GB1562066A

GB1562066A - Gas delivery face shield

Info

Publication number: GB1562066A
Application number: GB487278A
Authority: GB
Original assignee: Hudson Oxygen Therapy Sales Co
Current assignee: Teleflex Medical Inc
Priority date: 1978-02-07
Filing date: 1978-02-07
Publication date: 1980-03-05

Description

(54) GAS DELIVERY FACE SHIELD (71) We, HUDSON OXYGEN THERAPY SALES COMPANY, a corporation organised under the laws of the State of California, U.S.A. of 27711 Diaz Street, Temecula California, U.S.A. do hereby declare the invention for which we pray that a Patent may be granted to us and the method by which it is performed to be particularly described in and by the following statement: This invention is concerned with the provision of an improved face shield for delivering gas to a patient.

Oxygen masks have been known and used for some time as efficient means for delivering oxygen to a patient during inhalation or respiratory therapy. More recently, these masks have been made of relatively soft and flexible plastics material thereby making them disposable for single patient use. The modern and efficient masks have also been constructed so as to have a peripheral edge surface for fitting entirely around the patient's nose and cheeks, with the shorter masks passing beneath the patient's mouth along the chin and the longer masks extending under the patient's chin, but all in substantial sealing engagement so as to prevent loss of the oxygen containing gas delivered through the mask. Although such masks deliver the oxygen-containing gas with desirable efficiency, since they are in substantial sealing engagement with the patient's face substantially entirely around the mask periphery, they offer some disadvantages.

For example, the masks may become uncomfortable to the patient because of the extensive contact with the patient's face and also because of heat build up within the entirely enclosed mask area. In addition, CO2 build up is often a problem in masks of this type which results in significant limitations of the upper end of oxygen delivery concentrations possible.

Further, because such a mask encloses the patient's lower face area, in order for the patient to speak or to take in food through the mouth, the mask must be removed or at least temporarily lifted which causes further discomfort and possible patient aggrevation or anxiety. Obviously during the time that the mask is removed, oxygen delivery to the patient is interrupted.

Of further concern is the possibility of a patient choking where fluids such as vomitus are aspirated from the enclosed mask area. Moreover, because the state of the art oxygen delivery masks require close fit about and around the patient's face in order to prevent leakage and achieve the intended and desired oxygen concentrations, the positioning of the mask and maintaining that position on the patient is quite important. If the mask becomes loosened or significantly moved, the sealing engagement of the mask edge with the patient's face will be disturbed thereby allowing undesirable venting of exterior ambient air into the mask as well as loss of oxygen and concomitant change in the oxygen concentration delivered to the patient, which may not be monitored. It is to the elimination and obviation of these disadvantages of state of the art masks that the device of the present invention is directed.

According to the present invention there is provided a face shield for delivering gas to a patient during respiratory therapy and adapted to be secured over the patient's nose and mouth comprising: a unitary shape-retaining shell member having an upper peripheral surface adapted for lying against the patient's cheeks and across the nose bridge and a lower edge which, when said device is secured on a patient, forms a space between the face of the patient and the shield, and a gas delivery member extending along the shell interior and having at least one gas delivery orifice therealong.

Preferably the lower part of said shell member is arched outwardly in relation to a patient's face.

The upper peripheral surface of the shell is preferably adapted to provide a substantially gas tight seal with the patient's nose bridge and cheeks to prevent gas from being directed to the eyes.

The gas delivering face shield device of the present invention offers a number of advantages over known oxygen delivery masks. For example, although the device is in sealing engagement around the patient's nose and cheeks so as to prevent oxygen from being directed upwardly into the patient's eyes resulting in discomfort or eye injury, the bottom of the shield around the patient's mouth is entirely open thereby preventing heat build up, presenting fewer pressure points or points of contact of the mask with the patient's facial skin, allowing the patient to talk more freely than an entirely enclosed mask, and also providing for the patient to take food or at least to be straw fed through the mouth without removing the shield or otherwise interrupting the desired oxygen delivery and concentrations. The device of the invention is relatively simple, comprising a unitary face shield in the preferred form of an arched shell and incorporating an oxygen delivery tube or pipe having a plurality of gas delivery orifices and which pipe is extended along the interior shield surface, preferably below the patient's nares. The features and characteristics of the device as well as additional advantages will be evident from the following detailed description.

