Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
  • B01D53/02—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by adsorption, e.g. preparative gas chromatography
  • B01D53/04—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by adsorption, e.g. preparative gas chromatography with stationary adsorbents
  • B01D53/0407—Constructional details of adsorbing systems
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D2257/00—Components to be removed
  • B01D2257/50—Carbon oxides
  • B01D2257/504—Carbon dioxide
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D2259/00—Type of treatment
  • B01D2259/40—Further details for adsorption processes and devices
  • B01D2259/40007—Controlling pressure or temperature swing adsorption
  • B01D2259/40009—Controlling pressure or temperature swing adsorption using sensors or gas analysers
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D2259/00—Type of treatment
  • B01D2259/45—Gas separation or purification devices adapted for specific applications
  • B01D2259/4533—Gas separation or purification devices adapted for specific applications for medical purposes
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D2259/00—Type of treatment
  • B01D2259/45—Gas separation or purification devices adapted for specific applications
  • B01D2259/455—Gas separation or purification devices adapted for specific applications for transportable use
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02C—CAPTURE, STORAGE, SEQUESTRATION OR DISPOSAL OF GREENHOUSE GASES [GHG]
  • Y02C20/00—Capture or disposal of greenhouse gases
  • Y02C20/40—Capture or disposal of greenhouse gases of CO2

