WO2002092156A1

WO2002092156A1 - Nasal cannula assembly and securing device

Info

Publication number: WO2002092156A1
Application number: PCT/US2001/015679
Authority: WO
Inventors: Gloria Argraves
Original assignee: Gloria Argraves
Priority date: 2001-05-14
Filing date: 2001-05-14
Publication date: 2002-11-21
Also published as: CA2390977A1

Abstract

A device for securing a nasal cannula to a patient's head is disclosed. The device utilizes a thin round elastic band placed behind the patient's head and is attached to the cannula gas supply tube (20) by cord couplers (30, 35). The cord couplers (30, 35) are slidably attached to the gas supply tubes (20) to allow fast and easy adjustment to size. The device is light, comfortable, inexpensive and simple to use. It prevents painful hair entanglement and allows single handed deployment and adjustment of a nasal cannula, while affording secured placement of the cannula during patient movement or sleep. Additionally, a nosepiece (10) having a downwardly oriented U shape or arcuate fold in its center portion is disclose to prevent the cannula nosepiece (10) from exerting excessive pressure against the patient's septum. A method of use is also disclosed.

Description

Nasal Cannula assembly and securing device.

Field of the invention

This invention relates in general to nasal cannulas, and more particularly to a securing a nasal cannula at a desired position on a patient and an improved nosepiece. Background

Nasal cannulas are well known in the art, and are typically characterized by US patent 4,106,505 to Salter et al. Cannulas are frequently used to alleviate respiratory distress due to many types of respiratory medical conditions by supplying an oxygen enriched air stream to a patient. Often wearing the cannula on a 24 hour a day basis is a medical necessity. The use of a nasal cannula allows the patient freedom of movement and activity, while being unobtrusive as compared to the larger and bulkier facemasks.

A nasal cannula comprises essentially a nasal assembly, or nosepiece, with a hollow main body having two directed orifices near or in a patient nostrils. The gas is supplied to the main body that acts as a distributing manifold. Typically, the orifices are placed at the end of nasal extension tubes extending upwardly from a main body portion and in communication with the main body. Commonly two gas supply tubes are attached to the cannula nosepiece, that is held in place by extending the gas supply tubes from the patient's nasal area behind the patient's ears. The flexible tubes are bent downward behind the ears to run generally along the jaw area, and are held in place by an adjustable slip loop or a cinch tightened below the chin to hold the nosepiece in place. Oxygen or other gas flows through the tube to the two orifices, and the gas is mixed with the air stream of the patient air intake.

While being one of the most convenient methods known to date for supplying a patient with a gas enriched environment, nasal cannulas suffer a major drawback: the positioning of the tubes around the ears for support is uncomfortable and is prone to falling off the patient's face. Additionally, it causes the patient chaffing and pain. Patients regularly find that body movement, especially during sleep, causes the cannula to dislocate, depriving the patient of the needed oxygen enrichment. Accidental removal of the cannula often causes severe discomfort to the patient and in certain cases may even be life threatening. US patents 5,636, 630 to Miller et al., US patent 4,836,200 to Clark, and US patent 4,422,456 to Tiep, all attempt to solve this problem. Miller et al. discloses running the tubes behind the patient head and utilizing a coupling portion contacting the back of the head, with the gas conduits passing in criss-cross manner behind the head. This arrangement suffers from several disadvantages, major amongst them is the location of both oxygen tubes behind the patient's head where they may be blocked if the head is resting thereupon. Additionally, placement of tubes behind the head is often uncomfortable to the patient.

