General-purpose breath detector

Abstract

A universal breath detector for detecting respiratory gases can include multiple layers with visual indicators that rapidly and reversibly change color to detect respiratory gas parameters, such as carbon dioxide. The color change is visible from both sides of the detector. In some examples, the breath detector can be a biocompatible and conformable sticker for attachment to a person's face or an oxygen delivery device.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Application No. 63 / 040,372, filed June 17, 2020, which is incorporated herein by reference in its entirety. Incorporation by Reference

[0002] All publications and patent applications mentioned in this specification are herein incorporated by reference in their entirety to the same extent as if each individual publication or patent application was specifically and individually indicated to be incorporated by reference.

[0002]

[0003] Described herein are sensors useful for detecting respiration, particularly for detecting respiratory parameters, such as respiratory gases, from an individual and displaying a visual signal indicative of the individual's respiratory status based on the detected respiratory parameters. [Background technology]

[0003]

[0004] Oxygen is essential for life. Humans cannot store much oxygen in their bodies. Rhythmic breathing, called ventilation, to supply the body with oxygen is important for maintaining bodily functions. A person who stops breathing for just three minutes can suffer permanent brain damage and die within a few more minutes unless ventilation is restored. Inadequate breathing, such as shallow or irregular breathing, can lead to oxygen deprivation and problems such as headaches, confusion, shortness of breath, weakness, and impaired heart and brain function.

[0004]

[0005] The chest rises and falls during breathing, and one way to monitor breathing is by observing proper chest rise. However, chest rise can be subtle and difficult to observe when a person is covered with blankets, wearing bulky clothing, in poorly lit areas, or when breathing is shallow. Some hospitals monitor patients' respiratory status using monitoring devices specifically designed to monitor exhaled air. Commonly used monitoring devices measure the amount or concentration of carbon dioxide in exhaled air and display the data numerically or graphically. These devices may have a variable air sampling line, detector, display, battery, or other power source and may need to be attached to the device delivering oxygen to the patient. For example, monitoring devices are commonly used by anesthesiologists who attach the device to a tube placed in the patient's airway (intubated patients) and collect exhaled breath samples during surgery, or by medical personnel who collect exhaled breath samples from an oxygen face mask. These monitoring devices are available in limited environments and require training to use properly. These devices are susceptible to contamination by viruses and other biological agents. They may also be bulky, relatively expensive, difficult to decontaminate, or require warm-up time. Another monitoring device is a patch attached to the device that delivers oxygen to the patient. These patches can be bulky, have a short lifespan, and require the oxygen delivery device to adhere.

[0005]

[0006] Therefore, there is a need for improved devices for monitoring respiration to overcome these and other problems. Described herein are systems, devices, and methods for determining a person's respiratory status that can address these and other problems. Summary of the Invention

[0006]

[0007] One aspect of the present disclosure provides a universal breath detector that detects a respiratory gas and indicates a respiratory status based on the gas, the breath detector including: a first side and a second side; a cover layer; a breath sensor layer including a backing and a visual indicator on the backing, the visual indicator configured to reversibly change color and indicate the color change when a respiratory gas parameter changes, the color change being visible from both the first side and the second side; and the cover layer covering at least a portion of the backing. Some detectors include an adhesive ring on the second side that bonds the breath sensor layer to the cover layer, the adhesive ring including a central region configured to allow exhaled air to pass therethrough.

[0007]

[0008] In any of these detectors, the universal breath detector is a sticker. In any of these detectors, the universal breath detector can be configured to conform to the curved or variable surface contours of the oxygen delivery device or the user's face, flex, and move with the movements of the oxygen delivery device or the user's face.

[0008]

[0009] In any of these detectors, the universal breath detector includes a low-offgassing adhesive, a no-offgassing adhesive, a silicone adhesive, a low-VOC adhesive, and / or a low-VOC acrylic adhesive on the adhesive ring. In any of these detectors, the universal breath detector can further include a biocompatible adhesive on the cover and a release liner on top of the biocompatible adhesive.

[0009]

[0010] In any of these detectors, the backing of the universal respiration detector may comprise polyethersulfone, polysulfone, or polyphenylenesulfone.

[0010]

[0011] In any of these detectors, the general-purpose breath detector has a maximum thickness of less than 0.1 inches. In any of these detectors, the general-purpose breath detector has a longest dimension of less than about 1 inch.

[0011]

[0012] In either of these detectors, the universal breath detector is configured to reversibly change color in response to carbon dioxide.

[0012]

[0013] In both of these detectors, the universal respiration detector is biocompatible.

[0013]

[0014] In any of these detectors, the adhesive ring of the universal breath detector contains a transparent or translucent membrane in the center.

[0014]

[0015] In any of these detectors, the visual indicator is configured to reversibly change color when the respiratory gas parameter changes and to display the color change for a period lasting at least 10 minutes, at least 1 hour, at least 10 hours, at least 1 day, at least 3 days, at least 1 week, or at least 2 weeks.

[0015]

[0016] In any of these detectors, the detectors can be configured to be non-metallic, latex-free, and single-use disposable.

[0016]

[0017] The novel features of the invention are set forth with particularity in the following claims. A better understanding of the features and advantages of the present invention will be obtained by reference to the following detailed description that sets forth illustrative embodiments, in which the principles of the invention are utilized, and the accompanying drawings. [Brief explanation of the drawings]

[0017] [Figure 1]

[0018] Figure 1A illustrates an example of a universal breath detector applied to different parts of an individual's face to detect respiratory gases from the individual, Figure 1B illustrates an example of a universal breath detector applied to different parts of an individual's face to detect respiratory gases from the individual, and Figure 1C illustrates an example of a universal breath detector applied to different parts of an individual's face to detect respiratory gases from the individual.

[0019] FIG. 1D is a diagram illustrating the anatomy of the face. [Figure 2A]

[0020] FIG. 1 illustrates a universal breath detector for detecting respiratory gases on an individual's face using an oxygen cannula to receive a supply of oxygen. [Figure 2B]

[0021] Figure 2B shows a nasal cannula similar to that shown in Figure 2A, ready for use for a male with facial hair. A universal breath detector is glued to the exterior of the nasal cannula for detecting respiratory gases. [Figure 2C]

[0022] FIG. 1 illustrates a man with facial hair having a universal breath detector for detecting respiratory gases attached to his mustache. [Figure 3]

[0023] 3A illustrates a universal breath detector for detecting respiratory gases on the inner surface of an oxygen face mask. The universal breath detector's rapidly reversible visual signal, responsive to the presence or absence of respiratory gas, is readily visible to a healthcare provider or other individual viewing the face mask.

[0024] Figure 3B illustrates a universal breath detector for detecting respiratory gases on the exterior surface of an oxygen face mask similar to that shown in Figure 3A, but with the detector mounted on the mask in an opposite orientation relative to the detector shown in Figure 3 A. The universal breath detector's rapidly reversible visual signal, responsive to the presence or absence of respiratory gas, is readily visible to a healthcare provider or other individual viewing the face mask. [Figure 4]

[0025] 4A shows a universal breath detector for detecting respiratory gases on the interior surface of an infant oxygen tent. The universal breath detector's rapidly reversible visual signal, responsive to the presence or absence of respiratory gases, is visible to a healthcare provider or individual viewing the tent.

[0026] Figure 4B shows a universal breath detector for detecting respiratory gases attached to an infant's face. The infant is in an oxygen tent similar to that shown in Figure 4A, but the breath detector in Figure 4B is attached in an opposite orientation relative to the detector shown in Figure 4A. The universal breath detector's rapidly reversible visual signal, responsive to the presence or absence of respiratory gases, is easily visible to a healthcare provider viewing the infant's face. [Figure 5]

[0027] FIG. 5A shows a general-purpose breath detector 4 for detecting respiratory gases attached to the neck skin of a tracheotomy patient who has a stoma in the neck for breathing.

[0028] 5B shows a general-purpose breath detector 4 for detecting respiratory gases attached to a tracheostomy tube of a tracheotomy patient who has a stoma in the neck for breathing. The general-purpose breath detector 4 is placed near the opening where air exchange occurs.

