Abstract:
An apparatus for producing gas for use in medical applications. The apparatus includes a compressed gas unit having at least one container of compressed gas and a solenoid valve. An adjustable pressure regulator communicably connected to the gas container, separate and distinct from the solenoid valve, is adjusted to control the pressure of the gas provided from the container to the solenoid valve. An electrical power source is connected to the solenoid valve. A pressure activated electronic switch connected to the power source is responsive to a selected amount of voluntary fingertip, pressure for opening the solenoid valve to transmit the gas therethrough to a conduit, which further transmits the gas to a destination for use or storage.

Description:
RELATED APPLICATIONS 
     This application is a continuation in part of U.S. patent application Ser. No. 13/068,680 filed May 17, 2011 which is a continuation in part of U.S. patent application Ser. No. 12/652,845 filed Jan. 8, 2010, which is a continuation in part of U.S. patent application Ser. No. 12/210,368 filed Sep. 15, 2008, which is a continuation in part of U.S. patent application Ser. No. 11/945,674 filed Nov. 27, 2007, now U.S. Pat. No. 7,543,760, which claims the benefit of U.S. Provisional Patent Application Ser. No. 60/867,323 filed Nov. 27, 2006, the disclosures of which are incorporated herein by reference in their entirety. 
    
    
     FIELD OF THE INVENTION 
     This invention relates to a portable system for safely and efficiently producing and delivering CO 2  and other gases for use in medical applications. 
     BACKGROUND OF THE INVENTION 
     Conventional devices for delivering gas such as carbon dioxide (CO 2 ) for use in medical procedures typically utilize large storage tanks and regulators. Such devices are dangerous because of the risk of a seal, valve or part malfunction, which can produce a projectile in a medical setting. In addition, existing tank systems are quite expensive, extremely cumbersome and usually impractical to transport to off-site locations. These systems typically require a considerable amount of storage space. Current tanks also require filling at a filling station, which can involve the transport of a large quantity of gas such as CO 2 . Pressurized gas tanks can explode in the event of a motor vehicle crash. Re-fillable tanks can also exhibit rust, bacteria and contamination, which are not acceptable in a medical environment. 
     SUMMARY OF THE INVENTION 
     The present invention is intended to provide a portable, safe, reliable, and convenient source of medical gas such as CO 2  to health care professionals in hospital or medical office settings where a small volume of CO 2  or other gases is needed. The device is intended for general use by physicians and is not intended to be used for any specific medical treatment or procedure. The present invention is simple to manufacture and use because it does not require large regulators, an external power source, cumbersome large tanks or impellers for dispensing medical grade CO 2 . 
     The portable apparatus of the present invention utilizes a source of compressed gas to produce the desired pressure and airflow for the effective transformation of medical CO 2  liquid to medical grade CO 2  gas. 
     The present invention provides for a novel portable apparatus for delivering a medical grade gas such as CO 2 . In a preferred embodiment the apparatus includes a portable compressed gas unit having at least one cylinder containing a compressed medical gas. A solenoid valve is communicably connected to the cylinder. There is a separate pressure adjustable gas regulator for selectively adjusting the pressure of the compressed gas provided from the cylinder to the solenoid. A source of electrical power is connected to the solenoid and an electronic switch is interconnected between the source of electrical power and the solenoid. The switch is adapted to be manually activated by a selected amount of voluntary fingertip pressure for selectively opening the solenoid to transmit pressure adjusted gas therethrough. A conduit is communicably attached to an outlet of the solenoid for delivering the transmitted gas to a destination where the gas may be used in a medical procedure or stored for later use. 
     The compressed gas may be any gas suitable for medical applications. Suitable compressed gases may include carbon dioxide, atmospheric air, nitrogen, helium and/or mixtures thereof. The compressed gas is contained in one or more compressed gas containers such as cylindrical cartridges. The electrical power source may be delivered by batteries providing between about 3-24 volts. Preferably, the electronic switch activates the solenoid when the switch is selectively depressed by fingertip pressure. 
     The conduit may include a hose and the destination may include a gas storage container. The container may include a reservoir bag or other reservoir or receptacle. 