The Clark patent utilizes a pressure-fastening strap adapted to go over the top of a user's head, onto which the flexible tubes are attached. Clark also discloses and teaches away from a strap wrapped completely around the head, with separate attachment means for the flexible tubes. Clark's preferred implementation is less desirable since the strap may slide over the head of the user and is liable to entangle with the patient's hair. Tiep's patent discloses means for supporting the cannula in place by an elastic band that is adjustably connected to two holders each located on one of the conduits or flexible tubes. Each of the holders includes a band fitting around the conduit and in frictional engagement with it, and a tab attached to the band so as to extend generally along the conduit. An elastic band extending behind the patient's head is secured to the tab by being threaded through openings within the tab. Two problems arise from the Tiep patent: First, a structure according to Tiep requires threading adjustment of the elastic band. This is time consuming, and when done on a patient head also runs the risk of entanglement in the patient's hair. This problem is especially significant to nurses in a hospital where time is often of the essence. Additionally, an elastic band, being flat in cross section, runs the risk of entanglement in the patient's hair.

In US patent 4,406,283, Bir discloses an oxygen cannula mounting member comprising fabric which is located at the crown of the head with portions extending towards the anterior of the head and terminating with mounting sections. Similarly, in US patent 5,704,916, Byrd describes a strap positionable across the top of the patient's head for supporting a cannula. In a similar, over the head fashion, Odom teaches in US 5,645,058 a cap with support for medical tubing. All the above described examples teach, show, or describe a flat, wide support member or a cap, apparently to better distribute the load of the cannula on the patient's head. All those solutions suffer from being prone to hair entanglement, and are aesthetically obtrusive. In use, typically the nosepiece of a cannula is placed against the nasal septum, and tension is applied against it to secure the nosepiece in place. The tension exerted against the septum causes severe discomfort to some patients, especially during respiratory or medical conditions such as allergies and cold. Soft and flexible materials are commonly used in the construction of nasal cannulas, but the pressure on the soft tissue surrounding the nasal septum stems from the tension necessary to hold the nasal cannula in place.

It is clear therefore that a need exists for a device to secure a nasal to a patient's head in a light, inexpensive, and effective manner, and doing so in a manner that will be unobtrusive to the patient. Additionally, a better solution is needed for providing user comfort in the nasal septum area as described above. The current invention discloses such a device and method for its use.

Summary

It is therefore an objective of the current invention to provide means for securing a gas supply cannula to a patient wearing it so as to insure continuous and uninterrupted supply of oxygen as needed, thus avoiding the discomfort stemming from having to place gas supply tubing behind the patient's ears, or a tight cinch under the patient's neck.

The current invention is based on the discovery that using a flexible elastic cord 40 of generally round cross section and having a relatively small diameter, preferably no larger than one or two millimeters, is uniquely suitable for securing the cannula with only minor inconvenience to the patient. It was found that the use of such round, small diameter elastic cord in combination with other aspects of the current invention, solves the problem of user comfort, visual aesthetics, and skin and hair entanglement, all while ensuring a secure and comfortable method of affixing the nasal cannula in place. Contrary to the apparently common assumption shown by the attempts at the problem described above, that a wide, generally flat construction will reduce patient discomfort, the present invention shows the unexpected discovery that a generally round, small diameter cord extend behind the patient's head provides patient comfort, avoids hair entanglement, and is hardly visible.