In this specification when reference is made to upper and lower parts the upper part refers to the part adjacent to the nose of a user and the lower part refers to the part adjacent to the chin of a user.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a perspective view of an oxygen delivering face shield constructed according to the invention showing it in place on a patient; Figure 2 is a front view of the face shield shown in Figure 1; Figure 3 is a sectional elevation of the face shield taken along lines 3-3 of Figure 2; Figure 4 is a top view of the gas delivery pipe utilized in the face shield; and Figure 5 is a partial sectional view illus trating another embodiment of the face shield and gas delivery orifices.

DETAILED DESCRIPTION OF THE INVENTION Figure 1 illustrates the face shield 10 which comprises a unitary shell member 16 and a gas delivery member 20. As illustrated, the shell member is arched outwardly away from the patient's face and is divided into an upper portion 14 and lower portion 12 between which is located the gas delivery pipe 20. It should be appreciated that the shell member 16 is a unitary component, preferably molded of a single plastics sheet. However, in the preferred embodiment shown, the upper and lower shell portions are shaped somewhat differently and are separated by the gas delivery pipe.

Figures 2 and 3 illustrate the device in more detail, Figure 2 illustrating the upper shell portion 14 having a peripheral edge surface which lies against the patient's face, particularly over the nose bridge and down the cheeks on both sides of the nose.

The arched shell is formed between peripheral side edges and is bowed or arched away from the face and defines an interior cavity 31 into which gas from the delivery pipe is discharged for patient inhalation. The lower shell portion 12 forms a shield or skirt which overlies the patient's mouth and chin and is spaced outwardly from the patient's face so that there is no contact of this lower portion with the patient. Instead, as seen in Fig- ures 1 and 3, the lower portion extends outwardly from the patient's mouth and chin area to also form an interior space or cavity 37. Such a space offers one of the specific and important advantages of the invention in allowing the patient to comfortably exhale and to speak and be easily heard without the mask entirely closing the nose and mouth area. Moreover, because the peripheral edge 33 of the lower shell portion is also arched or bowed away from the patient, an enlarged port or opening 25 is provided between the patient and the shell, which port communicates directly with the interior shell cavities. Accordingly, the inside of the device is open to the environment so that CO2 and heat build up are minimized as well as allowing the patient to be fed at least through a straw without having to remove the mask or otherwise disturb the delivery of oxygen.

Figure 3 also illustrates the preferred attachment of the oxygen gas delivery pipe 20. The pipe is preferably received in a channel 30 defined between a pair of ribs 32 and 34 extending arcuately along the interior surface of the device. These ribs are integrally formed as part of the device and the gas delivery pipe is simply urged into the channel at the time of assembly.

The ribs are preferably spaced apart so that the pipe is forced therebetween with the ribs acting as support walls. Further, the ribs, channel and pipe are conveniently located between the upper and lower shell portions.

The gas delivery pipe 20 is shown in more detail in Figure 4. Preferably the pipe is molded from a more rigid material than that used to prepare the upper and lower shell portions. One end of the gas delivery pipe is provided with a inlet member 18, having a length sufficient to adequately attach a gas supply tube 35. At the other pipe end is a button 22 or similar member for assisting in securing the pipe in position. Accordingly, the shell member preferably has a pair of openings or holes, oppositely disposed and on each side, one for receiving the gas inlet member 18 and the other the button 22.

Since the shell member is prepared from a softer, resilient and flexible plastics such as PVC or the like, button 22 may be oversized relative to the orifice through which it extends and have a groove or slot formed along the button so that the smaller orifice edges can fit into the slot once the button has been pushed through. This or any similar or equivalent means for securing the gas delivery pipe may be used. Again, channel 30 further assists in supporting and fixing the gas delivery pipe within the shell interior surface, with the pipe beng pressed or otherwise urged between the two ribs forming and defining the channel. Although gas inlet member 18 is shown positioned at one end of pipe 20, it may be instead located anywhere along the pipe, for example, in the middle of the shell. In addition, the ends of the pipe may be inset somewhat from the side shell edges to avoid any patient discomfort. An alternative means for supplying oxygen to the pipe comprises using a gas inlet member at both ends of pipe 20, with a gas supply tube connected to each inlet member. Such supply tubes may be extended over the patient's ears to assist in keeping the shield in place on the patient, or may be drawn together under the patient's chin.

The gas delivery pipe is provided with a plurality of openings or orifices 36 through which oxygen-containing gas is delivered within the shield for patient therapy. Figures 1 and 3 further illustrate the disposition of pipe 20 relative to the patient's nostrils and mouth. Since the pipe is of arched or arcuate shape to conform to the arched shell interior surface, it is disposed below or lower than the patient's nares throughout most of its length. Accordingly, it is preferred that the orifices 36 be positioned so as to direct oxygencontaining gas toward the patient and at least somewhat upwardly toward the nares.

