US20070107737A1 - Nasal cannula - Google Patents

Abstract

A nasal cannula comprising: a base portion defining a gas passageway and one or more nozzles defining a second gas passageway in gaseous communication with the first gas passageway for directing a therapeutic flow of gas to a user's nares. The nasal cannula may include one or more sensors for measuring the properties of gas within a user's nares. The nozzle may be a nasal insert that is inserted into the user's nares; recesses or grooves are provided for preventing sealing of the nasal insert with the nare. The nozzle may be shaped to avoid insertion into the user's nares, thus preventing sealing with the nares. A stop may be positioned between two nozzles to engage a user's columella and prevent the nozzles from inserting into the user's nares. Elongate extensions are provided for inserting into the user's nares and supporting sensors for measuring gas properties therein.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS
• This application claims the benefit of U.S. Provisional Patent Application Ser. No. 60/716,776, filed Sep. 12, 2005, of which the contents are incorporated herein by reference in their entirety.
BACKGROUND OF THE INVENTION
• Nasal cannulas are used to deliver respiratory gases for therapeutic effect, including O₂therapy, treatment for sleep apnea, and respiratory support. However, treatment with certain types of nasal cannulas may be limited by the lack of information available on important treatment parameters. These parameters include information regarding the gases within the user's upper airway, such as pressure, flow rate, and carbon dioxide build up. These and other data may be useful in judging the efficacy of treatment as well as for controlling and monitoring treatment.
• In addition, prior art nasal cannula designs (especially those designed for neonatal oxygen therapy) may undesirably create a seal with the user's nares, which may have detrimental effects on the user's health.
BRIEF DESCRIPTION OF THE DRAWINGS
• Reference will now be made to the accompanying drawing figures, which are not necessarily drawn to scale.
• FIG. 1 is a perspective view of a nasal cannula according to a particular embodiment of the invention.
• FIG. 2 is a perspective view of a nasal cannula according to a further embodiment of the invention.
• FIG. 3 is a perspective view of a nasal cannula according to another embodiment of the invention.
• FIG. 4 is a perspective view of a nasal cannula according to yet another embodiment of the invention.
• FIG. 5 is a front perspective view of a nasal cannula according to a further embodiment of the invention.
• FIG. 6 depicts a cross section of a nasal insert of a nasal cannula according to a particular embodiment of the invention.
• FIG. 7 depicts a cross section of a nasal insert of a nasal cannula according to a further embodiment of the invention.
• FIG. 8A is a front perspective view of a nasal cannula according to another embodiment of the invention.
• FIG. 8B is a rear perspective view of the nasal cannula shown inFIG. 8A.
• FIG. 8C is a perspective cross-sectional view of the nasal cannula shown inFIG. 8A.
• FIG. 9 is a perspective view of a nasal cannula according to a further embodiment of the invention.
• FIG. 10 is a perspective view of a nasal cannula according to another embodiment of the invention.
• FIG. 11 is a perspective view of a nasal cannula according to a further embodiment of the invention.
• FIG. 12 is a perspective view of a nasal cannula according to yet another embodiment of the invention.
• FIG. 13 illustrates an embodiment of a nasal cannula in use on a patient, according to one embodiment of the invention.
• FIG. 14 illustrates another embodiment of a nasal cannula in use on a patient, according to a further embodiment of the invention.
DESCRIPTION OF VARIOUS EMBODIMENTS OF THE INVENTION
• The present inventions now will be described with reference to the accompanying drawings, in which some, but not all embodiments of the inventions are shown. Indeed, these inventions may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Like numbers refer to like elements throughout. For example,elements130,230,330,430,530,830, and930 are all nasal inserts according to various embodiments of the invention.
• Overview of Functionality
• Nasal cannula according to various embodiments of the invention may be configured to deliver high-flow therapeutic gases to a patient's upper airway through the patient's nose. Such gases may include, for example, air, humidity, oxygen, therapeutic gases or a mixture of these, and may be heated or unheated. In particular embodiments of the invention, the cannula may be useful for CPAP (continuous positive airway pressure) applications, which may be useful in the treatment of sleep apnea and in providing respiratory support to patients (e.g., after abdominal surgery), to alleviate snoring, or for other therapeutic uses.
• Nasal cannula according to particular embodiments of the invention include (or are adapted to facilitate the positioning of) one or more sensors adjacent or within one or more of the cannula's nasal inserts. Accordingly, the nasal cannula may be configured so that at least a portion of one or more sensors is in place in one or both of a user's nares when the nasal cannula is operably worn by the user. This may be particularly helpful in evaluating the environment of the internal portion of the user's nose and/or the user's upper airway. As described in greater detail below, in various embodiments of the invention, the cannula is adapted so that it will not create a seal with the patient's nares when the cannula is in use.
• Nasal cannula according to other embodiments of the invention include nozzles that are adapted to remain outside of a user's nares while the cannula is in use. Accordingly, the nozzles avoid sealing with the patient's nares while the cannula is in use. In some embodiments, the nasal cannula include elongate extensions that are inserted into the user's nares to detect pressure in one or both nares.