It is also an object of this invention to provide for easy, fast, and single-handed adjustment of the cannula in place to permit easy adjustment for different head dimensions. To that end, a cord coupler 30 and 35 is also disclosed herein. The cord coupler is in slidable engagement with the flexible gas supply tubes 20 and 25 supplying oxygen to the cannula nosepiece 10. The elastic cord 40 is attached to the cord couplers 30 and 35, that in turn couples the cord to the gas supply tubes 20 and 25. In the preferred implementation, two cord couplers are utilized, made of flexible tubing with an inner diameter slightly larger than the outer diameter of the gas supply tubes. The cord is attached to the cord couplers in any convenient manner. The simplest form of a cord coupler comprises a loop formed the cord around the gas supply tube and tied or otherwise bonded against it in a slidable engagement. In use, the first end of the cord is coupled to one of the two gas supply tubes, and the second end of the cord is coupled to the other gas supply tube. At least one end is coupled by means of a cord coupler as described above. By placing the nosepiece next to a patient's nostrils, and by placing the elastic cord behind the patient's head so it rests against the back portion of the head, the nasal cannula is secured in place. The gas supply flexible tubes are extended towards the patient's ears. At least one of the cord couplers is slidably adjusted forward towards the nosepiece in order to achieve a comfortable fit of the cannula while securing it in place. Thus the cord couplers support the flexible gas supply tubes and the tubes rest on opposite sides of the patient's face, and may be bent downwardly behind the cord couplers and thus avoid the patient's ears altogether. The gas supply tubes generally run down along the jaw area to a meeting point under the patient's neck, but without requiring a cinch to hold them tight against the neck. However any convenient routing of the gas tubes is acceptable since only the portion of the tube between the cord coupler and the nosepiece take part in securing the nosepiece in place. Thus routing of the tubes behind the patient's head allows patients to carry babies or pets in their arms, while still ensuring secure mounting of the cannula against prying little hands or paws. Additionally, when the supply tubes are routed behind a patient's head and down the patient's back, the cannula is less visible and thus the unaesthetic effect is reduced. Thus one aspect of the invention contemplates a nasal cannula having a nosepiece connected to a first and a second gas supply tubes, a cord coupler Adapted for slidable engagement with said first gas supply tube, an elastic cord having a first and a second end, the first end being coupled to said cord coupler, and the second end adapted to couple to the second gas supply tube, wherein said elastic cord having a generally round cross section having a diameter smaller than seven millimeters.

An additional advantage of the present invention is providing the patient with the ability to route the gas supply tubes behind his/her head, without the tubes interfering with the ears. Several advantages are gained by routing the gas supply tubes towards the back of the head, including the freedom of using eye glasses and earphones, are other devices that mount in the ear area. Another advantage is relative immunity to puling of the tube by pets, small children, etc. Yet another advantage is the reduced visibility of the cannula as compared with routing he tubes in front of the patient.

It is yet another object of the current invention to relieve the pressure exerted by the nosepiece main body on the nasal septum area. The invention achieves this goal by a septal pressure relief 90 comprising a valley portion or depression in the nosepiece main body. The valley portion is formed or otherwise introduced in the central segment 15 of the main body interposed the two orifices or nasal extension tubes 13 and 17. The valley may be in the form of a bend, a notch, a curve, v or square shaped notch, a downwardly oriented, generally U shaped depression, or any other shaped depression in the upper surface of the nosepiece main body, causing the main body to deflect away from the patient's septum. The valley avoids or minimizes direct contact between the main body and the nasal septal area. The tension is thus transferred to the softer tissue of the lower portion of the outer nostril walls. Since the outer nostril wall is not supported by a bone, it offers a more convenient support for the nosepiece. Clearly, the septal pressure relief and the securing device disclosed herein may be utilized in combination or separately in a nasal cannula.

The cannula securing means disclosed herein may be made as an attachment to an already manufactured oxygen supply nasal cannula or may be embedded into the cannula manufacturing process. Brief description of the drawings

Fig. 1 depicts a perspective view of a patient using a preferred implementation of the current invention.

Fig. 2 depicts a frontal view of a patient's head while using the invention and showing a preferred implementation wherein the tubes run anteriorily to patient ears.

Fig. 3 depicts a nasal cannula nosepiece with septal pressure relief in accordance with a preferred implementation of the invention.

Fig. 4 shows a preferred implementation of a cord coupler in accordance with the current invention.

Fig. 5 is a side view of an embodiment with the gas supply tubes routed behind the patient's head.

Fig. 6 is a rear view showing gas supply tubes routed behind patients' head.

Detailed Description In the preferred implementation the invention utilizes a round elastic cord attached to cord couplers30 and 35. The elastic cord 40 may be of round or elliptical construction but experiments have shown the generally round cross section to be the preferred implementation. The most preferred cord is composed of rubber or other elastic polymer, and is approximately one (1) millimeter in diameter, since this size has proven to be least prone to entanglement in the patient's hair while producing sufficient mechanical strength. While larger diameter may work as well, a cord diameter above approximately seven millimeters suffers from some or all of the disadvantages of prior attempted solutions. In general, any cord having a diameter less than three millimeters is preferred for practicing the invention. In one preferred implementation, the cord 40 is approximately 30 centimeters in length, however this dimension may be varied to any desired length to fit varying head sizes.