     The system of this invention is particularly beneficial for delivering CO 2  for medical use. In medical uses, CO 2  is used because it is safer and has fewer complications than air or oxygen in the same uses. CO 2  diffuses more naturally in body tissue and is absorbed in the body more rapidly with fewer side effects. CO 2  used in decompartmentalization of tissues, arteries, veins and nerves and for radiological imaging, cardiac imagining, evaluation of vascularity of the heart and surrounding tissues, oncology and urology diagnostics. It is specifically used for imaging by infiltrating the tissues, body cavities and abdomen for better visualization. The CO 2  can also expand internal body cavities and tissues thereby enabling better diagnostic techniques. 
     The pressure adjusted CO 2  gas provided by the system of this invention is ultimately delivered to a reservoir of the physician&#39;s choice. For example, the CO 2  or other gas may be delivered to a medical reservoir bag or other system for temporary storage. The bag is a reservoir that is used to house the CO 2  provided from existing CO 2  tanks. The stored CO 2  may be used as needed by various medical devices for applications such as imaging, differentiation of tissues, arterial/venus/neurological separation, and treatment of stretch marks, facial wrinkles and dark circles. The separate pressure regulator interconnected between the gas container and the solenoid allows the pressure of the CO 2  or other gas to be controlled from about 0 psi to 120 psi. This allows the gas to be used for a variety of medical applications. 
     The system is portable, compact, and electronic so that it is convenient to utilize in the field for portable medical uses, military field uses and any other use requiring CO 2  or other medical gas for its performance. The system is safer than existing tank systems because it eliminates the risk of seal, valve or part malfunction, the potential for a disastrous explosion and the unwanted production of projectiles in a medical setting. It also eliminates the rust, dirt, bacteria and contaminants that can be present in refillable tanks. The system requires very little space to store and is much easier to use with a simple push button actuator to initiate operation using fingertip pressure. The system of the invention is much less expensive than current tank systems. In addition, the system utilizes compact compressed gas cartridges which can be delivered and transported in a small box. The compressed gas cartridges do not have to be transported to a filling station and do not present a risk of explosion in the event of a motor vehicle accident. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Other objects, features and advantages will occur from the following description of a preferred embodiment and the accompanying drawings, in which: 
         FIG. 1  is a side perspective and partly schematic view of a preferred compressed gas unit in accordance with this invention including compressed gas (CO 2 ) cylinders, a pressure adjustable regulator and a separate solenoid; 
         FIG. 2  is a schematic front view of an alternative compressed gas unit enclosed in a housing; and 
         FIG. 3  depicts a schematic layout of the components of the compressed gas unit of  FIG. 2 . 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     In  FIG. 1 , compressed gas unit  1  comprises a solenoid  55  with at least one compressed gas (CO 2 ) cylinder  27  connected communicably to the solenoid. In one embodiment, compressed gas cylinder or cartridge  27  is 25 g or larger. Compressed gas cylinder  27  is secured into position to unit  1  by means of cylinder cartridge puncture valve  26  and a fitting  74 . In a preferred embodiment, cylinder cartridge puncture valve  26  has a mechanism for piercing cylinder  27 , as is known in the art, and for holding or securing said cylinder in place. Compressed air is delivered to solenoid  55  from compressed gas cylinder  27  through cylinder cartridge puncture valve  26  and channel  73  of fitting  74 . Conduit  73  of fitting  74  communicates with a threaded conduit  38  described more fully below. 
     Compressed gas unit  1  has at least one battery  65  held in place by battery holder  42 , for providing electrical power by which solenoid  55  may be selectively activated and opened by a pressure activation switch or actuator  37 . The switch is designed so that solenoid  55  is opened when a physician or other medical personnel engages the switch by voluntarily applying a small predetermined amount of fingertip pressure to switch  37 . It is not activated by a breathing sensor or other actuators designed to be operated by involuntary movement of the user&#39;s body. Battery  65  supplies power to solenoid  55  through switch wire assembly  23 , which is connected to activation switch  37 . This switch is mounted to a pressure nut  32  carried on threaded conduit  38 . Compressed air unit  1  has electrical wiring  39  for providing necessary electricity from switch  37  to solenoid  55 . 