Moreover, in a preferred embodiment, oxygen delivery pipe 20 is also provided with a plurality of gas delivery orifices 42 which direct a portion of the oxygencontaining gas toward the patient's mouth or lower part of the shield. The purpose for such downwardly gas directing orifices is to insure that a sufficient supply of oxygen containing gas will be delivered to the patient even if the person is breathing from his or her mouth. Foe example, if the patient's nasal passageway is occluded or the patient is otherwise breathing from the mouth, with all of the oxygen containing gas being directed upwardly, the desired concentrations of oxygen may not be inhaled by the patient because the shell is open at the bottom. The specific number of orifices may be varied widely depending on orifice sizes used, oxygen flow rates, etc. Normally, it is more desirable to incorporate more upwardly directing orifices, preferably between about 4 and 20, with downwardly directing orifices numbering between about 2 and 8.

Figure 3 illustrates another important feature of the invention, specifically the gas sealing engagement of the shell member at the patient's nose and cheek area. The upper shell end 26 is arch shaped to comfortably overlie the patient's nose bridge. Optionally, and preferably, a flexible metal strip 44 is also secured to the exterior mask surface which can be easily bent to further assist the mask in forming to the general contour of a patient's face. The metal is preferably soft such as aluminium so that it can be easily bent and formed by hand once the shield is placed on the patient. Protruberances or tabs 47 are formed on each side of the shield for securing the metal strip 44 as shown in Figure 2. The upper peripheral edge surface 24 is also formed to provide a gently rounded or curved surface where it is compressed against the patient's face to form the proper seal. Although an outward curved surface at the upper shell end 26 is shown, i.e., the outer edge being directed away from the shell interior, an inwardly curved surface may be used at the upper shell end such as is used in some known oxygen masks in which the upper shell edge is curled inwardly. Either shape may be used, so long as sealing engagement is provided to prevent the oxygencontaining gas directed upwardly in the shell from passing to the patient's eyes, which could cause undesirable drying or other eye injury or discomfort.

On the other hand, the lower portion of the shell need not be so formed since there is no engagement of the peripheral lower portion edge with the patient's face.

Although inner edge 38 may lightly touch the patient's face in the lower part of the cheeks adjacent the mouth, the lower outwardly extending peripheral surface 33 does not make contact, and indeed, is designed to provide an opening as previously described. In any event, it is understood that there is no problem of any gas sealing engagement of the lower portion of the shell member, below the gas delivery tube, since it is intended and specifically provided that the lower shell portion be open as described. The face shield according to the invention provides delivered patient oxygen concentrations of between 22 and 65% at flow-rates between 1 and 10 liters per minute. Thus, accurate deliveries throughout the low and medium concentration ranges can be achieved.

Moreover, because of the open bottom feature, there is no problem with CO2 accumulation in the shell due to constant oxygen flow flushing exhaled gas into the atmosphere.

A further optional embodiment is an inwardly directing curl illustrated in Figure 5 which provides or forms a sort of pocket 45 to assist in increasing oxygen concentration within the shell. In this embodiment, the bottom edge 40 of the lower shell portion is curved inward and slightly upward toward the shell interior to form the pocket 45, which feature has been found to increase oxygen concentration within the shell without otherwise increasing the concentration or volume of oxygen delivered.

As previously noted, the face shield is preferably made of a soft, resilient, and flexible materials such as PVC (polyvinyl chloride) or other suitable and equivalent material. The gas delivery pipe is produced from a more rigid material such as rigid PVC or rigid polyethylene, polypropylene or the like. When these components are separately formed, they are assembled in a simple manner as previously described, utilizing the formed channel shown. Alternatively, it may be desirable to mold the device from a single mold in which the gas delivery pipe is integrally formed with the shell member. Accordingly, any method of preparing the shell member having the sealing engagement with the face along the upper portion, and the open lower portion and otherwise delivering oxygen through a plurality of orifices within the device, may be utilized.

Anv suitable means for securing the face shield to the patient's head such as an eleastic band 49 secured through openings 51 as shown in Figures 1 and 2, or any other equivalent means may be used. It will be understood, because of the advantages of the invention, that the placement of the device is not so critical since a gas tight seal around the patient's lower face area is not required. Moreover, because of the open bottom feature, patient comfort is maximized as is drainage from the patient's mouth area without danger of aspiration of liquids. These as well as other advantages and modifications within the purview of the invention will be evident to those skilled in the art.