Definitions

• the present invention refers to a carbon dioxide (CO 2 ) absorbing system, which is connected to respiratory devices, especially, but not exclusively, used to administer anesthesia in patients. More specifically, the present invention refers to a carbon dioxide (CO 2 ) absorbing system appropriated for the use of anesthesia under low flow with re-inhalation in newly born, pediatric and adult patients. Furthermore, the carbon dioxide (CO 2 ) absorbing system object of this invention promotes the appropriate, efficient and safe inhalation and exhalation of patients with no risk of contamination or any other failure which may damage respiratory cycles.
• the inhalatory administration of anesthesia containing halogenated agents is made by means of a respiratory circuit that allows the partial re-inhalation of gas exhaled by patients.
• the re-inhalation circuit has the purpose to reduce the cost of anesthesia agents, since the organism of the patient through each respiratory cycle absorbs only a small quantity of such agents. Furthermore, this circuit allows the reduction of environmental pollution caused by the exhaustion of said anesthesia agents.
• Currently known respiratory devices show robust, large and heavy structures comprising complex devices, which eventually make staff handling difficult during anesthesia administration. Consequently, they present high purchasing cost for hospitals, medical clinics, etc.
• CO 2 absorbing systems known in the state of the art that allows the re-inhalation need a reservoir, which is filled in with a material that absorbs CO 2 from re-inhaled gases. Soda lime is commonly used. For this reason, reservoirs usually have a high volume, about 2 liters of capacity, in order to allow the longest and most continuous possible use of the equipment, since soda lime becomes saturated and loses the capacity to absorb CO 2 with time. However, since such reservoirs have high volume capacity, CO 2 absorbing systems with re-inhalation known in the state of the art show various inconveniences because the volume of the reservoir is a compressible space that during the inhaling step, part of which that is intended to the patient, remains compressed in the circuit. This significantly reduces the effective volume received by the patient.
• soda lime is only substituted after its complete saturation, which means the use of the same soda lime in various different patients due the high capacity of the reservoir.
• Such reuse increases the risks of crossed contamination.
• soda lime eventually releases small quantities of CO 2, which had been previously absorbed, and the patient eventually inhales such quantities of CO 2 .
• the substitution process of said soda lime is relatively troublesome and time taking, since said reservoirs comprise two large chambers, which are individually filled in.
• - adjustable pressure limiting valves comprise a rigid element such as a hard disk or a pin acting over a air nozzle by means of a spring, wherein in said valves there is a direct contact between the exhaled gas and its internal parts, thus favoring the occurrence of contamination and eventual leakage through components intended to adjust pressure, also allowing the dispersion of the exhaled gas to the external environment, and the gas should be directed to the exhaust device.
• Another aspect of this kind of valve is the existence of dependence between the exhaust flow and the effective limited pressure, since due to the inertia of acting elements and the turbulence generated by the passage of gas flow through the rigid elements, when faster and sharper movements occur during manual ventilation, they eventually result in pressure peaks much above of set up values. In some applications, this kind of valve is inappropriate:
• CO 2 carbon dioxide
• Another object of the invention is to provide a CO 2 absorbing system comprising simple components and providing more safety and efficiency for both patients and professionals administering and controlling anesthesia. It is also another object of the invention to provide a CO 2 absorbing system comprising an appropriate and safe re-inhalation circuit that avoids eventual leakage or contamination.
• - Figure 1 shows a schematic diagram of the respiratory cycle of a device with CO 2 absorbing system provided with a re-inhalation circuit according to the present invention
• - Figure 2 shows a detailed perspective view of the CO 2 absorbing system set according to the present invention
• - Figures 3, 4 and 5 show, in different views, the manifold according to the present invention in a preferential embodiment of the CO 2 absorbing system showing the position of components which constitutes said manifold
• - Figures 6 and 7 show the inhalation and exhalation unidirectional valves, respectively, according to the present invention
• - Figures 8 and 9 show in details the passage of gas flow from the valves shown in Figures 6 and 7, respectively, in the open and closed positions
• - Figure 10 shows in
• FIG 1 shows a schematic diagram of the respiratory cycle of a respiratory device provided with a CO 2 absorbing system with a re-inhalation circuit of the present invention.
• the fresh gas coming from the anesthesia device (1 ) is introduced into the CO 2 absorbing system through the fresh gas inlet (2) and consequently into the respiration circuit of the patient.
• the gas is collected in a bag (3) or a bellows (4), depending on the application requirements, and according to the position of the selecting key (5) that determines the mode of operation of the device, manual or automatic, through a ventilator located within the anesthesia device (1 ).
• the bag (3) is filled in with gas so that the anesthesia physician or any other specialist may manually pump the gas to the patient.
• the gas flow passes through the soda lime reservoir (6), it is mixed with the fresh gas coming from the anesthesia device (1 ) and passes through the inhaling unidirectional valve (7), and then is conducted to the patient through an inhaling tube (8), thus filling in the patient's lung.