     Unit  1  also comprises a separate black rock regulator  140 , which is distinct from solenoid  55 . Regulator  140  is controlled or adjusted by a regulator adjustment knob  30  to provide a selected level of pressure to the gas provided to the solenoid. Black rock regulator  140  is communicably connected to unit  1  by an elbow pipe  40 . The elbow pipe includes a threaded vertical conduit segment  41  joined to regulator  140  through a connector nut and the threaded horizontal conduit  38 , which is engaged by pressure nut  32 . 
     Compressed gas cylinder  27  is secured to unit  1  by cartridge puncture valve  26  as is commonly known. In one embodiment, compressed gas cylinder  27  is a 25 g cylinder. Alternative capacities (e.g. 16, 36, 45 grams) may be used within the scope of this invention. Compressed air leaves black rock regulator  140  at the regulator adjusted pressure through a 10/32″ hose port  12   b  and flows through a hose junction  22 , by means of ⅛″ pressure hose  54 , until reaching the 10/32″ hose port  12  affixed to solenoid  55 , From hose part  12 , the compressed air enters solenoid  55 . Compressed air unit  1  also has an outlet air port  25 , which is connected to solenoid  55  through intermediate 10/32″ hose port  12   a  for transporting compressed gas, namely CO 2  from solenoid  55  in compressed gas unit  1  to the storage container or other destination for medical gas whenever the solenoid is opened. Outlet gas may be monitored with pressure gauge  52  connected to hose junction  22  through a conduit  45  having threads  46 . The threaded end of conduit  45  interengages a nut  48  carried by hose junction  22 . 
     In certain embodiments a second compressed gas cylinder or cartridge  28 , featuring a 16 g or 25 g compressed gas cylinder, may be used in addition to or in lieu of gas cylinder  27 . In still other embodiments a larger compressed gas cylinder and expansion chamber may be substituted for the gas cartridges previously described in accordance with the invention. The size and number of compressed gas containers are not limitations of the invention. 
       FIGS. 2 and 3  depict an alternative embodiment of a compressed gas unit  1   a  wherein venous components of the gas unit are enclosed in a housing  75   a . The components of unit  1   a  are designated by reference numerals that correspond to those of the previously described embodiment and further include lower case “a” designations. In particular, a CO 2  cartridge  27   a  is connected by a puncture valve  26   a  to a regulator  140   a . The regulator is controlled by an adjustment knob  30   a . Regulator  140   a  is connected through a conduit  54   a  to both a pressure gauge  52   a  and a solenoid  55   a . More particularly, gauge  52   a  is connected to a coupling  48   a . Solenoid  55   a  is powered by a battery  65   a , which is itself held in place within the housing by a holder  42   a . A user accessible Luer fitting  25   a  is communicably connected to solenoid  55   a  and extends exteriorly of housing  75   a.    
     Unit  1   a  is activated to selectively open solenoid  55   a  by manually engaging switch  37   a  through voluntary fingertip pressure. This transmits the pressure regulated CO 2  or other gas through solenoid  55   a  and fitting  25   a . The compressed gas unit thereby operates in a manner analogous to that previously described to provide pressure adjusted CO 2  from cartridge  27   a  through Luer fitting  25   a  to a gas storage container or other destination for the medical gas. The following are preferred examples of such applications. 
     EXAMPLE OF USE 
     It is contemplated that the apparatus of the present invention be used in methods and procedures requiring delivery of medical gas. The following are examples of such applications: 
     CO 2  is useful in the following arterial procedures: abdominal aortography (aneurysm, stenosis) iliac arteriography (stenosis), runoff analysis of the lower extremities (stenosis, occlusion), renal arteriography (stenosis, arteriovenuous fistula [AVF], aneurysm, tumor), renal arterial transplantation (stenosis, bleeding, AVF), and visceral arteriography (anatomy, bleeding, AVF, tumor). 
     CO 2  is useful in the following venous procedures: venography of the upper extremities (stenosis, thrombosis), inferior vena cavography (prior to filter insertion), wedged hepatic venography (visualization of portal vein), direct portography (anatomy, varices), and splenoportograpy (visualization of portal vein). 
