Abstract:
A dual-sensor stethoscope, or retrofit device for a stethoscope, promotes anti-sepsis and stereoscopy through use of a substantially rigid, generally T-shaped tube for support of dual stethoscope heads. Each head may be rotated away from a body independently for use of a single head or rotated into the same general plane for dual-head stereoscopy. A clinician can create a spatial, three-dimensional (3D) anti-septic barrier and avoid the need to carry multiple stethoscopes. During stereoscopy, the use of a common tube allows the transmission of sound with constructive interference of sound waves. The substantially rigid, generally T-shaped support tube allows a clinician to auscultate with one hand and monitor two locations without transference of pathogens.

Description:
BACKGROUND OF THE INVENTION 
   The present invention is drawn generally to a dual-sensor stethoscope that promotes anti-sepsis and stereoscopy. In particular, a stethoscope and retrofit device are disclosed wherein a generally T-shaped tube is used to support dual stethoscope heads that may be rotated away from a body independently. 
   Existing stethoscopes are currently utilized to auscultate or listen to physiologic sounds within the body. Auscultation with existing stethoscopes is currently performed by intermittently applying a stethoscope to the body surface through which the clinician hears various sounds. Intermittent auscultation may be thought of as a relatively benign procedure. However, several disadvantages and hazards are associated with the use of existing stethoscopes. First, patients undergoing surgery may have the sterile field invaded thereby risking infection in order for the clinician to auscultate the chest. To avoid cross-contamination between patients, many clinicians are forced to carry multiple stethoscopes. Additionally, even when a sterile stethoscope is used, it can transfer pathogens from a first location on a patient&#39;s body to a second location during typical auscultation. Furthermore, even in non-surgical environments, transmission of the cold virus is primarily through touch. A clinician&#39;s hand can touch the head of a stethoscope, which then touches a patient and vice versa so as to spread the virus. 
   Another disadvantage of known stethoscopes is that patients are frequently awakened and disturbed so that the clinician may apply a cold stethoscope to the patient&#39;s chest to monitor vital signs. Studies have shown serious developmental abnormalities in newborn infants who are frequently disturbed to auscultate heart and lung sounds with known stethoscopes. Another disadvantage of existing stethoscopes is that the quality of sound wave transmission is dependent upon an airtight seal between the stethoscope and the skin, typically requiring the clinician to touch, and possibly contaminate, the sensor. In the absence of an airtight seal, background noise is inadvertently detected and physiologic sound transmission is impaired. Finally, another disadvantage of existing stethoscopes is that most are not capable of generating positive or constructive interference of physiologic sound waves. 
   Stethoscopes are known which use two sound receiving heads but have several disadvantages. U.S. Pat. No. 4,706,777 to Baumberg discloses a stethoscope with two sound transmitting tubes connected to a valve. Depending upon the position of the valve, the clinician receives either mono or stereo sounds. However, the dual sensor heads require two-handed use and, even when receiving stereo sounds, the sound picked up by each sensor is transmitted through separate channels. As such, it would be desirable to have a dual-sensor stethoscope transmit sound through a common tube with constructive interference of sound waves resulting. 
   Such a dual-head stethoscope with sound transmission through a common tube for constructive interference of sound waves is disclosed in U.S. Pat. No. 4,997,055 to Grady. However, the dual-head arrangement of Grady uses a flexible tubing arrangement that requires use of both hands and requires additional stopcock elements to disable sound transmission from a head that is not in use. 
   U.S. Pat. Nos. 5,650,598 and 5,959,261 to Abelson disclose a dual-head stereophonic stethoscope provided with two conducting tubes and sound sensors, and two 3-way stopcocks. This arrangement enables the sound from one sensor to be conducted to one ear, while that from the second sensor is conducted to the other ear. One of the conducting tubes may be detached when the stethoscope is used for monophonic auscultation. Again, this arrangement lacks any constructive interference of sound waves, and the use of flexible tubing requires use of both hands for dual-head use and significant reconfiguration for single-head use. 