• the bag (3) is released from the pressure exerted by the specialist, the gas flow exhaled by the patient is conducted through the exhaling tube (9), passing through the exhaling unidirectional valve (10) and returning to said bag (3), and then the specialist re-starts the cycle by pressing the bag (3) again.
• the unidirectional valves (7) and (10) are to guide the gas flow during the patient's inhalation and exhalation in order to force the gas to pass through the soda lime reservoir (6) before re-inhalation of the patient.
• the CO 2 absorbing system of the present invention will comprise an adjustable pressure valve (11 ) that releases the gas excess produced in the respiratory cycle to the atmosphere through an appropriate exhaust system, since the fresh gas is continually introduced by the anesthesia device (1 ).
• the bellows (4) is filled with gas and pumping is done by means of a ventilator that pressurizes the internal side of a reservoir (12), in which said bellows (4) is located.
• the respiratory cycle occurs in the same way as disclosed above for the manual mode, but the adjustable pressure-limiting valve will not be activated, and the gas excess generated in the respiratory cycle will be controlled by an exhaust valve (13) of the ventilator itself. Said valve will allow the escaping of gas during exhalation as soon as the bellows is completely full, thus avoiding circuit pressurization beyond the previously set up value of the exhalation pressure.
• Concerning Figure 2 which shows in detail the CO 2 absorbing system, it is verified that it comprises a manifold (14) provided with an inhaling unidirectional valve (7), an exhaling unidirectional valve (10), an adjustable pressure limiting valve (11 ), a selective key (5) to select the operation mode, and a manual ventilation bag (3).
• the manifold (14) is also provided with an air inlet connection (15) to the bellows (4), with an exhaustion outlet (16) to take the excess of exhaled gases, with a re-inhalation tube (17), a telescopic base (18), a soda lime reservoir (6), and a condensate collector (19). All these components will be described below in more detail with reference to Figures 3 to 13.
• Figures 3, 4 and 5 show the position of the various components of the CO 2 absorbing system in a preferential embodiment of the manifold (14) according to the present invention.
• the Figures should not be interpreted in a limited way, since the various components incorporating said manifold (14) may be positioned in different places, as an men skill in the art should appreciate.
• the manifold (14) presents a relatively compact structure that results in a lighter and simpler structure due the position of the interconnections of the various components, such as those in the preferred embodiment of the present invention shown in Figures 3, 4 and 5.
• the manifold (14) incorporates inhaling (7) and exhaling (10) unidirectional valves, the selection key (5), the adjustable pressure limiting valve (11 ), the fresh gas inlet (20), the inlet connection of the oxygen sensor (48), the bag connection (21 ), the bellows connection (15), the exhaust outlet (16) to take the excess of anesthesia gases, and the quick fitting system of the soda lime reservoir (6) comprising the re-inhalation tube (17) and the telescopic base (18).
• inhaling (7) and exhaling (10) unidirectional valves are formed within the manifold body itself (14), so that the inlet channel (25) is provided with a base (22) where a flexible diaphragm (23) is fitted, settled and fixed at the center of said base (22).
• a cap (24), preferably of transparent material, is screwed into the body of the manifold (14) to hermetically close unidirectional valves (7), (10).
• Both unidirectional valves (7) and (10) differentiate between each other only by the placement of the inlet channels (25), which are previously defined upon the construction of the manifold (14).
• Figures 8 and 9 show in details the operation of the diaphragm, (23) which is preferably of silicone and comprises flexible rims (23a) and (23b) in the shape of butterfly wings, which are moved by action of the gas flow.
• the operation of unidirectional valves (7), (10) can be easily seen through transparent caps (24), which are preferably made of polysulphone or any other transparent and self-washable material. Caps are screwed to the body of the manifold (14) in order to allow easy and quick disassembly for eventual cleaning and substitution of said rims (23a), (23b).
• the unidirectional valves (7) and (10) of the present invention are immune to the effects caused by the humidity of exhaled gases, since the diaphragm (23) presents a surface of flexible material, and flexible rims (23a) and (23b) are fixed to the base (22) in order to present resilient effect towards closing. Therefore, they do not suffer from dragging effects, thus eliminating the risks of displacement and adherence of the diaphragm at the top of the valve, besides reducing the response time while the opening and closing of the flexible rims (23a), (23b). Therefore, both unidirectional valves can operate under high frequencies, e.g. up to 150 cycles/minute.
• the adjustable pressure limiting valve (11 ) is formed within the body of the manifold itself (14), being comprised by a flexible diaphragm (26), preferably of silicone, acting by means of a spring (28) over a air nozzle (27).
• Said diaphragm (26) is assembled in a cylindrical body (29) provided with a screw in which the adjustment button (30) is assembled. Therefore, by means of rotation of said adjustment button (30), it is possible to reach the control of spring (28) compression.
• FIG. 11 shows the soda lime reservoir (6) according to the present invention, which comprises two jars (31) joined by the respective bases by means of a flange (32), which in turn is provided with special fitting devices for said jars (31 ). Inside the jars (31 ), grids (33) are fitted, which openings obstruct the passage of soda lime grains and present low resistance to the flow of gas.
