Abstract:
A method and apparatus for facilitating the locating of vessels in a living body, the apparatus having an enclosure for surrounding a portion of the living body, a light source positioned to illuminate the body portion, a sight for viewing into the enclosure, and a secondary light source for illuminating the interior of the enclosure, the method comprising the steps of transilluminating a body portion with a light source.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to the field of medicine, and specifically to an apparatus for locating and viewing subcutaneous vessels. 
     2. Brief Description of the Related Art 
     In the field of medicine, it is common to administer fluids, and to take samples of human blood, by accessing the veins and arteries of patients. The withdrawal of blood with needles and the insertion of catheters are two common procedures which require percutaneous access to veins and arteries of a person. Fluids, such as, for example drugs, proteins and other nutrients are routinely delivered to patients by medical personnel. While some medications can be delivered orally, or intramuscularly, with a syringe and needle, in many cases it is necessary to deliver fluids and drugs directly, intravenously, into the blood stream. To do this, trained medical personnel are required to locate an appropriate vessel, such as a vein or artery, into which the fluids or drugs can be administered. 
     In addition, blood samples are usually obtained through veins. The puncture of a vein with a needle is a preferred way to obtain a patient&#39;s blood sample. Also, catheterization of veins and arteries may take place through insertion of an apparatus into the vessel. 
     While locating and puncturing veins and arteries in adults is routinely done, it is often very difficult to locate veins of certain individuals, such as obese individuals, whose arteries are not as close to the skin surfaces as those of a person of normal weight. It is also difficult for medical personnel to locate and puncture veins and arteries of persons with very low blood pressure, and infants whose arteries are difficult to locate. 
     Human arteries and veins are approximately 2 to 8 millimeters in diameter. In infants, again the problems of locating and puncturing veins and arteries in order to carry out medical procedures can be very difficult or impossible at times. While physicians and other trained medical personnel sometimes have difficulty locating the veins and arteries of a healthy adult human, even more challenging, and sometimes impossible, to locate and puncture the veins and arteries of an infant. Infants, like adults, at times require surgery, administration of treatment, or other medical procedures which mandate the delivery of intravenous fluids into a vessel. Blood sampling also requires access to an infant&#39;s blood vessels. Locating the vein of an infant can be crucial, especially in emergency situations, where it is important to find the veins as rapidly as possible so that any necessary procedures can be carried out. There is a great risk imposed on the infant patient when there is a delay in providing the needed intravenous fluid or drugs. Delay in these cases can be fatal. For example, an infant who is unable to receive a crucial intravenous delivery may dehydrate; or, if a sufficient blood sample cannot be obtained from the infant within the appropriate time frame, it may be impossible to provide the appropriate treatment, or know how much of a medication to administer. 
     In other instances, certain diseases require the intermittent administration of intravenous fluids. For example the treatments of many diseases, such as, major infections, renal disease, and cancer, may include continuous or intermittent intravenous therapy. 
     The most commonly used method for insertion of intravenous delivery devices, such as a catheter, is by percutaneous needle puncture, directly into a vessel. Again, finding the vein or artery is critical to a catheter set up. 
     Presently, knowledge of an infant&#39;s anatomy is essential, and, moreover, is relied upon where the tiny infant veins are not visible. Although one may well know an infant&#39;s anatomy, the location of veins in an infant, while having a generally identifiable location, can vary slightly in each infant. As a result, repeated needle sticks may take place before a successful puncture of the vessel is achieved. This can lead to infections due to the instances of the repeated needle sticks and their tendency to introduce bacteria into the individual. This can occur, even where the medical personnel uses the proper procedures. Therefore, even a commanding knowledge of infant anatomy does not ensure that one will find the infant&#39;s vein on the first attempt, or even at all. 
