US20070106134A1 - Medical sensor and technique for using the same - Google Patents
Medical sensor and technique for using the same Download PDFInfo
- Publication number
- US20070106134A1 US20070106134A1 US11/441,583 US44158306A US2007106134A1 US 20070106134 A1 US20070106134 A1 US 20070106134A1 US 44158306 A US44158306 A US 44158306A US 2007106134 A1 US2007106134 A1 US 2007106134A1
- Authority
- US
- United States
- Prior art keywords
- tissue
- set forth
- gas collection
- sensing component
- constituent
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
Images
Classifications
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/08—Detecting, measuring or recording devices for evaluating the respiratory organs
- A61B5/083—Measuring rate of metabolism by using breath test, e.g. measuring rate of oxygen consumption
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/08—Detecting, measuring or recording devices for evaluating the respiratory organs
- A61B5/097—Devices for facilitating collection of breath or for directing breath into or through measuring devices
Abstract
A sensor is provided that is appropriate for transcutaneous detection of tissue or blood constituents. A sensor for tissue constituent detection may include a gas collection chamber with a conduit to a sensing component and a conduit from the sensing component to the chamber. A sensor as provided may also include a barrier layer to prevent water from infiltrating the sensor.
Description
- This application claims priority to U.S. Provisional Application No. 60/735,621, filed Nov. 10, 2005, the disclosure of which is hereby incorporated by reference.
- 1. Field of the Invention
- The present invention relates generally to medical devices and, more particularly, to sensors used for sensing physiological parameters of a patient.
- 2. Description of the Related Art
- This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the present invention, which are described and/or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present invention. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.
- In the field of medicine, doctors often desire to monitor certain physiological characteristics of their patients. Accordingly, a wide variety of devices have been developed for monitoring many such characteristics of a patient. Such devices provide doctors and other healthcare personnel with the information they need to provide the best possible healthcare for their patients. As a result, such monitoring devices have become an indispensable part of modern medicine.
- Physiological characteristics that physicians may desire to monitor include constituents of the blood and tissue, such as oxygen and carbon dioxide. For example, abnormal levels of carbon dioxide in the blood may be related to perfusion problems. Thus, assessment of carbon dioxide levels may be useful for diagnosing a variety of clinical states related to the circulation. Carbon dioxide and other blood constituents may be directly measured by taking a blood sample, or may be indirectly measured by assessing the concentration of those constituents in the tissue or respiratory gases. For example, carbon dioxide in the bloodstream equilibrates rapidly with carbon dioxide in the lungs, and the partial pressure of the carbon dioxide in the lungs approaches the amount in the blood during each breath. Accordingly, physicians often monitor respiratory gases during breathing in order to estimate the carbon dioxide levels in the blood.
- However, estimation of carbon dioxide by respiratory gas analysis has certain disadvantages. It is often inconvenient to measure carbon dioxide in samples collected from an intubation tube or cannula. Although these methods are considered to be noninvasive, as the surface of the skin is not breached, the insertion of such devices may cause discomfort for the patient. Further, the insertion and operation of such devices also involves the assistance of skilled medical personnel.
- Carbon dioxide in the blood that diffuses into the tissue may also be measured transcutaneously by sensors placed against a patient's skin. While these sensors are easier to use than respiratory gas sensors, they also have certain disadvantages. For example, these sensors may be sensitive to the infiltration of water or bodily fluids, particularly when applied to a mucosal surface.
- Certain aspects commensurate in scope with the originally claimed invention are set forth below. It should be understood that these aspects are presented merely to provide the reader with a brief summary of certain forms of the invention might take and that these aspects are not intended to limit the scope of the invention. Indeed, the invention may encompass a variety of aspects that may not be set forth below.
- There is provided a system that includes: at least one gas collection chamber into which a tissue constituent is able to diffuse, wherein the gas collection chamber is adapted to be placed proximate to a tissue; an efferent conduit adapted to transfer the tissue constituent from the gas collection chamber to at least one sensing component, wherein the sensing component is adapted to provide a signal related to the tissue constituent; an afferent conduit adapted to transfer the tissue constituent from the sensing component to the gas collection chamber; and a motive force structure adapted circulate the tissue constituent through the system, wherein the motive force structure is adapted to be operatively connected to at least one of the efferent conduit, the afferent conduit, or the sensing component.
- There is also provided a monitoring device that includes: a monitor; and a system adapted to be coupled to the monitor, the system including: at least one gas collection structure adapted to be placed proximate to a tissue; and an efferent conduit adapted to transfer gas from the gas collection structure to a sensing component, wherein the sensing component is adapted to provide a signal related to a tissue constituent; and an afferent conduit adapted to transfer gas from the sensing component to the gas collection structure.
- There is also provided a method that includes: transferring a tissue constituent in a gas collection chamber to at least one sensing component not located in the gas collection chamber, wherein the sensing component is adapted to provide a signal related to the tissue constituent.
- There is also provided a sensing system component that includes: at least one gas collection chamber into which a tissue constituent is able to diffuse, wherein the gas collection chamber is adapted to be placed proximate to a tissue; a first conduit in communication with the gas collection chamber comprising a connector located distally from the gas collection; and a second conduit in communication with the gas collection chamber comprising a connector located distally from the gas collection chamber.
- There is also provided a method of manufacturing a sensing system component that includes: providing at least one gas collection chamber into which a tissue constituent is able to diffuse, wherein the gas collection chamber is adapted to be placed proximate to a tissue; providing a first conduit in communication with the gas collection chamber comprising a connector located distally from the gas collection; and providing a second conduit in communication with the gas collection chamber comprising a connector located distally from the gas collection chamber.
- There is also provided a sensor that includes: a sensor body comprising at least one gas collection chamber adapted to be placed proximate to a tissue; a sensing component disposed on the sensor body adapted to provide a signal related to a tissue constituent; and a barrier layer defining at least part of a surface of the gas collection chamber, wherein the barrier layer is substantially impermeable to water.
- There is also provided a system that includes: a monitor; and a sensor adapted to be coupled to the monitor, the sensor including: a sensor body comprising a gas collection chamber adapted to be placed proximate to a tissue; a sensing component disposed on the sensor body adapted to provide a signal to the monitor related to a tissue constituent; and a barrier layer defining at least part of a surface of the gas collection chamber, wherein the barrier layer is substantially impermeable to water.
- There is also provided a method of measuring a tissue constituent that includes: diffusing a tissue constituent through a barrier layer that is substantially impermeable to water, wherein the barrier layer defines at least part of a surface of a gas collection chamber; and providing a signal related to the tissue constituent with a sensing element disposed on the gas collection chamber.
- There is also provided a method of manufacturing a sensor that includes: providing a sensor body comprising a gas collection chamber adapted to be placed proximate to a tissue; providing a sensing component disposed on the sensor body adapted to provide a signal related to a tissue constituent; and providing a barrier layer defining at least part of a surface of the gas collection chamber, wherein the barrier layer is substantially impermeable to water.
- Advantages of the invention may become apparent upon reading the following detailed description and upon reference to the drawings in which:
-
FIG. 1 illustrates a perspective view of a patient using a sensor for detection of a physiological tissue constituent according to the present invention; -
FIG. 2 is a schematic cross-sectional view of the sensor ofFIG. 1 ; -
FIG. 3A illustrates a schematic view of an embodiment of a sensor according to the present techniques; -
FIG. 3B illustrates a view of an exemplary disposable portion of the sensor ofFIG. 3A ; -
FIG. 4 is a flow chart of a method of operating a sensor according to the present invention; -
FIG. 5A-5B illustrate an alternate configuration of a tissue constituent collection portion of a sensor according to the present techniques; -
FIG. 7 illustrates a perspective view of a patient using a sensor including a barrier layer for detection of a physiological tissue constituent according to the present invention; -
FIG. 8 is a schematic cross-sectional view of the sensor ofFIG. 7 ; -
FIG. 9 is a sensor including multiple collection chambers for tissue constituent detection; and -
FIG. 10 illustrates a physiological constituent detection system coupled to a multi-parameter patient monitor and a sensor according to embodiments of the present invention. - One or more specific embodiments of the present invention will be described below. In an effort to provide a concise description of these embodiments, not all features of an actual implementation are described in the specification. It, should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions must be made to achieve the developers' specific goals, such as compliance with system-related and business-related constraints, which may vary from one implementation to another. Moreover, it should be appreciated that such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure.
- A sensor and/or sensing system is provided herein that may assess a tissue constituent content with a sensing component that is adapted to provide a signal related to the tissue constituent. In certain embodiments of the invention, the sensing system may include a collection chamber placed against the tissue and a sensing component that is connected to the chamber by a conduit with a return conduit between the sensing component and the collection chamber. The collection chamber is able to capture a volume of volatile tissue constituents as they diffuse out of the tissue. When the concentration of the tissue constituents in the gas collection chamber and throughout the sensing system is substantially equal to the concentration of those constituents in the tissue, the sensing system is equilibrated
- Such a system may provide multiple advantages. By separating the sensing component from the tissue constituent collection chamber, a sensor may be more versatile. For example, a sensing component may be easily exchanged for an alternate sensing component without disrupting the collection of the tissue constituent. This may be advantageous when a sensing component needs to be maintained or serviced, and the healthcare provider does not wish to disrupt physiological monitoring while replacing the sensing component. Additionally, the separation of the sensing component from the tissue constituent collection chamber may help reduce water infiltration into the sensing component.
- Sensors according to the present techniques may transcutaneously sense tissue gases or other tissue constituents in a tissue layer and provide an electrical and/or visual signal. For example, carbon dioxide and other constituents in the bloodstream may diffuse through the tissue and may dissolve into any liquids that may be found at the surface of the tissue. Thus, the levels of carbon dioxide in the tissue may serve as a surrogate marker for carbon dioxide levels in the bloodstream. A sensor according to the present techniques placed proximate to a tissue surface may capture and measure carbon dioxide that would otherwise diffuse into the airstream or other surrounding airspace.