[0029] FIG. 5C illustrates a universal breath detector 4 for detecting respiratory gas attached to the inside of a tracheostomy mask of a tracheostomy patient who has a stoma in the neck for breathing. The breath detector in FIG. 5C is similar to that shown in FIG. 5B, but is attached in an opposite orientation relative to the detector shown in FIG. 5B. The universal breath detector's rapidly reversible visual signal, responsive to the presence or absence of respiratory gas, is easily visible to a caregiver or healthcare provider. [Figure 6]

[0030] FIG. 6A is a different view of a general-purpose breath detector with a visual indicator visible from either side and an adhesive ring that serves multiple purposes. FIG. 6A is a top view of the general-purpose breath detector. For clarity, the top transparent cover 86 has been omitted from this view. FIG. 6B is a different view of a general-purpose breath detector with a visual indicator visible from either side and an adhesive ring that serves multiple purposes. FIG. 6B is a top view of a general-purpose breath detector that includes a transparent film 86 on top. The circle in the center indicates the area where the layers overlap. FIG. 6C is a different view of a general-purpose breath detector with a visual indicator visible from either side and an adhesive ring that serves multiple purposes. FIG. 6C is an exploded view of the detector, showing how the different diameters work together to create a detector that is versatile and easy to manufacture. [Figure 7]

[0031] FIG. 1 is an exploded view of a multi-layered general-purpose respiratory detector with an adhesive ring and a transparent backing. [Figure 8]

[0032] FIG. 8A is a diagram showing examples of general-purpose breath detectors of various shapes. FIG. 8B is a diagram showing examples of general-purpose breath detectors of various shapes. FIG. 8C is a diagram showing examples of general-purpose breath detectors of various shapes. FIG. 8D is a diagram showing examples of general-purpose breath detectors of various shapes. FIG. 8E is a diagram showing examples of general-purpose breath detectors of various shapes. FIG. 8F is a diagram showing examples of general-purpose breath detectors of various shapes. FIG. 8G is a diagram showing examples of general-purpose breath detectors of various shapes. FIG. 8H is a diagram showing examples of general-purpose breath detectors of various shapes. [Figure 9]

[0033] FIG. 1 illustrates an individual in a containment chamber with a universal breath detector applied near the nasal region and a medical professional observing the detector to determine the individual's respiratory status. [Figure 10]

[0034] FIG. 13 shows an exploded view of a multi-layered universal respiratory detector with tabbed indicators. DETAILED DESCRIPTION OF THE INVENTION

[0018]

[0035] Described herein are systems, devices, and methods useful for determining whether an individual is breathing and whether breathing is adequate. The systems, devices, and methods described herein may be useful for detecting respiratory characteristics, such as carbon dioxide gas levels in respiratory gases, and for indicating an individual's respiratory status based on the detection of the respiratory characteristics that indicate whether the individual is breathing adequately. The devices described herein provide a rapid-response visual detector that responds to changes in breathing and quickly displays a signal in response to the change (e.g., transition time of less than ½ second). The devices described herein can replace existing devices for detecting respiratory status and provide new solutions to currently unmet needs. The devices described herein are sometimes referred to as universal breath detectors because these detectors can be useful for detecting respiratory characteristics (e.g., carbon dioxide or another respiratory gas) under a wide range of health conditions, environmental conditions, and situations. The universal breath detectors described herein can be adapted to conform to and adhere to various types of surfaces and surface compositions, including various dry surfaces such as facial skin and oxygen delivery devices. The visual indicator of the universal breath detector is bilateral and can be viewed from either side. The universal breath detector is configured for easy application to a surface, optionally by removing a peel-and-stick adhesive and adhering the universal breath detector to the surface. The universal breath detectors described herein can be useful to individuals regardless of their characteristics (e.g., young, old, with facial hair, without facial hair, intubated, not intubated, in a hospital, in a public place, etc.) and regardless of whether the individual uses a respiratory aid (e.g., a face mask, an oxygen supply cannula, a CPAP mask, a tracheal collar, a hyperbaric chamber). The universal breath detectors described herein can be very unobtrusive, comfortable, and easy to wear and use. Therefore, a home medicine cabinet, first aid kit, car, combat hospital, ambulance, or clinic may need to stock only one type or only a few types of breath detectors. Furthermore, the universal breath detectors described herein can be easily applied by anyone. A family member, friend, or medical professional can apply the breath detector to an individual. An individual can apply it to themselves.

[0019]

[0036] 1A illustrates a general-purpose breath detector having a circular general-purpose breath detector 4 positioned below the nose or nostrils of an individual 10 and above the upper lip area of ​​the philtrum to detect respiratory characteristics such as carbon dioxide in exhaled breath. Carbon dioxide, a respiratory gas, may be used in this disclosure as an example respiratory parameter for ease of explanation, although any of the general-purpose breath detectors described herein may alternatively or additionally detect other respiratory characteristics or gases (e.g., pH, oxygen concentration of exhaled gases). Below the nostrils may be a suitable location for detecting respiratory gases emitted from the nostrils.

[0020]

[0037] As described in more detail below, the universal breath detector 4 has a breath indicator configured to reversibly respond, such as by changing color, when a respiratory gas parameter changes and to display a visual signal, such as a color change, based on the response. The breath indicator can be configured to rapidly reversibly respond, such as with each breath. The breath indicator can be configured to reversibly respond within ½ second. The universal breath detector can be configured to conform to and attach to a variety of surfaces. The universal breath detector is biocompatible and may include a biocompatible adhesive, allowing it to be attached to a person's face or skin and remain in place for hours or days with little or no irritation. The universal breath detector is detachable, allowing it to be removed from a person's face or skin with little or no damage to the face or skin. As can be seen in Figure 1D, the face, particularly the area around the nose and mouth, has a complex shape, with various depressions and extensions and abrupt changes between concavity and convexity. Figure 1D shows the philtrum below the nose, which extends and sinks into the philtrum ridge. Figure 1A shows a general-purpose breath detector 4 that conforms to irregular skin surface contours and conforms to convex and concave surfaces. When a person breathes through their nose, air exits through the nasal nostrils. The area below and near the nostrils may be suitable locations for a breath detector. However, some people exhale through their mouths or may be unable to fit a breath detector directly below or near their nose due to injury. Figure 1B shows a breath detector for detecting respiratory gases with a circular general-purpose breath detector 4 on the chin 24 of an individual 10. Figure 1D shows the anatomy of the chin in more detail. The chin is round or oval, and there is a crease at the chin called the mentolabilical sulcus. The general-purpose breath detector 4 is configured to conform to the round or oval shape, as well as the crease, to provide a smooth and comfortable fit. Figure 1C shows another variation of a breath detector for detecting respiratory gases, using an oval-shaped general-purpose breath detector 6 that is located below both nostrils and across the philtrum and philtrum ridge of an individual 10.In other variations, one or more general-purpose breath detectors can be applied to an individual, such as one under each nostril or one under the nose and one under the lip, which may be useful for detecting respiratory gases from individuals who occasionally exhale through their nose and occasionally through their mouth. Figures 1A-1C show an individual requiring breath monitoring who is not using a supplemental oxygen source. The breath detectors described herein may be particularly useful for assessing and / or monitoring the respiratory status of individuals with or suspected of having an infectious disease (e.g., avian influenza, COVID-19, chickenpox, Ebola, influenza, Middle East Respiratory Syndrome (MERS), Severe Acute Respiratory Syndrome (SARS)). The breath detectors described herein can be applied and assessed / monitored with minimal contact between caregivers and potentially infected individuals, particularly their breath. Figure 9 shows an individual in a containment chamber with a breath sensor 4 visible to medical personnel 138. The breath detectors described herein can be used without the need to sterilize or dispose of expensive equipment. The breath detectors described herein may be useful for rapidly assessing and / or monitoring individuals suspected of having or recovering from an illness, individuals with sleep apnea or other sleep-disordered breathing conditions, individuals with seizures (e.g., epilepsy), and individuals experiencing bronchospasm (e.g., asthma, COPD, allergic reactions). The breath detectors described herein may help recognize airway obstructions before an individual shows signs of a seizure. The breath detectors described herein may be useful for triage and quickly determining who needs supplemental oxygen or other assistance, such as when triaging a group of individuals involved in an accident or attack involving multiple potential victims. These and other breath detectors described herein may be useful for assessing and / or monitoring insufficient and excessive breathing. The breath detectors described herein may be useful for assessing and / or monitoring the treatment of individuals in respiratory distress or for transporting individuals in an ambulance or other medical transport vehicle. The breath detectors described herein may be portable and compact and do not require a power or battery power source.While Figures 1A-1C show an individual not using a supplemental oxygen source for breathing and a generic breath detector placed on the individual's face, the generic breath detector can also be used with individuals using a supplemental oxygen source, and the detector can be placed on the supplemental oxygen source itself. Figure 2A shows an individual 12 using an oxygen cannula 16 to deliver oxygen to the patient through prongs 18 placed in the individual's nostrils. Figure 2A also shows an individual 12 with a generic breath detector 4 placed under the individual's nose 32. As shown, the generic breath detector 4 is offset from the individual's midline, which may make the generic breath detector 4 more easily visible to medical professionals (the detector is not obstructed from view by the oxygen cannula 16). The offset position may prevent excessive friction from the oxygen cannula 16 from dislodging or irritating the generic breath detector 4. Figure 2B shows the oxygen cannula 16 ready for placement on an individual 20 with facial hair. Facial hair may make it more difficult to place the breath sensor 4 on the appropriate skin surface of the individual 20. Alternatively, the universal breath detector may be partially, mostly, or entirely adhered or wrapped around a portion of the oxygen cannula 16. FIG. 2B shows the universal breath detector 4 attached to the surface of the oxygen cannula 16. The universal breath detector 4 is easily visible to a healthcare provider or another individual who can easily see if the universal breath detector undergoes a visual change, such as a color change, indicating whether the person is breathing. FIG. 2C shows the universal breath detector 4 attached to the facial hair (moustache) of an individual 20. The sticker-type detectors described herein may be suitable for this and other indications.

