PULMONARY VENTILATOR WITH CHANGEABLE FILTERS
20210023325 ยท 2021-01-28
Inventors
Cpc classification
A61M2205/7581
HUMAN NECESSITIES
A61M2205/0205
HUMAN NECESSITIES
A61M16/1045
HUMAN NECESSITIES
A61M16/208
HUMAN NECESSITIES
A61M16/024
HUMAN NECESSITIES
International classification
A61M16/08
HUMAN NECESSITIES
Abstract
In a pulmonary ventilation system, a filter arrangement useful as an input filter arrangement and an output filter arrangement is constructed to allow for changing or cleaning of the filter without interrupting or impacting the ventilation therapy and to limit the release of pathogens to the surrounding area or atmosphere. A preferred exhaust filter is constructed to function as a water trap and filter. Methods of operating the pulmonary ventilation system are also disclosed along with kits containing materials to construct an input or an output filtration structure.
Claims
1. A pulmonary ventilator system for transmitting a breathable gas formed of a first gas and a second gas different from said first gas into an input and output device for insertion into the trachea of a patient wherein said breathable gas upon discharge from said patient through said input and output device becomes an exhaust gas with pathogens from said patient, said pulmonary ventilator system comprising: a ventilator configured to receive said first gas and said second gas, to blend said first gas and said second gas to form blended gas, and to supply said blended gas at a ventilator output; a first supply line connectable to said ventilator output for receiving said blended gas; input filtration connected to receive said blended gas from said first supply line, said input filtration including an inlet filter to filter said blended gas to form breathable gas, a second supply line connectable to receive said breathable gas from said input filtration and supply said breathable gas through said input and output device to the trachea of said patient; an exhaust line having a first end connectable to said input and output device for receiving said exhaust gas with said pathogens from said patient, and a second end spaced from said first end; exhaust filtration structure for filtering said pathogens from said exhaust gas to form filtered exhaust gas, said exhaust filtration structure having an inlet connected to receive said exhaust gas with said pathogens from said second end of said exhaust line, said exhaust filtration structure being formed to be configurable to have a first path for said exhaust gas with pathogens and a second path for said exhaust gas with pathogen, said exhaust filtration structure having a first filter positionable in said first path to receive said exhaust gas with said pathogens from said inlet to filter said exhaust gas and to form first filtered exhaust gas, and said exhaust filtration structure having a second filter positionable in said second path to receive said exhaust gas with said pathogens from said inlet to filter said exhaust gas with said pathogens to form second filtered exhaust gas; a system outlet connected to receive said first filtered exhaust gas and said second filtered exhaust gas to become outlet gas and to transmit said outlet gas; an exhaust valve associated with said ventilator and connected to receive said outlet gas, said exhaust valve being controllable to periodically discharge said outlet gas to the atmosphere to regulate the flow of breathable gas.
2. The pulmonary ventilation system of claim 1 wherein said exhaust filtration structure has a first filter in said first path, said first filter having, a housing that has a first wall having a first wall aperture formed therethrough, and a second wall spaced from said first wall, said second wall having a second wall aperture formed therethrough, said housing having a housing top and a housing bottom assembled with said first wall and said second wall to define a housing volume having a first open end and a second open end opposite said first open end, a housing inlet attached to said first wall and connectable to said second end of said exhaust line, said housing inlet having an inlet channel in registration with said first wall aperture to receive said exhaust gas with said pathogens to form a first portion of said first path; a housing outlet having an outlet channel in registration with said second wall aperture, said housing outlet being connected to said second wall, a first cartridge having a first cartridge wall, having a second cartridge wall spaced from said first cartridge wall, having a plurality of first cartridge sides, said plurality of first cartridge sides, said first cartridge wall and said second cartridge wall all being assembled to define a first cartridge volume, said first cartridge being shaped and sized to slide into said housing volume through one of said first open end and said second open end of said housing, said first cartridge wall having a first cartridge aperture formed therein in to be in registration with said first wall aperture when said first cartridge is positioned in said housing volume, said second cartridge wall having a second cartridge aperture formed therein to be in registration with said second wall aperture when first cartridge is positioned in said housing volume, having first filter media to filter said pathogens in said gas having pathogens and positioned in said first cartridge volume, said first cartridge being positionable in said first housing volume to form a second portion of said first path for the transmission of said exhaust gas with said pathogens from said first wall aperture to said first cartridge aperture, through said filter media, through said second cartridge aperture to said second wall aperture and to said outlet channel, said filtered exhaust gas becoming outlet gas directed though said outlet to said exhaust valve; a second filter in said second path, said second filter comprising said housing having said inlet channel in registration with said first wall aperture and formed to receive said exhaust gas with said pathogens to form a first portion of said second path and communicate said exhaust gas with said pathogens through said inlet channel and said first wall aperture, a second cartridge having a third cartridge wall having a third cartridge wall aperture formed therein a fourth cartridge wall spaced from said first cartridge wall, said fourth cartridge wall having a fourth cartridge wall aperture formed therein, a plurality of second cartridge sides along with said third cartridge wall and said fourth cartridge wall, all assembled to define a second cartridge volume, said second cartridge being shaped and sized to sealingly slide into said first housing volume through one of said first open end and said second open end of said housing to displace said first cartridge from said first cartridge volume, second filter media to filter said pathogens in said exhaust gas having pathogens positioned in said second cartridge volume, said second cartridge being positionable in said housing volume between said first wall aperture and said second wall aperture to form a second portion of said first path for the transmission of said exhaust gas with said pathogens from said first wall aperture to said third cartridge wall aperture, through said filter media and said fourth cartridge wall aperture to form second filtered exhaust gas directed though said second wall aperture to said second outlet to become outlet gas; and seal means associated with one of said housing and one of said first cartridge and said second cartridge for effecting a seal to inhibit leakage of said exhaust gas with pathogens from and between said first housing aperture and said first cartridge aperture or between said first housing aperture and said third cartridge aperture and to in inhibit leakage of filtered exhaust gas from and between said second cartridge aperture and said second wall aperture or to inhibit leakage of said filtered exhaust gas from and between said fourth cartridge aperture and said second wall aperture.
3. The pulmonary ventilation system of claim 2 further including registering means associated with one of and both of said housing and said first cartridge for holding said first cartridge in said housing with the first cartridge aperture in registration with said first housing aperture and said second cartridge aperture in registration with said second housing aperture.