- Generally, it is envisioned that sensors according to the present techniques are appropriate for use in determining the presence or levels of tissue constituents in a variety of tissues. The sensor may be placed against the tissue, either manually, mechanically, adhesively, or otherwise, forming a seal to prevent the carbon dioxide from diffusing away. For example, a sensor may be used in the upper respiratory tract or the gastrointestinal tissue, including the oral and nasal passages. These passages may include the tongue, the floor of the mouth, the roof of the mouth, the soft palate, the cheeks, the gums, the lips, the esophagus and any other respiratory or gastrointestinal tissue. Further, a sensor as described herein is appropriate for use adjacent to or proximate to any mucosal surface, i.e., patient surfaces that include a mucous membrane or surfaces that are associated with mucus production. In addition to the respiratory tract, mucosal surfaces may include vaginal, rectal, or gastrointestinal surfaces.
- Sensors as provided by the present techniques may be disposable, reusable, or partially disposable. In addition, the sensors may be appropriate for short-term or for longer-term monitoring. When used for long-term monitoring, the sensor may be applied to the patient's tissue either by mechanical clamping or by a suitable adhesive, such as a mucoadhesive, or by any other suitable holding device, such as a clip.
- In additional to carbon dioxide monitoring, sensors and sensing systems as provided herein may be used to monitor oxygen, carbon monoxide, ethanol, or anesthetic gases (such as isoflurane, halothane, desflurane, sevoflurane and enflurane) that may diffuse transcutaneously. Additionally, these sensors and/or sensing systems may be used to monitor volatile products of metabolism (such as ketones, alcohols, lactones, terpenes, furans, dimethyl sulfone, pyrrole, and allyl isothiocyanate), as well as volatile xenobiotics and their metabolites. Further, these sensors may be useful in monitoring the levels of parenterally administered or enterally administered therapeutic agents.
- For example,
FIG. 1 illustrates the placement of agas collection chamber 12 of asensor 10 on a buccal surface in order to assess a tissue gas, for example carbon dioxide, in the tissue, blood or interstitial fluid. Specifically,FIG. 1 shows an embodiment of asensor 10 including agas collection chamber 12 and a conduit 14 in communication with asensing component 16. The conduit 14 may be adapted to transport gases from thegas collection chamber 12 to adistal sensing component 16. The collected gases may diffuse through theefferent conduit 14 a that is connected to the collection chamber, and the gases may then be further assessed and/or measured by thesensing component 16, discussed in more detail below. The collected gases may then circulate back to thegas collection chamber 12 through theafferent conduit 14 b. Thegas collection chamber 12 may be suitably sized and shaped such that a patient may easily close his or her mouth around the sensor with minimal discomfort. - The
gas collection chamber 12 is secured to themucosal tissue 18 such that the area covered by thegas collection chamber 12 creates aseal 13 to prevent environmental air flow out or into of thegas collection chamber 12, thus preventing tissue gases at thegas collection chamber 12 placement site from dissipating into the airstream or being diluted, which may lead to inaccurate measurements. Further, the gas collection chamber's 12 tissue seal may also prevent respiratory gases or oral fluids from entering thesensor 10A. -
Tissue constituents 22 may be transferred through a conduit 14, which may include tubes or tube segments. The conduit 14 may include, for example, medical grade catheter tubing, polyethylene, polypropylene or vinyl. Theefferent conduit 14 a and theafferent conduit 14 b may be disposed on any appropriate location on thegas collection chamber 12. For example, theefferent conduit 14 a and theafferent conduit 14 b may be parallel or perpendicular to each other. Generally, the conduit 14 may be relatively impermeable to the tissue constituent. This may be accomplished by selecting a conduit 14 made from an appropriate material or by applying a sealing coat to the conduit 14. The conduit 14 may include gas-impermeable plastics such as PET. Appropriate gas-impermeable coatings may include Funcosil® (available from Remmers, Loeningen, Germany). Such coatings may be applied to the conduit 14 in any appropriate manner. - A cross-sectional view of the
sensor 10A is shown inFIG. 2 . Thehousing 20 is formed to provide a surface that is suitably shaped to be secured against amucosal tissue 18. Thehousing 20 may be any suitable material that is generally suited to the aqueous environment of the mucous membrane. For example, thehousing 20 may be formed from polypropylene, polyethylene, polysulfone or similar polymers. Generally, thehousing 20 should be substantially impermeable to tissue constituents, shown byarrows 22, such that thesensor 10A may collecttissue constituents 22, such as tissue gases, for a sufficient period of time to allow for detection and measurement. Hence, it may be advantageous to coat thesensor 10A with additional sealants to prevent leakage of thetissue constituents 22. Thehousing 20, once secured to the tissue, forms acollection chamber 12 that trapstissue constituents 22 that diffuse through themucosal tissue 18. The trappedtissue gas 22 may then be transferred to thesensing component 16, which is coupled thegas collection chamber 12 by theefferent conduit 14 a. - In the depicted embodiment, the
sensing component 16 is not located on or within thegas collection chamber 12. When thehousing 20 is contacted with a tissue sensor site, blood ortissue constituents 22 perfuse through the tissue and enter thecollection chamber 12. Thesensing component 16 is adapted to respond to the presence of the blood ortissue constituents 22 collected in thegas collection chamber 12 and to provide a signal, as discussed in more detail below. Thesensing component 16 is sensitive to the presence of atissue constituent 22 and may be capable of being calibrated to give a response signal corresponding to a given predetermined concentration of the tissue constituent. In certain embodiments, the signal may be related to the concentration or level of thetissue constituent 22, or the partial pressure of thetissue constituent 22. - In certain embodiments, the
gas collection chamber 12 may include materials that function as abarrier layer 28 that are hydrophobic or otherwise water-resistant, but that are permeable to carbon dioxide. For example, abarrier layer 28 may form a contact surface of thesensor 10A that prevents water from entering thesensor 10A. In such an embodiment, carbon dioxide in the tissue can perfuse through the contact surface to enter thegas collection chamber 12. In one embodiment, it is envisioned that the ratio of water permeability to carbon dioxide permeability of abarrier layer 28 may be less than 1:1, and in certain embodiments, the ratio may be less than 1:10. Suitable materials include polymers, such as polytetrafluorethylene (PTFE). Other suitable materials include microporous polymer films, such as those available from the Landec Corporation (Menlo Park, Calif.). Such microporous polymer films are formed from a polymer film base with a customizable crystalline polymeric coating that may be customized to be highly permeable to carbon dioxide and relatively impermeable to water. In one embodiment, thebarrier layer 28 may be a relatively thin PTFE material such as plumber's tape (0.04 mm). In other embodiments, thebarrier layer 28 may be a PTFE material such as Gore-Tex® (W. L. Gore & Associates, Inc., Newark, Del.) or plumber's tape. Alternatively, thebarrier layer 28 may be formed from a combination of appropriate materials, such as materials that are heat-sealed or laminated to one another. For example, thebarrier layer 28 may include a PTFE layer with a pore size of 3 microns and a second PTFE layer with a pore size of 0.1 microns. Additionally, in certain embodiments, asensor 10A may also include a porous substrate 29 that is permeable to a wide variety oftissue constituents 22. As abarrier layer 28 may be quite thin, the porous substrate may be advantageous in providing rigidity and support to thebarrier layer 28 film. The porous substrate may be adhered, laminated, or otherwise attached to thebarrier layer 28. In certain embodiments, the porous substrate may be disposed on the tissue-contacting side of thebarrier layer 28. Suitable materials for the porous substrate include paper, plastics, or woven materials. - In certain embodiments, the
barrier layer 28 or porous substrate 29 may include a tissue irritant or other agent or structure that increases blood flow to the tissue at thegas collection chamber 12 placement site. The agent may include a counterirritant, such as a mixture of methyl salicilate and menthol (12% methyl salicilate, 9% menthol) in a cream base is applied to the patient's skin at the chosen sensor site. A cream of this type is sold in retail drug stores under the trademark ICY HOT. Other contemplated agents of this type may include heaters, such as mechanical or chemical heaters, that increase blood perfusion in response to lowered tissue temperatures. - The
sensing component 16 may be disposed on or within any appropriate substrate that provides a suitable contact area with which thetissue constituent 22 may interact, react, or otherwise come into the proximity of thesensing component 16. For example, in embodiments in which the sensing component includes a chemical indicator, it may be appropriate to include, as part of a holder for thesensing component 16, a transparent viewing window for the healthcare provider to view a change in color of the indicator. In embodiments in which the sensing component includes an optical detection system, it may be appropriate to dispose the sensing component in a chamber. - Although the
tissue constituent 22 may diffuse and circulate through the conduit 14 to thesensing component 16 without a drawing force, such a process may be lengthy. Thus, it may be advantageous to provide a motive device, such as a pump, within the sensor.FIG. 3 is a schematic diagram of theexemplary sensor 10A that provides a pumping andsensing component system 33 to draw thetissue constituent 22 to thesensing component 16. Aflow regulator 32, which may be a valve or any other suitable device, and pump 34 are connected into or between segments of conduit 14 to maintain a desired flow velocity of the stream of tissue constituent 22 to thesensing component 16. As shown, theflow regulator 32 is connected to apump 34. Thepump 34 is in turn interposed between sections of the conduit 14, which is connected to thesensing component 16. - The ends of the conduit 14 segments may be secured to connectors 30, as shown in
FIG. 3 , which may be clamped to prevent leaking of thetissue constituent 22 to the outside.Connectors sensor 10A, including theflow regulator 32, pump, 34, orsensing component 16. - In certain embodiments, it may be advantageous to exchange a
first sensing component 16 adapted to sense carbon dioxide for asecond sensing component 16. Thesecond sensing component 16 may also sense carbon dioxide, but may operate by a different sensing mechanism. Alternatively, thesecond sensing component 16 may be adapted to sense a different tissue constituent, such as carbon monoxide or oxygen. Further, in an alternate embodiment (not shown), thesensor 10A may havemultiple sensing components 16 in series. - In certain embodiments, the