[0021]

[0038] FIG. 3A shows an oxygen face mask 26 for placement over an individual's mouth and nose to provide oxygen to the individual. Oxygen enters the mask through an oxygen inlet 30, and positive pressure is used to move the oxygen to the mask's interior, where the individual can inhale it. When the individual exhales, exhaled gases leave the individual and enter the mask, then exit the mask through an exhalation port 28. Because gases exit the mask through the exhalation port 28, the area near the exhalation port 28 may be a suitable location for sampling and sensing exhaled gases from the individual. FIG. 3A shows a circular, universal breath detector 4 attached to the inside of the oxygen face mask 26 to sense exhaled gases from the individual. The oxygen face mask 26 is transparent or translucent, and the universal breath detector 4 is visible through the mask material. Notably, any color change in the universal breath detector 4 is visible from the outside of the mask. This orientation can be considered the first orientation relative to an observer, such as a healthcare provider, outside the mask. FIG. 3B shows the oxygen face mask 26 shown in FIG. 3A. However, in this face mask, the circular universal breath detector 4 is glued to the outside of the mask rather than the inside. Notably, the circular universal breath detector 4 shown in FIG. 3B is in a second or opposite orientation, in which the universal breath detector 4 is "flipped" relative to the circular universal breath detector 4 shown in FIG. 3A. As explained in more detail below, the visual signal associated with the breath detector is visible from both sides. Therefore, whether the universal breath detector is in the first orientation shown in FIG. 3A or the second "flipped" orientation shown in FIG. 3B, the visual signal associated with the breath indicator is visible to an observer. Configuring the universal breath detector to be mounted and visualized in either orientation simplifies the use of the breath indicator because the visual sensor can be detected regardless of how the detector is mounted. FIGS. 4A and 4B show another example of how the circular universal breath detector 4 can be used in either the first or second "flipped" orientation. FIGS. 4A and 4B show a baby 14 in an oxygen tent 36. Oxygen tent 36 is supplied with oxygen through oxygen inlet 38. Figure 4A shows universal breath detector 4 adhered or attached to the inside surface of oxygen tent 36 in a first orientation similar to the orientation shown in Figure 3A.Similar to the previously described FIGS. 1A-1C, FIG. 4B shows a general-purpose breath detector 4 adhered to the surface of a baby's face, specifically on the chin 24, in an opposite or second orientation compared to the general-purpose breath detector 4 shown in FIG. 4A. The oxygen tent detector, located closer to the face, can easily receive exhaled air as the body exhales under pressure. Because the visual detector is detectable from both sides, an observer (medical personnel or another individual) can easily assess the breathing status regardless of the detector's orientation and can switch from one detector to another.

[0022]

[0039] FIG. 5A shows a general-purpose breath detector 4 for detecting respiratory gases attached to the skin of the neck of a tracheostomy patient who has a stoma 44 in the neck for breathing. FIG. 5B shows a general-purpose breath detector 4 for detecting respiratory gases attached to a tracheostomy tube 46 of a tracheostomy patient who has a stoma 44 in the neck for breathing. The general-purpose breath detector 4 is positioned near the opening through which air exchange occurs. FIG. 5C shows a general-purpose breath detector 4 for detecting respiratory gases attached to the inside of a tracheostomy mask 48 of a tracheostomy patient who has a stoma in the neck for breathing. The breath detector in FIG. 5C is similar to the one shown in FIG. 5B but is attached in the opposite direction relative to the detector shown in FIG. 5B. The general-purpose breath detector's rapidly reversible visual signal, which responds to the presence or absence of respiratory gas, is easily visible to a caregiver or healthcare provider.

[0023]

[0040] A universal breath detector can include multiple layers, such as two, three, four, five, or more layers. The layers can be different from each other (unique) or the same (duplicated, with the duplicated layers in the same or opposite directions). Figures 6A-6C show different views of a universal breath detector 84 with multiple layers and a visual indicator visible from either side. The universal breath detector 84 has an adhesive ring that serves multiple purposes. Figure 6A shows a top view of the universal breath detector. For clarity, the top transparent cover 86 has been omitted from this view. The visual indicator at the bottom of the breath indicator 88 backing is visible from above through the transparent or translucent backing of the breath indicator 88. Figure 6B shows a top view of a universal breath detector with a transparent film 86 on top. The central circle indicates the area where the layers overlap. The thin ring 70 represents the overlap between the breath indicator 88 and the adhesive layer 90. FIG. 6C shows an exploded view of the universal breath detector 84 and how the different diameters of the different layers cooperate to create a versatile and easy-to-manufacture detector. The universal breath detector 84 includes a breath sensor 88 configured to respond to respiratory gases and display a visual signal based on the response, a first cover 86 on a first (or top) side 92 of the detector, and an adhesive layer 90 on a second (or bottom) side 94 of the detector opposite the first side 92. The breath sensor 88 is at least partially disposed between the first cover 86 and the adhesive layer 90. The breath sensor 88, and in particular the color of the breath sensor 88, is visible from both the first side 92 of the sensor and the second side 94 of the sensor. As described above (and with reference to FIGS. 1A-4B), the universal breath detector 84 can be mounted in either a first orientation or a second (“flipped”) orientation, and the color of the breath sensor 88 can be visualized and evaluated / monitored by an individual from either (or both) sides. Cover 86 can be transparent or translucent, allowing respiratory sensor 88 to be viewed from first side 92. Adhesive layer 90 includes an adhesive ring or "frame" and a central open area in the center of the ring or frame through which a visual indicator on respiratory sensor 88 can be viewed from second side 94. Adhesive layer 90 has adhesive on the top side (the side facing first side 92 in FIG. 6C ).In this example, adhesive layer 90 has an outer diameter that is larger than the outer diameter of the other layers of universal breath detector 84, such that the adhesive layer (e.g., the outermost ring of adhesive layer 90) can be used to attach universal breath detector 84 to a surface (on upper side 92), such as an individual's cheek or face, or the inside or outside of a mask or tent. Because of the different diameters, the adhesive of adhesive layer 90 bonds breath sensor 88 and cover 86 to itself, with excess material exceeding the outer diameter of cover 86, which is what bonds the detector to its final surface (cheek, mask, etc.).

[0024]

[0041] The breath detectors described herein, such as the breath sensor 88, include breath sensors with visual indicators, etc. The breath sensor can include a backing and a visual indicator disposed on the backing. In some variations, the breath sensor can include a visual indicator without a backing. The backing can be useful for supporting the visual indicator, particularly a chemical indicator. The backing can be a relatively flat layer and can have surface features, such as pores or openings. A visual indicator disposed on the backing can be disposed in the pores or openings of the backing and / or in a coating or layer of the backing. The backing can be on a first side of the breath sensor layer and the visual indicator on a second side of the layer. A transparent or translucent backing allows the visual indicator to be seen through the backing, and the visual indicator can be detected from either side of the backing. In some variations, the backing can be in the center of the breath sensor layer and have visual indicators on both sides of the backing (e.g., a first (top) side and a second (opposite) side). A backing with visual indicators on both sides can be transparent, translucent, or opaque. A universal breath detector can have a single breath sensor layer or two or more layers of breath sensors. Multiple breath sensor layers can be stacked in a breath detector, as a transparent or translucent backing allows the visual signal to be seen through multiple layers of transparent or translucent substrate. Breath detectors with multiple layers of visual indicators can provide stronger, brighter, or otherwise more easily detectable visual changes. In some embodiments, a breath device can include two backings (back to back), each with a visual indicator on one side. The backings can be stacked with the indicators facing away from each other so that the indicators are visible from both sides of the detector. A universal breath detector can include one layer or more (two, three, four, five, six, or more than six layers). In some breath sensor embodiments, a visual indicator is included within a transparent film on one or both sides.