4. The pulmonary ventilation system of claim 2 wherein said plurality of first cartridge sides includes a first front and a second front spaced from and opposite said first front, wherein said plurality of second cartridge sides includes a third front and a fourth front spaced from and opposite said third front, wherein said seal means includes a first cartridge seal attached to said first cartridge wall, said second cartridge wall, said first front and said second front, and wherein said seal means further includes a second cartridge seal attached to said third cartridge wall, said fourth cartridge wall, said third front and said fourth front.
5. The pulmonary ventilation system of claim 2 wherein said first filter cartridge has a first cartridge length and said housing has a housing length, and wherein said first cartridge length is less than the housing length.
6. The pulmonary ventilation system of claim 2 wherein said housing has a length and wherein said housing top is formed in the shape of a housing top slot which extends the length of said housing, wherein said housing has a bottom formed in the shape of a housing bottom slot which extends the length of said housing, wherein said first cartridge has a cartridge top formed in the shape of a first cartridge top ridge sized to register and slide in said housing top slot, wherein said first cartridge has a bottom formed in the shape of a first cartridge bottom ridge to register with and slide in said housing bottom slot.
7. The pulmonary ventilation system of claim 7 wherein said housing top slot has a plurality of notches formed through and along said length of said housing to form a ratchet structure; and wherein the first cartridge ridge has a pawl oriented at an angle to engage each of said plurality of notches when said first cartridge is being urged into said housing volume.
8. The pulmonary ventilation system of claim 6 wherein said first cartridge bottom ridge has an arm portion that deflects toward and away from said first wall, said arm portion having a raised portion thereon, and wherein said housing bottom slot has an opening to register with said raised portion when said first cartridge is positioned in said housing volume and said first wall aperture is in registration with said first cartridge aperture.
9. The pulmonary ventilation system of claim 4 wherein said first cartridge aperture has a first cartridge grid thereon and wherein said second cartridge aperture has a second cartridge grid thereon.
10. The pulmonary ventilation system of claim 2 further including a coupling having a first connector and a second connector that interact to removably connect one to the other but when connected inhibit separation of said first connector and said second connector and wherein said first cartridge has a first connector of said coupling attached to one of said first front and said second front of said first cartridge, and wherein said second connecter of said coupling is attached to one of said third front and said fourth front of said second cartridge for connecting to said first connector to inhibit movement of said first cartridge relative to said second cartridge.
11. The pulmonary ventilation system of claim 1 wherein said exhaust filtration structure further comprises an inlet connected to receive said exhaust gas with said pathogens from said second end of said exhaust line, a first conduit to receive said exhaust gas with said pathogens from said inlet; a valve connected to receive said exhaust gas from said conduit, said valve being operable between a first position to direct said exhaust gas with said pathogens through a first path and a second position to direct said exhaust gas with said pathogens through a second path. a first filter in said first path for filtering said pathogens from said exhaust gas with said pathogens to form first filtered exhaust gas; a second filter in said second path for filtering said pathogens from said exhaust gas with said pathogens to form second filtered exhaust gas; a second conduit connected to receive said first filtered gas and said second filtered gas and supply same as outlet gas; a first check valve in said first path operable between an open position in which said first filtered gas passes therethrough and a closed position in which said first check valve is in a closed position to inhibit the flow of said second filtered gas therethrough; a second check valve in said second path operable between an open position in which said second filtered gas passes therethrough and a closed position in which the second check valve inhibits the flow of said first filtered gas therethrough; an outlet configured to receive said first filtered exhaust gas and said second filtered exhaust gas to become outlet gas and supply said outlet gas; an exhaust valve included in said ventilator and connected to receive said exhaust gas, said exhaust valve being operable to discharge said outlet gas to the atmosphere to maintain pulmonary therapy.
12. The pulmonary ventilator system of claim 1 wherein said first filter has a filter element and a filter element holder configured to hold said filter element, and wherein said filter element holder is operable between an inserted position wherein said filter element is in said first path and a second position wherein the said filter element is removed from said first path to form said second path, said filter element being removable from said filter element holder.
13. The pulmonary ventilator system of claim 1 wherein said exhaust gas includes moisture from said patient and wherein said exhaust filtration structure includes a water trap connected in said first conduit to remove moisture from said exhaust gas.
14. The pulmonary ventilation system of claim 1 wherein said input filtration includes a humidifier to humidify the filtered blended gas.
15. The pulmonary ventilation system of claim 1 including an Y connector having one leg connected to receive said breathable gas, a second leg to communicate said exhaust gas with said pathogens from said patient and a third leg connected to an HME filter and then to said input and output device.
16. A pulmonary ventilator system for transmitting a breathable gas formed of a first gas a second gas different from said first gas into the trachea of a patient through an input and output device wherein said breathable gas is converted in said patient to an exhaust gas with pathogens obtained from said patient, said input and output device being configured for transmitting said exhaust gas with said pathogens from said trachea, said pulmonary ventilator system comprising: a ventilator configured to receive and blend said first gas and said second gas to form blended gas, and supply said blended gas at a ventilator output; a first supply line connectable to said ventilator output for receiving said blended gas; input filtration connected to receive said blended gas from said first supply line and to supply breathable gas, said input filtration including a filter to filter said blended gas, and a second supply line connectable to receive said breathable gas from said input filtration and supply said breathable gas through said input and output device to said patient; an exhaust line having a first end connectable to said input and output device for receiving said exhaust gas with said pathogens from said patient, and a second end spaced from said first end; exhaust filtration structure for filtering said pathogens from said exhaust gas to form filtered exhaust gas, said exhaust filtration structure having an inlet connected to receive said exhaust gas with said pathogens from said second end of said exhaust line, a first conduit to receive said exhaust gas with said pathogens from said inlet, a first filter for filtering said pathogens from said exhaust gas with said pathogens to form first filtered exhaust gas, a second filter for filtering said pathogens from said exhaust gas with said pathogens to form second filtered exhaust gas, a valve arrangement connected to receive said exhaust gas from said conduit and to supply said exhaust gas with said pathogens to said first filter and to said second filter, said valve arrangement being operable between a first configuration directing said exhaust gas with said pathogens in a first path to said first filter and not said second filter and a second configuration directing said exhaust gas with said pathogens in a second path to said second filter and not said first filter, an outlet configured to receive said first filtered exhaust gas from said first path and said second filtered gas from said second path to form outlet gas; a first check valve positioned in said first path, said first check valve being open to pass said first filtered gas to said out and closed to inhibit the flow of second filtered gas therethrough; a second check valve positioned in said second path, said second check valve being open to pass said second filtered gas to said outlet and closed to inhibit the flow of first filtered gas therethrough; and an exhaust valve associated with said ventilator connected to receive said outlet gas and operable to supply said outlet gas to the atmosphere, said exhaust valve being controllable to periodically discharge said outlet gas to the atmosphere to regulate the flow of breathable gas.