     When the vein cannot be found, for example, when taking a blood sample, or when inserting an intravenous line, time for treatment administration can be compromised. In these situations, where live-saving treatment must be administered, or a blood sample obtained, it is sometimes necessary to insert a needle or catheter in the bone, such as the tibia. This is very painful to the patient, but, where life-saving treatment or access to the blood is necessary, the bone must be pierced. 
     In order to locate veins, it is a common practice to constrict veins in a desired area to more clearly delineate the veins. Apparatus such as straps and bands have been used for this purpose. U.S. Pat. No. 5,647,850 issued on Jul. 15, 1997 to William Allen discloses a “Method and Apparatus for Vein Location” which uses an inflatable bladder which is disposed about a patient&#39;s limb to constrict the blood flow. 
     While problems locating veins and arteries have been recognized, there have been some known attempts to improve the ability to locate veins within the body. U.S. Pat. No. 3,745,989 issued on Jul. 17, 1973 to Sanford Pinna discloses a “Device for Locating Veins in Living Bodies” which provides a spring-tensioned sensor rod and a marking rod mounted for axial reciprocation to respond to the sensing of a vein to mark its location on the skin. Similarly, U.S. Pat. No. 3,782,365 issues on Jan. 1, 1974 to Sanford Pinna discloses a “Detector for Locating Veins in Living Bodies.” 
     U.S. Pat. No. 3,999,210 provides a “Method of Locating Vein” which employs a temperature sensitive film for aiding in the locating of veins in the arm. The 210 patent utilizes a liquid crystal material which is encapsulated in a film, and is sensitive to temperature to provide color variations corresponding to the location of the veins. 
     Other attempts to locate veins have included ultrasonic devices, such as the “Device for Guiding a Surgical Needle into a Blood Vessel” disclosed in U.S. Pat. No. 4,527,569, issued on Jul. 9, 1985 to Peter Kolb. U.S. Pat. No. 5,309,915 issued on May 10, 1994 to Charles Ember, discloses an “Apparatus for Locating Veins and Arteries” which utilizes ultrasonic signals to locate the vessel and produce an audible tone. A signal processing device utilizing a Doppler type of device is disclosed in U.S. Pat. No. 4,667,679 entitled “Apparatus and Method for Positioning and Puncturing an Artery and a Vein.” The &#39;679 device provides an intermittent visible light or sound alert when the blood vessel is detected. 
     Infrared imaging has been used to obtain an image which is recorded on a video monitor. An example is U.S. Pat. No. 4,817,622 entitled “Infrared Imager for Viewing Subcutaneous Location of Vascular Structures and Method of Use” issued on Apr. 4, 1989 to Carl Pennypacker, et al. The &#39;622 device provides a television camera and monitor for viewing an appendage. Similarly, U.S. Pat. No. 5,519,208 entitled “Infrared Aided Method and Apparatus for Venous Examination” issued on May 21, 1996 to Joel Esparza, et al. uses irradiation of the surface area of a patient to locate veins of the individual. U.S. Pat. No. 5,608,210 also entitled “Infrared Aided Method and Apparatus for Venous Examination” issued on Mar. 4, 1997 to Joel Esparza, et al. discloses a headpiece which is worn by medical personnel when inserting a hypodermic needle into a vein. U.S. Pat. No. 5,678,555 issued on Oct. 21, 1997 to Peter O&#39;Connell for a “Method of Locating and Marking Veins” discloses an infrared imaging camera and a remote viewing screen to locate the veins of a patient. 
     Other attempts to locate veins have involved invasive procedures where locating devices themselves, although provided to reduce trauma which can result from repeated or failed needle sticks, can also cause trauma. In U.S. Pat. 5,167,629 issued on Dec. 1, 1992 to Mathieu Vertenstein, et al., a “Vein Locator” is disclosed which is sutured to subcutaneous tissues at a fixed location relative to the vein. The &#39;629 device utilizes protuberances which can be felt by palpating the patient&#39;s skin to locate the vein. 