The preferred implementation uses two slidable cord couplers, 30 and 35 respectively, however only one may be used if so desired for reduced cost. For clarity this disclosure will concentrate on a single cord coupler, 30 with an understanding that a similar cord coupler 35 may correspondingly be used on the opposite side of the patient's head. The most important deciding criteria demanded from the cord coupler 30 being a sliding attachment of sufficient friction to hold the cannula nasal assembly 10 in place, while allowing fast and easy adjustment of the elastic cord 40. Other preferable requirements from the cord coupler are that it will be easily adjustable along the length of the gas supply tube 20, and be able to exert enough force thereupon to maintain positive engagement so as to keep the nosepiece 10 in place, without choking the gas supply tube in a manner that may restrict gas flow therein.

The cord coupler 30 in the preferred implementation is constructed substantially of a cord coupler tube: a short piece of flexible tubing of about ten to fifteen (10-15) millimeter in length, however this length may be varied at will. The internal diameter of the cord coupler tube is large enough to fit over the cannula gas supply tube 20, which is at least partially disposed within the cord coupler tube. In the preferred implementation, the elastic cord 40 is passed through a hole 32 or an opening in the sidewall of the cord coupler tube. The elastic cord is held in place by an enlargement of the cord diameter so as to prevent it from sliding out of the hole. Such enlargement may be made by melting the cord end, glue, a bid, a knot tied near the cord's end, or any other conventional measure. Alternatively any other convenient attachment method, such as glue, heat weld, integral molding, pressure fit, attachment sleeve, knot, a combination of any of the above, or any other well known attachment method may be used to attach the elastic cord 40 to the cord coupler 30. Preferably, the cord couplers and the elastic cord are attached to the nasal cannula during manufacturing, but it may also be fitted to an existing cannula.

It will be clear to a person skilled in the art that other implementations of the cord coupler 30 are possible without detracting from the spirit of the invention. Such other implementations include, but are not limited to, a cylinder, a cloth loop, a clip adapted to accept the gas supply tube without pinching it, a molded cylindrical tube holder, or a loop formed in the elastic cord 40 around the cannula gas supply tube 20, and forming a slidable attachment with it. It should be mentioned however that any such attachment method of the elastic to the gas supply tube should be made with consideration towards the aims and requirements mentioned above.

The described method shown in Fig. 4, in which the elastic cord 40 is passed through a hole 32 in the cord coupler tube sidewall with the cord's end being enlarged, has an added advantage. This method reduces the risk of choking the tube while supplying pliable pressure of the gas supply tube against the opposite inner side of the cord coupler tube sidewall.

While the preferred embodiment utilizes two slidable cord couplers 30 and 35, one end of the cord may be permanently attached to one gas supply tube, while the other end having a cord coupler to adjust the elastic cord to size. Such arrangement however, is considered less comfortable to the patient.

In use, the cannula is placed generally with the nosepiece 10 near the patient's nostrils, and the elastic cord 40 is placed behind the patient's head. The two slidable cord couplers 30 and 35 are than slide forward along the gas supply tubes 20 and 25 towards the nosepiece to provide the desired tension and to secure the cannula in place.

The preferred implementation also includes an improved nosepiece 10 having a septal pressure relief. The septal pressure relief, generally designated numeral 90 in Fig. 3, comprises primarily of a downwardly extending valley portion formed in the central segment 15 of the nosepiece 10. The valley portion comprises a generally U shaped, downwardly arcuate fold segment, formed or molded within the central segment of the main body of the cannula nosepiece and preferably integral thereto. The arcuate fold segment is interposed between the nostril extension tubes 13 and 17, and is formed hollow to allow the nosepiece main body to continue functioning as a gas distribution manifold. The downward arcuation of the segment allow transfer of most if not all of the tension normally exerted on the patient nasal septum area to the lower portion of the outer nostril walls, and to the patient's nasalabidial area.