17. The pulmonary ventilator system of claim 16 wherein said exhaust gas with pathogens includes moisture from said patient and wherein said filtration structure further includes a water trap positioned to filter said moisture from said exhaust gas.
18. The pulmonary ventilation system of claim 16 further including a housing having a housing inlet connectable to said second end of said exhaust line and an housing outlet connectable to said exhaust valve, said housing having a first chamber in communication with said inlet to receive exhaust gas with said pathogens therefrom, and wherein said valve arrangement is positioned in said first chamber, wherein said housing has a second chamber and a third chamber with said valve arrangement operable to direct said exhaust gas with said pathogens in said first position to said second chamber and in said second position to said third chamber, and wherein a first insert is configured to snuggly and removably position in said second chamber, and wherein a second insert configured to snuggly and removably position in said third chamber, said first insert including said first filter and said second insert including said second filter.
19. The pulmonary ventilation system of claim 18 wherein said first chamber has a first outlet in communication with said first check valve and wherein said second chamber has a second outlet in communication with said second check valve.
20. The pulmonary ventilation system of claim 18 wherein said valve arrangement has a lever external to said housing sized for operation by a user to move said valve between said first position and said second position.
21. A method for filtering the exhaust gas in a pulmonary ventilator system configured to transmit a breathable gas formed from two different breathable gases to and from a patient through an input and output structure configured for introduction of said breathable gas into the trachea of said patient, said breathable gas obtaining pathogens from said patient, and said input and output structure being further configured for transmitting said breathable gas with said pathogens from said trachea through said input and output structure to form said exhaust gas with pathogens, said method for filtering said exhaust gas comprising: providing an exhaust line having a first end connectable to said input and output structure for receiving said exhaust gas with said pathogens from said input and output structure, a second end spaced from said first end, and a stretch extending between said first end and said second end for communicating said exhaust gas with said pathogens from said first end to said second end; exhaust filtration structure for filtering said pathogens from said exhaust gas to form filtered exhaust gas, said exhaust filtration structure having an inlet connected to receive said exhaust gas from said second end of said exhaust line, an outlet configured to supply said filtered exhaust gas from said exhaust filtration structure, a first conduit for the movement of said exhaust gas from said inlet to a filter means, a second conduit for the movement of filtered exhaust gas to said outlet, said filter means connectable to receive said exhaust gas from said inlet, said filter means being configured to filter said pathogens from said exhaust gas to form filtered exhaust gas, said filter means having a filter housing having a movable filter holder for holding a first filter element, said movable filter holder being movable between a first position in which said filter holder is positionable in said filter housing to position said first filter element to filter said exhaust gas to remove said pathogens therefrom to form said filtered exhaust gas, and a second position where said movable filter holder is positioned relative to said filter housing to direct the exhaust gas from said first conduit to said second conduit while said filter holder is positioned for removal of said first filter element; providing a discharge line having a first end and a second end, said first end being connectable to said outlet of said exhaust filtration structure to receive said exhaust gas when said filter holder is in said second position and to receive said filtered exhaust gas when said filter holder is in said first position; providing a second filter element comparable to said first filter element; operating said filter means to position said filter holder in said second position; removing said first filter element from said filter holder; placing said second filter element in said filter holder; and operating said filter means to position said filter holder in said first position. connectable to said outlet of said port to receive said filtered exhaust.
22. A method for filtering the exhaust gas in a pulmonary ventilator system configured to transmit a breathable gas to and from a patient through an endotracheal tube for introduction of said breathable gas into the trachea of said patient, said breathable gas obtaining pathogens from said patient, and said endotracheal tube being further configured for transmitting said breathable gas with said pathogens from said trachea through said input and output structure to form said exhaust gas with said pathogens, said method for filtering said exhaust gas comprising: providing an exhaust line having a first end connectable to said input and output structure for receiving said exhaust gas with said pathogens from said input and output structure, a second end spaced from said first end, and a stretch extending between said first end and said second end for communicating said exhaust gas with said pathogens from said first end to said second end; exhaust filtration structure for filtering said pathogens from said exhaust gas to form filtered exhaust gas, said exhaust filtration structure having an inlet connectable to receive said exhaust gas from said second end of said exhaust line, an outlet configured to supply said filtered exhaust gas from said exhaust filtration structure, said filter means connectable to receive said exhaust gas with pathogens from said inlet, said filter means being configured to filter said pathogens from said exhaust gas to form filtered exhaust gas, said filter means having a first leg connected to receive said exhaust gas with pathogens, a first filter connected to said first leg to receive exhaust gas with said pathogens, a second leg connected to receive exhaust gas with said pathogens, a second filter connected to receive said exhaust gas with said pathogens, a valve connected to said inlet to receive said exhaust gas with said pathogens and to said first leg and to said second leg, said valve being operable between a first position in which said exhaust gas with said pathogens is directed to said first leg and a second position in which said exhaust gas with said pathogens is directed to said second leg, a third leg connected from said first filter to said outlet, and a fourth leg connected from said second filter to said outlet, providing a discharge line having a first end and a second end, said first end being connectable to said outlet of said exhaust filtration structure to receive said exhaust gas when said filter holder is in said second position and to receive said filtered exhaust gas when said filter holder is in said first position; connecting said exhaust line to said endotracheal tube; connecting said exhaust filtration structure to said exhaust line; connecting said third and fourth leg to said discharge operating said valve to said first position to direct said exhaust gas with said pathogens therethrough to filter said pathogens to form filtered exhaust gas; operating said valve to said second position to direct said exhaust gas with said pathogens to filter said pathogens to form filtered exhaust gas; disconnecting said first filter from said first leg and said third leg and removing same; inserting a new filter to function as said first filter; operating said valve to said first position to direct said exhaust gas with said pathogens through said new filter to form filtered exhaust gas.
