NASAL / ORAL SAMPLING CANNULA

Abstract

NASAL / ORAL SAMPLING CANNULA The present invention relates to a nasal cannula (1) comprising a tube (2) configured with a first portion (3) defining an inhalation pathway and a second portion (4) defining an exhalation pathway, the first portion (3) and the second portion (4) being divided by a sealing element (5), the first portion (3) comprising an inlet (6) and a first nosepiece (7) for insufflating gas into a patient's nostril and the second portion (4) comprising an outlet (8), a second nosepiece (9) for recovering exhaled gas from a patient's nostril, and a first pressure build-up releasing means (10) along the exhalation pathway. Figure for abstract: FIG. 2

Description

Title of the invention: NASAL / ORAL SAMPLING CANNULA FIELD OF THE INVENTION

[0001] The present invention relates generally to medical devices, and more particularly to a nasal cannula which alleviates occlusion of nasal nozzles during the insufflation of oxygen gas and the sampling of carbon dioxide gas. BACKGROUND OF THE INVENTION

[0002] When a human patient is ill or undergoing surgery, it is often necessary to supplement the inhalation of the body with a treatment gas, such as oxygen gas or a gaseous anesthetic. In these cases, an accurate quantitative determination of the amount of at least one gaseous component, such as carbon dioxide, in the blood circulating in the pulmonary alveoli of the human patient is highly desirable. Under intensive care conditions or under general anesthesia, an accurate measurement of the composition of the respiratory gas in the pulmonary alveoli makes it easier to monitor a patient's bodily functions and to more favorably adapt the patient's treatment to the state of these functions. Accurate measurements of at least one gaseous component in the exhalation of a human patient can help improve related diagnostic methods for determining bodily conditions.

[0003] One area of ​​particular interest is the monitoring of end-tidal carbon dioxide, which is the partial pressure of the carbon dioxide component of expired gas at the end of expiration in a spontaneously breathing patient. Quantitative monitoring of end-tidal carbon dioxide in spontaneously breathing, non-intubated patients (those who do not require intubation with an endotracheal tube) would be particularly useful for non-intubated patients who, although awake, are being treated with supplemental oxygen and are receiving regional or local anesthesia or are in a recovery room upon recovery from residual general anesthesia.

[0004] Generally, a nasal cannula is used to deliver a flow of gas to a patient through their nostrils or other nasal passages as needed. This device is configured to deliver oxygen into the patient's nostrils or to extract carbon dioxide from them, in order to measure end-tidal carbon dioxide. Nasal cannula assemblies generally consist of an inlet tube, either symmetrical or unilateral, that extends over the upper lip. This tube is extended by a pair of open tips that insert into the patient's nostrils to administer oxygen to him. Nasal cannulas have the advantage of being more comfortable and acceptable than a face mask for most patients. Technologies related to nasal cannula assemblies are generally established and disclosed in the prior art.

[0005] An example of a nasal cannula configured to deliver a fluid stream to a patient is described in U.S. Patent No. US5335656A. The present invention relates to a nasal cannula having a wall member cooperating with a hollow body of the cannula to define inspiratory and exhalation manifolds and sealingly engaging the hollow body to provide a gas-tight seal to positively prevent fluid communication between these manifolds, and a hollow nasal tip projecting from each manifold for receipt in a corresponding nostril of a patient. Another example is described in the surface of a patient's nose to secure the patient interface.Another example is described in US Patent No. US11420002B2 which describes a nasal cannula including a manifold having an inlet port for receiving the fluid flow and at least one outlet port for delivering the fluid flow into the patient's nostrils, a port located on the manifold for delivering a medicament into the fluid flow delivered by the nasal cannula to the patient. US Patent No. US7353826B2 also describes a ventilation interface including a nasal cannula body having a pair of nasal tips located on an upper portion of the nasal cannula body and a bellows-like structure configured to contact a lower surface of the nose to create a sealed interface between the nasal cannula body and the nose.