   Other patents disclose stethoscopes with multiple heads. In U.S. Pat. No. 3,124,211 to Cefaly and U.S. Pat. No. 2,722,989 to Tynan, the sound receiving heads are not capable of being used simultaneously. In U.S. Pat. No. 1,853,951 to Zala, U.S. Pat. No. 3,144,091 to Bodenger and U.S. Pat. No. 1,847,607 to Hardt, the sound receiving heads transmit sounds through separate tubes. 
   BRIEF SUMMARY OF THE INVENTION 
   The present invention provides a dual-sensor stethoscope that promotes anti-sepsis and stereoscopy through use of a substantially rigid, generally T-shaped tube for support of dual stethoscope heads. Each head may be rotated away from a body independently for use of a single head or rotated into the same general plane for dual-head stereoscopy. In this manner, a clinician can create a spatial, three-dimensional (3D) anti-septic barrier and avoid the need to carry multiple stethoscopes. When two heads are used for stereoscopy, the use of a common tube allows the transmission of sound with constructive interference of sound waves. In all cases, the substantially rigid, generally T-shaped support tube allows a clinician to auscultate with one hand. The rigid support tube also allows a clinician to obtain a good seal during auscultation without the need to touch any portion of the stethoscope head(s), thus preventing any possible contamination of the head from the clinician&#39;s hand. 
   The simple structure of the rigid, generally T-shaped support tube allows the use of the present invention at low cost and does not require stopcocks or other complex structures. The support tube, and even the sensors (diaphragm and/or bell), can optionally be disposable to further promote anti-sepsis. The support tube can be designed to be retrofitted to any standard stethoscope and use standard stethoscope heads. Use of standard stethoscope heads allows the invention to take advantage of the ordinary ability of a stethoscope head with a bell and diaphragm to be “turned off” by rotation of the head. The structure of the support tube can also provide a means to close the sound transmission path when a sensor is rotated away from a patient. 
   In one embodiment, a stethoscope incorporates a rigid, generally T-shaped support tube for connecting a common sound transporting tube with two rotatable head-supporting tubes. 
   In another embodiment, a rigid, generally T-shaped support tube is disclosed for connection to a common sound transporting tube of a stethoscope at a first end and two stethoscope heads at a second end of a pair of movable rotatable head-supporting tubes. 
   In a further embodiment, a rigid, generally T-shaped support tube is disclosed for retrofitting to a stethoscope for connecting a common sound transporting tube with two rotatable head-supporting tubes. 
   In another embodiment, the rigid, generally T-shaped support tube for retrofitting to a stethoscope for connecting a common sound transporting tube with two rotatable head-supporting tubes is formed of disposable material. 
   In another embodiment, rotatable head-supporting tubes on the rigid, generally T-shaped support tube for a stethoscope include detents or locking means for positioning the rotatable head-supporting tubes in predetermined positions. 
   In yet another embodiment, the rigid, generally T-shaped support tube is adapted for use with pediatric stethoscopes and heads 
   In a further embodiment, the rigid, generally T-shaped support tube is disposable and includes integral disposable heads, diaphragms, and/or bells. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  illustrates an embodiment of a stethoscope in a stereoscopic configuration; 
       FIG. 2  illustrates an embodiment with one head of the stethoscope rotated away to provide a spatial (3D) anti-septic barrier; 
       FIG. 3  illustrates an embodiment utilizing a three-way stopcock; 
       FIG. 4  illustrates an embodiment utilizing a ball pivot; 
       FIG. 5  illustrates an embodiment utilizing a telescoping element; 
       FIG. 6  illustrates an embodiment that has only one rotatable head; and 
       FIG. 7  illustrates an embodiment for single-hand use. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   As used herein, the term head or sensor head refers to a stethoscope sensor and its attachment means that may comprise a diaphragm, a bell, or a combination of the two; the terms rotate and rotatable refer to movement about an actual or virtual pivot point; and the terms tube and tubular refer to any hollow structure for conduction of sound waves and is not limited to circular cross-sections. 
   As illustrated in  FIG. 1 , an embodiment of a stethoscope includes conventional eartips  20  and earpieces  18  connected to common sound conduction tube  16 . In place of a conventional stethoscope head at the end of the tube  16 , a substantially rigid structure is used to mount two sensors  10  to the stethoscope. In use, a clinician can handle the rigid structure to position the sensors  10  and thus avoid contamination of the sensors  10  from any pathogens that may be on the clinician&#39;s hands. In the illustrated configuration of  FIG. 1 , the stethoscope is configured in a position for stereoscopy wherein the stethoscope sensors  10  will transmit sound through common sound conduction tube  16 , which results in constructive interference of sound waves. In an alternate embodiment, as illustrated in  FIG. 3 , a three-way stopcock  13  can be used to select between stereoscopic sensing and sensing from either one or the other sensor head  10 . In this manner, a clinician can selectively listen to two locations on a patient without transferring any pathogens between the two locations. 
   A generally T-shaped support tube includes a first tubular element  14  sized for connecting to common sound conduction tube  16 . When used with conventional stethoscopes, the element  14  will be a tube having the same dimensions as the connection tube of a conventional sensor head. Similarly, when used with pediatric stethoscopes, the element  14  will be a tube having the same dimensions as the connection tube of a pediatric sensor head or can alternately include an adapter element (not shown) to allow connection to a pediatric stethoscope. 
   The T-shaped support tube further includes tube  12  that communicates with element  14  in a central portion and with two rotatable head-supporting tubes  6  at first and second spaced ends of tube  12 . Head-supporting tubes  6 , when used with conventional stethoscope sensors, are dimensioned to allow insertion and connection of conventional sensor heads  10  with bells  8  and/or diaphragms  9 , whether regular and pediatric. Tubes  6  are rotatably attached to tube  12  with rotatable couplings  4  that can be integral or separate from tubes  6 . The rotatable coupling  4  preferably includes or cooperates with a detent or locking means  2  so as to form a substantially rigid support for the sensors  10  that the clinician can grasp and use for obtaining the desired seal or contact of the sensor  10  against the patient. 
   Although the length of tube  12  is illustrated to show a clear distance between the sensor heads  10 , in some embodiments it may be preferable to minimize the length of tube  12  (e.g., only slightly longer than the diameter of each sensor head) in order to allow a clinician to manipulate both sensor heads  10  with a single hand, as illustrated in  FIG. 7 . Additionally, although tubes  6  are illustrated as being identical, the tubes  6  can also have different lengths or have different diameters to allow the use of variously-sized sensors (e.g., a full-sized sensor and a pediatric sensor) on the same stethoscope. Further, an embodiment may comprise only elements  2 ,  4 ,  6 ,  8 ,  9 ,  10 ,  12 , and  14  as a separate unit to retro-fit to existing stethoscopes. 
   As illustrated in  FIG. 2 , which uses identical reference numbers for identical elements, either sensor head  10 ′ may be rotated into another position to create a spatial, 3D anti-septic barrier. Additionally, conventional sensor heads  10 ′ can be “turned off” in the conventional manner by rotation of the diaphragm/bell unit, as illustrated in  FIG. 2 . In certain embodiments, such as low-cost or disposable variations with only a single sensor on each head, the sound conduction can be turned off when a sensor head  10  is rotated away from the patient by a suitable design of the couplings  4 . 
   While there is no overriding need to position the sensor head  10 ′ that has been rotated away in a rigid fashion since the clinician will not be exerting any force on the unused head, it still may be preferable to use a detent or locking means  2  to retain the unused sensor head in a predetermined position away from the patient, such as the illustrated 90° position. While it may be preferable to allow both sensor heads  10  to be rotated, it is also possible to use an embodiment in which only one head  10 ′ is rotatable to another position, as illustrated in  FIG. 6 . 
   The device can be made of any material suitable for use in a medical environment that has the desired mechanical and acoustic properties, including but not limited to stainless steel, silver, silver-plated metals, rubber, silicone, PVC, polypropylene, polyethylene, ABS, SAN, polycarbonate, polystyrene, polyester and combinations thereof. To further the anti-septic function of the device, the materials can also have or be treated to have anti-microbial properties, as is known in the art. 