23. For use in a pulmonary ventilator system for transmitting a breathable gas to a patient through an input and output structure configured for introduction of said breathable gas into the trachea of said patient wherein said breathable gas in said patient becomes an exhaust gas with pathogens obtained from said patient, said input and output structure being configured for transmitting said exhaust gas with said pathogens from said trachea, a changeable filter system comprising: a first filter to remove said pathogens to form first filtered exhaust gas; a second filter to remove said pathogens to form second filtered exhaust gas; a valve connectable to said exhaust line to receive said exhaust gas from said input and output structure, said valve being configured and connected to direct said exhaust gas to flow either in a first path through said first filter device or a second path through said second filter device; and a discharge line having a first end and a second end, said first end being connectable to receive said first filtered exhaust gas and to receive said second filtered exhaust gas, said discharge line being configured to direct the first filtered exhaust gas and the second filtered exhaust gas to said second end.
24. For use in a pulmonary ventilator system having a ventilator for blending two gases one of which may contain pathogens to form blended gas and to pass through an inlet filter to become a breathable gas supplied to a patient through an input and output structure configured for introduction of said breathable gas into the trachea of said patient wherein said breathable gas in said patient becomes an exhaust gas with pathogens obtained from said patient which are passed through and outlet filter, said input and output structure being configured for transmitting said exhaust gas with said pathogens from said trachea, a changeable filter to filter the blended gas and the exhaust gas comprising: a first filter configured to receive said blended gas from said ventilator to remove pathogens therefrom to form first breathable gas; a second filter configured to receive said blended gas from said ventilator to remove said pathogens therefrom to form second breathable gas; a valve connectable to receive said blended gas from ventilator, said valve being operable between a first position to direct said blended gas in a first path to and through said first filter and a second position to direct said blended gas in a second path to and through said second filter; a first outlet line connected to said first filter to receive said first breathable gas therefrom; a second outlet line connected to said second filter to receive said second breathable gas therefrom; a discharge line having a first end and a second end, said first end being connectable to said first outlet line to receive said first breathable gas and connectable to said second outlet line to receive said second breathable gas, said discharge line being configured to direct the first breathable gas and the second breathable gas to said second end to form breathable gas for supply to said patient; a first check valve positioned in said first outlet line operable to allow said first breathable gas therethrough and to inhibit the movement of said second breathable gas therepast; and a second check valve positioned in said second outlet line operable to allow said second breathable gas therethrough and to inhibit the movement of said first breathable gas therethrough.
25. For use in a pulmonary ventilator system having a ventilator for blending two gases one of which may contain pathogens to form blended gas to become a breathable gas supplied to a patient through an input and output structure configured for introduction of said breathable gas into the trachea of said patient wherein said breathable gas in said patient becomes an exhaust gas with pathogens obtained from said patient, said input and output structure being configured for transmitting said exhaust gas with said pathogens from said trachea, a changeable inlet filter comprising: a first filter configured to receive said blended gas from said ventilator to remove pathogens therefrom to form first breathable gas; a second filter configured to receive said blended gas from said ventilator to remove said pathogens therefrom to form second breathable gas; a valve connectable to receive said blended gas from ventilator, said valve being operable between a first position to direct said blended gas in a first path to and through said first filter and a second position to direct said blended gas in a second path to and through said second filter; a first outlet line connected to said first filter to receive said first breathable gas therefrom; a second outlet line connected to said second filter to receive said second breathable gas therefrom; a discharge line having a first end and a second end, said first end being connectable to said first outlet line to receive said first breathable gas and connectable to said second outlet line to receive said second breathable gas, said discharge line being configured to direct the first breathable gas and the second breathable gas to said second end to form breathable gas for supply to said patient; a first check valve positioned in said first outlet line operable to allow said first breathable gas therethrough and to inhibit the movement of said second breathable gas therepast; and a second check valve positioned in said second outlet line operable to allow said second breathable gas therethrough and to inhibit the movement of said first breathable gas therethrough.
26. A filter system comprising: a housing having an first housing wall with a first wall aperture therein and a second housing wall with a second wall aperture therein, said housing having a plurality of housing sides assembled with said first housing wall and said second housing wall to define a housing volume with a first open end and a second open end opposite said first open end, and said housing having a housing length extending between said first open end and said second open end; an inlet having an inlet channel formed therein, said inlet being configured to receive into said inlet channel a gas having pathogens, said inlet being attached to said first housing wall with said inlet channel aligned with said first wall aperture for the passage; an outlet having an outlet channel formed therein, said outlet being attached to said second housing wall with said outlet channel aligned with said second wall aperture to be in communication with said housing volume; a first cartridge having a first cartridge wall, a second cartridge wall spaced from said first cartridge wall, and a plurality of first cartridge sides all assembled to define a first cartridge volume, and said first cartridge, said first cartridge being shaped and sized to slide into one of said first open end and said second open end of said housing; said first cartridge wall having a first cartridge aperture formed therein; said second cartridge wall having a second cartridge aperture formed therein, and first filter media to filter said pathogens in said gas having pathogens and positioned in said volume; seal means associated with one of said housing and said first cartridge for effecting a seal to prevent leakage of said gas with pathogens from between said first wall aperture and said first cartridge aperture and between said second wall aperture and said second cartridge aperture; and registering means associated with one of and both of said housing and said first cartridge for holding said first cartridge in said housing with the first cartridge aperture in registration with said first wall aperture and said second cartridge aperture in registration with said second wall aperture.
27. The filter of claim 26 wherein said housing has a housing top and a housing bottom each formed into slots with said first cartridge having a first cartridge top and a first cartridge bottom formed into ridges sized to register and slide into said slots of said housing bottom and said housing top, and wherein said first cartridge has a length and one of said first cartridge top and said first cartage bottom has housing top and bottom has deflectable lever formed therein with a raised element thereon, and wherein said a corresponding one of first housing top and said first housing bottom has an aperture formed therein to register with said raised element which is urged into said aperture by said deflectable lever.