     When carrying out procedures such an venapuncture, direct viewing of the vessel is preferred. In a person with readily visible veins, the medical personnel can easily locate the vein and perform the necessary puncture. It is this primary preferred method which is utilized whenever possible. A need exists for a device which will enable the method of directly locating and sighting vessels to be carried out in instances where the vessels are not readily observable, such as those of an infant. 
     A need exists for a better way to carry out the puncture of veins and arteries of infants. Specifically, it is desirable to avoid the consecutive needle sticks, to provide a time-saving, effective way to administer fluids and medicines through an intravenous line, as well as to draw blood for sampling, immediately as needed. 
     SUMMARY OF THE INVENTION 
     An apparatus for locating vessels of a patient in order to carry out medical procedures is provided. The vessels to be located can be veins or arteries. The present invention has particular applicability with respect to infants, whose veins are difficult to locate due to their small size and their location beneath the skin and tissue. The apparatus has a first light source which is positioned below the limb or appendage containing the vessel to be punctured. For example, the arm of an individual, such as an infant, may contain veins which can be punctured with a needle to obtain a blood sample. The first light source is preferably a cold light source which is positionable over a range of locations to maximize the visibility of vessels. Preferably, a support is provided on which the appendage or limb of the patient is positioned. The light source illuminates the limb from below. The light source is provided to have an intensity which can shine through the limb. This transillumination of the limb facilitates the exposure of the vein positions. A frame can be provided to support the limb and the light source. Preferably, an enclosure surrounds the limb area from which the blood sample is to be taken. One or more openings in the device provide access to the enclosed area such as, for example, apertures which can permit the hands of medical personnel to be inserted into the enclosed space in order to carry out the puncture of a vein or artery. Portholes can be provided, or alternately, can be fitted with sleeved gloves if a more sealingly enclosed environment is desired. A sight is provided at the top of the cover so that medical personnel can directly view the appendage. The sight can be provided as an opening, or can have one or more lenses associated therewith for enlarging, enhancing, or correcting the viewing. 
     An opening is provided in the side of the device through which the patient&#39;s arm is inserted so that the desired appendage or area thereof is positioned within the device. Baffles can also surround the arm at the entrance to limit excess light spillage into the device. Furthermore, if necessary, an optional opening at the opposite end can be provided to permit an appendage to pass therethrough, if necessary. The openings can have removable covers. 
     A positionable, secondary light source can be provided to illuminate the surface of the appendage within the device. 
     It is a primary object of the present invention to provide a novel device for locating the blood vessels of a patient, and particularly those patients whose veins are difficult to find, such as an infant. 
     It is another object of the present invention to accomplish the above objects by transilluminating an appendage to facilitate locating a vein or artery. 
     It is another object of the present invention to provide an apparatus which can reduce trauma associated with needle punctures, and which can facilitate the speed with which a vessel can be located and punctured. 
     It is another object of the present invention to provide a portable device which can be carried in the field, and powered by an energy cell or rechargeable power supply. 
    
    
     BRIEF DESCRIPTION OF THE DRAWING FIGURES 
     FIG. 1 is a perspective view of an apparatus for locating vessels in a living body. 
     FIG. 2 is front elevation view of the apparatus of FIG.  1 . 
     FIG. 3 is a front perspective separate view showing the moving means including a track along which the light can be moved. 
     FIG. 4 is a front perspective separate view of an alternate embodiment of the moving means showing a gear arrangement. 
     FIG. 5 is a top perspective sectional view taken through the enclosure. 
     FIG. 6 is a rear elevation view of the apparatus of FIG. 1, shown with the cover partially lifted. 
