Abstract:
A lymphatic pump apparatus for use under the thoracic cage of a human patient in a supine position. The apparatus comprises a mat which supports a pair of longitudinal lifting members positioned to be parallel to and on opposite sides of the spine under the angle of the ribs. The apparatus provides intermittent rib cage excursion, or anterior displacement of the ribs, to assist and increase lymphatic flow. Enhancement of lymphatic flow is beneficial in numerous disease states characterized by capillary leak and abnormal excursion of fluids and proteins into the interstitial spaces.

Description:
This application claims the benefit of the filing date of provisional application Ser. No. 60/365,681, entitled “Lymphatic Pump Apparatus,” filed Mar. 18, 2002, now abandoned, the contents of which are incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to devices for lifting and manipulating the thoracic cage to improve lymphatic flow. 
     BACKGROUND OF THE INVENTION 
     In several severe disease states, there is an increase in capillary leak resulting in an abnormal fluid and protein shift into the interstitial spaces. Such disease states include, for example, systemic inflammatory response syndrome and septic shock. This fluid shift may result in ascites, hepatic congestion and other forms of organ congestion, which may be fatal. There is a need for an apparatus that will combat this dangerous fluid dysfunction by enhancing lymphatic flow. 
     SUMMARY OF THE INVENTION 
     The present invention is directed to a lymphatic pump apparatus for use under the thoracic cage of a human patient in a supine position. The apparatus comprises a mat sized to fit under the patient&#39;s thoracic cage while the patient is in a supine position. The apparatus also includes a lifting assembly comprising at least one lift member provided in the mat. The lifting assembly is movable between a retracted position and an extended position and adapted in size and position to lift and lower at least one side of the thoracic cage of the patient. A control assembly is provided to control the lifting assembly to provide intermittent movement of the lifting member. 
    
    
     BRIEF DESCRIPTION OF THE DRAWING 
     FIG. 1 is a perspective view of a lymphatic pump apparatus constructed in accordance with the present invention. 
     FIG. 2 is a plan view of the apparatus positioned under a patient (shown in phantom). 
     FIG. 3 is a side view of the apparatus positioned under a patient (shown in phantom). 
     FIG. 4 shows a cross sectional view of the apparatus positioned under a patient (shown in phantom) in a supine position. 
     FIGS. 5A-5C show sequential operation of the lymphatic pump apparatus under a human torso. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Turning now to the drawings in general and to FIG. 1 in particular, there is shown therein and designated by the reference numeral  10  a lymphatic pump apparatus made in accordance with the present invention. The apparatus  10  is designed for use under the thoracic cage of a human patient in a supine position, as illustrated in FIGS. 2 and 3. 
     The apparatus  10  comprises a mat  12  sized to fit under the patient&#39;s thoracic cage while the patient  14  is in a supine position. The overall size of the apparatus  10  and its mat  12  relative to the patient&#39;s body may vary. In addition, the present invention contemplates mats of different sizes to accommodate patients of different sizes from children to large or tall adults. 
     The apparatus  10  further comprises a lifting assembly  20 . The lifting assembly comprises at least one lifting member, and preferably a pair of lifting members  22  and  24 , provided in the mat  12 . Each lifting member  22  and  24  is movable an extended position and a retracted position. In FIG. 1, the lifting member  22  is in the extended position and the lifting member  24  is in the retracted position. In a manner to be described in more detail hereafter, each lifting member  22  and  24  is adapted in size and position on the mat to lift and lower one side of the patient&#39;s thoracic cage. Thus, as shown in FIGS. 2 and 3, the preferred lifting members  22  and  24  are elongate members, each of which is positioned in the mat  12  lateral to the spine  26  of the patient  14  and generally under the angle of the ribs (not shown). One lifting member  22  is adapted to lift and lower the left side of the thoracic cage of the patient  14 . The other lifting member  24  is adapted to lift the Tight side of the thoracic cage of the patient  14 . 
     Preferably, the lifting members  22  and  24  run parallel to the vertebral column from approximately at least the fourth thoracic vertebrae (T 4 ) to approximately at least the tenth thoracic vertebrae (T 10 ) and lying just underneath the angle of the ribs. More preferably, each lifting member  22  and  24  runs parallel to the vertebral column from approximately at least the first thoracic vertebrae (T 1 ) to approximately at least the twelfth thoracic vertebrae (T 12 ). 
     With reference now to FIG. 4, a preferred mechanism for operating the lifting assembly  20  will be described. In the preferred construction, each of the lifting members  22  and  24  comprises at least one inflatable chamber. The fluid media used for inflation may be air or some other gas or a liquid such as water. More preferably, each comprises a plurality of lifting chambers  28   a-d  and  30   a-d , respectively. 