28. The filter of claim 26 wherein said housing is formed of two identical halves sealed together.
29. A filter system comprising: a housing having an first housing wall with a first wall aperture therein and a second wall with a second wall aperture therein, said housing having a plurality of housing sides assembled with said first housing wall and said second housing wall to define a housing volume with a first open end and a second open end opposite said first open end; an inlet having an inlet channel formed therein, said inlet being configured to receive into said inlet channel a gas having pathogens, said inlet being attached to said first housing wall with said inlet channel aligned with said first aperture for the passage of said gas having pathogens; an outlet having an outlet channel formed therein, said outlet being attached to said second housing wall with said outlet channel aligned with said second aperture to be in communication with said volume; a first cartridge having a first cartridge wall, a second cartridge wall spaced from said first cartridge wall, and a plurality of first cartridge sides all assembled to define a first cartridge volume, said first cartridge being shaped and sized to slide into one of said first open end and said second open end of said housing and into said housing volume, said first cartridge wall having a first cartridge aperture formed therein, said second cartridge wall having a second cartridge aperture formed therein, and first filter media to filter said pathogens in said gas having pathogens and positioned in said volume; registering means associated with one of and both of said housing and said first cartridge for moveably holding said first cartridge in said housing with the first cartridge aperture in registration with said first housing aperture and said second cartridge aperture in registration with said second housing aperture; a second cartridge having a third cartridge wall, a fourth cartridge wall spaced from said first cartridge wall, and a plurality of second cartridge sides all assembled to define a second cartridge volume, said second cartridge being shaped and sized to slide into one of said first open end and said second open end of said housing to abut and displace said first cartridge, said third cartridge wall having a third cartridge aperture formed therein, said fourth cartridge wall having a fourth cartridge aperture formed therein, and second filter media to filter said pathogens in said gas having pathogens and positioned in said volume; seal means associated with one of said housing and said first cartridge and said second cartridge for effecting a seal to prevent leakage of said gas with pathogens from between said first wall aperture and said first cartridge aperture and between said second wall aperture and said second cartridge aperture and for effecting a seal to prevent leakage of said gas with pathogens from between said first wall aperture and said third cartridge aperture and between said second wall aperture and said fourth housing aperture; registering means associated with one of and both of said housing and said first cartridge and said second cartridge for moveably holding said first cartridge in said housing with the first cartridge aperture in registration with said first wall aperture and said second cartridge aperture in registration with said second wall aperture and for holding said second cartridge in said housing with the third cartridge aperture in registration with said first wall aperture and said fourth cartridge aperture in registration with said second wall aperture.
30. The filter of claim 29 wherein the length of the first filter cartridge is less than the length of the housing.
31. The filter of claim 29 wherein the plurality of first cartridge sides of the first cartridge includes a first cartridge front and a first cartridge back, and wherein said seal means includes a sealing material is wrapped around and adhered to the first cartridge wall the second cartridge wall, first cartridge front and the first cartridge back and wherein the plurality of second cartridge sides of the second cartridge includes a second cartridge front and a second cartridge back, and wherein said seal means includes a sealing material is wrapped around and adhered to the third cartridge wall, the fourth cartridge wall, second cartridge front and second cartridge back.
32. The filter of claim 29 wherein said housing has a housing top formed in the shape of a housing top slot which extends the length of said housing, wherein said housing has a bottom formed in the shape of a housing bottom slot which extends the length of said housing, wherein said first cartridge has a cartridge top formed in the shape of a first cartridge top ridge sized to register and slide in the housing top slot, wherein said first cartridge has a bottom formed in the shape of a first cartridge bottom ridge to register with and slide in the housing bottom.
33. The filter of claim 36 wherein said housing top slot has a plurality of notches with openings formed therein along the length of said housing slot to be a ratchet; where the first cartridge ridge has a pawl along said cartridge slot positioned to engage each notch when being urged into said housing volume.
34. The filter of claim 29 wherein said first cartridge bottom ridge has a deflectable portion that deflects toward and away from said first wall, said lever portion having a raised portion thereon, and wherein said housing bottom slot has an opening to register with said raised portion when said first cartridge is positioned in said housing volume with said first wall aperture in registration with said first cartridge aperture.
35. The filter of claim 29 wherein said first cartridge aperture has a first cartridge grid thereon and wherein said second cartridge aperture has a second cartridge grid thereon.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0030] To further clarify the advantages and features of the systems and structure herein disclosed, a more particular description is rendered with reference to the appended drawings. It should be understood that the drawings depict only typical embodiments and therefore are not to be considered limiting of the scope of the appended claims. More specifically:
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DESCRIPTION
[0062] Hospitals, clinics, infirmaries, immediate or urgent care facilities and even medical offices of doctors and other medical practitioners may have patients visiting such places that carry pathogens exposing the treating medical practitioners and their related staffs (e.g., nurses, nurses aids, orderlies, nurse practitioners, administrators and other care givers) to those pathogens (e.g., a bacterium or bacteria as well as a virus such as COVID 19 or other microorganism that can cause disease). Efforts are being made to reduce the presence and/or spread of such pathogens in all locations using a wide variety of products, practices and procedures (e.g., widespread and frequent cleaning, hand washing, use of face masks, use of surgical gloves and gowns, use of disinfectants and the like).
[0063] To reduce the spread of pathogens in locations where patients receive pulmonary respiration or ventilation therapy, the exhaust of the pulmonary ventilation system (e.g., the exhaled breath from the infected patient) may be filtered to reduce the discharge of pathogens from the patient to the atmosphere as recommended by at least the CDC. That is, a filter may be placed in the exhaust limb or exhaust circuit of a pulmonary or respiratory therapy system; and then the filter is changed from time to time consistent with recommendations of agencies such as the CDC. Nevertheless, in known systems, the exhaust gas from the patient is vented directly into the environment of the patient at a location where the pulmonary respiration or ventilation therapy is being administered as the exhaust limb or exhaust circuit or line is opened up to remove and replace or clean the filter in the exhaust limb or exhaust circuit. When the exhaust circuit or limb is opened and the filter in the exhaust circuit or limb is removed, the exhaust gas vents directly to the nearby environment. The amount of exhaust gas that is released to the environment increases with the frequency of filter change (or cleaning) and the amount of time taken to complete the filter change or filter cleaning.