• In certain embodiments of the invention, sensors are provided adjacent or within both of the nasal cannula's nasal inserts. In various other embodiments, sensors are provided adjacent or within one or more elongate extensions that extend into the user's nares. In various embodiments, elongate extensions may be used in conjunction with nasal inserts or with nozzles. The use of sensors may be useful, for example, in monitoring environmental changes from one of the user's nares to the other. This information may be helpful, for example, in determining when the dominant flow of air changes from one of the user's nares to the other, which may affect the desired flow characteristics of therapy. Accordingly, data from each nare may provide information which may be useful in establishing or modifying the user's treatment regimen.
• Overview of Exemplary Cannula Structures
• Acannula100 according to one embodiment of the invention is shown inFIG. 1. As may be understood from this figure, in this embodiment, thecannula100 includes a hollow, elongatedtubular base portion105 that includes acentral portion110, afirst end portion115, and asecond end portion120. The first andsecond end portions115,120 may be angled relative to thecentral portion110 as shown inFIG. 1.
• In various embodiments of the invention, thecannula100 includes afirst inlet117 adjacent the outer end of thefirst end portion115, and asecond inlet122 adjacent the second end portion120 (in other embodiments, the cannula may include only one such inlet). Thecannula100 further comprises a pair of hollow, elongated, tubular nasal inserts (e.g., nasal catheters)125,130 that extend outwardly from the nasal cannula'sbase portion105 and that are in gaseous communication with the base portion's interior. In various embodiments, the respective central axes of thenasal inserts125,130 are substantially parallel to each other, and are substantially perpendicular to the central axis of thecentral portion110 of the nasal cannula'sbase portion105.
• In particular embodiments of the invention, the cannula defines at least one conduit that is adapted to guide a sensor so that the sensor is introduced adjacent or into the interior of the cannula so that, when the cannula is being operably worn by a user, the environment being monitored by the sensor reflects that of the internal portion of the user's nose and/or the user's upper airway. In various embodiments of the invention, a user may temporarily insert the sensor into or through the conduit to determine correct settings for the cannula system, and then may remove the sensor after the correct settings have been achieved. In other embodiments, the sensor may be left in place within the conduit for the purpose of monitoring gas data within (or adjacent) the cannula over time (e.g., for purposes of controlling the user's therapy regimen). In a further embodiment, the sensor may be positioned adjacent an outlet of the conduit.
• The sensor may be connected (e.g., via electrical wires) to a computer that is controlling the flow of respiratory gases into the cannula. The computer may use information received from the sensor to control this flow of gas and/or other properties of the system, or may issue an alarm if the information satisfies pre-determined criteria (e.g., if the information indicates potentially dangerous conditions within the patient's airway).
• As may be understood fromFIGS. 8A-8C, in a particular embodiment of the invention, at least one of the cannula'sconduits850 is defined by, and extends within, a side wall of thecannula800. Alternatively, the conduit may be disposed within an interior passage defined by the cannula. For example, one or more of the conduits may be defined by a tube that is attached immediately adjacent an interior surface of the cannula (e.g., adjacent an interior surface of the cannula's base portion, or an interior surface of one of the cannula's nasal inserts). The cannula's conduits are preferably adapted for: (1) receiving a flow of gas at one or more inlets that are in communication with the conduit, and (2) guiding this flow of gas to an outlet in the cannula. In various embodiments, one or more of the inlets is defined within an exterior portion of one of the cannula's nasal inserts.
• As may be understood fromFIG. 1, in various embodiments of the invention, each of the cannula'sconduit outlets136,141 is located at the end of a respective elongate, substantially tubular,outlet member135,140. For example, in the embodiment shown inFIG. 1, thecannula100 includes afirst outlet member135 that is substantially parallel to the cannula's firstnasal insert125. In this embodiment, thefirst outlet member135 and the firstnasal insert125 may be positioned on opposite sides of the nasal cannula'sbase portion105 as shown inFIG. 1. Similarly, in a particular embodiment of the invention, thecannula100 includes asecond outlet member140 that is substantially parallel to the cannula's secondnasal insert130. Thesecond outlet member140 and secondnasal insert130 are also preferably positioned on opposite sides of the nasal cannula'sbase portion105.
• In various embodiments of the invention, a sensor (e.g., a pressure, temperature, or O₂sensor) is provided adjacent at least one of (and preferably each of) the cannula'soutlets136,141 and is used to measure the properties of gas from thatoutlet136,141. In a further embodiment of the invention, accessory tubing is used to connect eachoutlet135,140 with at least one corresponding sensor (and/or at least one external monitoring device) that may, for example, be spaced apart from thecannula100.
• In yet another embodiment of the invention, one or more sensors are provided within the conduit, and used to measure the properties of gas accessed through the conduit. In this embodiment, information from each sensor may be relayed to a control system outside the cannula via, for example, an electrical wire that extends from the sensor and through theoutlet135,140 of the conduit in which the sensor is disposed.
• In alternative embodiments of the invention, each of the cannula's conduits may extend: (1) from theinlets152,154; (2) through, or adjacent, a side wall of one of the cannula's nasal inserts125,130; (3) through, or adjacent, a side wall of the cannula'sbody portion105; and (4) to anoutlet135,140 that is defined within, or disposed adjacent, the cannula'sbody portion105. In one such embodiment, the conduit comprises a substantially tubular portion that is disposed adjacent an interior surface of the cannula's body portion.