[0025]

[0042] This detector or any detector described herein can include an indicator material, particularly a visual indicator (colorimetric) material, for detecting a respiratory characteristic or other chemical and, in response, generating and displaying a visual signal, such as a color signal. The indicator material can be configured to rapidly respond to changes and exhibit a reversible and detectable color change with each inhalation and exhalation. The indicator material can detect the presence, absence, and / or concentration or level of a respiratory characteristic, such as a respiratory gas. The visual indicator material can display various visual characteristics depending on the presence, absence, and / or concentration or level of a respiratory characteristic, such as a respiratory gas. The visual indicator can change between at least two different colors (e.g., yellow and blue, red and blue, green and red) as the concentration of the respiratory characteristic changes during breathing. The visual indicator can change color, amount of color, or hue (e.g., along the light spectrum), particularly in the visible light spectrum. The indicator material can visually indicate the presence, absence, and / or concentration or level of a respiratory characteristic in a rapidly reversible reaction. The presence, absence, and / or concentration or level of a respiratory characteristic can be assessed qualitatively or quantitatively. The presence or absence of respiratory characteristics, including respiratory gases, may refer to relative levels rather than absolute levels. For example, an indicator material can detect the presence of carbon dioxide in exhaled air sufficient for an individual to exhale (breathe or respire). However, low levels of carbon dioxide are typically present in unbreathed air. The low levels of carbon dioxide in unbreathed air are low enough that a detector can be configured to record or consider carbon dioxide as absent or undetectable (e.g., as an absence of exhaled carbon dioxide, since the carbon dioxide present in the air is not due to the individual's breathing / exhalation). Thus, in practice, the absence of carbon dioxide indicates a lack of breathing or respiration at a level sufficient to support the individual. Exhaled gas typically contains 4% to 5% carbon dioxide, while air or inhaled gas typically contains 0.03% to 0.04% carbon dioxide. Exhaled gas exhibits a 100-fold increase in the amount of carbon dioxide compared to inhaled gas (unbreathed air).A qualitative or quantitative assessment of the gas showing or suggesting less than about 4% to 5% carbon dioxide, such as 5-fold or more (e.g., 1.2% or 1.0%) lower, 10-fold or more lower, 50-fold or more lower, or 100-fold or more lower, or less than 1% carbon dioxide, less than 0.5% carbon dioxide, less than 0.1% carbon dioxide, or less than 0.05% carbon dioxide with an indicator, can be considered a sufficiently low level of carbon dioxide to indicate that a breath or exhaled breath is not being properly detected. Note that while exhaled breath generally contains more than 4% carbon dioxide, the breath detectors described herein may detect less than that and the breath can be considered acceptable. For example, a breath detector placed on the inside surface of an oxygen tent or on an individual's check may encounter exhaled breath mixed with room air, resulting in a lower, but still acceptable, amount of carbon dioxide, indicating acceptable breathing in that situation. Similarly, room air or other inhalable air may contain more than about 21% oxygen, while exhaled breath contains about 16% oxygen. The breath detector described herein for detecting oxygen can detect more than 16% oxygen. However, the individual may be breathing. Detection can be calibrated by taking into account differences in indicators or circulatory behavior, rather than by absolute signal strength or signal intensity.

[0026]

[0043] The respiratory indicator may be configured to change color in response to changes in respiratory characteristics, particularly to reversibly change color as the respiratory characteristics cycle with inspiration and expiration. Respiratory indicators for detecting carbon dioxide may include thymol blue and sodium carbonate with glycerol or propylene glycol. Alternative reactions include thymol blue with monoethanolamine or propylene glycol with metacrestol purple.

[0027]

[0044] In the broadest sense, a carbon dioxide (CO2) indicator can be any convenient indicator that can convert a change in CO2 concentration of a gas in contact with the indicator into a detectable change, such as a detectable visual change, such as a colorimetric change. CO2 indicators of interest include, but are not limited to, those described in U.S. Patent Nos. 4,728,499, 4,879,999, 4,994,117, 5,005,572, 5,156,159, 5,166,075, 5,179,002, 6,436,347, 6,584,974, and U.S. Patent Application Publication No. 2006 / 02168282, the disclosures of which regarding CO2 indicator compositions are incorporated herein by reference.

[0028]

[0045] Some variations include long-lasting CO indicators that exhibit dynamic, rapid-response, reversible CO indication with breath-by-breath sensitivity and are storage-stable. The colorimetric CO indicators of the embodiments disclosed herein change color (e.g., from purple to yellow) when exposed to changes in CO concentration found in exhaled breath. In certain embodiments, the CO indicator can change color, e.g., from purple to yellow, in 2.5 seconds or less, such as 2 seconds or less, including 0.75 seconds or less, in response to changes in CO concentration in gas contacting the indicator. The indicator is sensitive to changes in CO concentration of 3% or less, such as 2% or less, including 1% or less. At CO concentrations of 0.05% or less, such as 0.03% or less, the indicator is a first color, while at concentrations above these amounts, the indicator is a second color. For example, in certain embodiments, the indicator exhibits the following colors at the following CO concentrations: <0.03% purple; 0.5% mauve; 2% brownish-yellow; and 5% yellow. The color change can be any of a variety of different color changes, for example, purple to yellow, blue to yellow, red to yellow, orange to yellow, and the like.

[0029]

[0046] Some embodiments include a combination of various components in concentrations and ratios sufficient to provide a dynamic, fast-response, reversible CO2 indicator with breath-by-breath sensitivity, for example, as described above. In one embodiment, the components of the CO2 indicator include a pH-sensitive indicator dye and a phase transport enhancer.

[0030]

[0047] pH-sensitive indicator dyes of interest include, but are not limited to, bromothymol blue, phenolphthalein, thymol blue, phenol red, rosolic acid, m-nitrophenol, xylenol blue, curcumin, cresolphthalein, thymolphthalein, malachite green, N,N-dimethylaniline, and cresol dyes, such as bromocresol green, bromocresol purple, cresol red, m-cresol purple, etc. In certain embodiments, the pH-sensitive indicator dye is a cresol dye or a combination thereof, such as a combination of m-cresol purple and cresol red.

[0031]

[0048] In addition to the pH-sensitive indicator dye, another component present in the indicators described herein can be a phase transport enhancer. The phase transport enhancer, included as part of the dye solution applied to the substrate surface, not only enhances the dye's response to CO2 gas, but also alters the color and visibility of the indicator. Phase transport enhancers include, but are not limited to, quaternary ammonium salts, phosphonium salts, or pyridinium salts. Quaternary salts useful in the sensors described herein have the formula (I):

[0049]

[0032] [ka]

[0033]

[0050] where:

[0051] X=N or P;

[0052] R1, R2, R3 and R4 are selected from the group consisting of C1-C16, such as C1-C12 alkyl, triphenylmethyl, phenyl, naphthyl and benzyl, C1-C4 substituted alkyl, wherein the substituent is a C1-C4 alkyl group or a phenyl group; R1, R2, R3 and R4 may be the same or different, e.g., have the same or different number of carbon atoms; and Y- is an anion selected from the group consisting of hydroxide, fluoride, chloride, bromide, iodide, carbonate, and tetrafluoroborate.

[0034]

[0053] Phase transport enhancers useful in some embodiments include, but are not limited to, tetrabutylammonium hydroxide, tetrabutylammonium chloride, tetraethylammonium bromide, tetraethylammonium p-toluenesulfonate, phenyltrimethylammonium chloride, benzyltrimethylammonium bromide, tetra-n-propylammonium bromide, benzyltriethylammonium tetrafluoroborate, n-dodecyltrimethylammonium bromide, tetraphenylphosphonium chloride, n-hexadecylpyridinium bromide, and (triphenylmethyl)triphenylphosphonium chloride.