     FIG. 7 is a front elevation view of an alternate embodiment of an apparatus according to the invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring to FIG. 1, an apparatus  10  constructed in accordance with the present invention is shown comprising an enclosure  11  with an opening  12  therein for accommodating a body portion of a person, such as, for example, an arm  100  of an infant shown in broken-line representation. Sight means for viewing into the enclosure space is provided and is shown comprising a pair of apertures  13 ,  14  on a top wall portion  15  of the enclosure  11 . The enclosure  11  has a first side wall  16 , a second side wall  17 , a front wall  18 , a rear wall  19 , a top wall  21  and a bottom wall  22 . The top wall  21  can be formed from one or more wall portions, such as the first top wall portion  15 , second top wall portion  23  and third top wall portion  24 , with the first top wall portion  15  adjoining with an adjacent edge of the rear wall  19 , and an adjacent edge of each of the second top wall portion  23  and third top wall portion  24 , either directly or indirectly through a hinge or other connecting means. 
     Access means is provided for permitting access into the enclosure  11 . Preferably, the access means can comprise apertures in the enclosure, such as the first and second apertures  30 ,  31  disposed in first and second side walls  16 ,  17 , respectively. The apertures  30 ,  31  permit the medical personnel to insert his or her hands therethrough in order to carry out procedures in the enclosure  11 , such as venapuncture, as discussed herein. The apertures  30 ,  31  can be provided sealed, with sealing means, such as the attached gloves  33 ,  34 . The attached gloves  33 ,  34  can be removably provided to connect with and disconnect with the apparatus  10 , as needed, and may be replaced as needed, in the event they are damaged, stained or contaminated. 
     Window means is provided on the bottom wall  22  for providing an opening to the enclosure  11 . Light source means for supplying light, such as the light source  40  can be mounted below the bottom wall  22  or as shown in a preferred embodiment in FIGS. 1,  2  and  6 , on a side wall  17  of the enclosure  11 , to supply light to the body portion, such as the arm  100 , when it is placed in the enclosure  11 . The light source  40  can be switched with any conventional switching means, such as the switch  49  which comprises a commercially available switch, to permit the medical personnel using the device to turn on the light source  40  as needed. Preferably, moving means is provided to move the light  41  of the light source  40  over a range of positions. The light  41  of the light source  40  is movably provided, and as shown in FIG. 3, can be mounted on a slide means, such as the tracks  45  installed on the underside of the bottom wall  22 , to provide a range of movement for the light  41  along the window means. The window means can comprise a window  39  disposed in the bottom wall  22 . The window  39  can have support means on one or more of its edges for supporting the arm  100  of the body. The support means is shown comprising a foam material  42 . The window  39  may be open or can have a clear cover which permits light to pass therethrough. 
     The apparatus  10  can also include holding means to hold the body portion  100  in place in the enclosure  11  to facilitate carrying out procedures, such as a venapuncture. The holding means can comprise a first strap  44  and a second strap  45 . The straps  44 ,  45  can be provided in two sections, such as the first strap sections  44   a,    45   a,  and second strap sections  44   b,   45   b, the sections  44   a,   44   b  being selectively fastenable to each other to secure an arm  100  on the apparatus  10 , and likewise, the sections  45   a,   45   b  being selectively fastenable to each other. The first strap sections  44   a,    45   a  can comprise on of a surface of hooks and loops, and the respective fastening second strap sections  44   b,   45   b  can comprise the other of a surface of hooks and loops, such as that sold under the trademark VELCRO®. While two straps  44 ,  45  are shown, it is understood that more than two straps can be used for additional holding, or alternately, a single strap can be used. 
     The light source  40  preferably comprises a cold light source, and can be provided in the form of a fiber optic light  41  with a power source  40   b  and a tube  40   c,  which permits cold light to be directed to the body appendage  100 . The light source  40  is provided having an intensity sufficient to permit the light to illuminate the body appendage  100 . For example, the light source  40  can be powered by an external power supply, or any other suitable power source, such as a battery, or energy cell. The use of a rechargeable battery is particularly desirable for field applications, such as emergency medicine, where portability is desired and where electric outlets may not be available. 