• As may be understood fromFIG. 2, in certain embodiments of the invention, thecannula200 includes at least onesensor245 that is integrated into an exterior portion of the cannula200 (e.g., within arecess223 formed within an exterior surface of one of the cannula's nasal inserts225,230). In this embodiment, information from thesensor245 may be relayed to a control system outside thecannula200 via anelectrical wire246 that extends from thesensor245, through a conduit, and out anoutlet235,240 in the conduit. In various embodiments of the invention, the conduit extends through or adjacent an interior portion of a side wall of one of the cannula's nasal inserts225,230 and/or through or adjacent an interior portion of a side wall of the cannula's body portion205.
• In particular embodiments of the invention, at least onesensor245 is fixedly attached to thecannula100 so that it may not be easily removed by a user. Also, in particular embodiments, at least onesensor245 is detachably connected adjacent thecannula100 so that thesensor245 may be easily detached from (and, in certain embodiments, reattached to) thecannula100.
• Thecannula1000 includes a hollow, elongatedtubular base portion1005 that includes acentral portion1010, afirst end portion1015, and asecond end portion1020. The first andsecond end portions1010,1015 may be angled relative to thecentral portion1010, as shown inFIG. 10. In various embodiments of the invention, thecannula1000 includes afirst inlet1017 adjacent the outer end of thefirst end portion1015, and asecond inlet1022 adjacent the outer end of thesecond end portion1020.
• Thecannula1000 further comprises a pair of hollow, elongated, tubular nozzles (afirst nozzle1026 and a second nozzle1031) that extend outwardly from the nasal cannula'sbase portion1005. In various embodiments, the respective central axes of thenozzles1026,1031 are substantially parallel to each other and are substantially perpendicular to the central axis of thecentral portion1010 of the nasal cannula'sbase portion1005. In various embodiments, thenozzles1026,1031 define conduits that are in gaseous communication with the interior of the cannula'sbase portion1005. In particular embodiments of the invention, the first andsecond nozzles1026,1031 are adapted to be positioned outside of a user's nares while the cannula is in use. In particular embodiments, thenozzles1026,1031 each define a respective nozzle outlet. For example, thefirst nozzle1026 defines afirst nozzle outlet1083, and thesecond nozzle1031 defines asecond nozzle outlet1084. In various embodiments, when thenasal cannula1000 is operatively positioned adjacent a user's nares, each of the nozzle'soutlets1083,1084 is positioned to direct a focused flow of gas into a corresponding one of the user's nares.
• In alternative embodiments, such as the embodiment shown inFIG. 12, thenasal cannula1200 may include asingle nozzle1227 that defines a conduit or air passageway that is in gaseous communication with an interior portion of the cannula'sbase portion1205. As described in greater detail below, in various embodiments, thenozzle1227 extends outwardly from the cannula'sbase portion1205 and has an oblong, or elliptical, cross-section. In this and other embodiments, thenozzle1227 is shaped to deliver a focused flow of gas simultaneously into both of a user's nares when thecannula1200 is in use.
• In various embodiments, the nasal cannula includes one or more elongate extensions that are adapted for insertion into one or more of the user's nares. For example, returning to the embodiment shown inFIG. 10, thenasal cannula1000 may include multiple elongate extensions (for example a firstelongate extension1070 and a second elongate extension1072) that are long enough to allow each of theelongate extensions1070,1702 to be inserted into a respective one of the user's nares while thenasal cannula1000 is in use. In various embodiments, each of theelongate extensions1070,1072 may have a central axis that runs substantially parallel to the central axis of acorresponding nozzle1026,1031. For example, as can be understood fromFIG. 10, in certain embodiments, a firstelongate extension1070 has a central axis that lies substantially parallel to and below the central axis of a correspondingfirst nozzle1026, when the nasal cannula is operatively positioned adjacent a user's nares. Similarly, in various embodiments, a secondelongate extension1072 has a central axis that lies substantially parallel to and below the central axis of a correspondingsecond nozzle1031, when thenasal cannula1000 is operatively positioned adjacent a user's nares. In various other embodiments, the elongate extensions may lie within, and extend outwardly from, their correspondingnozzles1070,1072.
• As a further example,FIG. 12 illustrates an exemplarynasal cannula1200 having multiple elongate extensions (a firstelongate extension1270 and a second elongate extension1272), which both lie substantially below asingle nozzle1227 when thenasal cannula1200 is in an operative position adjacent the user's nose. In some embodiments, the central axes of the first and secondelongate extensions1270,1272, may be substantially parallel to the central axis of thenozzle1227. Also, in various embodiments, one or both of theelongate extensions1270,1272 may lie within thenozzle1227. In this and other embodiments, a distal end of each of theelongate extensions1270,1272 may extend beyond a distal end of thenozzle1227.
• As described above, in certain embodiments of the invention, the nasal cannula includes one or more sensors that are adapted to measure gas data (e.g., gas pressure) within the user's nares while the nasal cannula is in use. For example, thenasal cannula1000 shown inFIG. 10 may include a sensor positioned adjacent the distal end of one or both of the first and secondelongate extensions1070,1072. In various embodiments, each elongate extension may be adapted to: (1) support a sensor adjacent (e.g., at) the distal end of the elongate extension; and (2) support a wire that is simultaneously connected to the sensor and a control mechanism that is adapted to adjust the properties of gas flowing through thecannula1000.
• In other embodiments, the elongate extensions define conduits. For example, the sensor(s) may be positioned within the interior or exterior of the elongate extensions and information from the sensor(s) may be relayed to a control system via a wire extending through a conduit (for example,conduit1023 ofFIG. 10) or passageway defined by each of the elongate extensions. In one embodiment, as shown, for example, inFIG. 10, theconduit1023 is shaped similarly to the nasal cannula'sbase portion1005, and lies substantially below thebase portion1005 when thenasal cannula1000 is operatively in use. In various embodiments, theconduit1023 is positioned within thebase portion1005 such that the first and secondelongate extensions1070,1072 lie within, and extend outwardly from, the respective first andsecond nozzles1026,1031.