[0064] As stated hereinbefore, pulmonary ventilation systems are used to provide patients with pulmonary respiration or ventilation therapy in the form of breathable gas. The gas is typically a mixture of air and oxygen. The patient receives the breathable gas typically through an input and output structure such as an endotracheal tube that is inserted through the mouth into the trachea of the patient. The breathable gas may also be inserted using tubing directly inserted into the trachea following a tracheotomy procedure. The input and output structure may also be in the form of an oxygen mask that typically covers the nose and mouth. The breathable gas is inspirated as breathable gas and then expirated through the input and output structure such as the endotracheal tube as exhaust gas with pathogens and also with moisture from the patient entrained. That is, the pulmonary ventilation system has an exhaust limb or circuit to take the exhaust gas away from the patient through exhaust filtration structure to an exhaust valve (associated with a ventilator) which operates in accordance with control input from the ventilator control to maintain a virtually uninterrupted flow of breathable gas and avoid loss of FRC.
[0065] Also, as hereinbefore stated, the exhaust filtration limbs or circuits typically have a water trap to remove the moisture in the exhaust gas and a filter to remove pathogens from the gas. Water traps typically have a valve associated with them to facilitate removal. However, it is believed that cleaning or replacing the filter involves breaking the exhaust circuit and venting the exhaust gas with any pathogens therein to the atmosphere while the filter is being cleaned or a new or replacement filter or filter element installed. Systems and filter arrangements described hereinafter operate to minimize and preferably eliminate the release of exhaust gas with pathogens and the release of moisture to the atmosphere during the cleaning or changing of the filter and/or filter element in the exhaust limb or circuit.
[0066] The exhaust filtration structure disclosed herein may also include a filter and water trap combination. That is, a new valve structure includes the combination of a water trap feature and a filter structure along with a valve combined and used in a system to maintain ventilation while servicing the filter or water trap and to preclude or reduce the release of exhaust gas with pathogens to the environment surrounding the patient. Also disclosed is a kit the contents of which are to be used to form an exhaust filter structure for use with a pulmonary ventilation system which reduces the release of exhaust gas with pathogens to the environment.
[0067] A new pulmonary ventilation system here disclosed in
[0068] The new pulmonary ventilation system 35 of
[0069] As seen in
[0070] In operation, it can be seen that the valve 66 is operable between a first position 84 (shown in solid line in
[0071] With the valve 66 oriented in the second position (seen in dotted line in
[0072] As noted, the inlet ventilation system 35 disclosed also has input filtration 9A that includes changeable inlet filter 450 depicted in
[0073] After the blended gas 15 is filtered in the first filter 462 to remove contaminants including pathogens to produce first filtered gas 466, the first filtered gas 466 then proceeds to an outlet line 468 through a first check valve 478 discussed hereinafter and then a first filter leg 464. The outlet line 468 is connected to second supply line 41 for further connection to the input and output structure 42. A portion of the first filtered gas 466 may also proceed backward (shown in dotted line) through second filter leg 472 toward filter 2 or the second filter 470 when the valve 456 is in the first position 458 and the second filter 470 is removed for disposal and replacement with a new (clean) filter or removed for cleaning if it is of the type or kind that can be cleaned. With the second filter 470 removed, the first filtered gas 466 may exit to the atmosphere directly from the second filter leg 472 if there is no second check valve 476. If there is a second check valve 476 in the system, it will be configured to stop the flow of first filtered gas 466 therethrough so that all of the first filtered gas 466 proceeds to the outlet 468. The second check valve 476 is shown in the closed position in solid and an open position in dotted line.
[0074] When the valve 456 is in the second position 460 shown in dotted line, the blended gas 15 proceeds to the filter 2 or second filter 470 where the blended gas 15 is filtered to remove pathogens and any other unwanted material to form second filtered gas 474 which proceeds to the outlet 468 for further transmission. A portion of the second filtered gas 474 may also proceed as shown in dotted line through the first filter leg 464 when the first filter 462 is removed so it can be replaced or cleaned. Of course to stop the escape of second filtered gas 474 with the first filter 462 removed the first check valve 478 functions to close so that a portion of the second filtered gas 474 cannot escape there past and all will be directed to the outlet 468.
[0075] The use of first check valve 478 and second check valve 476 is preferable for the changeable inlet filter 450 as the flow of breathable gas 11 to the patient will not be interrupted or changed when an inlet filter such as first inlet filter 462 or the second inlet filter 470 is being changed. Thus the FRC remains unaffected. That is, the ventilation therapy is not then interrupted or modified as second filtered gas 474 does not vent or escape. Use of a system such as that illustrated in
[0076] In operation, the changeable inlet filter 450 can operate through one filter like first filter 462 with the valve 456 in a first position 458 until first filter 462 becomes contaminated. When the valve 456 is in the first position 458, the second filter 470 can be removed and replaced with a new and clean filter or cleaned. The valve 456 may then be moved to the other or second position 460 directing the blended gas to the second filter 470 so that the first filter 462 can be removed and replaced with a new filter or cleaned. Inasmuch as the first filter 462 and the second filter 470 are of the same size and type as are the replacements, the supply of breathable gas 11 remains essentially unchanged and of suitable or desired quality.
[0077] Turning now to
[0078] As depicted best in the exploded view of
[0079] The port 100 has an inlet 102 to receive exhaust gas 13 and direct it through the cup 92 and filter membrane 184 to the outlet 104 to supply filtered exhaust gas in a first configuration. In a second configuration, the exhaust gas 13 as received in the inlet 102 is directed straight to the outlet 104, all as discussed hereinafter. The port 100 has a top 106 and a side 108. As seen, the side 108 is circular in projection while the top 106 is essentially planar.
[0080] As best seen in
[0081] It may also be noted that the inlet 102 has an outside diameter 124 and an inside diameter 126 both sized to receive typical flexible tubing used in pulmonary ventilation systems. Similarly, the outlet 104 has an outside diameter 125 and an inside diameter 164. Both the inlet 102 and the outlet 104 are configured to comply with International Standard ISO 5356-1 (4th Ed.: 2015). The typical flexible tubing is 22 millimeters (mm) in diameter for use with adult patients. The inside diameter of the inlet 102 is designed to mate with smaller, 15 mm diameter pediatric tubing sets. Suitable size adapters may also be used to accommodate tubing of different diameters.
[0082] The inlet 102 has a receiving portion 126 that may be tapered to have a larger outside diameter 128 abutting the collar 130 to allow the tubing to more easily be affixed to abut the collar 130 and effect a secure air tight connection. The receiving portion 126 also has a length 132 to facilitate the desired secure air tight connection. The inlet 102 is constructed as a conical inlet; and the outlet 104 is constructed to be a socket. Both are constructed in accordance with the ISO standard identified hereinbefore.