     The light source means can comprise any suitable light which has sufficient intensity to illuminate the appendage, the arm  100 . A battery-powered light, such as as incandescent bulb can be provided to comprise the light source. Other lights, such as, for example high intensity light sources which can be electrically or battery powered can be used. In one embodiment, according to the invention, the light source can comprise a low voltage light source, such as that commonly used with flashlight devices, which can be powered by battery cells, a power adapter, or other supply. In the event that a light is used which produces heat, it will be spaced a sufficient distance from the appendage, and limited in duration so that it is not allowed to remain on for an extensive period of time, in order to avoid potential damage to the limb  100  from excessive heat. The window  39 , for example, can be fitted with a panel, such as, for example plexiglass, in order to help dissipate heat from the light source or insulate the appendage against the heat. 
     The transillumination of the arm  100  by the light from the light source means makes the veins of the arm visible when viewing the arm  100  from above, such as, for example with the light from the light source  40  being directed from below the arm  100 . The light transmitted from the light source  40  illuminates the arm  100 , and passes through the arm  100  and is visible to the medical personnel viewing it through the sight means. However, the veins do not permit the same amount of light to pass through as compared with those areas of the arm where there are no veins. The veins, therefore, become observable. Preferably, the light  41  is positioned to illuminate through the arm  100  by positioning the light  41  on the posterior side of the arm  100  and having it illuminate transversely through the arm  100  for viewing of vessels on the anterior side of the arm  100 . When the light transmitted from the light source  40  is passed through the arm  100 , locating the veins is facilitated so that a venapuncture can be carried out. To further facilitate carrying out procedures in the enclosure  11  of the apparatus  10 , a second light source  50 , which can be controlled by a switch  51  is provided to illuminate the working area in the enclosure  11 . The second light source  50  can be switched on after the vein is located, so that once the vein is found a procedure can be carried out without having to relocate the patient, or the patent&#39;s arm  100 . The switch  51  preferably is located near the sight means so that it can be operated with the head of the medical personnel using the device  10 . Alternately, the switch  51  can be remotely located, such as by a foot switch, to enable the medical personnel to control the second light source  50 , even when both hands are being used for other tasks. The switch  51  can also include dimmer circuitry, of the type known in the art and commercially available, for varying the intensity of the light output transmitted by the second light source  50 . The second light source  50  can comprise any light-producing element, such as an incandescent light bulb, connected to a power supply, and for example can be run off of the same power supply  40   b  which powers the light  41  of the first light source  40 . 
     Preferably, the enclosure  11  is provided to block out extraneous light so that light from the first light source  40  remains more concentrated to the observer, and the transillumination effect is more readily observed. The opening  12  in the rear wall  19  can have flaps  20  for sealing the enclosure  11  to further block outside light from spilling into the enclosure  11 . A frame  60  is shown. The light source  40  is preferably supported on the frame  60  or on an enclosure wall. 
     The moving means for moving the position of the light  41  of the light source  40  can be supported on the frame  60  or bottom wall  22  of the enclosure  11 . The moving means can comprise a slide member  61  connected to the light  41  to move the light  41  along the area of the window  39 . The slide member  61  has a handle  62  connected by a rod  63  which can be operated to move the light  41  along the tracks  45  in the directions of arrow “a” to position the light  41 . Alternately, the moving means can, for example, comprise a geared arrangement, where a knob can be used to turn a gear, such as a worm gear which can move the light source in either direction along double arrow “a”. A geared moving means is shown in FIG. 4 comprising a knob  70 , a shaft  71  connected to the knob  70  and having a first gear  72  thereon, and a second gear  73  disposed on the light  41  which meshes with the first gear  72 , such that when the shaft  71  is rotated, the first gear  72  rotates with the shaft  71  and causes the light  41  to move along a slide rod  74  in either direction of arrow “b”. The light  41  preferable is carried by a housing  75  which has a bore  76  through which the housing  75  is slidably mounted on the slide rod  74 . The slide rod  74  preferably is supported on the apparatus  10  with mounting brackets  77 . One or more mounting brackets  78  can secure the shaft  71  to the apparatus  10 . 
     As shown best in FIGS. 1 and 6, a hinged cover  80  can also be provided to facilitate access to the enclosure  11 . The cover  80  is formed by the third top wall portion  24 , the first side wall  16  and a portion  19   b  of the front wall  19 . The hinged cover  80  can further have a lifting handle  81 , and can have gasketing means to assist in blocking extraneous light from entering into the enclosure  11 . The gasketing means is shown comprising a gasket seal  82  which is disposed around the perimeter of the opening between the enclosure  11  and the hinged cover  80  so as to provide a gasket between the edges of the cover  80  and enclosure walls when the cover  80  is closed, as shown in FIG.  1 . The gasket seal  82  can comprise a single element or a plurality of gasketing elements, and, for example can be formed from a rubber strip, or other suitable element. The hinged cover  80  is provided so that it can be lifted to rotate in the direction of double arrow  120  and further rotated to be positioned on the second top wall portion  23  of the enclosure  11  to rest thereon and remain in an open position after being rotated through the arc represented by double arrow  121 . Similarly, the cover  80  can be closed by returning it from its open position to its closed (FIG. 1) position. Lifting is facilitated by the lifting handle  81 . While a single lifting handle  81  is shown, it will be understood that a plurality of lifting handles can be provided, and the configuration of the lifting handle  81  shown comprising a lifting tab, can have alternate configurations which provide suitable ability to lift the cover  80 . The lifting of the cover  80  preferably is done after a successful vein is located and needle stick has been performed. In this manner, the hand of the user which had previously extended through the first apperture  30  on the side wall  16  in order to carry out the procedure, is removed, while the other hand of the user extending through the second apperture  31  on the second side wall  17 , can remain holding the needle in position on the patients appendage  100 . This permits the right hand of the user to gain fall access and more mobility by reaching into the enclosure  11  once the cover  80  has been opened, as shown in FIG.  6 . The cover  80  can be secured with the hinges  83 ,  84  which can attach to the cover surface formed by the third top wall portion  24  and enclosure second top wall portion  23 . In addition, the interior surfaces of the first side wall  16 , second side wall  17 , front wall  19 , rear wall  18 , top wall  21  and bottom wall  22  can be coated or darkened so as to reduce the amount of light which may be reflected from the walls when locating a vessel. 
     Shade means can also be provided to cover the access means or first and second apertures  30 ,  31 , in order to block extraneous light from entering the enclosure  11 . The shade means can comprise a plurality of flaps or baffles  20  which are deflectable when the enclosure  11  is accessed, and which return to a position to block the aperture  30 ,  31  when an individual&#39;s hands are withdrawn from the enclosure  11 . 
     As shown in FIG. 5, support means comprising a supporting material such as a foam or cushion  98  can be disposed around the window  39  to cushion the arm  100 . 
     While the sight means is shown comprising apertures  13 ,  14  for viewing into the enclosure  11 , it will be understood that one or more optical lenses can be provided to enhance the viewing of the body portion  100  and any medical instruments, such as needles or catheters used to carry out a venapuncture. For example, the sight means can further include corrective, and or magnifying lenses, including variable zoom lenses, such as those commercially available, for enhancing the viewing of the instruments and body portion in the enclosure  11 . In an alternate embodiment shown in FIG. 7, the light means comprises a window  213  disposed in a top wall  215  of the enclosure  211 . The device  210  is constructed similar to the invention described above in connection with FIGS. 1-6, and has a light source  240 , means for moving the light, such as, for example the handle  262  and shaft  263 . The remainder of the device  210  is not shown, however it will be understood to be constructed in the same manner as that described above and shown in FIGS. 1-6. 
     These and other advantages of the present invention will be understood from a reading of the background of the invention, the summary of the invention, the brief description of the drawing FIGS., the detailed description of the preferred embodiments, and the appended claims.