• In various embodiments, each elongate extension defines a respective conduit that can serve as an air passageway. For example, in certain embodiments, each conduit is adapted to provide a passage that permits gaseous communication between a user's nares and a control system or other device for measuring and adjusting the properties of the air. In this and other embodiments, a sensor may be positioned at the control box to measure the properties (e.g., pressure) of air in the user's nares. In some embodiments, the elongate extensions define a conduit that serves both as an air passageway as well as a conduit for allowing a wire to pass from a sensor positioned adjacent the tip of the elongate extension to the control system or other device.
• Data Monitored by Sensors
• In various embodiments of the invention, such as those described above, one or more sensors may be positioned to measure gas data within an interior portion of one of the nasal cannula's conduits, or to measure gas data adjacent an exterior portion of the cannula. In such embodiments, one or more sensors may be, for example, positioned adjacent an interior or exterior surface of the cannula. In certain embodiments of the invention, one or more of the cannula's sensors is adapted to monitor one or more of the following types of data within the cannula's conduits, or adjacent the cannula's exterior surface (e.g., adjacent a side portion, or distal end of, one of the cannula's nasal inserts): (1) gas pressure; (2) gas flow rate; (3) carbon dioxide content; (4) temperature; (5) moisture level; and/or (6) oxygen content.
• Absolute vs. Relative Pressure Measurements
• In various embodiments of the invention, the cannula may be configured for sensing absolute pressure within, or adjacent, a particular portion of the cannula. Similarly, in particular embodiments, the cannula may be configured to measure the difference between the pressure at two different locations within the cannula. This may be done, for example, by providing two separate sensors (e.g., that are positioned in different locations within one of the cannula's conduits), or by providing two physically distinct gas intake conduits, each of which is adapted for routing gas from a different location within the cannula. For example, in various embodiments of the invention shown inFIG. 1, thefirst inlet152 may be connected to a first intake conduit that is adapted for routing gas to a first sensor, and thesecond inlet154 may be connected to a physically separate second intake conduit that is adapted for routing gas to a second pressure sensor. Information from the first and second sensors may then be used to calculate the difference in pressure between the first andsecond inlets152,154. Alternatively, a differential pressure sensor may be used.
• Suitable Sensors
• Suitable sensors for use with various embodiments of the invention include electronic and optical sensors. For example, suitable sensors may include: (1) Disposable MEM Piezoelectric sensors (e.g., from Silex Microsensors); (2) light-based sensors such as a McCaul O₂sensor—see U.S. Pat. No. 6,150,661 to McCaul; and (3) Micro-pressure sensors, such as those currently available from Honeywell.
• Non-Sealing Feature
• As shown inFIG. 4, in various embodiments of the invention, one or more of the nasal cannula's nasal inserts425,430 defines one or more recesses423 (e.g., grooves, semicircular recesses, or other indentations or conduits) that extend along a length of the nasal insert's exterior surface. As may be understood from this figure, in various embodiments of the invention, at least one of theserecesses423 is an elongate groove that extends from adjacent a distal surface of thenasal insert325,330,425,430 and past the midpoint between: (1) the nasal insert's distal surface and (2) the portion of thenasal insert425,430 that is immediately adjacent the nasal cannula'sbase portion305,405. As may also be understood from this figure, in various embodiments of the invention, eachgroove423 extends substantially parallel to the central axis of its respectivenasal insert425,430.
• In particular embodiments of the invention, such as the embodiment shown inFIG. 4, at least one of the nasal cannula's nasal inserts425,430 is configured so that when the nasal inserts425,430 are operatively positioned within a user's nares, the nasal inserts do not form an airtight seal with the user's nares. This may be due, for example, to the ability of air to flow adjacent the user's nare throughrecesses423 in the nasal inserts425,430 when the user is wearing the nasal cannula.
• FIGS. 5-8 depict additional embodiments of the invention that are configured so that when the cannula's nasal inserts are operatively positioned adjacent (e.g., partially within) the user's nares, the nasal inserts do not form a seal with the user's nares. For example, in the embodiment shown inFIG. 5, at least one (and preferably both) of the cannula's nasal inserts525,530 comprise an inlet555 (which may, for example, be substantially tubular), and one ormore flange portions560,561 that are adapted to maintain a physical separation between an exterior side surface of theinlet555 and a user's nare when thenasal insert525,530 is inserted into the user's nare.
• For example, in the embodiment of the invention shown inFIG. 5, each of the cannula's nasal inserts525,530 includes a substantiallytubular inlet555 and a pair of co-facing,elongated flanges560,561 that each have a substantially C-shaped cross section. In this embodiment, these C-shapedflanges560,561 cooperate with a portion of the exterior of theinlet555 to form a substantially U-shaped channel (which is one example of a “nasal lumen”) through which ambient air may flow to and/or from a user's nasal passages when thecannula500 is operatively in place within the user's nares. In this embodiment, when the nasal inserts525,530 are properly in place within the user's nares, respiratory gas is free to flow into the -user's nose through theinlet555, and ambient air is free to flow into and out of the user's nose through a passage defined by: (1) theflanges560,561; (2) the exterior side surface of theinlet555 that extends between theflanges560,561; and (3) an interior portion of the user's nose. In various embodiments, air may flow to and/or from a user's nose through this passage when thecannula500 is operatively in place within the user's nares. A pathway (e.g., a semicircular pathway) may be provided adjacent the interior end of this U-shaped channel, which may act as a passageway for gas exhaled and inhaled through the U-shaped channel.