pump 34 andflow regulator 32 may be adjusted so that the flow is maintained at the desired rate. One suitable flow regulator is orifice/needle valve model F-2822-41-B80-55 available from Air Logic, Racine, Wis., which can be adjusted to obtain a desired gas flow rate in the range of up to 40-60 m/min. One suitable pump is model NMP 05 diaphragm micro pump, available from KNF Neuberger, Inc, Princeton, N.J., which has a free flow capacity of 0.4 L/min. Thepump 34 andflow regulator 32 may be located anywhere in the flow stream of thesensor 10A. Generally, the pumping system is substantially sealed to prevent leaking of thetissue constituent 22 to the outside or dilution by entraining of fresh gas. In other embodiments, any suitable motive force structure may be appropriate for use with the present techniques. For example, suitable motive force structures include gravity pumps, one-way valves, kinetic motion pumps, or piezoelectric pumps. - In certain embodiments, the
pump 34,flow regulator 32, andsensing component 16 may be connected to aprocessor 40. The processor may be part of a monitor or multi-parameter monitor, as discussed in detail below. Theprocessor 40 may receive signals related to the output signals from sensingcomponent 16, corresponding to thetissue constituent 22 concentration or partial pressure concentration. Additionally, theprocessor 40 may control the flow of the vacuum andsensing component system 33. It should be understood that theprocessor 40 may be adapted to determine a suitable equilibration time of thesensor 10A by comparing the equilibration time to stored equilibration curves that may be empirically obtained. Additionally, in certain embodiments, the concentration of thetissue constituent 22 may be extrapolated from a concentration curve obtained by thesensor 10A during the pre-equilibration period, as such a curve will start to plateau as it approaches the equilibrated state. - In certain embodiments, the
gas collection chamber 12, the conduit 14, or the connectors 30 may include acalibration element 42, such as a coded resistor or EEPROM or other coding devices (such as a capacitor, inductor, PROM, RFID, a barcode, parallel resonant circuits, or a colorimetric indicator) that may provide a signal to theprocessor 40 related to the volume and other characteristics of thegas collection chamber 12 that may allow theprocessor 40 to determine the appropriate calibration characteristics for thesensor 10A. Generally, such acalibration element 42 may be located on a disposable portion of thesensor 10A, shown inFIG. 3B , that may include thegas collection chamber 12, the conduit segments 14 attached to thegas collection chamber 12, or any connectors 30 proximate to thegas collection chamber 12. In such an embodiment, for example when the calibration element is disposed on the connector 30 as shown, the connector 30, conduit segment 14, and thecalibration element 42 may be constructed as a unitary assembly such that thecalibration element 42 may be inseparable from thegas collection chamber 12. Further, thecalibration element 42 may include encryption coding that prevents a disposable part of thesensor 10A from being recognized by aprocessor 40 that is not able to decode the encryption. Such encryption coding is described in U.S. Pat. No. 6,708,049, which is hereby incorporated by reference in its entirety. - The
sensing component 16 may also include a calibration element (not shown) that provides information to theprocessor 40 that may include the type of tissue constituent 22 that is being analyzed or other characteristics of thesensing component 16. For example, such asensing component 16 calibration element may send a signal to theprocessor 40 to employ a certain correction algorithm for calculating the concentration of thetissue constituent 22. Such a correction algorithm may be appropriate when thesensing component 16 includes a chemical indicator that consumes a percentage of thetissue constituent 22 while actively measuring it. As the consumption of thetissue constituent 22 by thesensing component 16 may alter the equilibration state of thesensor 10A, the correction algorithm may mitigate such effects on thesensing component 16 output signal. In an alternative embodiment, a correction algorithm may also be employed if asensing component 16 generated thetissue constituent 22 during measurement. Further, a correction algorithm may account for any minimal leakage of tissue constituent 22 in the system. - The
collection chamber 12 is part of a substantially closed environment, as the conduit 14, and thesensing component 16 are generally impermeable to thetissue constituent 22 of interest. Thesensor 10A is permeable to thetissue constituent 22 where thecollection chamber 12 contacts thetissue 18. When the partial pressure of thetissue constituent 22 in thesensor 10A is substantially equal to the partial pressure of the tissue constituent in thetissue 18, thesensor 10A is equilibrated. Thesensor 10A is arranged to provide circulating flow of thetissue constituent 22 through thesensor 10A. Thus, thetissue constituent 22 may equilibrate throughout thesensor 10A while being transferred from thegas collection chamber 12 through theefferent conduit 14 a to contact thesensing component 16, and may return to thegas collection chamber 12 through theafferent conduit 14 b. Such an embodiment may be advantageous when atissue constituent 22 is being continuously or regularly monitored. As the initial application of thegas collection chamber 12 to the mucosal tissue 26 may involve waiting for 5-10 minutes before thetissue constituent 22 equilibrates in the gas collection chamber prior to being analyzed, it is desirable to keep the sensor in the equilibrated state. In such an embodiment, thevent 38 to the outside may be closed during equilibration andtissue constituent 22 monitoring. Thevent 38 may be opened when necessary in order to flush out the sensor with room air or purge gas. - The equilibration time of the
sensor 10A may be influenced by certain factors. Generally, equilibration times may be in the range of substantially instantaneous, i.e., real time, to less than 5 minutes. In certain embodiments, the response time is in the range of 5 seconds to 30 minutes. For example, in certain embodiments, the thickness of abarrier layer 28 may be modified in order to achieve the desired rate of carbon dioxide perfusion andsensing component 16 response time. Where a very rapid response is desired, a thin film of thebarrier layer 28, for example less than 0.2 mm in thickness, may be used. Additionally, thebarrier layer 28 may be formed with small pores that increase the carbon dioxide permeability. In other embodiments, the response time may be influenced by the volume of thegas collection chamber 12 or the length and diameter of the conduit 14. It is envisioned that the volume of thegas collection chamber 12 may be optimized to be large enough to allowsufficient tissue constituents 22 to be collected to obtain accurate measurements while being small enough to provide rapid response times. For example, in certain embodiments, the total volume of the gas collection chamber may be 0.2-5.0 cubic centimeters. It may be appropriate to use a relatively smaller, e.g., 0.2-0.8 cubic centimeters, gas collection chamber on a neonate. In certain embodiments, the total volume of thesensor 10A, including the conduit 14,sensing component 16, and pumpingsystem 33 may be 2-500 cubic centimeters. Generally,smaller sensor 10A volumes are associated with faster equilibration times. - Referring to
FIG. 4 , aflow chart 44 illustrates how atissue constituent 22 may be analyzed by thesensor 10A. Agas collection chamber 12 is applied to a patient's mucosal tissue (block 46) and thetissue constituent 22 diffuses into thegas collection chamber 12. Thepump 34 and/orflow regulator 32 is then activated, either by the healthcare provider or by a processor 40 (block 49 and thetissue constituent 22 equilibrates while being pumped through thesensor 10A. Thetissue constituent 22 is drawn into proximity withsensing component 16, and thesensing component 16 provides a signal related to the tissue constituent 22 (block 50). Thetissue constituent 22 may be circulated through the sensor (block 54) back to thegas collection chamber 12 in order to maintain the equilibrated state. - In certain embodiments, it may be advantageous to provide a sensor with a gas collection portion with a large surface area that contacts the tissue. Such a sensor may equilibrate more rapidly, as
tissue constituent 22 may diffuse more rapidly into the gas collection portion.FIGS. 5A-5B illustratesensors 10B with alternative gas collection configurations. InFIG. 5A , asensor 10B may include a gas collection portion in the form of a coiledtube 80, which may be coiled in the manner of a garden hose, that is permeable to thetissue constituent 22. The coiledtube 80 may increase the available surface area of the gas collection portion of thesensor 10B, as it may be adapted to lay flat against atissue 18. Thetissue constituent 22 diffuses into the coiledtube 80 and is drawn into theefferent conduit 14 a. Thetissue constituent 22 may be circulated throughconduit 14 b. Although the coiledtube 80 is permeable to thetissue constituent 22, the tissue constituent is able to equilibrate in the sensor as the coiledtube 80 may adapted to be substantially surrounded bymucosal tissue 18. For example, the coiledtube 80 may be placed sublingually. In an alternate embodiment, the coiledtube 80 may be adapted to be permeable only on one side by applying a tissue constituent impermeable coating (not shown) to certain portions of the coiledtube 80. Thus, once thetissue constituent 22 diffuses into the coiledtube 80, the partial pressure of thetissue constituent 22 in thesensor 10B may equilibrate with thetissue 18 without leaking out the portion of the coiledtube 80 not in contact with thetissue 18. Such a configuration may be appropriate for use on buccal tissue. In an alternate embodiment, shown inFIG. 5B , the tissue constituent permeable collection portion may assume azigzag configuration 82 connected to the conduit 14. Exposed portion of the substrate 84, i.e., portions not in contact with thetissue 18, may be coated with a tissue constituent impermeable coating 86 to prevent leaking. It should be understood that the configurations shown are merely exemplary, and the gas collection portions of thesensor 10B may take any suitable shape, such as a helix, a coiled coil, or other configurations. Appropriate permeable materials from which the permeable gas collection portions may be formed may include Silastic® silicone rubber, available from Dow Coming (Midland, Mich.). -
FIG. 6 illustrates a tissue constituent permeable coiledtube 80 connected to a pumping andsensing component system 33 byefferent conduit 14 a andafferent conduit 14 b.Efferent conduit 14 a is adapted to draw thetissue constituent 22 to thesensing component 16. The system may include acalibration element 81 as described herein that is adapted to communicate with theprocessor 40 and provide information related to the characteristics of the disposable portion of thesensor 10D, which may include the tissue constituent permeable coiledtube 80 and certain segments of the conduit 14. It is envisioned that any suitable tissue constituent permeable assembly as described herein may be connected to the pumping andsensing component system 33 as shown. - The sensors as provided herein may prevent water infiltration into a sensing component by arranging a sensor such that the sensing component is removed from the tissue and thus is removed from bodily fluids. However, in certain embodiments it may be advantageous to provide a unitary sensor configuration including a gas collection chamber on which or within which the sensing component is disposed. Such an arrangement may be easier to for a healthcare worker to apply and operate, as it does not involve a motive device. Additionally, such a sensor may be smaller and lighter, providing certain transportation and storage advantages. In such an embodiment, water infiltration into the sensor may be reduced by providing a sensor that includes a water barrier layer.
