inc.||Apparatus for blood oxygenation|
|US7927544||21 Apr 2006||19 Apr 2011||Alung Technologies, Inc.||Paracorporeal respiratory assist lung|
|US8647569||11 Apr 2011||11 Feb 2014||ALung Technologies, Inc||Paracorporeal respiratory assist lung|
|U.S. Classification||422/44, 604/24, 422/45, 604/4.01, 261/95, 422/48, 261/101, 604/26|
|International Classification||A61K9/50, C01B13/00, B01F3/04, A61M1/16, A61M1/32, B01F3/08, C01B13/02, A61M25/00, C01B5/00, C12M1/04, A23L2/54, D21C9/147, B01J13/04|
|Cooperative Classification||A61M2025/0057, A61M1/32, B01F2215/0078, A61M25/0026, C01B13/02, C01B5/00, A61M1/1678, A61M1/1698, A61K9/5089, B01F2215/0075, D21C9/147, A23L2/54, A61M25/09, B01J13/04, C01B13/00, B01F2003/04879, A61M25/007, B01F3/04099, B01F2215/0034, B01F3/04985, A61M2202/0476, B01F3/04439, B01F2215/0052, B01F3/0876, B01F2003/04893|
|European Classification||A61M25/00T10C, A61M25/00R1M, B01F3/04P, A61M1/32, B01J13/04, A61K9/50P, A23L2/54, B01F3/04C2, A61M1/16S, B01F3/08F4, D21C9/147, C01B13/02, C01B13/00, C01B5/00|
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