   In the illustrated embodiments of  FIGS. 1-3 , the longitudinal dimension of the tube  12  determines the separation distance of the sensors  10 . In use, this dimension can be determined based upon the desired separation distance of the sensors for either stereoscopy or alternate auscultation between the two sensors. A clinician can have variously sized devices or tubes  12  to select from, dependant on the desired application, with either the entire T-shaped support or parts thereof being replaceable for different applications. For example, devices for pediatric use will typically be of smaller dimensions. 
   Alternately, various other means can be used for varying the distance between the sensors  10 . As illustrated in  FIG. 4 , one or both (not shown) of couplings  4  can be a multi-directional or ball pivot  4 ′ so as to be able to vary the distance between the sensors. A frictional lock  2 ′ can be used to maintain the position of the sensor  10 . Alternately, a re-positional flexible tube could also be used, but would be more difficult to keep in position. As illustrated in  FIG. 5 , a telescoping element  15  can also be used to vary the distance between the two sensors. 
   As illustrated in  FIG. 6 , an embodiment can employ only a single rotatable head  10 ′ for purposes of simplicity. While illustrated as having a telescoping element  15 , such an element is not required. However, if the telescoping element  15  is integrated with the rotatable coupling  4 , the overlapping portions between tube  12  and element  15  can be used as a bearing for the coupling, with the detent or lock  2 ′ moved to the end of element  15 . While only a single telescoping element  15  is illustrated, multiple elements can be used to further expand the range of the sensor separation distance. 
   As illustrated in  FIGS. 1-6 , typical stethoscope bells, heads or sensors  10  include a rigid extension tube that would ordinarily be inserted into the flexible sound conduction tube  16  of a stethoscope, but in the illustrated embodiments are inserted into tubes  6 , which are dimensioned to accommodate the intended sensor  10 . As such, tubes  6  can be dimensions for the rigid extension tubes of either standard adult or pediatric stethoscope heads.  FIG. 7  illustrates an alternate embodiment in which the rigid extension tube is formed to integrally attach to tube  12 , such as might be done for disposable sensors manufactured for use with in the invention. 
   Embodiments of the invention can be incorporated into a complete dual-head anti-sepsis stethoscope or as a device to convert an ordinary stethoscope into dual-head anti-sepsis stethoscope. Either type of embodiment includes a connection tube dimensioned to engage a sound conduction tube of the stethoscope; a second tube connected to the connection tube, the second tube having a first end and a second end; a first sensor head-supporting tube coupled to the first end of the second tube; and a second sensor head-supporting tube coupled to the second end of the second tube; wherein at least one of the first and second sensor head-supporting tubes is rotatably coupled relative to the second tube. 
   Further embodiments can optionally include various details, including but not limited to one or more of: having both the first and second sensor head-supporting tubes are rotatably coupled relative to the second tube; having a detent or locking means for restraining movement of the at least one sensor head-supporting tube that is rotatably coupled relative to the second tube; having a stethoscope head integrated into each of the first and second sensor head-supporting tubes; having the device or parts thereof constructed from disposable materials; having the second tube further comprise at least one telescoping element; having the second tube connected to the connection tube at a location between the first and second ends; having a three-way stopcock positioned at the location between the first and second ends where the second tube is connected to the connection tube; and having the connection tube directly connected to one of the first and second sensor head-supporting tubes. 
   A device for providing a dual-sensor anti-sepsis stethoscope has been described. It will be understood by those skilled in the art that the present invention may be embodied in other specific forms without departing from the scope of the invention disclosed and that the examples and embodiments described herein are in all respects illustrative and not restrictive. Those skilled in the art of the present invention will recognize that other embodiments using the concepts described herein are also possible. Further, any reference to claim elements in the singular, for example, using the articles “a,” “an,” or “the” is not to be construed as limiting the element to the singular.