• The general embodiment shown inFIG. 5 may have many different structural configurations. For example, as shown inFIG. 6, which depicts a cross section of a nasal insert according to a particular embodiment of the invention, the respiratory gas inlets of the cannula's nasal inserts655 may be in the form of a tube having an irregular cross section (e.g., a substantially pie-piece-shaped cross section) rather than a circular cross section. Alternatively, as may be understood fromFIG. 7, the respiratory gas inlets of the cannula's nasal inserts755 may be in the form of a tube having a substantially half-circular cross section rather than a circular cross section.
• Similarly, as may be understood fromFIGS. 6 and 7, the shape and size of the cannula's flanges may vary from embodiment to embodiment. For example, in the embodiment shown inFIG. 6, each of theflanges660,661 has a relatively short, substantially C-shaped cross section and the distal ends offlanges660,661 are spaced apart from each other to form a gap. As shown inFIG. 7, in other embodiments, each of theflanges760,761 may have a relatively long, substantially C-shaped cross section and the distal ends of theflanges760,761 may be positioned immediately adjacent each other.
• As may be understood fromFIG. 7, in various embodiments of the invention, a separation763 (e.g., a slit, such as an angular slit) is provided between theflanges760,761. This may allow theflanges760,761 to move relative to each other and to thereby conform to the nare in which the nasal insert is inserted. In other embodiments, the cross section of the nasal inserts is substantially as that shown inFIG. 7, except that noseparation763 is provided within the semi-circular flange portion. Accordingly, in this embodiment of the invention, a substantially semi-circular portion of the exterior of the air inlet cooperates with a substantially semi-circular portion of the flange portion to form an exterior having a contiguous, substantially circular cross section. One such embodiment is shown inFIGS. 8A-8C.
• As may be understood fromFIGS. 8A-8C, in this embodiment, when thecannula800 is in use, respiratory gas may flow into the user's nose through passageways881 (e.g., a portion of which may be defined by a corresponding respiratory gas inlet855) that extend through each of the cannula's nasal inserts825,830. Apathway885 of substantially semi-circular cross section extends between the distal end of eachnasal insert825,830 to a substantiallysemicircular outlet865 defined within the cannula'sbase805. In various embodiments, when thecannula800 is in use, the user may inhale and exhale gas through thispathway885.
• In certain embodiments, as discussed above, aconduit850 is provided in each of the cannula's nasal inserts825,830 (seeFIG. 8C). Each of theseconduits850 may be adapted to: (1) receive gas from the interior of acorresponding pathway885 and/or from adjacent the exterior of one of the cannula's nasal inserts825,830, and (2) guide the gas out of acorresponding outlet835,840 in thecannula800. As discussed above, one or more sensors may be disposed within, or adjacent, theconduit850 and used to assess one or more attributes of gas flowing through or adjacent theconduit850.
• It should be understood that the embodiments of the invention shown inFIGS. 4-8 and related embodiments may have utility with or without the use of sensors or sensor conduits. It should also be understood that the various nasal inserts may be configured to be disposed in any appropriate orientation within the user's nares when the cannula is operably positioned within the user's nares. For example, in one embodiment of the invention, the cannula may be positioned so that the cannula's nasal lumen is immediately adjacent, or so that it faces anterior-laterally away from, the user's nasal spine.
• Turning to yet another embodiment of the invention, as shown inFIG. 9, thecannula900 and corresponding sensor may be adapted so that atube inlet970,972 for at least one sensor (or the sensor itself) is maintained adjacent, and spaced a pre-determined distance apart from, the distal end of a respectivenasal insert925,930. In this embodiment, the sensor (or sensor intake inlet) may be spaced apart from the rest of thenasal cannula900 adjacent one of the nasal cannula's outlet openings.
• As may be understood fromFIG. 10, in various embodiments, the first andsecond nozzles1026,1031 of the nasal cannula are configured to remain outside of the user's nares while the cannula is in use. For example, the nozzles may be of a length such that, when the cannula is in use, the distal ends of thenozzles1026,1031 lie adjacent, but outside, the user's nares. By preventing insertion of thenozzles1026,1031 into the nares, sealing of the nares can be avoided. As may be understood fromFIG. 13, in various embodiments, when the nasal cannula is in an operative position adjacent the user's nares, an outlet portion (and distal end) of eachnozzle1326,1331 is spaced apart from, and substantially in-line (e.g., substantially co-axial) with, a corresponding one of the patient's nares. In various embodiments, when the nasal cannula is operatively in use, the outlet of each nozzle is spaced apart from the patient's nares and each nozzle is positioned to direct a focused flow of gas into a particular respective one of the user's nares.
• As may be understood fromFIG. 11, in particular embodiments, astop1190 may extend outwardly from thebase portion1105 of the nasal cannula. In some embodiments, thestop1190 lies in between the first andsecond nozzles1126,1131 and defines a central axis that runs substantially parallel to the respective central axes of thenozzles1126,1131. Thestop1190, in some embodiments, may extend outwardly from the nasal cannula's base portion1105 a length greater than that of thenozzles1126,1131. In this manner, thestop1190 prevents thenozzles1126,1131 from being inserted into the user's nares when thenasal cannula1100 is in use.