[0035]

[0054] Some embodiments can be produced by combining various components of the indicator composition to form a precursor indicator reagent fluid, and then contacting the fluid with a suitable solid support in a manner sufficient to produce the desired indicator composition. In certain embodiments, the precursor fluid is an aqueous solution, such as a basic aqueous solution, containing the pH-sensitive dye and phase transport component described above. The basic solution, in certain embodiments, has a pH in the range of 10 to 12.5. The composition may include one or a combination of pH-sensitive indicator dyes. In certain embodiments, the composition includes more than one pH-sensitive indicator dye, such as two to five different dyes, e.g., two to three different dyes, or two to four different dyes, including two different dyes. In certain embodiments, the dyes are cresol dyes, such as two different cresol dyes. When the composition includes two different pH-sensitive indicator dyes, the pH-sensitive indicator dyes can be present in a concentration ranging from 0.0001 to 0.01 molar, including about 0.002 molar to 0.003 molar. In certain embodiments, the dyes are m-cresol purple and cresol red. M-cresol purple can be present in the reagent fluid at a concentration ranging from 0.001 molar to 0.01 molar, including about 0.002 molar to 0.003 molar. Cresol red sodium salt can be present in the reagent fluid at a concentration ranging from 0.0001 molar to 0.001 molar, including about 0.002 molar to 0.003 molar. The concentration of the phase transport enhancer can vary. In certain embodiments, the amount of phase transport enhancer present in the reagent fluid ranges from 0.001 molar to 0.02 molar, such as 0.005 molar to 0.01 molar.

[0036]

[0055] Following preparation of the precursor fluid, the method can include contacting the fluid with a solid support and then removing excess fluid from the solid support to produce the indicator. Any convenient solid support can be used. In certain embodiments, the solid support is a flexible solid support (e.g., a cellulose material), such as paper. In certain embodiments, the solid support can be filter paper having a porosity ranging from 1 μm to about 60 μm, such as 20 μm to about 30 μm. The solid support can be a material sized to fit on the skin and / or inside an oxygen delivery device, as described herein. The support of the CO2 indicator can be shaped into any desired configuration, including, but not limited to, a circular or spiral strip, a sphere or portion of a sphere, a propeller, an accordion shape, etc. As described in the above embodiments, the support of the indicator can further include a pattern and / or have perforations.

[0037]

[0056] The indicators described above can be used in any of several different breath detectors. In certain embodiments, the indicators are used with breath detectors that do not include a sterilization barrier, as the indicators in such embodiments can withstand sterilization processes such as EtO.

[0038]

[0057] Returning to FIGS. 6A-6C, the adhesive layer 90 can be in the form of a ring or frame surrounding an open center portion. The open center portion allows exhaled air to contact the breath sensor 88 during use of the detector. The breath sensor 88 is visible through the center or "picture" portion of the ring or frame, such as to an individual assessing and / or monitoring the individual's respiratory status. The adhesive layer 90 can include a substrate having one or more adhesive compounds on the top side of the adhesive layer (e.g., the side facing the breath sensor 88 and the second side 94 of the sensor). The adhesive layer 90 can adhere to the outer portion of the breath sensor 88 and the bottom of the cover 86, holding the adhesive layer 90, the breath sensor 88, and the cover 86 together. The adhesive in the adhesive layer 90 that contacts the breath sensor 88 can be an adhesive that does not or only minimally interferes with the performance of the visual indicator. Examples of adhesives that can be used for the adhesive layer 90 include no-off-gassing or low-off-gassing adhesives, such as silicone adhesives and low-volatile organic compound (low-VOC) adhesives, such as low-VOC acrylics. In some variations, the adhesive layer 90 can additionally or alternatively have an adhesive surface facing the first side 92 of the sensor for attaching the breath indicator to the surface of the first side 92 of the sensor. The adhesive portion on the adhesive layer 90 can cover part or all of the top side of the adhesive layer 90. In some variations, the adhesive layer 90 need not cover the entire top side of the adhesive layer 90. The adhesive layer 90 can take other shapes, such as discontinuous adhesive (e.g., an array of small circles or squares of adhesive), or a two-dimensional spiral shape with adhesive spirals and open (non-adhesive) areas, or another shape. The breath sensor 88 can be seen through the discontinuous or open areas of adhesive. In some variations, the adhesive layer 90 includes an air-permeable or breathable membrane over part or all of its central portion. The breathable membrane can allow exhaled air from the individual to pass through and contact the breath sensor 88 while protecting the otherwise exposed (bottom) surface of the breath sensor 88. In some variations, an adhesive layer, such as the adhesive layer 90, can cover substantially the entire second surface of the sensor.A transparent (or translucent) adhesive may be suitable for covering the entire first side of the sensor because the signal (visual signal) from the respiratory indicator can be visualized through the transparent or translucent adhesive surface. In some variations, the adhesive may be opaque. While FIGS. 6A-6C show the adhesive layer 90 adjacent to the respiratory sensor 88 in the respiratory detector 84, in some variations, the adhesive may be provided separately from the respiratory indicator and attached to the respiratory detector during adhesive application of the respiratory detector to an individual. For example, the adhesive may be configured (and packaged) as a separate layer or gel (with a backing) that can be applied / attached to the remaining portions of the respiratory sensor 84 (the cover 86 and the respiratory sensor 88). In some variations, the detector may have adhesive on an adhesive layer, such as adhesive layer 90 in FIGS. 6A-6C, to attach the respiratory sensor 88 to the cover 86. In some variations, the adhesive layer 90 may attach the detector to an individual. In some variations, the detector may have adhesive, such as on the top of the cover 86, to attach the detector to an individual, in addition to or instead of the adhesive on the adhesive layer 90. A breath detector placed and adhered to facial skin or an oxygen delivery device may need to be removable, as it may remain on the skin or delivery device for a period of time (minutes, hours, days, or weeks) and then be removed. In some cases, the breath detector can be removed and replaced one or more times with a fresh / new additional breath detector placed on the facial skin or oxygen delivery. These additional breath detectors may also remain for a period of time (minutes, hours, days, or weeks). Ease of application and replacement of the breath detector may be important. Other detector characteristics that may be of interest for the breath detectors described herein include stability, ease of use, conformability, flexibility, adhesive ability, comfort, skin irritation, and ease of removal. In some embodiments, the visual indicator is configured to reversibly change color when a respiratory gas parameter changes and display a color change that lasts for at least 10 minutes, at least 1 hour, at least 10 hours, at least 1 day, at least 3 days, at least 1 week, or at least 2 weeks, or for a period of time between these amounts.The breath detector may be configured for conformability and flexibility to conform to uneven facial skin or irregularly shaped oxygen delivery devices, such as oxygen cannulas, and flexibility to stay in place and be comfortable to wear after placement. As noted above, it may be desirable to place the breath detector near where breath is exhaled, such as on the facial skin between the nose and mouth, in an irregular or flat area that may have either or both convex and concave surfaces. A detector that is flexible enough to accommodate attachment and remain flexible as a person talks, laughs, or otherwise moves their face may be desirable. Adhering anything to skin, especially facial skin, can be very difficult. Facial skin is delicate and sensitive, prone to damage, irritation, skin rashes, and acne, and the adhesive on the breath indicator (and other parts of the breath indicator) may be hypoallergenic and non-irritating for hours or days. The optimal adhesive for adhering the breath indicator to the oxygen delivery device may not be the optimal adhesive for adhering the breath indicator to an individual's facial skin, and vice versa. Facial skin has a low surface energy, making it difficult for adhesives to adhere even under the best of circumstances. Different individuals have different skin conditions that affect the adhesive's ability to adhere the breath indicator to their facial skin, and a universal breath detector can be configured to provide optimal adhesion in many environments. For example, individual differences in oiliness, dryness, sweating, and facial hair. The presence of face cream, ointment, or sunscreen on the facial skin can affect adhesion to the facial skin and the breath detector's adhesion. Adhering something to facial skin is very difficult, and even healthy skin can be painful and damaging to remove.

[0039]