[0083] The valve 98 best seen in
[0084] The valve 98 has a slot 146 which is elongated having a length 148 extending along a center line 152 as better seen in
[0085] The channel 110 of the inlet 102 is shown to be circular in cross section having an inside diameter 126 and in turn an area comparable to the cross sectional area of the standard 1 inch supply hose that is the exhaust limb or exhaust circuit from the input and output device 42. The outlet 104 is also circular in cross section having an inside diameter 164 that is here selected to be the same as the inside diameter 126 of the inlet 102. In turn the cross sectional area of the inlet 102 is the same as the cross sectional area of the outlet 104. In some applications, the cross sectional area of the outlet 104 may be larger than the cross sectional area of the inlet 102 to avoid constricting the flow of the exhaust gas and creating a back pressure. The discharge may also have a functional larger cross sectional area so that the discharge does not restrict flow.
[0086] Referring back to
[0087] As seen in
[0088] In operation, it can be seen in
[0089] As stated, to use the filter and water trap 90, the port 100 may be rotated to a first position relative to the valve 98 to form a second path and align the inlet 102 and the outlet 104 to register with or mate with valve aperture 176 at the inlet 102 and valve aperture 178 at the outlet 104 as better seen in
[0090] In other words, the valve 98 can be rotated between a first or filtering position as seen in
[0091] In
[0092] The trunk 190 has a height so that when the filter holder 94 is affixed to the receptacle or cup 92, the trunk extends from the filter holder 94 to the bottom 194 of the receptacle or the cup 92. The filter 184 has a membrane or filter material 206 having a porosity to filter out pathogens. The filter material 206 may also be impregnated with various substances to attack the pathogens. That is, the filter material is impregnated with anti bacterial and anti viral substances to enhance the filtration. The filter material 206 may also be pleated to increase the surface area of the filter to enhance filtration and reduce back pressure.
[0093] As also seen in
[0094] As seen in
[0095] In
[0096] Referring again to
[0097] In
[0098] Turning now to
[0099] The changeable filter 240 of
[0100]
[0101] As seen in
[0102] As seen in
[0103] Referring now to
[0104] The changeable filter 300 as shown to be an alternative type of the changeable inlet filter 450. The changeable filter 300 has a first conduit 302 to receive blended gas 15 from the ventilator output 48. The blended gas 15 is then directed to either a first valve 304 or a second valve 306. As depicted, the first valve 304 is a ball valve shown in cross section with an interior ball 308 having a channel 310 that can be rotated in a housing 312 between open position in which the channel 310 is aligned to pass blended gas therethrough and a second or closed position in which the ball 308 and in turn the channel 310 is rotated by the handle 314 to inhibit movement of blended gas therethrough.
[0105] The second valve 306 is a depiction of valve that has a housing 316 with a disc 318 operable by a handle 320 to move the disc between closed (shown) and open positions as known to those skilled in the art. A gate valve may also be used in lieu of either or both first valve 304 and second valve 306. Any other form of valve may be used that functions to stop and permit flow therethrough.
[0106] The changeable filter 300 has the first valve 304 in a first leg 322 and the second valve 306 in the second leg 324. The first leg 322 has a first filter 326 configured to filter pathogens from the exhaust gas 13 or blended gas 15 to form first filtered gas 329 that is directed to and through third valve 330 to a discharge 334. Similarly, the second leg 324 has a second filter 328 that functions to filter pathogens from the exhaust gas 13 or blended gas 15 and from second filtered gas 331 that is directed to and through a fourth valve 332 to the discharge 334.
[0107] The valves 304, 306, 330 and 332 may be selected to be any one of a ball valve, a gate valve, a disc valve, or other suitable valve as desired by the user. The valves 304, 306, 330 and 332 are operated between open and closed positions for directing exhaust gas 13 or blended gas 15 to and through the first leg 322 and then the second leg 324 in a manner so that no exhaust gas is vented or released to the surrounding area. So for example, valves 304 and 330 are open when valves 306 and 332 are closed. When valves 306 and 332 are closed, the second filter 328 may be removed from the second leg 324 and replaced with a new filter. Upon the connection of a new filter as the second filter 328, valves 306 and 332 may be opened following which valves 304 and 330 are closed. With the valves 304 and 330 closed, the first filter 326 may be removed from the first leg 322 and replaced with a new first filter 326.
[0108] In
[0109] Referring now to
[0110] As better seen in
[0111] In
[0112]
[0113] The kit 400 of
[0114] The conduit or tubing 408, 410, 412, 414, 416, 418 and 420 are each configured with suitable connectors 430 and 432 and a suitable stretch 434 in between. The stretch 434 may vary so the user has different sizes available.
[0115] The kit 400 also contains a suitable water trap 422 and a suitable diversion valve 424 having a handle 426 operable by the user to move it between a first position and a section position to direct exhaust gas into separate legs each with a filter in it like filters 404 and 406. A separate kit comparable to kit 400 (not shown) may have a humidifier in it and no water trap.
[0116] The kit 400 may contain other components including latex or surgical gloves (not shown) for use by operators and sterile wipes (not shown) to maintain suitable cleanliness in the area of operation. Vials or tubes of lubricants for use with the conduit or tubing to effect connections may also be included.
[0117] Turning now to
[0118] The exhaust gas 13 proceeds through the channel 516 into a valve plenum or chamber 518 which is sized to contain the valve 520 that operates between two positions. In the first position 528 shown, it is blocking the first inlet 522 to prevent the flow of the exhaust gas 13 therethrough into a first path plenum 524 and then into the first filter element 502 as shown by dotted arrow 526. The valve 520 is operable from the first position 528 blocking the first inlet 508 as shown to a second position 530 shown in dotted line blocking second inlet 532. When not blocked, the exhaust gas 13 flows as shown by arrow 536 through the second inlet 532 into a second path plenum 534. With the valve 520 in the second position 530 as shown, the exhaust gas 13 proceeds from the valve plenum 518 through the second inlet 532 into the second path plenum 534 and then into the second filter element 504 as discussed more fully hereinafter.