• For example, thestop1190 may be positioned so that when thenasal cannula1100 is in use, the stop is designed to engage the columella of the user's nose and thereby prevent thenozzles1126,1131 from being inserted into the user's nares. In various embodiments, the first andsecond nozzles1126,1131 are positioned on either side of thestop1190 so that when thenasal cannula1100 is operatively in use, the eachnozzle1126,1131 will be spaced apart from a respective particular one of the patient's nares and will be positioned to direct a focused flow of gas into that particular nare by, for example, being positioned so that the outlet (and distal end) of each nozzle (first outlet1183 and second outlet1184) is substantially in-line (e.g., substantially co-axial) with, a corresponding one of the patient's nares.
• As may be understood fromFIG. 12, in various embodiments, thenasal cannula1200 may include only asingle nozzle1227. Thenozzle1227, in various embodiments, has an oblong or substantially elliptical cross-section. In these embodiments, the major axis of the ellipse runs substantially parallel to the central axis of thebase portion1205 of the nasal cannula. In one embodiment, thenozzle1227 is wide enough to allow air to flow into both of a user's nares when the nasal cannula is in use. For example, in various embodiments, the width of the nozzle1227 (e.g., a length defined by the major axis of the nozzle's elliptical cross section) may be approximately equal to (or greater than) the total width of the user's nares.
• As may be understood fromFIG. 14, when the nasal cannula1400 is operatively in use, a firstlateral side1430 of thenozzle outlet1429 is spaced apart from, and adjacent, a user's first nare, and a secondlateral side1430 of thenozzle1429 is spaced apart from, and adjacent, the user's second nare. In this and other configurations, the nozzle1422 is configured to direct a focused flow of gas simultaneously into each of the user's nares. In various embodiments, when the nozzle is of a width approximately equal to (or greater than) the total width of the user's nares, and other widths, thenozzle1227 is sufficiently wide to prevent thenozzle1227 from being inserted into a user's nare, thus preventing sealing of the nasal cannula with the nare.
• In various other embodiments, the cannula's single nozzle may have a different cross-section that is not oblong or elliptical. For example, the nozzle may have a substantially circular cross-section, with a diameter that is wide enough to allow air to flow into both of a user's nares when the cannula is in use, while simultaneously being wide enough to prevent insertion into a single nare. In various other embodiments, the nasal cannula may have more than one nozzle, each having a substantially oblong cross section and a width that prevents insertion into each of a user's nares.
• In various embodiments, one or more of the cannula's elongate extensions has a diameter that is adapted to prevent sealing with the user's nares. For example, the elongate extension(s) may have a diameter that is substantially narrower than a user's nares, so that sealing is avoided. In other embodiments, the elongate extension(s) may include features such as grooves or recesses, as described above, to prevent sealing when inserted into a user's nare(s).
• Exemplary Use of the Cannula
• To use a cannula according to a particular embodiment of the invention, a physician or technician may have a patient use the cannula for a brief period of time, while the physician or technician monitors information received from the cannula's various sensors, or the information may be recorded for later analysis. The physician or technician may then use this information to adjust the structure or operation of the cannula until the cannula's sensors indicate that the patient's upper airway environment satisfies certain conditions.
• Similarly, in various embodiments, the cannula's sensors may be used to monitor conditions within the patient's upper airway over time. In a particular embodiment, the cannula's sensors may be connected to a control system that will automatically alter or modify the flow of therapeutic gas into the cannula if information from the sensor indicates undesirable conditions within the patient's upper airway. In further embodiments of the invention, the sensor is connected to a control system that issues an alarm if information from the cannula's sensors indicate undesirable conditions within the patient's airway.
• FIGS. 13 and 14 depict various embodiments of nasal cannulas being used on a patient. As may be understood fromFIG. 13, for example, a nasal cannula is used on a young or small infant for high flow therapy. For example, a nasal cannula similar to that shown inFIG. 10 can be used. In various embodiments, first and secondelongate extensions1370,1372 are inserted into the patient's nares, while corresponding first andsecond nozzles1326,1331 remain adjacent and external to the patient's nares. As may be appreciated, when the nasal cannula is in use, air flows into the patient's nares via the nozzles.FIG. 14 depicts one embodiment of a nasal cannula in use on a patient. In one embodiment, a nasal cannula such as that shown inFIG. 12 can be used. As may be understood fromFIG. 14, a nasal cannula having asingle nozzle1427 can be used, in which the nozzle is sized and shaped (e.g., is elliptical and/or wider than a patient's nare) to prevent insertion into the patient's nares. In various other embodiments, nasal cannula having nasal inserts, as described throughout, can be used. In these embodiments, the nasal inserts are inserted into the user's nares while the cannula is in use. Nasal cannula according to embodiments of the invention can be used on a variety of patients.
CONCLUSION
• Many modifications and other embodiments of the inventions set forth herein will come to mind to one skilled in the art to which these inventions pertain having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is to be understood that the inventions are not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. For example, although the embodiment shown inFIG. 1 shows eachnasal insert125,130 having a twoinlets152,154, in alternative embodiments of the invention, one or more of the nasal inserts125,130 may have more or less than two inlets (and/or more or less than two sensors). Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.