[0006] Normal nasal cannulas are designed with a slightly smaller outer diameter, which is anatomically desirable to ensure comfort when inserted into the patient's nostrils. This is also important to give the correct direction and flow rate to the gas delivered into the patient's nasal cavities. However, problems can be encountered if the patient is in a horizontal or supine position, which tends to cause a buildup of secretions in the nasal cavities. The problem can be particularly serious if the secretions dry up and obstruct the orifices of the nasal prongs. This eventually blocks the insufflation of oxygen gas or the sampling of carbon dioxide gas. For example, the use of the nasal cannula to monitor end-tidal carbon dioxide gas during the administration of anesthesia. There is therefore a need to provide a nasal cannula that mitigates the incidence of occlusion of the nasal prongs.These nasal cannulas can be useful for sampling carbon dioxide and insufflating oxygen gas. The present invention eliminates and provides a solution to the above-mentioned drawbacks. Summary of the invention

[0007] One aspect of the invention is to provide a nasal cannula for sampling carbon dioxide exhaled from a patient. Advantageously, the nasal cannula of the present invention reduces the incidence of occlusion of the tip of the nasal cavity during withdrawal of carbon dioxide through the nasal cannula to a carbon dioxide monitoring device. This minimizes the risk of falsifying end-tidal carbon dioxide measurements.

[0008] Another aspect of the invention is to provide a nasal cannula for delivering oxygen gas to a patient while accurately monitoring end-tidal carbon dioxide. Ideally, the nasal cannula will resume proper function when either or both of the nasal nozzles become clogged due to the accumulation of nasal secretions.

[0009] At least one of the foregoing objects is achieved, in whole or in part, wherein the embodiment of the present invention describes a nasal cannula comprising a tube configured with a first portion defining an inhalation pathway and a second portion defining an exhalation pathway, the first portion and the second portion being divided by a sealing member, the first portion comprising an inlet port and a first nosepiece for insufflating gas into a patient's nostril, and the second portion comprising an outlet port, a second nosepiece for recovering exhaled gas from a patient's nostril, and a first means for releasing pressure buildup along the exhalation pathway.

[0010] In a preferred embodiment of the present invention, it is stated that the sealing element is a partition wall between the first part and the second part to prevent mixing of gases between the inhalation route and the exhalation route.

[0011] In a preferred embodiment of the present invention, it is stated that the tube further comprises means for recovering a portion of the gas exhaled orally from the mouth of a patient.

[0012] Preferably, the tube includes a channel having an opening and in fluid communication with the exhalation pathway for conveying the portion of the orally exhaled gas to the second portion of the tube.

[0013] In a preferred embodiment of the present invention, the channel further comprises an extended cover portion configured to intercept gas exhaled orally from a patient's mouth and route it to the opening of the channel.

[0014] Preferably, the partition wall is located near the channel and adjacent to the first nasal tip.

[0015] In a preferred embodiment of the present invention, the first means for releasing pressure buildup is at least one opening disposed on the exhalation pathway adjacent the partition wall and aligned with the first and second nasal prongs.

[0016] In a preferred embodiment of the present invention, the first and second nasal tips are each configured with a second means for releasing pressure buildup along the tip.

[0017] Preferably, the second pressure buildup release means comprises one or more openings centrally disposed on an upper surface and a lower surface of the first and second nosepieces.

[0018] Preferably, the inlet of the first portion is configured to be connected to an external oxygen source.

[0019] Preferably, the outlet of the second portion is configured to be connected to a vacuum pump.

[0020] More preferably, the vacuum pump is further coupled to a device for measuring the concentration or partial pressure of a gas exhaled by a patient.

[0021] Those skilled in the art will readily understand that the present invention is well suited to achieve the objects and obtain the purposes and advantages mentioned, as well as those inherent therein. The embodiment described herein is not intended to limit the scope of the invention. Brief description of the drawings

[0022] In order to facilitate understanding of the invention, the accompanying drawing illustrates preferred embodiments, the examination of which, in light of the following description, makes it possible to readily understand and appreciate the invention, its construction and operation, as well as many of its advantages, would be readily understood and appreciated.

[0023] [Fig.l] shows a top perspective view of a nasal cannula according to the present invention.