FIG. 7 -FIG. 8 illustrate an alternate embodiment of atissue constituent sensor 10D in which thesensor body 55 includes a sensing component disposed proximate to agas collection chamber 57.FIG. 7 shows the sensor applied to a patient.FIG. 8 shows a cross-sectional view of thesensor 10D. As depicted, water is prevented from infiltrating thesensor 10D by abarrier layer 58 as described herein that forms at least part of a surface of thesensor 10D that contacts the tissue. In an alternate embodiment (not shown), thesensor 10D may be configured to prevent water infiltration by a structure that absorbs and/or redirects water away from the sensing components. For example, thesensor 10B may include a water vapor permeable backflush tube that is selectively permeable to water vapor to allow water vapor to be absorbed and evaporate away from the sensing components without infiltrating the sensor. Such a tube may include a material such as Nafion (available from DuPont, Wilmington, Del.). Thebarrier layer 58 is connected to ahousing 56 that, when applied to themucosal tissue 28, forms a collection chamber that traps atissue constituent 22 that diffuses through thebarrier layer 58. It should be understood that thesensor 10D may include any sensing component as described herein. For example, sensing component may be an optical transducer. In such an embodiment, the trappedtissue constituent 22 may be irradiated by anemitter 60, and the emitted light that passes through the tissue constituent may be detected by adetector 62. Theemitter 60 and thedetector 62 are electrically coupled to acable 64 bywires 68. The wavelength of the light emitted by theemitter 60 and the detection range of thedetector 62 may be selected to detect a wide range oftissue constituents 22. For example, theemitter 60 may also include a filter, for example a 4.26 micron wavelength filter. Such a filter may be appropriate for use in an embodiment where carbon dioxide is measured. - In some embodiments, the
sensor 10D is arranged to operate in transmission mode, and casings for the emitter and detector may be formed in thehousing 56 on opposite sides of thesensor 10D. In an alternate embodiment, theemitter 60 and thedetector 62 may be arranged to operate in reflectance mode (not shown), and can be located on the same side ofsensor 10D. In such an embodiment (not shown), a mirror may be placed on the opposite side of thehousing 56 to reflect the radiation emitted from theemitter 60 back to thedetector 62. When employingoptical sensing components 16, it may be advantageous to dispose an opaque or reflective layer on the tissue-contacting surface of thesensor 10D to prevent signal artifacts as a result of the absorption of a portion of the emitted light by thetissue 18. - In certain embodiments (not shown), the
gas collection chamber 57 may include acalibration element 66 or other transducer that may provide a signal related to the volume and other characteristics of thegas collection chamber 57. Such acalibration element 66 may allow a downstream processor or monitor to determine a suitable amount of time to allow thesensor 10B to equilibrate (i.e. to allow thetissue constituent 22 to diffuse into the gas collection chamber 57) before obtaining accurate measurements related to thetissue constituent 22. Additionally, thecalibration element 66 may be a coded resistor or EEPROM or any other suitable device as described herein that provides information related to the calibration of any optical sensing components. Such acalibration element 66 may be advantageous in increasing manufacturing yield of thesensor 10D. For example, asensor 10D including such acalibration element 66 that provides information about the emission wavelength or wavelength range of theemitter 60 may be able to be more accurately calibrated for a wider range of potential emission wavelengths than a sensor lacking such acalibration element 66. - It may be advantageous to provide a
sensor 10E as a dipstick-like device with aholder 88 that has a familiar and comfortable shape that is easy to use. For example, water-resistant sensors as provided herein may be used in vivo by a patient much like an oral thermometer.FIG. 9 illustrates a cross-sectional view of asensor assembly 10E according to the present techniques. Such asensor 10E may be adapted to assess one ormore tissue constituents 22, as illustrated. Abarrier layer 90, as described herein, may reduce water infiltration into thesensor 10E. As illustrated, thesensor 10E includes multiple gas collection chambers, each of which may include adifferent sensing component 16. For example, sensingcomponents different tissue constituent 22. In certain embodiments, the different tissue constituents may be carbon dioxide, carbon monoxide, oxygen, and other diffusible gases or volatile compounds. Each of thesensing components 16 may be electrically coupled to adisplay 94 by wires 92. The display may then indicate the concentrations of thetissue constituents 22 as measured by thesensing components 16. In an alternate embodiment, thesensor 10E may include electrical input and output wires (not shown) that may extend along theholder 88 to couple to a cable, which may be connected to a patient monitor. In another alternate embodiment (not shown), such asensor 10E may be adapted to includedistal sensing components 16 as described herein and a motive force structure to draw thetissue constituent 22 into the distal sensing components. Further, in another alternate embodiment (not shown), thebarrier 90 may include a series of selectively permeable barriers specific for a variety oftissue constituents 22. Thus, each of thegas collection chambers 12 may only be permeable to a particular tissue constituent. - The
sensor 10E may be inserted into the oral passage and placed adjacent to amucosal tissue 18. Thesensor 10E may be suitably sized and shaped such that a patient may easily close his or her mouth around theholder 88 with minimal discomfort. In certain embodiments, thesensor 10E may be adapted to be held against the cheek or any other mucosal tissue. Theholder 88 may also include a handle portion that is accessible from outside the mouth and may be manipulated by the patient or a healthcare worker in order to properly position thesensor assembly 10E within the mouth. - Sensors as described herein may include any appropriate sensing component for assessing a tissue constituent, including chemical, electrical, optical, non-optical, quantum-restricted, electrochemical, enzymatic, spectrophotometric, fluorescent, or chemiluminescent indicators or transducers. In certain embodiments, the sensing component may include optical components, e.g. an emitter and detector pair that may be of any suitable type. For example, the emitter may be one or more light emitting diodes adapted to transmit one or more wavelengths of light in the red to infrared range, and the detector may one or more photodetectors selected to receive light in the range or ranges emitted from the emitter. Alternatively, an emitter may also be a laser diode or a vertical cavity surface emitting laser (VCSEL). An emitter and detector may also include optical fiber sensing components. An emitter may include a broadband or “white light” source, in which case the detector could include any of a variety of elements for selecting specific wavelengths, for example reflective or refractive elements or interferometers. These kinds of emitters and/or detectors would typically be coupled to the rigid or rigidified sensor via fiber optics. Alternatively, a sensor may sense light detected from the tissue is at a different wavelength from the light emitted into the tissue. Such sensors may be adapted to sense fluorescence, phosphorescence, Raman scattering, Rayleigh scattering and multi-photon events or photoacoustic effects. It should be understood that, as used herein, the term “light” may refer to one or more of ultrasound, radio, microwave, millimeter wave, infrared, visible, ultraviolet, gamma ray or X-ray electromagnetic radiation, and may also include any wavelength within the radio, microwave, infrared, visible, ultraviolet, or X-ray spectra.
- Alternatively, the sensing component may include an active ingredient of the indicating element, for example the active ingredient involved in providing the required response signal when exposed to a given concentration of carbon dioxide or other constituents. The active ingredient may be any indicator that is sensitive to the presence of carbon dioxide and that is capable of being calibrated to give a response signal corresponding to a given predetermined concentration of carbon dioxide. The signal may be visual, e.g. a change in color, or electrical. Indicators which provide a color change in a presence of carbon dioxide may include chromogenic pH-sensitive indicators and oxidation/reduction indicators.
- A chromogenic pH-sensitive indicator may provide a color change upon exposure to a given concentration of carbon dioxide or other metabolites in the presence of other ingredients of the element that provide the appropriate chemical conditions to induce the required color change. For such an indicator to be capable of giving a determination of carbon dioxide, it is typically used in combination with a suitable base that provides an alkaline solution. The hydroxyl ions or amine residues present in the alkaline solution react chemically with carbon dioxide to produce a carbonate, bicarbonate and/or carbamate moiety. The resulting reaction depletes the hydroxyl ion or amine at the interface and thus lowers the pH at the surface of the component impregnated with the indicating element. The lowering of the pH causes a color change in the indicator.
- Chromogenic pH-sensitive indicators according to the present techniques may include metacresol purple, thymol blue, cresol red, phenol red, xylenol blue, a 3:1 mixture of cresol red and thymol blue, bromthymol blue, neutral red, phenolphthalein, rosolic acid, alpha-naphtholphthalein and orange I. Examples of other indicators which may be used include bromcresol purple, bromphenol red, p-nitrophenol, m-nitrophenol, curcumin, quinoline blue, thymolphthalein and mixtures thereof. Suitable bases include sodium carbonate, lithium hydroxide, sodium hydroxide, potassium hydroxide, potassium carbonate, sodium barbitol, tribasic sodium phosphate, dibasic sodium phosphate, potassium acetate, monoethanolamine, diethanolamine and piperidine.
- The sensing component may include a semi-conductive sensing element, such as an ion-sensitive field-effect transistor (ISFET). An ISFET may include a silicon dioxide gate for a pH selective membrane. Such a sensor may be adapted to sense downstream changes in hydrogen ion concentration in response to changes in carbon dioxide or other tissue constituent concentrations.
- The sensing component may also include an enzyme-based detection system. For example, one such enzyme may be carbonic anhydrase, which is an enzyme that assists interconversion of carbon dioxide and water into carbonic acid, protons, and bicarbonate ions. As described above, this reaction lowers the pH at the surface of the component impregnated with the indicating element. The lowering of the pH may cause a color change in the indicator. Another such enzyme-based detection system is an enzyme linked immunosorbent assay (ELISA). For example, such an assay may be appropriate when assessing tissue proteins. Thus, the indicator element may include a primary antibody specific for the tissue protein of interest, and a labeled secondary binding ligand or antibody, or a secondary binding ligand or antibody in conjunction with a labeled tertiary antibody or third binding ligand. The label may be an enzyme that will generate color development upon incubating with an appropriate chromogenic substrate. Suitable enzymes include urease, glucose oxidase, alkaline phosphatase or hydrogen peroxidase.