Claims (38)

1. A nasal cannula comprising:

a base portion defining a first therapeutic gas passageway;

a nasal insert disposed adjacent said base portion and defining a second therapeutic gas passageway, said first therapeutic gas passageway being in gaseous communication with said second therapeutic gas passageway; and

at least one sensor for measuring the properties of gas adjacent said nasal insert.

2. The nasal cannula ofclaim 1, wherein said nasal insert further defines an elongated conduit that is adapted to route gas from adjacent an exterior portion of said nasal insert and through said conduit and to said sensor.

3. The nasal cannula ofclaim 2, wherein said at least one sensor is disposed within said conduit.

4. The nasal cannula ofclaim 2, wherein:

said nasal cannula defines an outlet for said conduit; and

said sensor is disposed adjacent said outlet.

5. The nasal cannula ofclaim 1, wherein:

said nasal insert is a first nasal insert;

said at least one sensor comprises a first sensor;

said data is a first set of data; and

said nasal cannula comprises:

a second nasal insert disposed adjacent said base portion and defining a third therapeutic gas passageway, said third therapeutic gas passageway being in gaseous communication with said first therapeutic gas passageway, and

a second sensor for measuring the properties of gas adjacent said second nasal insert.

6. A nasal cannula comprising:

a base portion defining a first interior portion;

a nasal insert disposed adjacent said base portion and defining a second interior portion, said first interior portion being in gaseous communication with said second interior portion; wherein:

said nasal insert defines a passage that is adapted to guide a sensor between:

(a) a first position in which the sensor is outside said cannula, and

(b) a second position in which the sensor is positioned to monitor gas data adjacent an exterior portion of said cannula.

7. A nasal cannula comprising:

a base portion defining a first interior portion;

a nasal insert disposed adjacent said base portion and defining a second interior portion, said first interior portion being in gaseous communication with said second interior portion, wherein:

said nasal insert defines a recess that is adapted to prevent said nasal insert from creating a seal with a user's nare when the nasal insert is operatively positioned within said nare.

8. The nasal cannula ofclaim 7, wherein said recess comprises an elongate groove.

9. The nasal cannula ofclaim 7, wherein said recess comprises an elongate channel.

10. A nasal cannula comprising:

a base portion defining a first interior portion;

a nasal insert disposed adjacent said base portion and defining a second interior portion, said first interior portion being in gaseous communication with said second interior portion, wherein:

said nasal insert defines a passageway that is adapted to prevent said nasal insert from creating a seal with a user's nare when the nasal insert is operatively positioned within said nare, said passageway being dimensioned to: (1) allow the user to inhale ambient air through said passageway, when said nasal insert is operatively positioned within said nare; and (2) to allow the user to exhale air through said passageway when said nasal insert is operatively positioned within said nare.

11. The nasal cannula ofclaim 10, wherein said nasal cannula further comprises at least one sensor that is configured for determining the internal environment of the user's upper airway for continuous positive airway pressure.

12. The nasal cannula ofclaim 10, wherein said nasal cannula further comprises at least one sensor that is configured for determining the internal environment of the user's upper airway for high flow respiratory support.

13. The nasal cannula ofclaim 10, wherein said nasal cannula further comprises at least one sensor that is configured to transmit data to a control system that is adapted for: (A) receiving data from said at least one sensor; and (B) adjusting the delivery of respiratory gas to said nasal cannula based on said data.

14. The nasal cannula ofclaim 10, wherein said nasal cannula further comprises at least one sensor that is configured to transmit data to a control system that is adapted for receiving data from said at least one sensor and for issuing an alarm in response to said data satisfying pre-determined criteria.

15. A nasal cannula comprising:

a supply tube defining an interior portion;

a nasal insert defining a therapeutic gas passageway that is in gaseous communication with said interior portion of said supply tube; and

at least one sensor for measuring the properties of gas adjacent said nasal insert.

16. A nasal cannula comprising:

a base portion defining a first therapeutic gas passageway;

at least one nozzle disposed adjacent said base portion and defining a second therapeutic gas passageway, said first therapeutic gas passageway being in gaseous communication with said second therapeutic gas passageway, said at least one nozzle adapted to provide a directed flow of therapeutic gas from said second therapeutic gas passageway and into a particular one of a user's nares when said nasal cannula is operatively positioned adjacent said user's nares; and

an elongate extension disposed adjacent said nozzle, wherein:

said nasal cannula is adapted so that, when said nasal cannula is operatively positioned adjacent said user's nares:

said at least one nozzle is spaced apart from said particular one of said user's nares; and

said elongate extension extends into an interior portion of said particular one of said user's nares.