     In this embodiment, then, a fluid pump  32  will be included for inflating and deflating the lifting members  22  and  24 . The fluid pump  32  may be fluidly connected to the chambers  28   a-d  and  30   a-d  by a system of conduits designated collectively at  34 . For optimum effectiveness, the lifting member  22  and  24  should extend and retract very rapidly. Various pump/vacuum devices are commercially available for this purpose. 
     It is advantageous to include in the apparatus  10  a control assembly  40  adapted to control the lifting assembly to provide intermittent movement of the lifting members  22  and  24 . The control assembly  40  may be used to control the fluid pump  32 , as well as several other variables which may be involved in the operation of the apparatus  10 . Where the lifting members  22  and  24  comprise multiple chambers, such as the chambers  28   a-d  and  30   a-d , the control assembly  40  may be adapted to selectively and separately inflate one or more of the chambers. In its most preferred form, the control assembly  40  will be designed to inflate the lifting members  22  and  24  alternatingly, so that only one side of the patient&#39;s chest is lifted at a time. 
     The control assembly  40  may be programmable to provide selective frequency, duration and sequence of the extension of the lifting members. Still further, the control assembly  40  may be programmed to provide cycles of operating and rest phases of predetermined duration and frequency. To optimize the therapeutic effect of the apparatus, the volume of each chamber or compartment may be varied in order to achieve the preferred amount of displacement, expansion or excursion of the chest wall. Suitable control devices are commercially available, such as those used for cardiovascular compression systems and the like. 
     The control assembly  40  may be adapted to operate the lifting assembly  12  automatically with an artificial respirator, such as a ventilator  42  (FIG.  4 ), Bi-pap machine, C-pap machine or any other form of artificial respiratory device. In this way, expansion and contraction of the lifting members  22  and  24 , and the concomitant rib cage excursions, may be coordinated with the phases of respiration, i.e., inhalation and exhalation. In addition, respiration sensors (not shown) may be used to provide data to the control assembly  40  indicating the patient&#39;s natural or unassisted breathing pattern. In this way, operation of the apparatus  10  may be coordinated with the patient&#39;s inhalation and exhalation. 
     With continued reference to FIG. 4, the structure of the mat  12  will be described. For the patient&#39;s comfort, the mat  12  may comprise an upper layer  44  made of foam or another suitable resilient material. For support, the mat  12  may be provided with a second support layer  46  comprising ribs  48 , stays or bars, which may run transversely or parallel, or both. The mat  12  preferably will also include a cover  50  made of suitable material. 
     Having described the structure of the apparatus  10 , its use will now be explained. The function of the lymphatic pump apparatus  10  is to cause thoracic rib cage excursion or anterior displacement of the ribs while the patient is in a supine position. This will increase lymphatic flow. While not wishing to be bound by theory, it is believed that the increase in lymphatic flow is generated by pressure gradients caused by the rib cage excursion. Other contributing factors may be the effect on the diaphragm on such pressure gradients, as well as other possible effects on the autonomic nervous system. 
     The apparatus  10  is properly positioned under the patient  14 , as illustrated best in FIGS. 2-4. The patient&#39;s medical parameters are studied, and a course of treatment is prescribed whereby the apparatus  10  will be operated according to predetermined parameters. The operation of the apparatus  10  is illustrated in FIGS. 5A-C. In FIG. 5A, the apparatus  10  is shown with the lifting members  22  and  24  both in the retracted position. In FIG. 5B, the left side of the patient&#39;s chest is raised by extension of the lifting member  24 , while the lifting member  22  is retracted. In FIG. 5C, the right side of the patient&#39;s chest is raised by extension of the lifting member  22 , while the lifting member  24  is retracted. This process is repeated automatically in the prescribed pattern, and for the prescribed duration. The patient&#39;s clinical signs are monitored so that the operation of the apparatus  10  can be adjusted, or terminated, as indicated. 
     The apparatus of the present invention, thus, may be used as a treatment aid in removing excess interstitial fluid, i.e., edema, from tissues and organ systems in the thoracic and abdominal areas, and other bodily organs and parts. Increase lymphatic flow will promote reclamation of proteins and albumen from the interstitial space, aide the immune system, move toxins and endotoxins from the interstitial space into the lymph fluid, which in turn is delivered to the venous system. 
     The present invention may be used in the treatment of any disease or disease states where increased lymphatic flow will have a beneficial effect. Such disease states include but are not limited to those disease states where there is an increase in capillary leak, such as occurs with systemic inflammatory response syndrome and septic shock. More specifically, the lymphatic pump apparatus of this invention may be used in the treatment of and the consequences of capillary leak and dysfunction, such as in acute respiratory distress syndrome, ascites, hepatic congestion and other forms of organ congestion where increased lymphatic flow would promote a beneficial effect. Of course, use of the apparatus  10  may be contraindicated in patients with chest trauma or other conditions that would be adversely affected by repeated manipulation of the thorax. 
     Changes can be made in the combination and arrangement of the various parts and elements described herein without departing from the spirit and scope of the invention.