- A chemical indicator may be used in conjunction with an electrical or electronic device that is adapted to detect and measure changes in the ambient chemical parameters induced by the presence of critical amounts of carbon dioxide. For example, optical fiber carbon dioxide sensors may be used to convert a change in a chemical indicator to a quantitative measurement of carbon dioxide in the sample. Generally, such sensors operate by directing light of a predetermined wavelength from an external source through the optical fiber to impinge the chemical indicator. The intensity of the emitted fluorescent light returning along the fiber is directly related to the concentration of carbon dioxide in the sample, as a result of the pH-sensitive indicator material present at the fiber tip (i.e., the pH of the indicator solution is directly related to carbon dioxide concentration, as a result of carbonic acid formation). The emitted light is carried by the optical fiber to a device where it is detected and converted electronically to a carbon dioxide concentration value. The sensor may additionally have a reference dye present in the indicator composition. The intensity of the light emitted form the reference dye may be used to compensate, via rationing, the signal obtained from the indicator. Other components may be incorporated into the indicator composition including surfactants, antioxidants and ultraviolet stabilizers may also be present in the indicator composition. The sensing component may be formed from any appropriate substrate. For example, the sensing component may be filter paper, which may be soaked in, dipped in, or otherwise exposed to the appropriate carbon dioxide-sensing compounds. In certain embodiments, the filter paper may be dipped into a solution containing the indicating compounds on only one side. The sensing component may also be polysulfone, polyproplylene, or other polymer substrates. The sensing component may be a thin film, or a thicker substrate. A thicker substrate may lead to a slower response time, which may be advantageous in situations in which a sensor is monitoring carbon dioxide levels over a longer period of time. Additionally, the sensing component may have pores of a variety of sizes.
- The sensing component may include an electrochemical transducer, which may be adapted to detect and measure changes in ambient chemical parameters induced by the presence of critical amounts of a tissue constituent. In one embodiment, the sensing component may include a sensor that employs cyclic voltammetry for carbon dioxide detection. Such sensors are available from Giner, Inc., Newton, Mass. For example, the sensing component may be a thick film catalyst sensor utilizing a proton exchange membrane. Such a sensing component may include thick film screen printed electrodes and an electrochemically reversible metal oxide catalysts. Appropriate catalysts include MO, M2O3, MO2, where M is a metal that is any suitable metal, including platinum ruthenium or iridium. Generally, such sensors operate by sensing chemical reactions caused by proton dissociation from water in which carbon dioxide is dissolved. Dissociated water protons may electrochemically reduce a metal oxide layer of the sensor. The electrochemical reduction of the metal oxide will result in generation of an electrical current, which varies in response to the degree of electrochemical reduction.
- In another embodiment, the sensing component may include an artificial nose assembly. In such an embodiment, the tissue constituents may contact an array of electrodes coated with polymers that have characteristic electrical properties. The polymers change electrical resistance when contacted with specific volatile materials.
- In another embodiment, the sensing component may include quantum-restricted components, including carbon nanotubes, buckeyballs, or quantum dots. Generally, quantum-restricted components may be coated or otherwise modified with a compound that is sensitive to the tissue constituent of interest. Interaction of the tissue constituent with the compound may affect the electrical properties of the quantum-restricted components such that an electrical feedback may result. In one such example, carbon nanotubes may be coated with a carbon dioxide-sensitive compound or polymer, such as a polyethyleneimine and starch polymer. Carbon dioxide may combine with primary and tertiary amines in the polyethyleneimine and starch polymer coating to form carbamates. The chemical reaction lowers the pH of the polymer coating, altering charge transfer to the carbon nanotubes and resulting in an electrical signal proportional to the pH change. Other suitable polymer coatings may be adapted to sense other tissue constituents of interest, such as oxygen or carbon monoxide. In other embodiments, the quantum-restricted component may include a binding molecule, such as a receptor or an enzyme that is specific for the tissue constituent of interest. One such molecule may include carbonic anhydrase. Binding of the tissue constituent to its receptor may affect a downstream response that may result in a change in the electrical properties of a quantum-restricted component.
- The exemplary sensors, described here generically as a
sensor 10, may be coupled to amonitor 70 that may display the concentration of tissue constituents as shown inFIG. 8 . It should be appreciated that thecable 72 of thesensor 10 may be coupled to themonitor 70 or it may be coupled to a transmission device (not shown) to facilitate wireless transmission between thesensor 10 and themonitor 70. Themonitor 70 may be anysuitable monitor 70, such as those available from Nellcor Puritan Bennett, Inc. Furthermore, to upgrade conventional tissue constituent detection provided by themonitor 70 to provide additional functions, themonitor 70 may be coupled to a multi-parameter patient monitor 74 via a cable 74 connected to a sensor input port or via acable 76 connected to a digital communication port. - While the invention may be susceptible to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and have been described in detail herein. However, it should be understood that the invention is not intended to be limited to the particular forms disclosed. Indeed, the present techniques may not only be applied to measurements of carbon dioxide, but these techniques may also be utilized for the measurement and/or analysis of other tissue and/or blood constituents. Rather, the invention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the following appended claims. It will be appreciated by those working in the art that sensors fabricated using the presently disclosed and claimed techniques may be used in a wide variety of contexts. That is, while the invention has primarily been described in conjunction with the measurement of carbon dioxide concentration in blood, the sensors fabricated using the present method may be used to evaluate any number of sample types in a variety of industries, including fermentation technology, cell culture, and other biotechnology applications.
Claims (31)
1. A system comprising:
at least one gas collection chamber into which a tissue constituent is able to diffuse, wherein the gas collection chamber is adapted to be placed proximate to a tissue;
an efferent conduit adapted to transfer the tissue constituent from the gas collection chamber to at least one sensing component, wherein the sensing component is adapted to provide a signal related to the tissue constituent;
an afferent conduit adapted to transfer the tissue constituent from the sensing component to the gas collection chamber; and
a motive force structure adapted circulate the tissue constituent through the system, wherein the motive force structure is adapted to be operatively connected to at least one of the efferent conduit, the afferent conduit, or the sensing component.
2. The system, as set forth in claim 1 , wherein the tissue constituent comprises carbon dioxide, oxygen, ethanol, or carbon monoxide.
3. The system, as set forth in claim 1 , wherein the tissue constituent comprises a volatile anesthetic agent, a volatile product of metabolism, or a volatile xenobiotic.
4. The system, as set forth in claim 1 , comprising a calibration element adapted to provide at least one signal related to at least one physical characteristic of the gas collection chamber.
5. The system, as set forth in claim 4 , wherein the calibration element comprises a coded resistor or an electrically erasable programmable read-only memory.
6. The system, as set forth in claim 1 , comprising a barrier layer defining at least part of a surface of the gas collection structure, wherein the barrier layer is substantially impermeable to water.
7. The system, as set forth in claim 1 , comprising a barrier layer defining at least part of a surface of the gas collection structure, wherein the barrier layer is selectively permeable to the tissue constituent.
8. The system, as set forth in claim 1 , comprising a water-permeable conduit that is impermeable to the tissue constituent, wherein the water-permeable conduit is adapted to direct water away from gas collection structure.
9. The system, as set forth in claim 1 , wherein the sensing component comprises a non-optical transducer, an optical transducer, a chemical indicator, a spectroscopic transducer, or an electrochemical transducer.
10. The system, as set forth in claim 1 , wherein the gas collection structure comprises a tube, wherein at least a portion of the tube adapted to be placed proximate to the tissue is permeable to the tissue constituent.
11. The system, as set forth in claim 1 , wherein the sensing component comprises a calibration element adapted to provide a signal related to the calibration characteristics of the sensing component.
12. The system, as set forth in claim 1 , wherein the motive force structure comprises a pump, a one-way valve, a kinetic motion structure, or a piezoelectrically powered structure.
13. The system, as set forth in claim 1 , comprising an agent adapted to be placed proximate to the tissue, wherein the agent is adapted to increase blood flow to the tissue or wherein the agent is adapted to increase the tissue's permeability to the tissue constituent.
14. The system, as set forth in claim 13 , wherein the agent comprises an electrical heating element, a chemical heating element, nicotinic acid, or salicylic acid.
15. A monitoring device comprising:
a monitor; and
a system adapted to be coupled to the monitor, the system comprising:
at least one gas collection structure adapted to be placed proximate to a tissue; and
an efferent conduit adapted to transfer gas from the gas collection structure to a sensing component, wherein the sensing component is adapted to provide a signal related to a tissue constituent; and
an afferent conduit adapted to transfer gas from the sensing component to the gas collection structure.
16. The monitoring device, as set forth in claim 15 , wherein the tissue constituent comprises carbon dioxide, oxygen, ethanol, or carbon monoxide.
17. The monitoring device, as set forth in claim 15 , wherein the tissue constituent comprises a volatile anesthetic agent, a volatile product of metabolism, or a volatile xenobiotic.
18. The monitoring device, as set forth in claim 15 , comprising a calibration element adapted to provide at least one signal related to at least one physical characteristic of the gas collection chamber.
19. The monitoring device, as set forth in claim 18 , wherein the calibration element comprises a coded resistor or an electrically erasable programmable read-only memory.
20. The monitoring device, as set forth in claim 15 , comprising a barrier layer defining at least part of a surface of the gas collection structure, wherein the barrier layer is substantially impermeable to water.
21. The monitoring device, as set forth in claim 15 , comprising a barrier layer defining at least part of a surface of the gas collection structure, wherein the barrier layer is selectively permeable to the tissue constituent.
22. The monitoring device, as set forth in claim 15 , comprising a water-permeable conduit that is impermeable to the tissue constituent, wherein the water-permeable conduit is adapted to direct water away from gas collection structure.
23. The monitoring device, as set forth in claim 15 , wherein the sensing component comprises a non-optical transducer, an optical transducer, a chemical indicator, a spectroscopic transducer, or an electrochemical transducer.
24. The monitoring device, as set forth in claim 15 , wherein the gas collection structure comprises a tube, wherein at least a portion of the tube adapted to be placed proximate to the tissue is permeable to the tissue constituent.
25. The monitoring device, as set forth in claim 15 , wherein the sensing component comprises a calibration element adapted to provide a signal related to the calibration characteristics of the sensing component.
26. The monitoring device, as set forth in claim 15 , wherein the motive force structure comprises a pump, a one-way valve, a kinetic motion structure, or a piezoelectrically powered structure.
27. The monitoring device, as set forth in claim 15 , comprising an agent adapted to be placed proximate to the tissue, wherein the agent is adapted to increase blood flow to the tissue or wherein the agent is adapted to increase the tissue's permeability to the tissue constituent.
28. The monitoring device, as set forth in claim 27 , wherein the agent comprises an electrical heating element, a chemical heating element, nicotinic acid, or salicylic acid.
29. The monitoring device, as set forth in claim 15 , comprising a multi-parameter monitor.
30. A method comprising:
transferring a tissue constituent in a gas collection chamber to at least one sensing component not located in the gas collection chamber, wherein the sensing component is adapted to provide a signal related to the tissue constituent.