     CO 2  is likewise useful in the following interventional procedures: balloon angioplasty (arterial venous), stent placement (arterial, venous), embolization (renal, hepatic, pelvic, mesenteric) transjugular intrahepatic portacaval shunt creation, and transcatheter biopsy (hepatic, renal). 
     Angiography is performed by injecting microbubbles of CO 2  through a catheter placed in the hepatic artery following conventional hepatic angiography. Vascular findings on US angiography can be classified into four patterns depending on the tumor vascularity relative to the surrounding liver parenchyma: hypervascular, isovascular, hypovascular, and a vascular spot in a hypovascular background. 
     Improved CT colonography, an accurate screening tool for colorectal cancer, is performed using a small flexible rectal catheter with automated CO 2  delivery. This accomplishes improved distention with less post-procedural discomfort. 
     Carbon dioxide (CO 2 ) gas is used as an alternative contrast to iodinated contrast material. The gas produces negative contrast because of its low atomic number and its low density compared with the surrounding tissues. When injected into a blood vessel, carbon dioxide bubbles displace blood, allowing vascular imaging. Because of the low density of the gas, a digital substraction angiographic technique is necessary for optimal imaging. The gas bubble can be visible on a standard radiograph and fluoroscopic image. 
     CO 2  insufflation for colonoscopy improves productivity of the endoscopy unit. 
     Endoscopic thyroid resection involves creating a working space within the neck using CO 2  insufflation devices, with both axillary and neck approaches as starting points for dissection. 
     CO 2  unsufflators are used during laparoscopic surgery. 
     Because of the lack of nephrotoxicity and allergic reactions, CO 2  is increasingly used as a contrast agent for diagnostic angiography and vascular interventions in both the arterial and venous circulation. 
     CO 2  is particularly useful in patients with renal insufficiency or a history of hypersensitivity to iodinated contrast medium. 
     CO 2  is compressible during injection and extends in the vessel as it exits the catheter. 
     CO 2  is lighter than blood plasma; therefore, it floats above the blood. When injected into a large vessel such as the aorta or inferior vena cava, CO 2  bubbles flow along the anterior part of the vessel with incomplete blood displacement along the posterior portion. 
     CO2 causes no allergic reaction. Because CO 2  is a natural byproduct, it has no likelihood of causing a hypersensitivity reaction. Therefore, the gas is an ideal alternative. Unlimited amounts of CO 2  can be used for vascular imaging because the gas is effectively eliminated by means of respiration. 
     CO 2  is partially useful in patients with compromised cardiac and renal function who are undergoing complex vascular interventions. 
     Intranasal carbon dioxide is very promising as a safe and effective treatment to provide rapid relief for seasonal allergic rhinitis. 
     CO 2  is used for transient respiratory stimulation; encouragement of deep breathing and coughing to prevent or treat aterectasis; to provide a close-to-physiological atmosphere (mixed with oxygen) for the operation of artificial organs such as the membrane dialyzer (kidney) and the pump oxygenator; and for injection into body cavities during surgical procedures. 
     Medical asepsis is accomplished by using CO 2  an implant devices prior to surgical implantation. CO 2  may be effectively delivered to a foam generating tip for creating a medical foam for use in wound care and hair loss treatment. 
     Additionally, the present invention is used in methods requiring the deliver of other gasses such as: Carbon Dioxide U.S.P., Medical Air U.S.P., Helium U.S.P., Nitrogen U.S.P., Nitrous Oxide U.S.P., Oxygen U.S.P. and any combination thereof. 
     In one embodiment, the present invention provides for an apparatus and use in a method whereby delivery of a gas alone is desired. The delivery of gas is independent of systems whereby a gas is delivered as a carrier for medications or other materials. 
     While the invention has been described in its preferred form or embodiment with some degree of particularity, it is understood that this description has been given only by way of example, and that numerous changes in the details of construction, fabrication, and use, including the combination and arrangement of parts, may be made without departing from the spirit and scope of the invention. 
     Although specific features of the invention are shown in some of the drawings and not others, this is for convenience only, as each feature may be combined with any and all of the other features in accordance with this invention. 
     Other embodiments will occur to those skilled in the art and are within the following claims: