Patent Application
20050251119
The subject matter of the present disclosure relates to an apparatus and method of illuminating a stylet for intubating patients.
In some situation, illuminated stylets are useful for intubating patients. For example, illuminated stylets may be used when a patient has a difficult, obstructed or blocked airway, when conventional direct laryngoscopy has failed, or when circumstances do not permit use of laryngoscopy. During use, the illuminated stylet is inserted into an endotracheal tube until the light source at the distal end of the stylet reaches the tip of the tube. The tube and stylet can then be bent at a sharp angle to facilitate insertion into the oral cavity of a patient being intubated with their head in a neutral position. The end of the tube and stylet are then inserted into the patient's mouth, and the tip is advanced over the base of the tongue until a pre-tracheal glow is identified in the patient's neck. The pre-tracheal glow is a red, downward streaking glow seen in the neck of the patient from the lighted tip of the stylet. When the illuminated tip of the stylet is correctly positioned in the glottic opening, a bright red, teardrop shaped glow is illuminated in the anterior of the patient's neck. Identification of this pre-tracheal glow is used to determine proper insertion of the tube and stylet, and those performing the intubation look for characteristics of brightness, shape, and location to determine whether the tip is being properly inserted during the procedure.
Illuminated stylets currently in use have a single light source at the end of the stylet. Once the tip of the stylet passes the larynx, the oral cavity becomes dark, limiting the recognition of foreign objects or potential changes that can occur when the patient is choking, vomiting, or aspirating vomitus. In addition, producing the pretracheal glow requires translumination of the soft tissues in the neck, which may be hard for those performing the procedure to see when there is too much ambient light. Prior art illuminated stylets use white light for illumination. Because of the way the human eye perceives color, the red light portion of the white light is absorbed less so that more is transmitted through the skin and tissue to achieve the pre-tracheal glow due to the red hemoglobin in the blood and tissues. Conversely, the non-red components of the white light are absorbed by the tissues resulting in less light being transmitted completely through the bodies tissues to achieve the pretracheal glow. Furthermore, some prior art illuminated stylets, such as the Surch-lite stylet from Aaron Medical, have incandescent light bulbs on the tip of the stylet. Because of the size of these light bulbs, the stylet may not be suitable for use with endotracheal tubes having small internal diameters.
The subject matter of the present disclosure is directed to overcoming, or at least reducing the effects of, one or more of the problems set forth above.
An illuminated stylet includes an endotracheal tube, one or more light sources and one or more fiber optic elements. In one embodiment, the stylet has a fiber optic bundle positioned inside the tube and emitting red light substantially at a distal end of the tube. In another embodiment, the stylet has a bundle positioned inside the tube and has a scintillating fiber optic positioned outside the tube. The bundle emits light substantially at the distal end of the tube, while the scintillating fiber optic emits light substantially along a length of the fiber optic. The bundle and scintillating fiber optic can have the same light source or can have different light sources. In one embodiment, the bundle has a light source, such as a red laser diode, that generates red light at a wavelength of about 690-nm, while the scintillating fiber optic has a white light emitting diode (“LED”) as its light source.
The foregoing summary, preferred embodiments, and other aspects of the present disclosure will be best understood with reference to a detailed description of specific embodiments, which follows, when read in conjunction with the accompanying drawings, in which:
An apparatus and method to illuminate a malleable stylet are disclosed. The apparatus includes a side-emitting fiber optic system attached to the stylet. Using the apparatus and method, manufacturers can incorporate the side-emitting fiber optic system during the construction of the stylet.
When the light source is activated by push button 22, the light source generates light, and fiber optic bundle 40 conveys the light to a distal end of bundle 40 where the light is emitted substantially at the distal end of tube 30. In one embodiment, the light source generates white light. In an alternative embodiment, the light source generates only red light and preferably red light having a wavelength around approximately 690-nm.
As evidence by the embodiment of
In one embodiment, elements 80 and 90 can share a common light source (not shown) housed in handle 60. In an alternative embodiment, each of elements 80 and 90 can have their own light source (not shown) housed in handle 60. These light sources can generate substantially the same characteristics of light. In yet another embodiment, multi-fiber bundle 80 is illuminated by a light source generating a different color of light than side emitting fiber optic 90, allowing for two different colors of light to be used to optimize visualization. For example, fiber optic bundle 80 can have a first light source that generates only red light, while scintillating fiber optic 90 can have a second light source that generates different light (e.g., white light).
As is known, light striking an object is absorbed, reflected, or transmitted through the object, and human perception of the wavelength of the light is indicated by color. To perceive a color correctly three primary elements must be present: red, green, and blue. The ratio of these primary elements gives a person the indication of the color of an object. The ratio of phosphors in a white LED is approximately one blue (470-nm), one red (690-nm) and two green (550-nm). This gives the perception of a white light. Due to the abundance of hemoglobin in blood, human tissue transmits the green and blue elements of the white light very poorly, yet red is transmitted readily. Thus, red or infrared is the color of choice for pulse oximetry. In a preferred embodiment, fiber optic bundle 80 has a light source generating red light with a wavelength of approximately 690-nm to facilitate pre-tracheal glow through the neck tissue of a patient, and scintillating fiber optic 90 has a light source generating white light. For example, central multi-fiber bundle 80 can have a red laser diode (690-nm) as its light source, and side-emitting fiber optic 90 can have a white LED light source. This color combination can improve visualization and can also efficiently use the battery power.
As shown, push button switch and end cap 62 inserts into the end of handle 60. A set screw or other coupling mechanism 64 inserts into the opposing end of handle 60 and holds the malleable tubing of endotracheal tube 70 of the stylet firmly into handle 60. Fiber optic bundle 80 is inserted into the malleable tubing of tube 70 and is slightly shorter than tube 70. Scintillating fiber optic 90 is positioned adjacent tube 70 along a length of tube 70. In the present embodiment, scintillating fiber optic 90 runs external to the malleable tubing of tube 70 (i.e., on the outside of tube 70) and is slightly shorter than the length of tube 70. In an alternative embodiment, scintillating fiber optic 90 can be inserted within tubing 70 along with fiber optic bundle 80.
As noted in the Background Section, prior art illuminated stylets use a single light source at the end of the stylet. Once the tip or distal end of the stylet passes the larynx, the oral cavity becomes dark, limiting the recognition of foreign objects or physical changes in a dynamic environment, e.g. the patient choking, vomiting, or aspirating vomitus. In contrast, the light emanating from side emitting fiber 90 in accordance with one embodiment of the invention provides better visualization of the oral cavity during the procedure.
Referring to
The disclosed illuminated stylets can be used with additional devices such as, for example, a laryngoscope. The lighting unit may be designed to be disposable with the stylet after a single use or reusable by removing and replacing the malleable tube and fiber optics. All components can be sterilized in situ with other parts of the stylet and endotracheal tube using gas autoclaves, ultraviolet light, or other conventional chemical sterilization techniques. The unit, as described herein, is battery operated and can be activated by a pull-tab for one-time use (i.e., for a disposable stylet) or activated by an on-off switch. For example, the lighting unit also can be designed to be reusable in two ways. In a first way, the malleable tube and fiber optics can be made removable and disposable so that only the handle and lighting unit housed in the handle are reused. In a second way, a disposable plastic sheath (similar to what is used for thermometers) can be used to cover the malleable tube.
The preceding description has been presented to enable any person skilled in the art to make and use the invention as claimed and is provided in the context of the particular examples discussed below, variations of which will be readily apparent to those skilled in the art. Accordingly, the claims appended hereto are not intended to be limited by the disclosed embodiments, but are to be accorded their widest scope consistent with the principles and features disclosed herein.
This application claims the benefit of U.S. Provisional Application Ser. No. 60/569,661 filed May 7, 2004, which is incorporated herein by reference in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 60569661 | May 2004 | US |