31. The method, as set forth in claim 30 , comprising contacting the tissue constituent with a barrier layer defining at least part of a surface of the gas collection structure, wherein the barrier layer is substantially impermeable to water.
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US11/441,583 US20070106134A1 (en) | 2005-11-10 | 2006-05-26 | Medical sensor and technique for using the same |
US11/479,815 US20070106168A1 (en) | 2005-11-10 | 2006-06-30 | Medical sensor and technique for using the same |
US12/389,746 US7811276B2 (en) | 2005-11-10 | 2009-02-20 | Medical sensor and technique for using the same |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US73562105P | 2005-11-10 | 2005-11-10 | |
US11/441,583 US20070106134A1 (en) | 2005-11-10 | 2006-05-26 | Medical sensor and technique for using the same |
Related Child Applications (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US11/479,815 Continuation US20070106168A1 (en) | 2005-11-10 | 2006-06-30 | Medical sensor and technique for using the same |
US12/389,746 Continuation US7811276B2 (en) | 2005-11-10 | 2009-02-20 | Medical sensor and technique for using the same |
Publications (1)
Publication Number | Publication Date |
---|---|
US20070106134A1 true US20070106134A1 (en) | 2007-05-10 |
Family
ID=38004717
Family Applications (3)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US11/441,583 Abandoned US20070106134A1 (en) | 2005-11-10 | 2006-05-26 | Medical sensor and technique for using the same |
US11/479,815 Abandoned US20070106168A1 (en) | 2005-11-10 | 2006-06-30 | Medical sensor and technique for using the same |
US12/389,746 Active US7811276B2 (en) | 2005-11-10 | 2009-02-20 | Medical sensor and technique for using the same |
Family Applications After (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US11/479,815 Abandoned US20070106168A1 (en) | 2005-11-10 | 2006-06-30 | Medical sensor and technique for using the same |
US12/389,746 Active US7811276B2 (en) | 2005-11-10 | 2009-02-20 | Medical sensor and technique for using the same |
Country Status (1)
Country | Link |
---|---|
US (3) | US20070106134A1 (en) |
Cited By (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2011027182A1 (en) * | 2009-09-01 | 2011-03-10 | Domokos Boda | Tonometric device for examining respiratory insufficiency and regional tissue perfusion failure |
US20120017999A1 (en) * | 2008-12-05 | 2012-01-26 | Fluisense Aps | body fluid sampling device and a method thereof |
WO2014143083A1 (en) * | 2012-04-11 | 2014-09-18 | Exostat Medical, Inc. | Carbon dioxide gas measurement system and method |
US8852095B2 (en) | 2011-10-27 | 2014-10-07 | Covidien Lp | Headband for use with medical sensor |
US9138181B2 (en) | 2011-12-16 | 2015-09-22 | Covidien Lp | Medical sensor for use with headband |
WO2018098510A1 (en) * | 2016-11-30 | 2018-06-07 | Peter Hagl | Multilayer sensor arrangement for determining a substance content in an object being measured, in particular a body part |
US11033670B2 (en) * | 2010-07-07 | 2021-06-15 | Deka Products Limited Partnership | Medical treatment system and methods using a plurality of fluid lines |
US11197951B2 (en) | 2009-10-30 | 2021-12-14 | Deka Products Limited Partnership | Apparatus and method for detecting disconnection of an intravascular access device |
Families Citing this family (18)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US8369920B2 (en) * | 2004-03-09 | 2013-02-05 | Institute Of Critical Care Medicine | Mucosal sensor adaptor |
US20110009762A1 (en) * | 2007-03-08 | 2011-01-13 | FILT Lungen-und Thoraxdiagnostik GmbH | Portable pneumotachograph for measuring components of an expiration volume and method therefor |
US8366630B2 (en) * | 2008-05-29 | 2013-02-05 | Technion Research And Development Foundation Ltd. | Carbon nanotube structures in sensor apparatuses for analyzing biomarkers in breath samples |
WO2010005343A2 (en) * | 2008-07-08 | 2010-01-14 | Marat Vadimovich Evtukhov | Rebreather respiratory loop failure detector |
US8481324B2 (en) | 2008-12-04 | 2013-07-09 | Technion Research And Development Foundation Ltd. | Apparatus and methods for diagnosing renal disorders |
US20110030680A1 (en) * | 2009-07-30 | 2011-02-10 | Nellcor Puritan Bennett Llc | Tracheal tube with drug delivery device and method of using the same |
US9538944B2 (en) * | 2010-09-30 | 2017-01-10 | University Of Maryland Baltimore County | Non-invasive analyte sensing system and method |
CN102812771B (en) * | 2010-10-19 | 2017-04-12 | 华为技术有限公司 | Serving Gateway For Handling Communications Of Mobile Terminal |
WO2013070545A1 (en) * | 2011-11-07 | 2013-05-16 | Landy Toth | Metabolic and cardiopulmonary monitor |
WO2013081956A1 (en) * | 2011-11-29 | 2013-06-06 | U.S. Department Of Veterans Affairs | Method and pulse oximeter apparatus using chemical heating |
TW201325548A (en) * | 2011-12-30 | 2013-07-01 | Chih-Liang Wu | Biometric information sensing device |
US9689826B2 (en) | 2012-03-11 | 2017-06-27 | Technion Research And Development Foundation Ltd. | Detection of chronic kidney disease and disease progression |
US9170193B2 (en) | 2013-06-06 | 2015-10-27 | General Electric Company | Detecting coolant leaks in turbine generators |
US20150093775A1 (en) * | 2013-07-08 | 2015-04-02 | Govind Rao | System and method for analyte sensing and monitoring |
US9097657B2 (en) | 2013-07-23 | 2015-08-04 | General Electric Company | Leak detection of stator liquid cooling system |
EP3242596B1 (en) | 2015-01-09 | 2023-03-01 | Exhalix LLC | Method for analyzing transdermally emitted gases |
SE545316C2 (en) * | 2019-07-05 | 2023-07-04 | Fourth State Systems Ab | Sampling unit, system and method for transcutaneous blood gas monitoring |
US11554237B2 (en) * | 2020-06-17 | 2023-01-17 | Affirm Medical Technologies Ii, Llc | Universal respiratory detector |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4005700A (en) * | 1974-04-05 | 1977-02-01 | G. D. Searle & Co. Limited | Device for measuring blood gases |
US5743259A (en) * | 1995-02-16 | 1998-04-28 | Wayne State University | Apparatus and method for continuous monitoring of tissue carbon dioxide and pH using capnometric recirculating gas tonometry |
US7066884B2 (en) * | 1998-01-08 | 2006-06-27 | Sontra Medical, Inc. | System, method, and device for non-invasive body fluid sampling and analysis |
Family Cites Families (126)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2136236A (en) | 1938-11-08 | B draper | ||
US2638096A (en) | 1949-11-08 | 1953-05-12 | Edith A Waldhaus | Apparatus for oral anesthesia |
US2880072A (en) | 1955-08-12 | 1959-03-31 | Drager Otto H | Method of determining carbon dioxide in gases |
US2890177A (en) | 1956-12-26 | 1959-06-09 | Air Reduction | Carbon dioxide indicator |
US2904033A (en) | 1957-03-04 | 1959-09-15 | Sylvan M Shane | Breathing indicator |
US3067015A (en) | 1960-01-29 | 1962-12-04 | Ray F Lawdermilt | Spoilage indicator for food containers |
US3068073A (en) | 1960-04-22 | 1962-12-11 | Mine Safety Appliances Co | Determination of carbon dioxide |
US3114610A (en) | 1961-05-17 | 1963-12-17 | Martin Marietta Corp | Continuous sampling gas analyzer |
US3238020A (en) | 1961-07-26 | 1966-03-01 | Du Pont | Acid-base test materials |
US3113842A (en) | 1961-10-20 | 1963-12-10 | Corning Glass Works | Gas detection apparatus |
DE6600376U (en) | 1964-06-15 | 1969-01-23 | Asmund S Laerdal | ELASTIC BAG FOR AIR OR OXYGEN SUPPLY IN RESEARCH DEVICES |
DE1972590U (en) | 1964-06-15 | 1967-11-16 | Asmund S Laerdal | VALVE FOR REVIVAL APPARATUS. |
DE1218760B (en) | 1964-08-04 | 1966-06-08 | Auergesellschaft Gmbh | Reagent holder for test tube |
US3373735A (en) | 1965-10-21 | 1968-03-19 | John P. Gallagher | Medical-surgical tube |
US3420635A (en) | 1966-03-28 | 1969-01-07 | Aseptic Thermo Indicator Co | Fruit ripeness telltale |
US3507623A (en) | 1968-04-02 | 1970-04-21 | Mine Safety Appliances Co | Article for the determination of carbon monoxide |
US3505022A (en) | 1969-05-05 | 1970-04-07 | Manley J Luckey | Method and apparatus for determining intoxication |
US3659586A (en) * | 1969-05-20 | 1972-05-02 | Univ Johns Hopkins | Percutaneous carbon dioxide sensor and process for measuring pulmonary efficiency |
US3615233A (en) | 1969-07-28 | 1971-10-26 | Chemetron Corp | Disposable carbon dioxide absorber |
US3612048A (en) | 1970-02-19 | 1971-10-12 | Kentaro Takaoka | Rebreathing apparatus for anesthesia |
US3694164A (en) * | 1970-12-11 | 1972-09-26 | Bjorksten Research Lab Inc | Carbon dioxide sensors |
US3754867A (en) * | 1970-12-11 | 1973-08-28 | Bjorksten Res Lab Inc | Carbon dioxide sensing system |
US3830630A (en) * | 1972-06-21 | 1974-08-20 | Triangle Environment Corp | Apparatus and method for alcoholic breath and other gas analysis |
US4077404A (en) * | 1975-09-17 | 1978-03-07 | H. B. W. Medical Instruments Manufacturing Company, Inc. | Breathing equipment such as resuscitators |