[0058] As noted above, other adhesive properties that may be of interest for the breath detectors described herein are ease and comfort of removal. Concerns regarding skin trauma during adhesive removal may include concerns about skin tearing and peeling. The facial skin of young patients, such as babies, and elderly patients may be particularly sensitive to skin trauma. As skin ages, its dermal thickness decreases, thinning the skin and making it more susceptible to damage. Aging skin predisposes individuals to skin tears, including painful and unsightly peeling of the epidermal layer from the underlying dermal layer. These factors make it more difficult to atraumatically remove the breath detector adhesive. When selecting an adhesive, considerations may be given to ease of application of the breath detector, comfort during removal of the breath detector, and ensuring that the breath detector elements remain in place during use. For example, if the adhesive strength is too low, the breath sensor may not stay in place reliably. If the adhesive strength is too high, removal of the breath sensor may be difficult or may cause damage to the facial skin or oxygen delivery device. Adhesives for adhering and gently removing a respiratory device from skin or an oxygen delivery device can include adhesives and detectors that peel cleanly from the skin or device, leaving the skin area intact and no or little residue during removal. Gentle removal from the skin can also involve minimal or no pain during removal. The adhesive can be configured to be non-traumatic during application and removal. The adhesive performance of a respiratory sensor can balance various properties. Adhesive performance can be partially characterized by adhesive tack, peel, and / or shear. Tack is a measure of how quickly a bond forms between two surfaces, such as between an adhesive and a surface (e.g., skin or an oxygen delivery device), and can be used to refer to pressure-sensitive adhesives. In some embodiments, the adhesive is configured to be tacky or non-tacky at room temperature. To assess tack, two surfaces are briefly brought together with light pressure and then pulled apart. The greater the force required to separate them, the more adhesive the adhesion. Lower tack allows the adhesive to be displaced. Another characteristic of an adhesive is peelability.Peel is a measure of the force required to break the bond between the adhesive and the surface to which it is applied (e.g., skin or an oxygen delivery device). Peel tests can be performed to assess peel. In a peel test, adhesive tape is applied to a surface, allowed to sit, and then removed. The peel angle or direction, applied pressure, and length of time the surface remains bonded can be defined, such as in the ASTM D330D Standard Test Method for Measuring Peel Adhesion Strength of Pressure-Sensitive Tapes. In some examples, the adhesive can be left on the surface for at least 1 hour, at least 2 hours, at least 3 hours, at least 5 hours, at least 10 hours, at least 24 hours, at least 48 hours, or at least 60 hours, or for less than 60 hours, less than 48 hours, less than 24 hours, less than 10 hours, less than 5 hours, less than 4 hours, less than 3 hours, less than 2 hours, less than 1 hour, or any time in between (e.g., 10 hours or more but less than 48 hours). Another adhesive property is shear. Shear refers to the sliding of one surface over another. In a shear test, the sample is mounted vertically and a weight is attached. The time it takes for the sample to slide off the substrate indicates the durability of the bond. The adhesive may have sufficient tack to adhere to the device and / or skin, as well as good shear and peel properties to remain on and be easily removed from the device and / or skin. Adhesives for breath detectors may be or include acrylic, hydrocolloid, hydrogel, rubber-based adhesives, or polyurethane-based adhesives. Examples of adhesive polymers for adhesives include polysiloxane or silicone (DowCorning® BIO-PSA), polyisobutene (Oppanol®), silane-isoprene-styrene copolymer (JSR-SIS), or acrylic polymer (Duro-Tak). The adhesive substrate may be a sheet or film, such as a sheet or film of foam, polymer, plastic, or polyester resin (Mylar). The substrate may be transparent, translucent, or opaque.In some examples, the diameter (outer diameter) or other longest dimension (e.g., the length or diagonal of a non-circular layer) of the adhesive layer can be about 1 inch, or less than 2 inches, or less than 1.5 inches, or less than 1 inch, or less than 0.5 inches, or less than 0.25 inches, or at least 0.5 inches, at least 1.0 inches, at least 1.5 inches, or at least 2.0 inches, or any amount therebetween (e.g., at least 0.5 inches but less than 1 inch, at least 0.5 inches but less than 1.5 inches).

[0040]

[0059] In some variations, the first side of the sensor may have a cover over at least the central ("picture") portion of the ring or frame of adhesive layer 90 instead of, or in addition to, the first cover. As noted above, the first side of the universal breath detector may have a cover over the central or "picture" portion of the ring or frame of adhesive layer 90 instead of, or in addition to, the first cover. In some embodiments, the cover is a film. In some variations, the breath sensor does not have a cover.

[0041]

[0060] FIG. 7 shows an exploded view of another breath detector, a universal breath detector 116. Similar to that described above for the universal breath detector 84 of FIGS. 6A-6C, the universal breath detector 116 shown in FIG. 7 includes a breath sensor 88 configured to respond to a breath parameter (e.g., a gas such as CO) and display a visual signal based on the response. The universal breath detector 116 includes an adhesive layer 90 and a first cover 86 on the second side 114 of the sensor, and the breath sensor 116 includes a release liner 96 on the first side 112 of the detector. As noted above, the breath sensor 88 and any other breath sensors described herein may include a backing and a visual indicator on the backing. The backing may be a porous material and may be configured to allow the visual indicator to penetrate or otherwise retain the pores during manufacturing, storage, and use of the detector. The pores in the backing may be irregular (e.g., in a polymer) or regular (e.g., laser-drilled). The pores may have an average pore size of about 0.65 μm, or about 0.45 μm to about 0.8 μm, or about 0.1 μm to about 2 μm, or about 0.03 μm to about 5.0 μm, or any size therebetween. In some variations, the average pore size may be greater than 5 μm, as indicated elsewhere herein. The visual indicator can be configured to display / change with each breath, such as within 3 seconds, 2 seconds, 1 second, or 0.5 seconds. The backing may be a polymer, such as polyethersulfone, polysulfone, or polyphenylenesulfone. The backing may be transparent or translucent (e.g., the visual indicator can be evaluated from both sides of the universal breath detector 94) so ​​that the visual indicator can be visualized through the backing, or may be opaque. The visual indicator, as indicated elsewhere herein, may be adhered or attached to the backing, such as using pad printing. A visual indicator can be printed on the bottom surface (e.g., facing second side 114) of respiratory sensor 88 by pad printing. In some examples, a visual indicator printed on the second side of a respiratory sensor, such as respiratory sensor 88, contacts an adhesive, such as on adhesive layer 90, when respiratory sensor 88 and adhesive layer 90 are bonded together.In some examples, the visual indicator is printed so that it does not come into contact with the adhesive when the respiratory sensor 88 and adhesive layer 90 are bonded together. Contact of the visual indicator with the adhesive can have detrimental effects on the visual indicator, such as reducing its shelf life or effectiveness. Preventing or minimizing contact between the visual indicator and the adhesive can extend the life of the visual indicator. A solution containing the visual indicator, a plasticizer, and isopropyl alcohol can be placed on a backing (e.g., a polyethersulfone film), the visual indicator cured on the substrate, and the isopropyl alcohol can be flashed off by heating at 80°C for 10 minutes or 90°C for 5 minutes. The respiratory sensor 88 also includes a first cover 86. The first cover 86 is laminated on the top side of the respiratory sensor 88, and the top side of the respiratory sensor 88 can be sealed by the first cover 86 to protect the visual indicator 88 and increase the durability of the sensor. The first cover 86 can protect the visual indicator from moisture and prevent oxidation. In some examples, the visual indicator is configured and protected to provide a visual indication for at least 1 day, at least 2 days, at least 3 days, or at least 4 days of use. In some examples, the universal breath detectors described herein, such as universal breath detector 84, are protected around their edges by a coating, film, or bead.

[0042]