[0119] The valve 520 is shown as a simple face or plate that moves between the two positions 528 and 530 upon operation of a lever not shown in
[0120]
[0121] In
[0122] The first filter element 572 also has a boss 579 which is not shown to engage the locking mechanism. In turn it is not here shown to function to operate the slide 566. It is presently believed, that the boss 579 may be formed with a rim 583 comparable to rim 582 with surface comparable to slanted surface 584 to engage another slanted surface (not shown) formed on the extension 586 of the slide 566. In turn, it is believed that the first filter element 572 can be formed to cause the slide 566 to engage and disengage fingers 562 and 564.
[0123] As further seen in
[0124] Returning to
[0125] As seen in
[0126] As better seen in
[0127] A filter media 680 is shown in
[0128]
[0129] As seen in
[0130] When assembled and connected to operate, the changeable outlet filter 710 receives exhaust gas 13 through the inlet 712. The exhaust gas 13 then passes through one or the other of the inlet openings 744 and 746 which is not blocked by the valve 714 and more particularly by the valve blade 715. After passing through one of the inlet openings 744 and 746, the exhaust gas 13 passes into and through its associated first filter element 726 and second filter element 728. It hen passes through the filter media comparable to that shown in
[0131]
[0132] The half 766 of the housing 762 has a seal material (not shown for clarity) substantially the same as seal material 784 attached or adhered to the wall 786 on the inside 767 of the other half 768 of the assembled housing 762. The seal material 784 is better seen attached to the wall 786 of the other half 768 and is seen separately in
[0133] The seal material 784 in this embodiment is EPDM foam tape but may be other suitable material to form an effective seal between the walls 782 and 786 and the cartridge 764 as more fully discussed hereinafter. Openings 797 are formed in the seal material 785 when installed to register with the channel 782 and a similar channel formed in outlet structure 773.
[0134] The changeable cartridge 764 also seen in
[0135] When the first half 800 and second half 802 are joined to form the cartridge 764, they form a void space or an interior 803 that is filled with suitable filter material 812. That is, filter material may be layered or sandwiched filter material of the type to filter pathogens and known to those of skill in the art and as discussed hereinafter. The filter material may be flat sheets cut to fit and layered. The filter material may also be pleated to increase the surface area; and the filter material may be formed to function as HME filter material to absorb moisture from exhaust gas leaving the patient and humidify breathable air being inspirated by the patient.
[0136] The cartridge 764 has a length 814 that is less than the length 816 of the housing 762 so that when the cartridge 764 is inserted into the interior or inside 767 of the housing 762 with the back wall 822 of the cartridge 764 is not flush with the edge 790. A ledge or lip not shown is then formed to allow another cartridge to be lined up ready to push the first cartridge from its operational location installed in the housing 782. Thus the front wall 824 when installed is set back from the edge 791 of the housing 762 from about to of an inch.
[0137] When installed in the housing 782, the aperture 818 of the first cartridge formed in the main wall 820 of the first half 800 of the cartridge 764 registers with the channel 782 of the inlet structure 772. At the same time, a second aperture 826 shown in phantom in the other main wall 828 of the second half 802 of the cartridge 764 registers with the second wall aperture formed in the second wall 786 in communication with a channel (not shown) in the outlet 773 comparable to channel 782 in the inlet structure 772. It may be noted that when the cartridge 764 is inserted into the interior or volume 767 of the housing 762, it is secured in place by a ball and detent arrangement such as balls or bumps 830 and 832 and comparable balls or bumps (not shown) on the side opposite to the top 834 which are positioned to register with corresponding four detents like detent 836 formed in the housing 762.
[0138] The changeable outlet filter 760 of
[0139] A second cartridge 850 is then provided comparable or identical in structure and function to cartridge 764. Thus the number 850 is assigned to the same illustration for cartridge 764 to show they are identical. The second cartridge 850 is then pushed or urged toward the interior or volume 767 of the housing 762 in alignment with or to register with the cartridge 764 in place in the housing 762 and to in turn contact rear wall 802 of cartridge 764. By advancing cartridge 850 into the housing 762, one is at the same time advancing the cartridge 764 through and outwardly of the housing 762 with the walls 820 and 828 of the exiting cartridge 764 and then the walls 820 and 828 of the entering cartridge 850 functioning as valve 66 first closing or blocking flow of exhaust gas 13 into the exiting cartridge 764 and then opening as the apertures 818 and 826 come into alignment with the inlet channel 782 in the housing 762 as well as the outlet channel (not shown) in the outlet 783. The cartridge 850 thus functions as filter 70 supplying filtered exhaust gas 75 though the outlet aperture 826 to the outlet channel in the outlet structure 773 and then to atmosphere or to the exhaust valve 28 in the ventilator 10 (
[0140] Turning to
[0141] As shown in
[0142] The outlet 914 is a socket similar to the inlet 912 both having an inner wall (not shown) and an outer wall 930 The inlet 912 and outlet 914 are both formed in accordance with international standards as stated herein to fit with standard 22 mm and 15 mm medical tubing. In addition to the inlet wall 922 and outlet wall 924, the housing 902 has a plurality of sides at its top 932 and its bottom 934 to form the volume or inside 928. As shown, the top 932 has a top slot 936 and the bottom 934 has the bottom slot 938. The bottom slot 938 has a depth 940 and a width 942 and extends the length 944 of the housing 902. The top slot 936 is identical except that it has an opening 946 positioned centrally along the length 944 having a width 948 and a length 950 sized to register with raised portions 952 on the ridge 954 of the cartridge 904 as hereinafter discussed.
[0143] The second cartridge 904 seen in
[0144] As illustrated in a simplified exploded view of a cartridge 964 in
[0145] Returning to
[0146] Similar to the filter arrangement of
[0147] It should be noted that in some configurations, the first cartridge 903 and the second cartridge 904 of the filter 900 may also have connectors to attach one to the other so that the first cartridge cannot be removed before the second cartridge is properly in place. A train coupling arrangement as hereinbefore discussed is a suitable connector. Other connectors may be used that inhibit detachment of the first cartridge 903 from the second cartridge 904 until the second cartridge 904 is positioned and formed the second path.
[0148] In another configuration seen in
[0149] It may be noted that filters herein disclosed may be used as the inlet filter 12 as well as the changeable outlet filter 46. The filter structures particularly illustrated in
[0150] Those skilled in the art will recognize disclosed structures and methods may be practiced using materials that may be different from those identified hereinabove without departing from the principles as disclosed. Only specific embodiments have been disclosed to illustrate the structures and methods as defined by the appended claims.