While there have been described what are at present considered to be the preferred embodiments of this invention, it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from the invention and it is, therefore, aimed to cover all such changes and modifications as fall within the true spirit and scope of the invention, for which letters patent is applied.

Claims

What is claimed is:

1. A device for securing a nasal cannula, comprising: a nasal cannula having a nosepiece (10) connected to a first and a second gas supply tubes (20 and 25); a cord coupler (30) Adapted for slidable engagement with said first gas supply tube (20); an elastic cord (40) having a first and a second end, the first end being coupled to said cord coupler, and the second end adapted to couple to the second gas supply tube; and, wherein said elastic cord having a generally round cross section having a diameter smaller than seven millimeters.

2. The device of claim 1 further comprising a second cord coupler (35) in engagement with said second gas supply tube (25), and wherein the second end of said elastic cord is adapted to couple being coupled to said second gas supply tube by means of said second cord coupler.

3. The device of any preceding claim, wherein said cord coupler (30 or 35) is constructed of a cylinder having an internal diameter to provide slidable fit over said flexible tube, and wherein said gas supply tube is being at least partially disposed within said cylinder.

4. The device of claiml or 2, wherein said cord coupler (30 or 35) comprises a tube and wherein said gas supply tube is being at least partially disposed within said cord coupler tube.

5. The device of any preceding claim, wherein the tube of said first or second cord coupler tubes are flexible.

6. The device of claim 1 wherein said cord coupler (30 or 35) comprises a loop formed in said elastic cord, to encircle one of said gas supply tubes.

7. A device for securing a nasal cannula to a patient's head comprising: a nasal cannula having a nosepiece (10) connected to a first and a second gas supply tubes (20 and 25); a first cord coupler (30) adapted to slidably attach to said first gas supply tube (20) and a second cord coupler 35) adapted to slidably attach to said second gas supply tube (25); and, a flexible elastic cord (40) having a first end and a second end, the first end being affixed to said first cord coupler, and the second end being attached to the second cord coupler; wherein said elastic cord being constructed to have a generally round cross section having a diameter smaller than seven millimeters.

8. The device of any preceding claim, wherein said elastic cord having a diameter less than three millimeters.

9. The device of any preceding claim, wherein said elastic cord having a diameter of approximately one millimeter.

10. The device of any preceding claim wherein said nosepiece (10) also having a downwardly arcuated hollow central segment (15).

11. In a nasal cannula having a hollow nosepiece (10) with a central segment (15) interposed between nasal orifices (13, 17), a spetal pressure relief comprising a downwardly extending valley portion foπned in said central segment.

12. The septal pressure relief of claim 14 wherein said valley portion is a hollow arcuated central segment

13. The septal pressure relief of claim 14 wherein said valley portion is formed generally in a U shape.

14. A method for securing a nasal cannula having two gas supply flexible tubes to a patient's head comprising: placing a nasal cannula nosepiece (10) adjacent to a patient's nostrils; placing an elastic cord (40) behind the back portion of a patient's head, said elastic cord having a generally round cross section and also having one end thereof coupled to the first gas supply tube (20), and having a cord coupler (35) attached to the second end of the elastic cord , wherein said cord coupler is also coupled to the second gas supply tube (25); and, adjustably sliding said cord coupler to secure said cannula to said patient . -il¬

ls. The method of claim 14 wherein said cord is slidably coupled to said first gas supply tube.

16. The method of claim 14 or 15 wherein said elastic cord having a diameter smaller than seven millimeters.

17. The method of claim 14 or 15 wherein said elastic cord having a diameter smaller than three millimeters.

18. The method of any of claims 14 through 17, wherein said nosepiece (10) also having a downwardly arcuated hollow central segment (15).

19. The device of any of claims 1 through 14 wherein said elastic cord (40) is coupled to said cord coupler (30 or 35) by an attachment method selected from glue, heat weld, integral molding, pressure fit, attachment sleeve, knot, or a combination thereof.