[0061] FIG. 7 also shows that the breath sensor 88 includes a release liner 96. A release liner, such as release liner 96, can be a thin, removable layer that protects the universal breath detector 116. In particular, the release liner 96 can protect the adhesive layer 90, maintain the integrity of the adhesive on the release liner 96 prior to detector installation, prevent contact with air, dirt, or other objects, and prevent premature adhesion. In some variations, the breath detector can have a second release liner for a second adhesive layer or second adhesive surface. A release liner, such as release liner 96, is removed prior to installation and use of the universal breath detector 94. Steps in a method of using the release liner can include protecting the universal breath detector with the release liner and removing or separating the release liner from the remainder of the universal breath detector. The release liner may be larger or longer (in diameter, width, and / or length) than another portion of the universal breath detector, smaller or shorter (in diameter, width, and / or length) than another portion of the universal breath detector, or the same size as another portion of the universal breath detector. In some variations, the universal breath detector may have a release liner on the first side of the sensor instead of or in addition to a release liner on the second side 114 of the sensor, and the breath detector may have zero, one, two, or more release liners. The release liner may be a substrate coated on one or both sides with a release agent configured to separate the release liner from the adhesive (and / or other materials) of the breath sensor. The release liner may be paper, plastic, fluoropolymer, polyethylene film, or a silicone-coated layer. The release liner may be smooth or textured with release properties that allow for adhesion of the adhesive while allowing clean separation from the adhesive during application of the breath sensor to a surface. The release liner may include one or more cutting features or extensions, such as a central notch or hole, as shown in FIG. 7, or partial line cuts or tab extensions that may aid in application and / or removal of the respiratory sensor.In some examples, the diameter (inner diameter) or other dimension of the internal opening of the release layer (e.g., the diagonal of a rectangular layer) can be less than 2 inches, less than 1.5 inches, less than 1 inch, or less than 0.5 inches, or at least 0.5 inches, at least 1.0 inches, at least 1.5 inches, or at least 2.0 inches, or any amount therebetween (e.g., 0.5 inches or more and less than 1 inch, 0.5 inches or more and less than 1.5 inches), such as 0.5 inches or more and less than 1.0 inches, 0.5 inches or more and less than 1.5 inches, etc. The release liner can be sized to extend beyond the perimeter of the remainder of the respiration sensor, for example, by at least 0.25 inches, at least 0.5 inches, or at least 1 inch. Another layer can also, or instead, have a tab or ring extension. The cutting feature or extension can aid in detector placement or separation of the release liner from the adhesive or another portion of the universal respiration detector. Cutting features or extensions, such as for the adhesive layer and the detection chemical, can help minimize contact between the adhesive and the detection chemical. Such minimization can be advantageous, for example, if the adhesive has a detrimental effect on the stability of the detection chemical. The tab can be rectangular, V-shaped (narrow near the body), inverted V-shaped (wide near the body), rounded, or another shape. The tab can be flat and have the same or similar thickness as the layer to which it is connected. The tab can be flexible or inflexible. As shown above, the respiration detector can be round or oval. In these and other embodiments, the universal breath detector does not have sharp edges or corners. A circle may be the most efficient and stable shape because sensor degradation may begin at the outer edge and move inward. Other shapes are also contemplated for the breath detector. Figure 8A shows a rectangular universal breath detector 120. Figure 8B shows a rectangular universal breath detector 122 with rounded squares.FIG. 8C shows a triangular rectangular generic breath detector 124. FIG. 8D shows a cut rectangular generic breath detector 126. FIG. 8E shows a graphic representation of a decorated rectangular generic breath detector 128. FIG. 8F shows a crescent-shaped rectangular generic breath detector 130. FIG. 8G shows a split rectangular generic breath detector 132 having two sections 131. Part 131 may include adhesive, an indicator, or any breath detector material as described herein. FIG. 8H shows a star-shaped section 134. FIG. 10 shows an exploded view of a generic breath detector 146 similar to the above, but with a breath sensor 148 with four tabs 150. When an adhesive layer 152 is placed over the breath sensor 148, the amount of contact between the adhesive layer 152 and the breath sensor 148 can be minimized. For example, contact can be limited to the area between the tabs and the adhesive layer and / or a thin ring 154 around the circumference of the breath sensor 148. Respiratory sensor 148 may have three, four, or five tabs (or another number of tabs, such as one tab, two tabs, more than five tabs, or no tabs). The tabs (or the extent of respiratory sensor 148 if there are no tabs) may extend such that the outermost dimension of respiratory sensor 148 is the same outermost dimension (e.g., circumference) as some or all of the other layers of the respiratory sensor. Having the same outermost dimension for some or all of the layers may aid in manufacturing. A series of layers of material may be laminated together, and a respiratory sensor, such as respiratory sensor 146, may be punched out of the layers. Multiple detectors may be manufactured together in sheet or web / roll form. In another embodiment, the various layers of a respiratory sensor, such as respiratory sensor 146, may be molded (punched or cut) separately and then aligned after molding (punched or cut) to form an assembled respiratory sensor, either individually or in groups. Multiple detectors may be assembled simultaneously. The tabs can extend beyond the circumference of the body (e.g., 0.1 inches or less, 0.2 inches or less, 0.3 inches or less, 0.4 inches or less, or 0.4 inches or more outward from the ring 154 as shown by the arrows in FIG. 10 ).The tabs can be 0.2 inches (0.508 cm) or less in width, 0.1 inches (0.254 cm) or less in width, as shown by the double arrows in FIG. 10 which are 0.3 inches (0.762 cm) or less, 0.4 inches (1.016 cm) or less in width, or 0.4 inches (1.016 cm) or more in width. These extension and width dimensions can also apply to tabs of other shapes, such as the maximum, minimum, or average size of a V-shaped tab.

[0043]

[0062] Respiratory sensors such as the universal breath detectors 4, 6, 116, 120, 122, 124, 126, 128, 130, 132, and 134 can be configured as stickers (e.g., flexible, pliable, and thin, and capable of conforming to a surface and adhering to the surface with contact or minimal conforming pressure), and can be configured as removable stickers. Such sensors can be approximately 0.01 inches thick, such as between 0.005 inches and 0.05 inches, or between 0.001 inches and 0.1 inches. Each layer can be thin and flexible. The release liner 156 of FIG. 10 can be about 0.002 inches thick, such as between 0.0005 inches and 0.008 inches, or between 0.0002 inches and 0.02 inches, or between 0.001 inches and 0.1 inches. The cover 158 of FIG. 10 can be about 0.002 inches thick, such as between 0.0005 inches and 0.008 inches, or between 0.0002 inches and 0.02 inches, or between 0.001 inches and 0.1 inches. The cover 158 of FIG. 10 can be about 0.002 inches thick, such as between 0.0005 inches and 0.008 inches, or between 0.0002 inches and 0.02 inches, or between 0.001 inches and 0.1 inches. The breath indicator 148, which can include a backing with a visual indicator, can be about 0.004 inches thick, such as between 0.0004 inches and 0.04 inches, or between 0.0002 inches and 0.02 inches.In some variations, the breath sensor can have a rigid housing. The universal breath detectors described herein can be compatible with many types of oxygen delivery systems (e.g., face masks, nasal cannulas, continuous positive airway pressure (CPAP) machines, tracheostomy collars, oxygen tents). The universal breath detectors may be single-use, disposable, latex-free, non-metallic, magnetic resonance imaging (MRI) safe, and / or computed tomography (CT) safe. The universal breath detectors described herein may have sufficient visibility to be visible from at least 5 feet away, or at least 10 feet away. Once manufactured, the universal breath detectors described herein can be packaged in an airtight packet (e.g., Mylar). The entire packet may be small (e.g., less than 1.5 inches or 1 inch on each side and less than 0.1 inches or 0.05 inches thick). Some embodiments of the breath detector include a backing, an adhesive layer, a visual indicator, and an opaque surrounding layer. The opaque surrounding layer may include printed graphics, such as instructions or decoration.

[0044]

[0063] Working Example: [Example]

[0045]

[0064] The universal respiration detectors fabricated as described herein underwent accelerated stability testing to rapidly and accurately measure and estimate the stability of the universal respiration detectors. The universal respiration detectors were exposed to extreme conditions that enhance the rate of chemical and / or physical degradation that occurs under normal storage conditions. As shown in Figure 10, a universal respiration detector was fabricated and comprised a (top) release liner layer, a clear polyester layer with adhesive on top, a visual indicator on top of a polyethersulfone backing, and a (bottom) polyester with a low-offgassing acrylic adhesive on top and a notch in the center. The sensor was sealed in a Mylar foil package, heat-sealed, and artificially aged in a 55°C oven. After 18 days at 55°C (equivalent to 6 months in real time), the sensor showed no signs of degradation. [Example]

[0046]

[0065] The universal respiration detectors fabricated as described herein underwent accelerated stability testing to rapidly and accurately measure and estimate the stability of the universal respiration detectors. The universal respiration detectors were exposed to extreme conditions that enhance the rate of chemical and / or physical degradation that occurs under normal storage conditions. As shown in Figure 10, a universal respiration detector was fabricated and comprised a (top) release liner layer, a clear polyester layer with adhesive on top, a breath indicator layer on top of a polyethersulfone backing, and a (bottom) polyester with a silicone adhesive on top and a notch in the center. The sensor was sealed in a Mylar foil package, heat-sealed, and artificially aged in a 55°C oven. After 36 days (equivalent to 12 months in real time) at 55°C, the sensor showed no signs of degradation. [Example]

[0047]

[0066] The universal respiration detectors fabricated as described herein underwent accelerated stability testing to rapidly and accurately measure and estimate the stability of the universal respiration detectors during use. The universal respiration detectors were exposed to extreme conditions that enhance the rate of chemical and / or physical degradation that occurs under normal storage conditions. As shown in Figure 10, universal respiration detectors were fabricated and included a (top) release liner layer, a clear polyester layer with adhesive on top, a visual indicator layer on top of a polyethersulfone backing, and a (bottom) polyester with adhesive on top and a notch in the center. The sensors were not sealed in a package. The sensors were left open to the atmosphere (air). The sensors were artificially aged in an oven at 55°C. After 10 days at 55°C (equivalent to 3 months in real time), the samples showed a 50% decrease in efficiency. 50% of the chemical indicator remained permanently yellow, and 50% still changed from blue to yellow and then reversed. The degradation pattern was typically circular / oval, with degradation moving inward from the outer edge (e.g., degradation was observed closer to the interface between the respiration sensor layer (chemicals) and the adhesive, suggesting that the adhesive may have a negative effect on the stability of the respiration indicator (chemicals)). [Example]

[0048]

[0067] A polyethersulfone membrane was layered with a solution of a visual indicator, plasticizer, and isopropyl alcohol. The membrane was heated from 80°C to 180°C and visually evaluated. The color of membranes heated at 80°C for 10 minutes or at 90°C for 5 minutes was acceptable. The color of membranes heated at 180°C for 5 minutes was unacceptable.