WHAT WE CLAIM IS: 1. A face shield for delivering gas to a patient during respiratory therapy and adapted to be secured over the patient's nose and mouth comprising: a unitary shape-retaining shell member having an upper peripheral surface adapted for lying against the patient's cheeks and across the nose bridge and a lower edge which, when said device is secured on a patient, forms a space between the face of the patient and the shield and a gas delivery member extending along the shell interior and having at least one gas deliver orifice therealong.

2. A shield according to claim 1 wherein the lower part of said shell member is arched outwardly in relation to a patient's face.

3. A shield according to claim 1 or 2 wherein the upper peripheral surface is adapted to provide a substantially gas tight seal with the patient's nose bridge and cheeks to prevent gas from being directed to the eyes.

4. A shield according to any of the preceding claims wherein the shell member is flexible.

5. The shield of claim 1 wherein said lower edge is directed inwardly in relation to a patient.

6. The shield of claim 1 wherein the gas delivery member is an elongated pipe having a plurality of gas delivery orifices therealong and having means for connecting a gas supply tube.

7. The shield of claim 6 wherein said shell includes a channel for receiving the pipe.

8. The shield of claim 7 wherein said pipe is arched downwardly toward said lower edge and wherein said gas delivery orifices direct said gas upwardly.

9. The shield of claim 7 wherein said pipe is arched downwardly toward said lower edge and wherein a portion of said gas delivering orifices direct gas upwardly and a portion of said orifices direct gas downwardly toward said lower edge.

10. The shield of claim 1 wherein said gas delivery member extends across said shell between said upper and lower portions.

11. The shield of claim 10 wherein said gas delivery member includes a channel formed along the interior shell surface between the upper and lower portions, and

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. cheeks adjacent the mouth, the lower outwardly extending peripheral surface 33 does not make contact, and indeed, is designed to provide an opening as previously described. In any event, it is understood that there is no problem of any gas sealing engagement of the lower portion of the shell member, below the gas delivery tube, since it is intended and specifically provided that the lower shell portion be open as described. The face shield according to the invention provides delivered patient oxygen concentrations of between 22 and 65% at flow-rates between 1 and 10 liters per minute. Thus, accurate deliveries throughout the low and medium concentration ranges can be achieved. Moreover, because of the open bottom feature, there is no problem with CO2 accumulation in the shell due to constant oxygen flow flushing exhaled gas into the atmosphere. A further optional embodiment is an inwardly directing curl illustrated in Figure 5 which provides or forms a sort of pocket 45 to assist in increasing oxygen concentration within the shell. In this embodiment, the bottom edge 40 of the lower shell portion is curved inward and slightly upward toward the shell interior to form the pocket 45, which feature has been found to increase oxygen concentration within the shell without otherwise increasing the concentration or volume of oxygen delivered. As previously noted, the face shield is preferably made of a soft, resilient, and flexible materials such as PVC (polyvinyl chloride) or other suitable and equivalent material. The gas delivery pipe is produced from a more rigid material such as rigid PVC or rigid polyethylene, polypropylene or the like. When these components are separately formed, they are assembled in a simple manner as previously described, utilizing the formed channel shown. Alternatively, it may be desirable to mold the device from a single mold in which the gas delivery pipe is integrally formed with the shell member. Accordingly, any method of preparing the shell member having the sealing engagement with the face along the upper portion, and the open lower portion and otherwise delivering oxygen through a plurality of orifices within the device, may be utilized. Anv suitable means for securing the face shield to the patient's head such as an eleastic band 49 secured through openings 51 as shown in Figures 1 and 2, or any other equivalent means may be used. It will be understood, because of the advantages of the invention, that the placement of the device is not so critical since a gas tight seal around the patient's lower face area is not required. Moreover, because of the open bottom feature, patient comfort is maximized as is drainage from the patient's mouth area without danger of aspiration of liquids. These as well as other advantages and modifications within the purview of the invention will be evident to those skilled in the art. WHAT WE CLAIM IS:

1. A face shield for delivering gas to a patient during respiratory therapy and adapted to be secured over the patient's nose and mouth comprising: a unitary shape-retaining shell member having an upper peripheral surface adapted for lying against the patient's cheeks and across the nose bridge and a lower edge which, when said device is secured on a patient, forms a space between the face of the patient and the shield and a gas delivery member extending along the shell interior and having at least one gas deliver orifice therealong.

a gas delivery pipe secured in said channel.

12. The shield of claim 10 wherein said lower portion has a peripheral edge arched outwardly away from a patient on which the device is secured, to form an enlarged port communicating with the shell interior.

13. A face shield for delivering gas to a patient substantially as hereinbefore described with reference to the accompanying drawings.