[0024] [Fig.2] shows a bottom perspective view of a nasal cannula according to the present invention.

[0025] [Fig.3] shows a side perspective view of a nasal cannula of [Fig.l] according to the present invention.

[0026] [Fig.4] shows a side perspective view of a nasal cannula of [Fig.2] according to the present invention.

[0027] [Fig.5] shows a rear view of a nasal cannula according to the present invention.

[0028] [Fig.6] shows a front view of a nasal cannula according to the present invention.

[0029] [Fig.7] shows a cross-sectional view of a nasal cannula according to the present invention, taken along line AA of [Fig.1].

[0030] [Fig.8] shows the inspiration and expiration pathways in the nasal cannula according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0031] The invention will be described hereinafter according to the preferred embodiments of the present invention and with reference to the description and the accompanying drawings. However, it is understood that the limitation of the description to the preferred embodiments of the invention is only intended to facilitate the discussion of the present invention and that a person skilled in the art can conceive of various modifications without departing from the scope of the appended claim.

[0032] The present invention relates to a nasal cannula for use in connection with an oxygen gas source at one end and in connection with a vacuum pump coupled to a carbon dioxide monitoring device at another end. The nasal cannula of the present invention allows oxygen gas to be insufflated into a patient while accurately monitoring end-tidal carbon dioxide.

[0033] [Fig.l] shows a preferred embodiment of the nasal cannula, generally designated by the reference numeral (1), comprising a tube (2) configured with a first portion (3) defining an inhalation pathway and a second portion (4) defining an exhalation pathway. In the context of the present invention, the term "inhalation pathway" refers to a pathway in the nasal cannula (1) through which a medical gas, such as oxygen, is delivered from an oxygen concentrator, an oxygen cylinder or other oxygen supply equipment and directed to the respiratory system of a patient. On the other hand, the term "exhalation pathway" refers to a pathway in the nasal cannula (1) through which carbon dioxide is expelled from the respiratory system of a patient and directed to a device for monitoring carbon dioxide levels.In the preferred embodiment, the first portion (3) of the tube (2) defining the inhalation pathway comprises a first nasal tip (7) for insufflating oxygen gas into the nostril of a patient. In the preferred embodiment, the second portion (4) of the tube (2) defining the exhalation pathway comprises a second nasal tip (9) for recovering exhaled gas, such as carbon dioxide, from the nostrils of a patient. It is understood that the first and second nasal tips (7, 9) are adapted to fit into the corresponding nostrils of a patient.

[0034] A sealing element (5) is sealingly engaged with the inner surface of the interior of the substantially hollow tube (2) and serves as an intermediate transverse barrier dividing the tube (2) into a first portion (3) and a second portion (4). The sealing member (5) may be made of a material substantially impermeable to liquids and gases, thereby preventing fluid communication between the inhalation route and the exhalation route. The nasal cannula (1) of the present invention, as a whole, is preferably molded from a flexible plastic material, the sealing member (5) being integrally molded with the wall of the tube (2), as shown in Figures 1 and 2. However, the sealing member (5) may be a separate barrier sealingly adhered to the wall of the tube (2) by other means, such as an adhesive composition or fusing the material of the sealing member (5) to the material of the tube (2) by solvent welding, sonic welding, or other similar means.In a preferred embodiment of the present invention, the sealing element (5) is a separating wall (11) between the first and second parts (3, 4) of the tube (2), as shown in Figures 1 and 2. In the preferred embodiment, the separating wall (11) is provided to prevent the mixing of oxygen gas and carbon dioxide between the inhalation route and the exhalation route.