17. The nasal cannula ofclaim 16, wherein said nasal cannula further comprises at least one sensor for measuring the properties of gas within at least one of a user's nares.

18. The nasal cannula ofclaim 16, wherein said at least one nozzle is sized and shaped to prevent insertion into a user's nare when said at least one nozzle is operatively positioned adjacent said nare.

19. The nasal cannula ofclaim 16, further comprising a stop disposed adjacent said base portion, wherein said stop is positioned to engage a user's columella and prevent insertion of said nozzle into a user's nare when said nozzle is operatively positioned adjacent said nare.

20. The nasal cannula ofclaim 16, wherein said elongate extension lies within said second gas passageway and wherein a distal end of said elongate extension extends beyond a distal end of said nozzle.

21. The nasal cannula ofclaim 16, wherein said at least one sensor is disposed adjacent a distal end of said elongate extension.

22. A nasal cannula comprising:

a base portion defining a first gas passageway;

a nozzle disposed adjacent said base portion and defining a second therapeutic gas passageway, said first gas passageway being in gaseous communication with said second gas passageway, said nozzle being sized and shaped to prevent insertion into a user's nare when said nozzle is operatively positioned adjacent said nare;

an elongate extension disposed adjacent said nozzle and defining a third passageway; and

at least one sensor for measuring the properties of gas adjacent a distal end of said elongate extension.

23. The nasal cannula ofclaim 22, wherein a distal end of said elongate extension is adapted to be disposed adjacent a particular one of said user's nares when said nasal cannula is operatively positioned adjacent said user's nares.

24. The nasal cannula ofclaim 22, wherein a distal end of said elongate extension is adapted to be disposed within a particular one of said user's nares when said nasal cannula is operatively positioned adjacent said user's nares.

25. The nasal cannula ofclaim 24, wherein said sensor is disposed within said elongate extension.

26. A nasal cannula comprising:

a base portion defining a first gas passageway;

at least one nozzle disposed adjacent said base portion and defining a second gas passageway, said first gas passageway being in gaseous communication with said second gas passageway, said at least one nozzle adapted to provide a directed flow of therapeutic gas from said second therapeutic gas passageway and into a particular one of a user's nares when said nasal cannula is operatively positioned adjacent said user's nares; and

a stop disposed adjacent said base portion, wherein said stop is positioned to engage a user's columella and prevent insertion of said nozzle into said particular one of said user's nares when said nozzle is operatively positioned adjacent said user's nares.

27. The nasal cannula ofclaim 26, wherein:

said nasal cannula further comprises an elongate extension disposed adjacent said nozzle; and

said nasal cannula is adapted so that, when said nasal cannula is operatively positioned adjacent a user's nares, said elongate extension extends into an interior of said particular one of said user's nares.

28. The nasal cannula ofclaim 27, further comprising at least one sensor for measuring the properties of gas adjacent said elongate-extension.

29. The nasal cannula ofclaim 28, wherein a distal end of said elongate extension extends beyond a distal end of said nozzle.

30. A system for delivering therapeutic gas to a user, said system comprising:

a nasal cannula that comprises:

a base portion defining a first therapeutic gas passageway,

a nasal insert disposed adjacent said base portion and defining a second therapeutic gas passageway, said first therapeutic gas passageway being in gaseous communication with said second therapeutic gas passageway, and

at least one sensor for measuring the properties of gas adjacent said nasal insert; and

a therapeutic gas delivery control system that is adapted to receive data from said at least one sensor, and to adjust a flow of respiratory gas to said nasal cannula based, at least in part, on said data.

31. The system ofclaim 30, wherein:

said therapeutic gas delivery control system is further adapted for adjusting a flow of respiratory gas through said first and second passageways based on said data.

32. The system ofclaim 30, wherein:

said nasal insert defines a recess that is adapted to prevent said nasal insert from creating a seal with a nare of said user when the nasal insert is operatively positioned within said nare.

33. The nasal cannula ofclaim 32, wherein said recess comprises an elongate groove.

34. The nasal cannula ofclaim 32, wherein said recess comprises an elongate channel.

35. The system ofclaim 30, wherein:

said nasal insert is a first nasal insert;

said at least one sensor comprises a first sensor;

said data is a first set of data; and

said nasal cannula comprises:

a second nasal insert disposed adjacent said base portion and defining a third therapeutic gas passageway, said first therapeutic gas passageway being in gaseous communication with said third therapeutic gas passageway, and

a second sensor for measuring the properties of gas adjacent said second nasal insert.

36. The system ofclaim 35, wherein:

said therapeutic gas delivery control system is adapted for:

receiving a second set of data from said second sensor, and

adjusting said flow of respiratory gas to said nasal cannula, at least in part, based on said second set of data.

37. The system ofclaim 36, wherein said first set of data is a different type of data than said second set of data.

38. The system ofclaim 36, wherein said first sensor is a different type of sensor than said second sensor.

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