• Jar bases (31) are provided with placement channels (35) to place sealing rings (36), which are preferably of silicone, and also provided with fitting teeth (37) laterally distributed around the edges of said bases for coupling to the flange (32) fitting device, which is comprised by a grid (38), similar to those located inside the said jars, in order to forbid the passage of soda lime grains from one jar to the other one.
• Said flange (32) fitting device is formed by internal channels and tears (39) in which the respective fitting teeth (37) are settled and locked.
• Jars (31 ) are locked to the flange (32) by about 15° rotation of the jar towards the flange.
• jars (31 ) are identical and, just like the flange (32), are made of transparent and self-washable material. Polysulphone is preferred, but other embodiments may be developed.
• the reservoir is initially filled in through a jar (31 ) with the base turned upwards, subsequently fitting and locking the linking flange (32). This first set can be turned with the base below, since the grid (38) of the linking flange (32) inhibits the exit of soda lime grains.
• the second jar (31 ) is filled in, keeping the base above, and finally the first set, comprising the first jar and the flange, is fitted and locked to the other side of the linking flange (32).
• the useful volume capacity of the soda lime reservoir as described above is approximately 600 ml. This allows 4 to 6 hour autonomy in low flow anesthesia, therefore providing high re-inhalation grade.
• One of the great advantages provided by the soda lime reservoir according to the present invention is the fact that it can be previously filled in no matter which its assembly in the respiratory circuit is. That enables the preparation of various additional reservoirs to be available for use at any time, thus avoiding the soda lime change operation in the surgical environment during the course of anesthesia.
• the reservoir according to the present invention allows the use in newly born and pediatric patients, attempting to the appropriate selection of ventilation mode. Furthermore, a lower quantity of soda lime allows a more frequent substitution, preferably among patients, thus eliminating the risks of crossed contamination and CO 2 accumulation due to reservoir inactivity. Finally, the lower volume of soda lime also grants quicker balance between temperature and gas humidity inside the circuit.
• one of the main advantages of the circuit with re- inhalation is the use of low flows of fresh gas, since the anesthesia with low flow of fresh gas results in low consumption of anesthesia agents, besides providing reduction of environmental pollution and preservation of humidity and heat of the gas as exhaled by the patient.
• Such conditions are important to keep the control of anesthesia and the activity of ciliated mucous of the respiratory system, thus avoiding the mucous to become thick and the manifestation of athelectasies. Therefore, the reservoir according to the present invention, besides considerably reducing the time required for the filling with soda lime, as previously described, also presents a quick change device, which is better illustrated on Figure 12, thus causing less impact to the balance of the mix inside the circuit and consequently to the anesthesia control.
• the quick-change system comprises a manifold (14), a re-inhalation tube (17), and the telescopic base (18) provided with a return spring (40).
• the soda lime reservoir (6) assembled as described with reference to Figure 11 , presents at its end sealing rings (34) in the form of a cup.
• the assembly of the reservoir at the manifold (14) and, therefore, its connection to the respiratory circuit, is made by supporting one of the ends of the reservoir over the telescopic base (18), exerting pressure below, in order to win the force of the return spring (40) of the telescopic base and finally fitting the upper end of the reservoir to the recess (41 ) located at the manifold (14).
• the pressure of the return spring (40) is enough to return the telescopic base (18), support the weight of the reservoir (6) and press sealing rings (34) in the shape of a suction pad, thus assuring appropriate sealing to the CO 2 absorbing system of the present invention.
• the CO 2 absorbing system of the present invention has a collector (19) assembled at the lower end of the telescopic base (18). The collector (19) is better illustrated in Figure 13.
• Said collector (19) comprises a cup (42) to collect condensed water, which is fitted in a cap with a valve (43) provided with a male connection, which is fixed to the circuit by means of a "T" type connection (44), which connects the telescopic base (18) and the re-inhalation tube (17).
• a "T" type connection 44
• Said valve comprises an actuator (45) that by the action of a spring (46) closes the base in the said cap (43) of the collector (19).
• Said cup (42) has a pin (47) on its base that makes the dislocation of the actuator (45) when the cup is fitted, due the action of the said spring (46).

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• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Analytical Chemistry (AREA)
• General Chemical & Material Sciences (AREA)
• Oil, Petroleum & Natural Gas (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Gas Separation By Absorption (AREA)
• Pharmaceuticals Containing Other Organic And Inorganic Compounds (AREA)
• Respiratory Apparatuses And Protective Means (AREA)

Applications Claiming Priority (2)

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ID=34578391

Family Applications (1)

Country Status (2)

Cited By (3)

Citations (11)

• 2003
  • 2003-11-17 BR BRPI0305789-5B1A patent/BR0305789B1/pt not_active IP Right Cessation
• 2004
  • 2004-08-04 WO PCT/BR2004/000143 patent/WO2005046843A1/en active Application Filing

Patent Citations (11)

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