[0035] Referring to [Fig.2], the first part (3) of the tube (2) defining the inhalation path can be connected to an external source of oxygen gas (not shown) such as an oxygen concentrator, an oxygen cylinder or any other oxygen supply equipment by a first supply tube (18) through an inlet port (6) which extends and terminates at one end of the first part (3). On the other hand, the second part (4) of the tube (2) defining the exhalation path can be connected to a vacuum pump of a device for measuring the concentration or partial pressure of carbon dioxide (not shown) by a second supply tube (19) through an outlet port (8) which extends and terminates at one end of the second part (4). The first and second feeding tubes (18, 19) are preferably flexible and may be obtained separately or as part of the nasal cannula (1).In this case, an end portion (20) of the first feed tube (18) and an end portion (21) of the second feed tube (19) may be permanently secured by adhesion to corresponding inlet (6) and outlet (8) ports of the tube (2). For example, the ends of the feed tube (20, 21) may be sealed by means similar to those used to seal the sealing member (5) inside the tube (2). On the other hand, if the nasal cannula (1) of the present invention is to be provided without attached feeding tubes, the tube (2) is preferably made of a more elastic material than the feeding tube ends (20, 21) so that the force required to seat the feeding tube ends (20, 21) will ensure an airtight engagement between the respective feeding tube ends (20, 21) and the inlet port (6) and outlet port (8).

[0036] To ensure maximum sampling of exhaled gases from a patient's respiratory system, it is ideal to recover, to some extent, a portion of the orally exhaled gas from a patient's mouth to monitor and measure carbon dioxide. Referring to Figures 1 - 4, the tube (2) of the nasal cannulas (1) of the present invention comprises means for recovering a portion of the orally exhaled gas (12) from a patient's mouth. In the context of the present invention, the orally exhaled gas comprises carbon dioxide. The means for recovering a portion of the orally exhaled gas (12) comprises a channel (13) having an opening (15) and an extended cover portion (14) integrally disposed over the channel (13).As shown in Figures 4 and 6, the channel (13) extends in a transverse direction of the tube (2) and in fluid communication with the exhalation path of the second part (4) for conveying the portion of the gas exhaled orally from the mouth of a patient to the second part (4) of the tube (2). Referring to Figures 1 and 2, in proximity to the channel (13) is the partition wall (11) which separates the first and second parts (3, 4) of the tube (2). The partition wall (11) is also located in proximity to the first nasal tip (7). Such positioning of the partition wall (11) provides an optimal space for the arrangement of the channel (13) in fluid communication with the exhalation path of the second part (4).In a preferred embodiment of the present invention, the channel (13) further comprises an extended cover portion (14), as indicated above, which is adapted to be positioned proximate the mouth of a patient in order to intercept orally exhaled gas and to pass at least a portion of the orally exhaled gas towards the opening orifice (15) of the channel (13). The interception of orally exhaled gas from the mouth of a patient is made possible by the inwardly curved shape of the extended cover portion (14), as shown in [Fig. 4]. The channel (13) is also shown in [Fig. 1] illustrated by dotted lines, indicating that the view of the channel (13) is obstructed by the extended cover portion (14), which is disposed thereon. As shown in [Fig.7], the opening orifice (15) of the channel (13) allows gas exhaled orally through the mouth of a patient to be received and conveyed into the second part (4) of the tube (2) by means of an air passage (16) located inside the channel (13).

[0037] When using a conventional nasal cannula, insertion of the nasal tips into the nostrils should not cause irritation or discomfort to the patient. However, some patients may be more sensitive than others, and prolonged insertion of nasal tips into a patient's nostrils can potentially lead to irritation of the nasal passages, for example when the patient is in a horizontal or lying position. Nasal irritation causes the secretion of nasal fluids into the nostrils, the accumulation of which could inevitably obstruct the nasal nozzles. Occlusion of the nasal nozzles can increase the pressure in the nasal cannulas and prevent their proper functioning. In order to mitigate or eliminate the incidence of occlusion of the nasal nozzles, the second portion (4) of the tube (2) of the nasal cannulas (1) includes a first pressure build-up release means (10) along the exhalation pathway. As can be generally seen in Figures 1 - 4, the first pressure build-up release means (10) is at least one opening disposed on the exhalation pathway of the second portion (4) of the tube (2). The operating mechanism of the first pressure build-up release means (10) is best illustrated in [Fig.8]. In the event that the second nasal nozzle (9) is obstructed, the pressure build-up due to carbon dioxide in the exhalation path of the second part (4) of the tube (2) can be released by opening the first pressure build-up release means (10).When using a vacuum pump connected to the outlet port (8) of the second part (4), the pressure built up along the exhalation path can be vented through the opening (10) provided for this purpose. Optionally, one or more openings (10) can be provided along the exhalation path. In addition, carbon dioxide exhaled through the nostrils of a patient can be received through the opening (10) when the outlet port (8) of the second part (4) is connected to a vacuum pump, as shown in [Fig. 8]. Referring to [Fig. 5], the inlet port (10) is located along the second part (4) of the tube (2). Preferably, the opening (10) is located opposite the channel (16) or close to the partition wall (11). Preferably, the opening (10) aligns parallel to the first and second nasal tips (7, 9).