US4003709A (en) * | 1975-10-02 | 1977-01-18 | Visual Spoilage Indicator Company | Visual spoilage indicator for food containers |
US4019862A (en) * | 1976-06-23 | 1977-04-26 | Corning Glass Works | CO2 measurement and reagents therefor |
US4106502A (en) * | 1976-11-18 | 1978-08-15 | Margaret M. Laurence | Resuscitator |
CA1095819A (en) * | 1977-01-14 | 1981-02-17 | Eastman Kodak Company | Element for analysis of liquids |
NL184440C (en) | 1978-05-17 | 1989-07-17 | Battelle Memorial Institute | TEST SAMPLE FOR ANALYZING Dissolved Substances. |
US4287153A (en) * | 1978-09-20 | 1981-09-01 | Towsend Marvin S | Disposable article with non-leachable saline water indicator |
SE7909553L (en) * | 1979-03-19 | 1980-09-20 | Draegerwerk Ag | PROCEDURE AND DEVICE FOR DETERMINATION OF THE ALCOHOLIC CONTENT IN THE EXHAUST AIR |
US4366821A (en) * | 1980-09-15 | 1983-01-04 | Marie C. Kercheval | Breath monitor device |
US4346584A (en) | 1980-10-20 | 1982-08-31 | Boehringer John R | Gas analyzer |
US4389372A (en) | 1981-07-13 | 1983-06-21 | Lalin Hill S | Portable holder assembly for gas detection tube |
JPS5877661A (en) | 1981-11-02 | 1983-05-11 | Fuji Photo Film Co Ltd | Monolithic multilayered analyzing material for analysis of ammonia or ammonia forming substrate and detecting method for said substrate |
JPS5899752A (en) | 1981-11-04 | 1983-06-14 | Konishiroku Photo Ind Co Ltd | Multi-layer analysis element |
US4557900A (en) | 1982-09-28 | 1985-12-10 | Cardiovascular Devices, Inc. | Optical sensor with beads |
US4774941A (en) | 1983-05-04 | 1988-10-04 | Intertech Resources Inc. | Resuscitator bag |
DE3434822A1 (en) | 1984-09-22 | 1986-04-03 | Bayer Ag, 5090 Leverkusen | MEMBRANE FOR REAGENT CARRIER LAYERS, METHOD FOR THE PRODUCTION THEREOF, AND THEIR USE IN ANALYTICAL AGENTS AND ANALYZING METHOD |
DE3540526A1 (en) | 1985-11-15 | 1987-05-27 | Bayer Ag | TRANSPARENT TEST STRIP SYSTEM |
DE3600950A1 (en) | 1986-01-15 | 1987-07-16 | Bayer Ag | 5-ACYLAMIDO-1-ARYL-PYRAZOLE |
JPH0647010B2 (en) | 1986-03-26 | 1994-06-22 | ボ−ド・オブ・リ−ジエンツ、ザ・ユニバ−シテイ−・オブ・テキサス・システム | Endotracheal device |
US4890619A (en) | 1986-04-15 | 1990-01-02 | Hatschek Rudolf A | System for the measurement of the content of a gas in blood, in particular the oxygen saturation of blood |
US4798738A (en) | 1986-10-10 | 1989-01-17 | Cardiovascular Devices, Inc. | Micro sensor |
US4691701A (en) | 1986-07-28 | 1987-09-08 | Tudor Williams R | Carbon dioxide detector |
US4728499A (en) | 1986-08-13 | 1988-03-01 | Fehder Carl G | Carbon dioxide indicator device |
US4994117A (en) | 1986-08-13 | 1991-02-19 | Fehder Carl G | Quantitative carbon dioxide detector |
US5179002A (en) | 1986-08-13 | 1993-01-12 | Nellcor Incorporated | Apparatus for determining whether respiratory gas is present in a gaseous sample |
US5166075A (en) | 1986-08-13 | 1992-11-24 | Nellcor Incorporated | Method for determining whether respiratory gas is present in a gaseous sample |
US4788153A (en) | 1986-10-14 | 1988-11-29 | Eastman Kodak Company | Method for the determination of bilirubin and an element useful therein |
US4832034A (en) * | 1987-04-09 | 1989-05-23 | Pizziconi Vincent B | Method and apparatus for withdrawing, collecting and biosensing chemical constituents from complex fluids |
US4790327A (en) | 1987-07-27 | 1988-12-13 | George Despotis | Endotracheal intubation device |
US4805623A (en) | 1987-09-04 | 1989-02-21 | Vander Corporation | Spectrophotometric method for quantitatively determining the concentration of a dilute component in a light- or other radiation-scattering environment |
SE459126B (en) | 1987-09-15 | 1989-06-05 | Gambro Engstrom Ab | OPTICAL GAS ANALYZER |
US5197464A (en) | 1988-02-26 | 1993-03-30 | Babb Albert L | Carbon dioxide detection |
US5005572A (en) | 1988-02-26 | 1991-04-09 | Brigham & Women's Hospital | CO2 indicator and the use thereof to evaluate placement of tracheal tubes |
US4945918A (en) | 1988-05-04 | 1990-08-07 | Abernathy Charles M | Method and apparatus for monitoring a patient's circulatory status |
US5361758A (en) | 1988-06-09 | 1994-11-08 | Cme Telemetrix Inc. | Method and device for measuring concentration levels of blood constituents non-invasively |
US5124129A (en) | 1988-07-29 | 1992-06-23 | Mallinckrodt Medical, Inc. | Carbon dioxide indicator |
US4928687A (en) | 1988-10-11 | 1990-05-29 | The University Of Florida | CO2 diagnostic monitor |
US5156159A (en) | 1988-10-11 | 1992-10-20 | University Of Florida | CO2 diagnostic monitor with rupturable container |
GB8922049D0 (en) | 1989-09-29 | 1989-11-15 | Medical Instrumentation Consul | Carbon dioxide monitor |
DE69123774D1 (en) | 1990-04-12 | 1997-02-06 | Hitachi Ltd | Device for determining at least one gaseous component in a gaseous or liquid sample and determination method |
US5846836A (en) | 1990-06-06 | 1998-12-08 | Southwest Research Institute | Reversible detector for gaseous carbon dioxide |
US6677159B1 (en) | 1990-06-06 | 2004-01-13 | Southwest Research Institute | Reversible detector for gaseous carbon dioxide |
CA2052711A1 (en) | 1990-10-15 | 1992-04-16 | Alan Nelson | Method of stabilizing a carbon dioxide sensor |
US5109840A (en) | 1991-02-14 | 1992-05-05 | Specialty Packaging Licensing Company | Resuscitator having directional control valve with internal "PEEP" adjustment valve |
MX9702434A (en) | 1991-03-07 | 1998-05-31 | Masimo Corp | Signal processing apparatus. |
DE69227545T2 (en) | 1991-07-12 | 1999-04-29 | Mark R Robinson | Oximeter for the reliable clinical determination of blood oxygen saturation in a fetus |
JPH05119015A (en) | 1991-08-14 | 1993-05-14 | Yamatake Honeywell Co Ltd | Carbon dioxide gas detection element |
US5279289A (en) | 1991-10-15 | 1994-01-18 | Kirk Gilbert M | Resuscitator regulator with carbon dioxide detector |
US6123075A (en) | 1991-10-15 | 2000-09-26 | Mallinckrodt, Inc. | Resuscitator regulator with carbon dioxide detector |
US5204922A (en) | 1991-10-22 | 1993-04-20 | Puritan-Bennett Corporation | Optical signal channel selector |
GB9200431D0 (en) | 1992-01-09 | 1992-02-26 | Abbey Biosystems Ltd | Carbon dioxide detector |
SE505709C2 (en) | 1992-06-29 | 1997-09-29 | Minco Ab | Device for indicating the presence of carbon dioxide in a patient's exhaled air |
US5375592A (en) | 1993-04-08 | 1994-12-27 | Kirk; Gilbert M. | Carbon dioxide detector and shield |
EP1491135A3 (en) | 1993-04-12 | 2005-09-07 | Hema Metrics, Inc. | Method and apparatus for monitoring blood constituents |
US5498658A (en) | 1994-11-17 | 1996-03-12 | The B. F. Goodrich Company | Formaldehyde-free latex for use as a binder or coating |
GB9426053D0 (en) | 1994-12-19 | 1995-02-22 | Trigon Ind Ltd | A carbon dioxide sensitive material |
US5634426A (en) | 1995-02-22 | 1997-06-03 | Tomlinson; Bruce | Absorption depletion indicators for anesthetic gas administration systems |
US6055447A (en) | 1995-07-06 | 2000-04-25 | Institute Of Critical Care Medicine | Patient CO2 Measurement |
US6216024B1 (en) | 1995-07-06 | 2001-04-10 | Institute Of Critical Care Medicine | Method and device for assessing perfusion failure in a patient |
US5714121A (en) | 1995-09-28 | 1998-02-03 | Optical Sensors Incorporated | Optical carbon dioxide sensor, and associated methods of manufacture |
US6058933A (en) | 1996-10-10 | 2000-05-09 | Nellcor Puritan Bennett Incorporated | Resuscitator bag exhaust port with CO2 indicator |
US5749358A (en) | 1996-10-10 | 1998-05-12 | Nellcor Puritan Bennett Incorporated | Resuscitator bag exhaust port with CO2 indicator |
SE9604519D0 (en) | 1996-12-09 | 1996-12-09 | Noster System Ab | Device for capturing and determining carbon dioxide and methods for its use |
US5783110A (en) | 1997-04-17 | 1998-07-21 | R-Tect, Inc. | Composition for the detection of electrophilic gases and methods of use thereof |
US6199550B1 (en) | 1998-08-14 | 2001-03-13 | Bioasyst, L.L.C. | Integrated physiologic sensor system |
GB9819089D0 (en) | 1998-09-02 | 1998-10-28 | Smiths Industries Plc | Respiration assemblies and indicators |
US6319723B1 (en) | 1998-11-12 | 2001-11-20 | Eldon L. Jeffers | Parts per trillion detector |
JP2000206035A (en) | 1999-01-19 | 2000-07-28 | Anritsu Corp | Gas detecting apparatus |
SE9900180L (en) | 1999-01-21 | 2000-02-21 | Mincor Ab | Colorimetric carbon dioxide indicator device |
IL129790A0 (en) | 1999-03-09 | 2000-02-29 | Orsense Ltd | A device for enhancement of blood-related signals |
IE20000226A1 (en) | 1999-03-23 | 2000-10-18 | Analytical Developments Ltd | A method and apparatus for the analysis of a liquid carrying a suspension of organic matter. |
CA2290083A1 (en) | 1999-11-19 | 2001-05-19 | Linde Medical Sensors Ag. | Device for the combined measurement of the arterial oxygen saturation and the transcutaneous co2 partial pressure of an ear lobe |
CA2393393C (en) | 1999-12-15 | 2008-03-18 | Toppan Printing Co., Ltd. | Ink composition for sensing carbon dioxide gas, and carbon dioxide indicator using the same, and package provided with the carbon dioxide indicator |