[0049]

[0068] When a feature or element is referred to herein as being "on" another feature or element, it can be directly on top of the other feature or element, or intervening features and / or elements may also be present. In contrast, when a feature or element is referred to as being "directly on" another feature or element, there are no intervening features or elements present. When a feature or element is referred to as being "connected," "attached," or "coupled" to another feature or element, it will be understood that it can be directly connected, attached, or coupled to the other feature or element, or that intervening features or elements may be present. In contrast, when a feature or element is referred to as being "directly connected," "directly attached," or "directly coupled" to another feature or element, there are no intervening features or elements present. Although described or illustrated with respect to one embodiment, the features and elements so described or illustrated may be applicable to other embodiments. Those skilled in the art will also understand that a reference to a structure or feature being located "adjacent" to another feature may have portions that overlap or underlie the adjacent feature.

[0050]

[0069] The terms used herein are for the purpose of describing particular embodiments only and are not intended to be limiting of the invention. For example, as used herein, the singular forms "a," "an," and "the" are intended to include the plural forms unless the context clearly dictates otherwise. It will be further understood that the terms "comprises" and / or "comprising," as used herein, specify the presence of stated features, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components, and / or groups thereof. The term "and / or," as used herein, includes any and all combinations of one or more of the associated listed items and may be abbreviated as " / ."

[0051]

[0070] Spatially relative terms such as "under," "below," "lower," "over," and "upper" may be used herein to describe the relationship of one element or feature to another, as shown in the figures, for ease of description. It should be understood that spatially relative terms are intended to encompass various orientations of the device during use or operation in addition to the orientation shown in the figures. For example, if a device in the figures is inverted, an element described as "under" or "beneath" another element or feature would then be oriented "over" the other element or feature. Thus, the exemplary term "under" can encompass both an orientation of above and below. The device may be oriented otherwise (rotated 90 degrees or at other orientations), and the spatially relative descriptors used herein will be interpreted accordingly. Similarly, terms such as "upward," "downward," "vertical," "horizontal," and the like are used herein for descriptive purposes only, unless otherwise indicated.

[0052]

[0071] The terms "first" and "second" may be used herein to describe various features / elements (including steps), but these features / elements should not be limited by these terms unless the context dictates otherwise. These terms may be used to distinguish one feature / element from another. Thus, a first feature / element discussed below could be referred to as a second feature / element, and similarly, a second feature / element discussed below could be referred to as a first feature / element, without departing from the teachings of the present invention.

[0053]

[0072] Throughout this specification and the claims that follow, unless the context requires otherwise, the word "comprises" and variations such as "comprises" and "comprising" refer to the ability of various components to be used jointly in methods and articles (e.g., compositions and devices and apparatuses that include methods). For example, the term "comprising" should be understood to mean the inclusion of any stated element or step, but not the exclusion of any other elements or steps.

[0054]

[0073] Generally, any of the apparatus and methods described herein should be understood to be inclusive, although all or a subset of the components and / or steps may alternatively be exclusive and may be expressed as "consisting of" or alternatively "consisting essentially of" the various components, steps, subcomponents, or substeps.

[0055]

[0074] As used in this specification and claims, including those used in the examples, and unless otherwise expressly specified, all numbers may be read as if preceded by the word "about" or "approximately," even if the term does not explicitly appear. The phrase "about" or "approximately" may be used when describing a size and / or location to indicate that the stated value and / or location is within a reasonably expected range of value and / or location. For example, numerical values ​​may include values ​​of + / -0.1% of the stated value (or range of values), + / -1% of the stated value (or range of values), + / -2% of the stated value (or range of values), + / -5% of the stated value (or range of values), + / -10% of the stated value (or range of values), etc. Any numerical value given herein should also be understood to include about or approximately that value unless the context dictates otherwise. For example, if the value "10" is disclosed, then "about 10" is also disclosed. Any numerical range recited herein is intended to include all subranges therein. As would be appreciated by one of ordinary skill in the art, when a value is disclosed, it is understood that "less than or equal to" the value, "greater than or equal to" the value, and possible ranges between the values ​​are also disclosed. For example, if a value "X" is disclosed, "less than or equal to X" and "greater than or equal to X" (e.g., where X is a numeric value) are also disclosed. It is also understood that throughout this application, data is provided in a number of different formats, and this data represents endpoints and starting points, and ranges for any combination of the data points. For example, if a specific data point "10" and a specific data point "15" are disclosed, it is understood that values ​​greater than, equal to, less than, less than, or equal to 10 and 15, and values ​​equal to 10 and 15 are considered to be disclosed, as are values ​​between 10 and 15. It is also understood that each unit between two specified units is also disclosed. For example, if 10 and 15 are disclosed, then 11, 12, 13, and 14 are also disclosed.

[0056]

[0075] While various exemplary embodiments have been described above, any of a number of modifications can be made to the various embodiments without departing from the scope of the invention as set forth in the claims. For example, the order in which the various described method steps are performed can often be changed in alternative embodiments, and in other alternative embodiments, one or more method steps may be omitted entirely. Optional features of the various device and system embodiments may be included in some embodiments and not in other embodiments. Accordingly, the foregoing description has been provided primarily for illustrative purposes and should not be construed as limiting the scope of the invention as set forth in the claims.

[0057]

[0076] The examples and figures included herein illustrate, by way of illustration, not limitation, specific embodiments in which the subject matter may be practiced. As noted above, other embodiments may be utilized and derived therefrom, such that structural and logical substitutions and changes may be made without departing from the scope of the present disclosure. Such embodiments of the inventive subject matter may be referred to herein individually or collectively by the term "invention" for convenience only, and are not intended to intentionally limit the scope of the present application to any single invention or inventive concept, even if multiple inventions are actually disclosed. Thus, while specific embodiments have been shown and described herein, any configurations calculated to achieve the same purpose may be substituted for the specific embodiments shown. The present disclosure is intended to cover any adaptations or variations of the various embodiments. Combinations of the above embodiments, as well as other embodiments not specifically described herein, will be apparent to those skilled in the art upon reviewing the above description.

Claims

1. 1. A universal respiration detector for detecting respiratory gases and indicating a respiration status based on said gases, comprising: a first side and a second side opposite the first side; a cover layer on the first side; a respiratory sensor layer including a backing and a visual indicator on the backing, the visual indicator configured to reversibly change color to indicate a change in color when a respiratory gas parameter changes, the color change being visible from both the first side and the second side, and the cover layer covering at least a portion of the backing; an adhesive ring on the second side that adheres the respiratory sensor layer to the cover layer, the adhesive ring including a central region configured to allow exhaled air to flow therethrough; Including, the respiratory sensor layer is at least partially disposed between the cover layer and the adhesive ring. General-purpose breath detector.

2. the universal breath detector comprises a sticker; 10. The universal breath detector of claim 1.

3. comprising a low off-gassing adhesive, a no off-gassing adhesive, a silicone adhesive, a low volatile organic compound adhesive (low VOC), and / or a low volatile organic compound adhesive (low VOC) acrylic on the adhesive ring; A general-purpose breath detector according to claim 1 or 2.

4. a biocompatible adhesive on the cover; a release liner on top of the biocompatible adhesive; and further comprising: A general-purpose breath detector according to any one of claims 1 to 3.

5. the backing comprises polyethersulfone, polysulfone, or polyphenylenesulfone; A universal breath detector according to any one of claims 1 to 4.

6. including a maximum thickness of less than 0.1 inches (0.254 cm); A universal breath detector according to any one of claims 1 to 5.

7. including a longest dimension of less than about 1 inch (2.54 cm), A universal breath detector according to any one of claims 1 to 6.

8. the visual indicator is configured to reversibly change color in response to carbon dioxide; A universal breath detector according to any one of claims 1 to 7.

9. the universal breath detector is biocompatible; A universal breath detector according to any one of claims 1 to 8.

10. The adhesive ring includes a transparent or translucent membrane therein. A universal breath detector according to any one of claims 1 to 9.

11. The visual indicator is Reversibly change color when respiratory gas parameters change, The color change is displayed for a period lasting at least 10 minutes, at least 1 hour, at least 10 hours, at least 1 day, at least 3 days, at least 1 week, or at least 2 weeks. It is configured as follows: A universal breath detector according to any one of claims 1 to 10.

12. It is non-metallic, latex-free, and configured to be single-use and disposable; A universal breath detector according to any one of claims 1 to 11.

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