[0038] In the present invention, a second pressure buildup releasing means (17) is provided to mitigate the incidence of occlusion of the first and second nasal prongs (7, 9). In a preferred embodiment of the present invention, the first and second nasal prongs (7, 9) are each configured with a further opening (17) for releasing pressure buildup therealong, as shown in Figures 1 and 2. Each of the openings (17) is centrally disposed on an upper surface and a lower surface of the first and second nasal prongs (7, 9). Similarly, carbon dioxide exhaled from a patient's nostrils may be received through the opening port (17). On the other hand, in the event that the first nasal nozzle (7) is obstructed, opening the second pressure release means (17) allows the administration of oxygen gas into the nostril of a patient, as shown in [Fig.8].

[0039] The present description includes what is contained in the appended claims, as well as in the foregoing description. Although this invention has been described in its preferred form with a certain degree of precision, it is to be understood that the present description of the preferred form has been made only by way of example and that numerous changes in the details of construction and in the combination and arrangements of parts may be made without departing from the scope of the invention.

Claims

Claims

1. A nasal cannula (1) comprising: a tube (2) configured with a first portion (3) defining an inhalation pathway and a second portion (4) defining an exhalation pathway, the first portion (3) and the second portion (4) being divided by a sealing member (5); the first portion (3) comprising an inlet port (6) and a first nosepiece (7) for blowing gas into a patient's nostril; and the second portion (4) comprising an outlet port (8), a second nosepiece (9) for recovering exhaled gas from a patient's nostril, and a first pressure buildup releasing means (10) along the exhalation pathway.

2. A nasal cannula according to claim 1, wherein the sealing member (5) is a partition wall (11) between the first part (3) and the second part (4) to prevent mixing of gases between the inhalation route and the exhalation route.

3. A nasal cannula according to claim 1, wherein the tube (2) further comprises means for recovering a portion of the orally exhaled gas (12) from a patient's mouth.

4. A nasal cannula according to claim 3, wherein the tube (2) comprises a channel (13) having an opening (15) and in fluid communication with the exhalation pathway for conveying the portion of the orally exhaled gas to the second portion (4) of the tube (2).

5. The nasal cannula of claim 4, wherein the channel (13) further comprises an extended cover portion (14) configured to intercept orally exhaled gas from a patient's mouth and pass it toward the opening (15) of the channel (13).

6. A nasal cannula according to any one of claims 2 to 5, wherein the partition wall (11) is located proximate to the channel (13) and adjacent to the first nasal tip (7).

7. A nasal cannula according to claim 1, wherein the first pressure build-up release means (10) is at least one opening disposed on the exhalation pathway adjacent the partition wall (11) and aligned with the first and second nasal tips (7,9).

8. A nasal cannula according to claim 1, wherein the first and second nasal tips (7, 9), are each configured with a second pressure build-up release means (17) therealong.

9. A nasal cannula according to claim 8, wherein the second pressure build-up release means (17) comprises one or more openings centrally disposed on an upper surface and a lower surface of the first and second nasal tips (7,9).

10. A nasal cannula according to claim 1, wherein the inlet port (6) of the first part (3) is configured to be connected to an external oxygen source.

11. A nasal cannula according to claim 1, wherein the outlet orifice (8) of the second part (4) is configured to be connected to a vacuum pump.

12. The nasal cannula of claim 11, wherein the vacuum pump is further coupled to a device for measuring the concentration or partial pressure of a gas exhaled by a patient.

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