US20030199095A1 (en) | 2001-06-14 | 2003-10-23 | Kohei Yuyama | Ink composition for sensing carbon dioxside gas, carbon dioxside indicator using the same, package provided with the carbon dioxside indicator, and method for sensing pinhole using the same |
US6816266B2 (en) | 2000-02-08 | 2004-11-09 | Deepak Varshneya | Fiber optic interferometric vital sign monitor for use in magnetic resonance imaging, confined care facilities and in-hospital |
US6428748B1 (en) | 2001-01-31 | 2002-08-06 | Grouptek, Inc. | Apparatus and method of monitoring an analyte |
JP4028760B2 (en) | 2001-06-14 | 2007-12-26 | 株式会社大塚製薬工場 | CO2 gas detection ink composition, carbon dioxide indicator using the same, package with carbon dioxide indicator disposed therein, and pinhole detection method using the same |
US6802812B1 (en) | 2001-07-27 | 2004-10-12 | Nostix Llc | Noninvasive optical sensor for measuring near infrared light absorbing analytes |
US6502573B1 (en) | 2001-11-15 | 2003-01-07 | Mercury Enterprises, Inc. | Portable single patient use carbon dioxide detector |
US6989246B2 (en) | 2002-01-10 | 2006-01-24 | Becton, Dickinson And Company | Sensor formulation for simultaneously monitoring at least two components of a gas composition |
US8996090B2 (en) | 2002-06-03 | 2015-03-31 | Exostat Medical, Inc. | Noninvasive detection of a physiologic parameter within a body tissue of a patient |
US6909912B2 (en) | 2002-06-20 | 2005-06-21 | University Of Florida | Non-invasive perfusion monitor and system, specially configured oximeter probes, methods of using same, and covers for probes |
US7024235B2 (en) | 2002-06-20 | 2006-04-04 | University Of Florida Research Foundation, Inc. | Specially configured nasal pulse oximeter/photoplethysmography probes, and combined nasal probe/cannula, selectively with sampler for capnography, and covering sleeves for same |
US7246622B2 (en) | 2002-10-08 | 2007-07-24 | Vital Signs, Inc. | Carbon dioxide indicating apparatus, particularly, disk-like carbon dioxide indicating apparatus |
USD478522S1 (en) | 2002-10-08 | 2003-08-19 | Vital Signs, Inc. | Carbon dioxide indicator |
US6929008B2 (en) | 2002-10-08 | 2005-08-16 | Vital Signs, Inc. | Carbon dioxide indicating apparatus, particularly, disk-like carbon dioxide indicating apparatus |
JP2004177247A (en) | 2002-11-27 | 2004-06-24 | Oita Univ | Method of measuring carbon dioxide |
US6709403B1 (en) | 2003-01-07 | 2004-03-23 | Mercury Enterprises, Inc. | Manometer CO2 detector combination |
JP4160838B2 (en) | 2003-02-17 | 2008-10-08 | 株式会社日立製作所 | Biological light measurement device |
IE20030144A1 (en) | 2003-02-28 | 2004-09-08 | Univ Dublin City | Improved optical sensors |
JP2005054048A (en) | 2003-08-04 | 2005-03-03 | Toppan Printing Co Ltd | Ink composition for detecting carbon dioxide, carbon dioxide indicator using the same, and package disposed with the carbon dioxide indicator |
GB0319743D0 (en) | 2003-08-22 | 2003-09-24 | Smiths Group Plc | Resuscitators, parts and assemblies |
US20050049468A1 (en) | 2003-09-03 | 2005-03-03 | Sven-Erik Carlson | Increasing the performance of an optical pulsoximeter |
US20050059869A1 (en) | 2003-09-15 | 2005-03-17 | John Scharf | Physiological monitoring system and improved sensor device |
US20050113704A1 (en) | 2003-11-26 | 2005-05-26 | Lawson Corey J. | Patient monitoring system that incorporates memory into patient parameter cables |
US7440788B2 (en) | 2004-08-26 | 2008-10-21 | Kelvyn Enterprises, Inc. | Oral health measurement clamping probe, system, and method |
US7341560B2 (en) | 2004-10-05 | 2008-03-11 | Rader, Fishman & Grauer Pllc | Apparatuses and methods for non-invasively monitoring blood parameters |
US20080262328A1 (en) | 2005-01-21 | 2008-10-23 | Medrad, Inc. | Pulse Oximetry Grip Sensor and Method of Making Same |
US7392074B2 (en) | 2005-01-21 | 2008-06-24 | Nonin Medical, Inc. | Sensor system with memory and method of using same |
WO2006124696A1 (en) | 2005-05-13 | 2006-11-23 | Children's Hospital Medical Center | Multi-wavelength spatial domain near infrared oximeter to detect cerebral hypoxia-ischemia |
WO2007013054A1 (en) | 2005-07-28 | 2007-02-01 | Boris Schwartz | Ear-mounted biosensor |
CA2824033A1 (en) | 2005-09-13 | 2007-03-22 | Edwards Lifesciences Corporation | Continuous spectroscopic measurement of total hemoglobin |
US8233954B2 (en) | 2005-09-30 | 2012-07-31 | Nellcor Puritan Bennett Llc | Mucosal sensor for the assessment of tissue and blood constituents and technique for using the same |
-
2006
- 2006-05-26 US US11/441,583 patent/US20070106134A1/en not_active Abandoned
- 2006-06-30 US US11/479,815 patent/US20070106168A1/en not_active Abandoned
-
2009
- 2009-02-20 US US12/389,746 patent/US7811276B2/en active Active
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4005700A (en) * | 1974-04-05 | 1977-02-01 | G. D. Searle & Co. Limited | Device for measuring blood gases |
US5743259A (en) * | 1995-02-16 | 1998-04-28 | Wayne State University | Apparatus and method for continuous monitoring of tissue carbon dioxide and pH using capnometric recirculating gas tonometry |
US7066884B2 (en) * | 1998-01-08 | 2006-06-27 | Sontra Medical, Inc. | System, method, and device for non-invasive body fluid sampling and analysis |
Cited By (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20120017999A1 (en) * | 2008-12-05 | 2012-01-26 | Fluisense Aps | body fluid sampling device and a method thereof |
US10286149B2 (en) * | 2008-12-05 | 2019-05-14 | Fluisense Aps | Body fluid sampling device and a method thereof |
WO2011027182A1 (en) * | 2009-09-01 | 2011-03-10 | Domokos Boda | Tonometric device for examining respiratory insufficiency and regional tissue perfusion failure |
US20130030272A1 (en) * | 2009-09-01 | 2013-01-31 | Domokos Boda | Tonometric device for examining respiratory insufficiency and regional tissue perfusion failure |
US11197951B2 (en) | 2009-10-30 | 2021-12-14 | Deka Products Limited Partnership | Apparatus and method for detecting disconnection of an intravascular access device |
US11033670B2 (en) * | 2010-07-07 | 2021-06-15 | Deka Products Limited Partnership | Medical treatment system and methods using a plurality of fluid lines |
US11964086B2 (en) | 2010-07-07 | 2024-04-23 | Deka Products Limited Partnership | Medical treatment system and methods using a plurality of fluid lines |
US8852095B2 (en) | 2011-10-27 | 2014-10-07 | Covidien Lp | Headband for use with medical sensor |
US9138181B2 (en) | 2011-12-16 | 2015-09-22 | Covidien Lp | Medical sensor for use with headband |
WO2014143083A1 (en) * | 2012-04-11 | 2014-09-18 | Exostat Medical, Inc. | Carbon dioxide gas measurement system and method |
WO2018098510A1 (en) * | 2016-11-30 | 2018-06-07 | Peter Hagl | Multilayer sensor arrangement for determining a substance content in an object being measured, in particular a body part |
Also Published As
Publication number | Publication date |
---|---|
US7811276B2 (en) | 2010-10-12 |
US20070106168A1 (en) | 2007-05-10 |
US20090156914A1 (en) | 2009-06-18 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US7811276B2 (en) | Medical sensor and technique for using the same | |
US8233954B2 (en) | Mucosal sensor for the assessment of tissue and blood constituents and technique for using the same | |
US8062221B2 (en) | Sensor for tissue gas detection and technique for using the same | |
US7992561B2 (en) | Carbon dioxide-sensing airway products and technique for using the same | |
US20070083094A1 (en) | Medical sensor and technique for using the same | |
US8905029B2 (en) | Airway system with carbon dioxide sensor for determining tracheal cuff inflation and technique for using the same | |
CN106716137B (en) | With the united spectrum and bio-sensor system detected immediately on site | |
US8396524B2 (en) | Medical sensor and technique for using the same | |
EP2945539B1 (en) | Sensor for determining gas concentration | |
US9636058B2 (en) | Sensor for determining concentration of gas | |
JP2005528156A (en) | Apparatus for contacting a tissue surface within a patient's body to measure the patient's physiological parameters and method for measuring the patient's physiological parameters | |
US10732107B2 (en) | Optical sensor, capnography system and methods of use | |
US20040010185A1 (en) | Method for measuring a physiologic parameter using a preferred site | |
TWI334024B (en) | Optical gas density sensor | |
Harsanyi | Chemical Sensors for Biomedical Applications | |
CN209624397U (en) | A kind of analoids | |
US11718865B2 (en) | Methods to improve oxygen delivery to implantable sensors | |
CN109540881A (en) | A kind of analoids |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: NELLCOR PURITAN BENNETT INCORPORATED, CALIFORNIA Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:O'NEIL, MICHAEL P.;SWEDLOW, DAVID B.;REEL/FRAME:017924/0805;SIGNING DATES FROM 20060426 TO 20060508 |
|
STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |