MXPA98004757A - Apparatus to compress the chest, to treat a cardi stop - Google Patents

Abstract

The invention relates to an apparatus for increasing intra-thoracic pressure in order to resuscitate patients affected by cardiac arrest. The apparatus comprises a flexible, substantially inelastic strap, which is passed around the patient's chest and fixed to a force converter. The force converter converts a force directed downward, in a resultant directed towards the chest, that presses the sternum, and in two resultants that adjust or tighten the strap. The force converter comprises a pair of arm assemblies, each of which has a pair of spaced arms that are pivotably mounted on a base. The base is positioned near the sternum of the patient, and the ends of the strap are fixed to one end of each set of the arms. The opposite handle ends of the arm assemblies are pressed towards the chest, which causes the adjustment or tensioning of the belt and compression of the cavity of the arm.

Description

-APARATE TO COMPRESS THE CHEST, TO DEAL WITH A CARDIAC STOP TECHNICAL FIELD The present invention relates in broad terms to the field of medical devices, and is more specifically preferred to an apparatus for increasing blood flow by compressing the thoracic amount of a person suffering cardiac arrest.

PREVIOUS ART During cardiac arrest, it is desirable to generate blood flow by external means in order to maintain the viability of the brain and heart.

Traditionally, the external means to generate blood flow, has been manual cardio-pulmonary resuscitation, CPR (cardiopulmonary resuscitation). Using the CPR, the lifeguard tilts the patient's head backwards, raises the jaw in order to unclog and align the airway, and presses the sternum in 1 1/2 to 2 inches (from 3.81 to 5.08 cm), 15 times (at a rate of 80 to 100 oppressions per minute), after which the rescuer gives the patient 2 full breaths. These 15 oppressions REF: 27742 and 2 breaths, are repeated cyclically. Currently, the community doing research in the field of CPR, believes that the flow produced by external means, can be explained by a theoretical mechanism, or by a combination of two theoretical mechanisms: the mechanism of the "heart pump" and the mechanism of the "thoracic pump". According to the mechanism of the heart pump, the flow of blood caused by external means is due to the direct mechanical compression of the heart. During compression, blood is squeezed from the chambers of the heart, and during the release of compression (relaxation), blood flows into the chambers of the heart. The reversal of blood flow is impeded by the valves of the heart and vessels. According to the mechanism of the thoracic pump, the blood is pumped by external means, as a result of the cyclic increase and decrease of the intra-thoracic pressure. During compression, the intra-thoracic pressure increases, which causes the blood to be forced out of the blood vessels and organs located in the thorax, and blood flows to the peripheral tissues. During release, blood flows back to the thorax through the normal return of the veins. In this method, the reverse flow is prevented by the valves of the veins.

Most researchers believe that both mechanisms are active to some degree. However, the methods currently in use, and the devices currently in use, to promote the flow of blood by applying an external force, are oriented to only one of both mechanisms. In order to maximize blood flow, a device is needed that takes advantage of both mechanisms. A variety of devices have been developed to increase the flow of blood and / or air in the chest cavity of a patient affected by cardiac arrest. In US Patent No. 2 071 215, assigned to Petersen, a piston and cylinder arrangement is shown attached to both ends of a belt or sash that surrounds a patient's chest, the expansion or compression of a fluid in the combination of piston and cylinder, tightens and loosens the belt in order to ventilate the lungs. This device is large and heavy, and depends on a compressed fluid as a source of drive energy. In US Patent No. 3 425 409, assigned to Isaacson and Other (s), an apparatus is disclosed for compressing the sternum by a downward force generated by a piston. There is a strap placed around the chest in order to minimize body damage and the air is applied to the patient's airway.

In US Patent No. 5,287,846, assigned to Capjon and Other (s), an upper frame is shown resting on a patient whose back rests on a lower frame. Retractable strips extend from the upper frame and attach to the lower frame. There is a hydraulic cylinder that presses down on the chest. Barkalow, in US Patent No. 3 461 860, discloses a device that uses a pneumatic plunger to pneumatically compress the sternum at a predetermined distance. A mechanical ventilator was added to this device, in the American Patent No. 4 326 507, in order to ensure adequate ventilation and increase breast volume. This device had limited success due to its complexity that requires a trained staff to use it. A similar device is that which has been disclosed in US Patent No. 4 060 079, by Reinhold. This device is merely a portable unit. Bloom, in US Patent No. 4 388 924, shows a device for compressing the sternum, which uses an air cylinder to press the patient's chest for cardiac arrest. This device, like many others based on a chest compression device, is large and heavy. Ne an and Other (s) in US Patent No. 4 424 806, shows a pneumatic vest to generate an increase in thoracic pressure. This vest uses the concept of "thoracic pump" to exert a greater pressure on a larger area, under the assumption that if it could compress and release more important organs, it would have a greater blood flow. By releasing the compressive force, the chest would return to its normal size and drag the blood back to the most important organs. There would be a positive flow of blood due to the one-way valves in the vascular network. The Newman device is not easily portable, apart from being substantially complex. In U.S. Patent No. 4,928,674, Halperin and Other (s) disclose a similar vest that is also not portable. Lach and Other (s), in US Patent No. 4 770 164, reveal a circumferential band and a collector band used to generate an increase in thoracic pressure. Although it can be operated both manually and mechanically, this device requires the use of a board to guide the band around the chest. The use of bands or belts to generate an increase in intra-thoracic compression in order to alleviate respiratory disorders, has been disclosed in US Patent No. 651,962, assigned to Boghean. This device is to loosen and periodically adjust the band around the chest of a patient, in order to treat a respiratory disease by regulating the periods of respiration as well as by regulating the magnitude or depth of the breath. In U.S. Patent No. 3,777,744, Fryfogle and Other (s) disclose a breathing aid, consisting of a strap and a handle that adjusts the strap in order to expel excessive residual air present in the lungs. Among the other devices known to the Applicants and in which circumferential bands are used to generate a compression force on the lower abdomen and chest to aid in the compression of the lungs for respiratory purposes, US Patent No. 2 899 955 is included. , from Huxley, US Patent No. 3 368 581 from Glascock, and US Patent 2 754 817 from Nemeth. On the other hand, the use of inflatable bladders positioned around the chest or abdomen has been disclosed in U.S. Patent No. 3 481 317 to Drennen, U.S. Patent No. 3 120 228 to Huxley, U.S. Patent No. 3 042 024 by Mendelson, US Patent No. 2 853 998 by Emerson, US Patent No. 2 780 222 by Polzin, US Patent No. 2 071 215 by Petersen, US Pat. No. 4 424 806 by Nean and U.S. Patent No. 4,928,674 to Halperin. In U.S. Patent No. 2 699 163, assigned to Enstroem, a breathing device is shown to ventilate a patient's lungs.

In U.S. Patent No. 5,295,481, assigned to Geeham, there is shown a device for compressing the chest, comprising a mechanical device for compressing the chest, of a "T" shape, provided with a suction cup. The central stem attached to the cup can be compressed beyond the lips of the cup, and it is possible that it bruises or injures the patient in some way due to the concentration of force in the patient, by the tip of the rod. In US Patents No. 4 397 306, assigned to Weisfeldt and Other (s), and 1 399 034, assigned Taplin, large mechanical devices are shown to compress the chest of a patient affected by cardiac arrest. Szpur, in U.S. Patent No. 5,407,418, discloses the pulsating compressor apparatus, operated by a motor or the like, to stimulate the flow of blood within the vessels of a patient's hand or foot. The device periodically applies a concentrated force against a localized region of the foot or hand. Despite the prior art, there remains a need for a device that effectively increases the flow of blood in the organs of a patient affected by cardiac arrest. This device should be really portable and usable by a person of medium physical strength and ability.

BRIEF DESCRIPTION OF THE INVENTION The invention consists of an apparatus for increasing the blood flow in a patient, for example of a person having cardiac arrest. The apparatus comprises a contoured base so as to settle close to a central region of the patient's chest. Also included is a manual actuator and a substantially non-elastic strap that serves to be wrapped around the patient's chest. The invention also comprises a force converter, mounted on the base. The force converter is connected to the actuator, and has belt connectors to connect the opposite ends of the belt. The force converter serves to convert a force manually to the chest, in a resultant force that compresses the chest. The resulting force that compresses the chest is directed through the base, towards the chest. The force applied manually to the actuator is converted, in addition to the resultant force that compresses the chest, into results that adjust the strap, applied to the belt connectors, and directed tangentially toward the chest. The invention considers that converting comprises first and second assemblies. The first set has a pair of arms separated and parallel to each other, rigidly connected to the ends of a handle by means of a first handle that can be grasped by the hand. The arms of the first assembly are also rigidly connected to the opposite ends of the belt, by means of a first strut. The arms of the first assembly are pivotably mounted to the base in a fulcrum of the first assembly located in an intermediate position between the handle and the ends of the belt. The second assembly is substantially similar to the first assembly, and both assemblies are pivotably mounted to the base, forming a scissor-like arrangement. A force applied to the extremities of the handle pivots the scissor assemblies, which form a pair of levers. The strut ends of the assemblies are levered towards each other, thereby fitting the strap to the struts. One of the objects of the present invention is to provide an apparatus having a flexible strap that is wrapped around the chest of a patient suffering cardiac arrest. The device adjusts the strap while depressing the chest, the combination of which raises intra-thoracic pressure, which promotes blood flow.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a perspective view, illustrating an embodiment of the present invention, in an operable position; Figure 2 is a sectional side view, illustrating the external positions of the arm assemblies of the embodiment of the present invention shown in Figure 1; Figure 3 is a schematic view, illustrating a force diagram; Figure 4 is a schematic view, illustrating an alternative force converter; Figure 5 is a schematic view illustrating an alternative force converter; Figure 6 is a schematic view, illustrating an alternative force converter; Figure 7 is a schematic view, illustrating an alternative force converter; Figure 8 is a schematic view illustrating an alternative force converter; Figure 9 is a schematic view, illustrating an alternative embodiment of the present invention; Figure 10 is a sectional end view, illustrating a primary mover (prime mover actuator) forming part of the present invention; Figure 11 is a perspective view, illustrating an alternative embodiment of the present invention; Figure 12 is a schematic view, illustrating an alternative embodiment of the present invention; Figure 13 is a perspective view, illustrating an embodiment of the present invention; Figure 14 is an enlarged, perspective view of an embodiment of the present invention; Figure 15 is a sectional side view, illustrating the end positions of the arm assemblies of the embodiment of the present invention, shown in Figure 13; Figure 16 is a sectional side view, illustrating a lower part of the base; and Figure 17 is a side view, in section, showing another lower part of the base. In the description of the preferred embodiment of the invention, illustrated in the drawings, a specific terminology will be used, for reasons of clarity. However, it is not our intention that the invention be limited to the specific terms so selected, and it should be understood that each of the specific terms includes all of its technical equivalents that operate in a similar manner to carry out a similar purpose.

DETAILED DESCRIPTION OF THE INVENTION In Figure 1 it shows the apparatus 10, which is an embodiment of the invention, in its operable position in and around the chest 12 of a patient. The base 14 is a plate or block, which is rigid (preferably of plastic material), which preferably has a contoured cushioned surface so as to be seated against the central region of a patient's chest 12, near the sternum. The lower part 92 of the base 14, is seated against the upper region of the chest, 12, and may have an adhesive pad 500 (shown in Figure 16) or a suction cup 502 (shown in Figure 17) to adhere to the chest 12, such that the pull on base 14 will cause chest 12 to be pulled for decompression. The base 14 contains a switch 70 and a pair of lights 72. Additionally, the base 14 contains a battery, an indicator of the battery charge and a sound generator (not visible in Figure 1), which sound generator emits an audible periodic signal. The visible and audible signals indicate the frequency to a lifeguard person of a compressive force that he or she must apply to the apparatus 10. One or more of the audible or visible signals may also prompt the lifeguard to apply ventilation. The base 14 also contains a sensor or force detector, such as a strain gauge, and an indicator, 74, which indicates the force exerted on the chest 12 to warn the lifeguard about a potential injury due to the excessive force. A limiter should be added to limit part of the force applied to the patient, to a specified maximum. The first set of arms, 16, consists of a pair of arms spaced apart and parallel to one another, 22 and 24, which are made of a light material of high tensile strength, such as a plastic material. The second set of arms, 18, has arms that are spaced apart and parallel to each other, 26 and 28, substantially similar. A pair of rods, 37 and 38, rigidly grip the parallel spaced arms of the assemblies 16 and 18, respectively. A pair of hand actuators, which are preferably two hand-accessible cylindrical handles, 30 and 32, are rotatably mounted between the spaced arms and parallel to each other, of the first and second arm assemblies, 16 and 18, around each other. the rods 37 and 38, respectively. A pair of struts 36 and 38, similar to rods, preferably metallic (the strut 36 is not visible in Figure 1) are mounted rigidly on the ends of the arms, opposite to the handles 30 and 32.

The rigid arm assemblies, 16 and 18, pivot with respect to each other around the pivot pin 20, which is preferably a stainless steel bolt. The pin 20 extends longitudinally through the base 14, and extends by force of each of the longitudinal ends in order to be pivotably fixed to each of the arms 22, 24, 26 and 28. The sets of arms , 16 and 18, are arranged in a configuration similar to that of a scissor. This configuration is designed to convert a small force into a larger force. This is effected by the scissor-type configuration having a pair of levers with a fulcrum in common, the fulcrum being located at a given distance with respect to the center of the levers. A large displacement of the handles 30 and 32 causes a relatively small displacement of struts 34 and 36. In elementary physics, it is understood that work is equal to the product of displacement force, and that the force applied to produce a displacement in one of the limbs of a lever should be equal to the product of force by displacement at the opposite end of the lever. The principle of conservation of work results in the following equation: FSDS = FhDh (Equation 1) in which the sub-index "s" indicates the force or displacement in struts 34 and 36, and the sub-index "h" "indicates the force or displacement in handles 30 and 32. If we solve Equation 1 to obtain the strength of struts 34 and 36, we obtain: Fs = FhDh / Ds (Equation 2) This displacement in struts 34 and 36 (Ds in the Equation 2), will be smaller than the displacement on the handle (Dh in Equation 2). By separating the part of the displacement of part 2 in parentheses, the following is obtained: Fs = Fh (Dh / Ds) (Equation 3) Since the displacement in the struts is smaller than the displacement in the handles, the displacement portion of Equation 3, will be a number of times greater than 1, which when multiplied by the force in the handles, will allow to obtain a force in the struts that is greater than the strength in the handles. It is this larger force at struts 34 and 36, effected by the force applied to the handles, which is used to artificially induce or accentuate the flow of blood in a patient. The pivoting movement of the arm assemblies, 16 and 18, is a simple and reliable action that can be performed by virtually anyone. Doing so requires a small force, and creates a larger force that has to be applied to the chest 12 of a patient. The force on the struts, 34 and 36, could not be generated by an average person during the period of time required to treat a patient affected by a cardiac arrest, without the aid of a mechanical device. Two stroke limiters, made of stainless steel, 52 and 54, are mounted pivotably on the arms 22 and 24 and are fixed in a sliding manner to the arms 26 and 28. The limiters 52 and 54 serve the purpose of limiting the displacement of relative pivoting of sets 16 and 18 by mechanically restricting their movement. Unlimited displacement between both sets 16 and 18 could result in excessive compression force on a patient's chest 12, which could injure the patient. An alternative to the arm assemblies, 16 and 18, shown in Figure 1, are the arm assemblies, 416 and 418, shown in Figure 13. The arm assemblies, 416 and 418, consist of the separate and parallel arms. among themselves, 422, 424, 426 and 428, respectively. The curved configuration of the arms 422 - 428 that make up the arm assemblies, 416 and 418, have proven to be more advantageous than the angled configuration of the arms that make up the arms, 16 and 18, shown in FIGURE 1. The advantage is that finds primarily in the middle to limit the relative displacement of the arm assemblies, 416 and 418. The preferred means for limiting relative movement is shown in greater detail in Figure 14. As the arms 422 and 426, shown in FIG. Figure 14, pivoted about the common fulcrum located on the pivot pin, 430, pivots toward the stopping pin, 432. The stopping pin, 432, extends through one of the three holes formed in an upright 434 which extends rigidly from the base 414. The arm 422 has three shoulders 440, 442, 444, which face the stopping pin 430. The arm 426 has three similar shoulders, 446, 448, and 450. In its relaxed position it shows In Figure 14, arms 422 and 426 have clearances of a predetermined distance between corresponding shoulders. For example, the clearance between shoulder 422 and shoulder 448. is of a predetermined size when arms 422 and 426 are in their relaxed position. As the arms 422 and 426 are pivoted towards each other, the clearances between the shoulders decrease in size. In order to ensure that the clearance between a particular pair of ridges does not decrease below a specified minimum, the stopping pin, 432, is placed in one of the three holes 452, 454, or 456, formed in the assembly 434. Each of the holes has an axis that extends in a particular gap. Since the three clearances between the six shoulders 440-450 are of different lengths, the position of the stopping pin 432 on the post 434 will affect the distance that the arms 422 and 426 can travel until two associated ridges are seated against the pin. of detention 432, which restricts any further movement. For example, in Figure 15 the arm assemblies 416 and 418 are shown in their relaxed positions and in dashed lines in an extended position. In the extended position, when the stopping pin 432 is positioned in the hole 456 of the assembly 434, the shoulders 440 and 446 are seated against the sensing pin, 432, in order to limit the extension of the arm assemblies, 416 and 418. The belt 40, which extends around the front, sides and back of the chest, is substantially inelastic and flexible. A plurality of indicator legends, 50, have been printed on the exposed surface of the belt 40. The belt 40 is fixed on the strut 34 on one of the sides of the chest, 12, and extends around a major portion of the circumference of the chest, 12, in order to be fixed on the other strut 36. When the assemblies 16 and 18 pivot around the pivot pin, 20, the belt 40 is adjusted by the struts 34 and 36 to which the belt 40 is fixed. While the strap 40 is described as extending around the front, sides and back of the chest, the strap may consist of two or more component parts, such as a pair of straps. This pair of straps should extend from their attachment to struts 34 and 36, extending downwardly beyond the sides of the patient's chest toward the rigid attachment to a board that covers the width of the back of the chest. Therefore, "a strap passed around the chest" may consist of two or more strap components that extend around the portions of the chest circumference in combination with other rigid or flexible components. The relaxed and half-actuated positions of the arms of the apparatus 10 are shown in Figure 2. The first and second sets, 16 and 18, are shown in their relaxed position and (in dotted line) at the midpoint of its position activated. Sets 16 and 18 are pressed into their relaxed position by a spring (not shown) which could be a torsion spring that extends around the pin 20 and which is connected to the assemblies 16 and 18. The handle ends, 80 and 82, of the arms 22 and 26, pivot along the an arcuate path downward and away from each other, and the ends of the belt, 84 and 86 of the arms 22 and 26, pivot upward and toward each other in an arched path subtending the same angle as the legs. handle tips, 80 and 82. The ends of the belt, 88 and 90 (which are the ends at b of belt 40 and which are attached to struts 34 and 36), follow the ends of the belt, 84 and 86, of the arms, to an ascending and separated position more proximally. Since the belt 40 is substantially inelastic, its circumference will decrease under the force applied to it by the struts 34 and 36, whereby the belt 40 is adjusted around the chest 12. The belt 40 extends through slits 44. formed on a board 42, which, when in use, positioned below the chest 12 of the patient. The strap 40 preferably sits against a sliding mechanism 43 which allows the belt 40 to slide along the length of the chest 12 for positioning the belt 40 on the chest 12. The board 42 is made of a strong material and lightweight such as a plastic material, and it is wide enough to span the width of the breasts of a large majority of the population. The board 42 has a raised padded portion, 46, which raises the neck of the patient above its head in order to open the respiratory ducts, and the board 42 preferably has handles 250 and 252 (shown in Figure 9) for transporting board 42, with or without a patient lying on it. The board 42, the fixed strap 40 and the assemblies 16 and 18, are all hung on a wall by passing one of the hooks through the handles 250 and 252 or by some other conventional means for hanging, and can be articulated near the center for folding during storage. Figure 2 shows in hidden lines an oxygen tank 100 and a mask 102, contained within a chamber 104 formed in the board 42. Through the gate 101 can be seen in a manometer 103 indicative of the amount of oxygen available in the tank 100. The raised position 46 of the board 42 has been adapted to the formation of a cylindrical chamber 104 in which it is easy to store the oxygen tank 100. If necessary, the mask 102 can be removed from the chamber 104. placed over the patient's mouth to obtain greater ventilation of the chest lungs. The apparatus 10 is operated in the following manner, referring to Figures 1 and 2. The victim is placed on the board 42 with his chest 12 in the position shown in Figure 1. The back of the chest of the patient's chest 12, it sits against the surface of the board 42, resting the neck of the patient, in the raised portion 46, and resting its head on the horizontal surface on which the board 42 is located, such as a floor. The base 14 of the apparatus 10 is placed in approximately the center of the patient's chest 12, near the sternum. The strap 40 is segment extended upwardly from the board 42, between the arms and the chest 12, and around the opposite sides of the chest 12, in order to follow the contour of the chest 12. The strap 40 is positioned as high as possible on the chest 12, and as high as possible under the armpits. The belt 40 is then extended around the struts 34 and 36, passing first between each strut 34 and 36 and the base 14. The base 14 is more accurately positioned near the center of the chest 12, matching the indicative legends 50 on the belt 40 on the opposite sides of the base 14. The indicative legends 50 are alpha-numeric characters spaced at equal distances along the length of the belt 40., in a preferably identical arrangement in both ends of the belt 40. Of course the indicative legends could be bands of colors, or other indicators. Once the belt 40 extends around the struts 34 and 36, the ends of the belt 40 are folded back over the portion of the belt 40 which contacts the chest 12, and are fixed thereto by means of fasteners However, before fixing, the indicator legends 50 on both struts, 34 and 36, must coincide. For example, the number "3" is shown as the highest number on the belt visible in Figure 1. In that example, the same number ("3") should be greater than the number visible on both struts 34 and 36, which indicates that an equal length of the strap 40 extends from the board 42 towards the strut 34 that towards the strut 36, and that therefore the base 14 is centered on the chest 12. After fastening the strap 40 to the struts 34 and 36, the pins of the stroke limiter, 60 and 62, extend into the holes 1 and 4 in the arms 26 and 28. Since the number "3" is the largest visible number on the belt 40, and the limiter pins, 60 and 62, are placed at the distal end of the six holes 1 -6 in the arms 26 and 28. If the number "2" were the largest visible number on the belt 40, the central holes would be used. and 5 of the 6 holes 1 - 6 in the pivoting arms, 26 and 28, since the number "2" would indicate a breast with a circumference a greater than if "3" were the largest visible number. The race when the number "2" is the largest visible number is greater than when "3" is the largest visible number. This means that for a breast with a larger circumference, the apparatus would be allowed to cause a greater displacement of the chest 12. If the arm assemblies, 416 and 418, shown in Figure 13, were used instead of the sets of arms, 16 and 18, shown in Figure 1, then the greatest visible number on the belt 40, indicate the positioning of the stopping pin 432 on the pillar 434. For example, since the number 3 is the largest visible number in the belt 40 in Figure 1, the stopping pin, 432, would be placed in hole 456 having an indicator legend "3" close to it. The "3" indicator is visible in Figure 15, but Figures 13 and 14 only the "1" and "2" indicators can be seen. Once the apparatus 10 has been positioned with the belt 40 around the chest 12, the base 14 is centered and the limiters 52 and 54 are in their correct position for the visible indicators 50 on the belt 40, the lifeguard presses the switch 70. This causes the lights 72 to start emitting a periodic visible signal, and the base 14 begins to emit a periodic audible signal synchronized with the lights 72. The lifeguard then grabs the handles 30 and 32 with the hands and, with a force directed downward toward the chest 12, pushes the handles 30 and 32, causing them to pivot about the pivot pin, 20, whereby the arms 22, 24, 26 and 28 are pivoted through arcuate paths around the pin 20 This pivoting movement causes the struts 34 and 36 at the opposite ends of the arms with respect to the handles 30 and 32 to pivot about the pivot pin, 20, in a direction away from the chest 12, but with a displacement that is less than that of the handles 30 and 32. The pivoting of the struts 34 and 36, pulls the ends of the belt 40 closer to one another, thereby adjusting or tightening the belt 40 around the chest 12. Since the belt 40 is inelastic, the adjustment the belt 40 compresses the chest 12. The arched movement of the handles 30 and 32, is limited to a maximum displacement by the stroke limiters 52 and 54, when the pins 60 and 62 make contact with the ends of the slits 64 and 66. The force in the handles 30 and 32, is released, and then resumed by the rescuer after the handles 30 and 32 have returned to their original positions. By cyclic oppression with a force directed downwards, and releasing the handles 30 and 32 (preferably in phase with light 72), the lifeguard adjusts and cyclically releases the strap 40 around the patient's chest. The base 14 concentrates part of the adjustment force of the belt, in the center 12, and prevents the punching of the chest by means of the scissor-type assemblies, 16 and 18. The strap 40 that fits around the chest 12, represents the method of the "thoracic pump" of the artificial induction of blood flow in a patient affected by cardiac arrest by the application of a broad compressive force to a large area. The great strength is due to the effect of the lever created by the scissor-type assemblies 16 and 18, and the large area is the circumference of the chest 12. As the first set 16 and the second set 18 are forced down the chest , the lower part 92 of the base is forced downwards along a path directed towards, and preferably perpendicular to, the surface of the chest, by the force directed downwards on the handles 30 and 32. Therefore, each oppression of the first and second sets 16 and 18 results in a downward compression of the center of the chest by the base 14. This is the method of the "heart pump" to induce blood flow by compressing the heart between the spine and the sternum. The compression of the organs by means of the present invention takes advantage of both methods, that of the "thoracic pump" (a strap that adjusts and loosens or loosens) and the method of the "heart pump" (oppression of the chest by the base 14), to circulate the blood through the blood vessels and, when it loosens, it drags the blood back to the organs. Each time the pressure is increased, the blood is extruded from the organs. Each time the pressure increases, it is squeezed out of the organs (and the air is expelled from the lungs) and throughout the vascular system. When it loosens, another blood is made to enter. Since the veins have a series of one-way valves, the periodic raising and lowering of the chest pressure by the present invention creates an artificial blood flow that supplies the necessary elements for the vital organs, such as the brain, which increases the patient's chances of survival. The pivoting assemblies 16 and 18 comprise a force converter that converts the oppression force on the chest, directed downwards, when the handles 30 and 32 are applied, in multiple resultant forces. Said resultant forces include a downward directed force applied from the base 14 to the chest 12 and two equal tangential forces applied by the points 34 and 36 to the belt 40. The forces are applied tangentially to the chest 12, since the belt 40 passed through around chest 12 and tightened, it must be tangential to the surface of chest 12, with which it makes contact on the sides of the chest, as shown in Figure 1. Sets 16 and 18 comprise the force converter which is a device that converts the force applied manually to the handles 30 and 32, and directed towards the chest 12, in the previously described results (specifically, a resultant that compresses the chest and a pair of results that adjust the strap). A converter for converting the applied force described above into the resultants includes all equivalents to the preferred force converter. A converter does not have to limit itself to reorienting a specific force, but could expand, reduce or signalize, a device to generate other forces through the application of a force.

The force needed to generate sufficient pressure in the chest cavity to create a blood flow can be generated by an average person if a device correctly uses an applied force. In the position in which a patient affected by a cardiac arrest is found, a lifeguard would not normally be able without a leverage effect, generate a decent force on the patient's chest that is sufficient to generate the necessary intra-thoracic pressure without running the risk of producing an injury. The apparatus of the present invention uses the force that an average person can apply, and converts applied force applied force into resultant forces in the necessary directions, this while limiting the maximum displacement, in order to avoid possible injuries. The force converter described above, can be considered as a free body shown in Figure 3, having an applied force 112 directed downwardly on the converter 110. An opposing force 114 is applied by the chest against the converter 110, as a reaction to the opposing force 112. The tangential forces 116 and 118 are the belt forces, which extend circumferentially around the chest, pulling the converter 110. The converter 110 converts the downward directed force, 112, into resultant forces 120, 122, and 124. The resultant force 120 is directed toward the chest along a direction similar to that of the applied force 112. The resulting forces 122 and 124 apply a tangential tension force to the belt, which is tangential to the chest. of the patient. The preferred embodiment of the pressure of the preferred one of the present invention is a device for which the Applicants have discovered that it is advantageous to convert the downward force 112 into the three resulting forces 120, 122 and 124. The Applicants know that many apparatuses are equivalent to, and could replace, the preferred apparatus, to provide the force conversion, described in association with Figure 3. While it is impossible to list every mechanical device of which a person skilled in the art knows that it can convert a force applied to the desired resultant forces, some of the many equivalents are described herein. However, this is not an exhaustive list, and there are other equivalents, as people with expertise in the art will understand. Figure 4 shows a schematic illustration of a cam 140 and a pair of cam followers, 142 and 144. By applying a downward force by the cam 140 on a pair of inclined surfaces 143 and 145, the follower 142 will slide to the right and the follower 144 will slide to the left, whereby forces are exerted on the ends of the strap fixed thereto, the strap being adjusted. The cam 140 will slide down the inclined surfaces of the followers 142 and 144, and reach the horizontal surfaces 146 and 148, it will stop abruptly - exerting a downward force on the surface below the followers 142 and 144, which could be the basis of the present invention. The apparatus of Figure 4 is equivalent to the preferred force converter apparatus. Figure 5 shows a schematic illustration of a first eccentric, 150, and a second eccentric, 152, pivotably mounted to a base 154. A manual actuator, 156, is fixed to a second pivot in each eccentric. A pair of strap ends, 158 and 160, are wrapped around the eccentrics 150 and 152, respectively. When a force directed downwardly is applied on the actuator 156, the eccentrics 150 and 152 pivot about the pivot points, exerting a force on the belt ends, 158 and 160, which causes an adjustment or tensioning of the belt. The eccentrics 150 and 152, having sufficient downward force on the actuator 156, will impact the base 154, exerting a downward directed force on the base 154, as in the preferred embodiment. The apparatus of Figure 5 is equivalent to the preferred form. In Figure 6 a schematic illustration of another equivalent of the preferred embodiment is illustrated, which includes an actuator 170 to which a downward directed force is applied. Actuation 170 has a two-sided serrated surface, 172, which is interengaged with a pair of gears 174 and 176. The gears 174 and 176 are pivotably mounted on a base 178, and a pair of belt ends, 180 and 182, are wrapped around a pair of drums. 184 and 186 in each of the gears 174 and 176. The toothed surface 172, by applying a force directed downwardly on the actuator 170, causes the intermeshing gears 174 and 176, to rotate, thereby applying a force to the ends 180 and 182 of the belt. The actuator 170 makes an impact on the base 178 when it is driven to a certain extremity, whereby a downward directed force is exerted on the base 178, as in the preferred embodiment. In Figure 11 another alternative mechanical apparatus 260 is shown, which is equivalent to the preferred embodiment. The apparatus 260 has a pair of pivoting arms 262 and 264 that pivot about a pivot axis 266 on a base 268. A belt 270 is fixed at its opposite longitudinal ends to the arms 262 and 264. The base 268 is positioned on the chest 272 of a patient, the strap 270 is circumferentially extended around the chest 272, and fixed to the handles 262 and 264. A downward directed force is applied to the handles 262 and 264 whereby the strap 270 is adjusted to As the arms 262 and 264 pivot about the pivot axis 266. In addition to the adjustment of the belt 270, the base 268 is forced down onto the chest 272. In Figure 12 a two-chamber device is shown, having a base 300 and two pivoting arms 302 and 304. Two springs, 306 and 308, hold two arms 302 and 304, pressed upwards, inside chamber 310. A plunger 312 is pressed away from chamber 310, by the spring 314. The belt 316 is fixed a to the arms 302 and 304. Upon the downward compression of the plunger 312, the arms 302 and 304 are rotated counterclockwise and clockwise respectively. This rotation produces an adjustment of the belt 316, and the patient's chest is compressed by the adjusted strap 316 and by the base 300, especially when the plunger 312 reaches the lower limit of the chamber 310. In many illustrations surrogate devices are shown. equivalents to convert a force applied to the desired resultant forces. Most of the described devices are purely mechanical in the preferred embodiment. As one person with skill in the art of mechanics will readily understand, there are many other equivalent substitutes for the preferred embodiment. Said devices are equivalent to the preferred embodiment or to one of the alternatives described in what follows and shown in the drawings. In addition to the purely mechanical alternatives to the preferred embodiment, it is of course possible to combine mechanical, electrical, hydraulic, and many other elements to arrive at a substitute equivalent to the preferred embodiment. Said equivalent combinations are examined in the following. Figure 7 schematically shows a mechanical, electrical, equivalent combination, including an actuator 200 and an electric motor 202 fixed to a base 204. The motor 202 has a pair of belt ends, 206 and 208 attached to a drive shaft. 210. When the actuator 200 is depressed, a pressure sensitive switch, 212, drives the motor 202, which rotates the drive shaft 210 and exerts a linear force on the ends 206 and 208 of the belt. As the force is applied to the actuator 200, this downwardly directed force is transmitted through the base 204 to the patient's chest which is located directly below the base 204. The embodiment of Figure 7 is equivalent to the preferred embodiment. In Figure 8 another equivalent to the present invention is shown, in a schematic illustration including a hydraulic cylinder 220, fluid pipes 222 and 224, and pistons 226 and 228 slidably mounted inside the cylinder 220. The ends 230 and 232 of the belt are mounted on the pistons 226 and 228. As it is When the actuator 234 is actuated, the hydraulic fluid is forced into the hydraulic cylinder 220, which forces the pistons 226 and 228 toward each other longitudinally, thereby exerting a force on the ends 230 and 232 of the belt. Actuation of the actuator 234 is accompanied by a downward force exerting a similar force on the chest of a patient located directly below the hydraulic cylinder 220. The actuator 234 could be attached to a central piston which compresses a fluid from a hydraulic cylinder. When the actuator 234 is actuated, the hydraulic fluid inside the cylinder is compressed and is transported through the pipes 222 and 224, and the pistons 226 and 228 are driven inward, as previously described. This embodiment is also equivalent to the preferred embodiment. It is possible to fix a power unit, such as a primary motor, to the apparatus 10 which could function as an actuator in order to apply a lateral force to the arm assemblies, 16 and 18, to operate them automatically and at regular intervals as periodic. As shown in Figure 9, the power or power unit 254 has a cable 256 attached to a belt 258. The device that provides a mechanical force to the belt 258 can be located in the power unit 254, and the cable 256 in this case longitudinally propelled as back and forth so as to tension and loosen the belt 258. Alternatively, the actuator which tightens and loosens the belt 258, could be located below the belt 258, and the cable 256 I would use it only to carry electric power or fluid pressure to the actuator. The power unit 254 can use computer controls to program the application of force. Figure 10 shows an example of a power unit 280 that applies a force that adjusts or tightens a belt 282 and presses a base 284. As the rod 286 extends in and out of the power unit, 280 , the base 284 is displaced up and down, whereby the chest 288 is pressed as described for the preferred embodiment. On the other hand, this same movement of the rod 286 adjusts and loosens the belt 282, as with the preferred embodiment. In order to ensure that the patient's lungs can be expanded to the desired degree, it may be necessary to include a full release indicator, together with the present invention. This full release indicator, together with the present invention. This indicator should have some means to warn the rescuer in the event that full release of belt tension has not taken place. This indication may include a limit switch, a magnet or contact reed relay, in the base 14 against which the arm assemblies, 16 and 18 rest in their relaxed position. Instead of a full release indicator, a mechanism could be added to the arm assemblies, 16 and 18, to prevent the application of force to the handles 30 and 32 until complete release has taken place (and the return to the relaxed position). For this purpose, a ratchet mechanism provided with discrete separations could be used. On the other hand, such mechanisms are commonly found in electrical wrinkling tools for loose terminals. It is possible to incorporate in the converter a mechanism for storing and releasing energy suddenly during the application of a downward force, applying a high-intensity, short-duration force to the chest instead of the application of a long-lasting force., as with the preferred embodiment. It is preferred that the device that rests on the upper part of a patient's chest be as light as possible. The reason for this is that after a patient's chest has been completely compressed, any weight resting on top of the chest will tend to resist decompression of the chest once the compression force has been removed. The reduction of this weight minimizes the degree of unwanted compression, during the release and decompression of the chest. The adhesive pad 500, shown in Figure 16, could contain an electrode which is electrically fixed to a conventionally known voltage generating device. The adhesive pad 500 could be used in combination with one or more electrodes 504 interposed along the length of the strap 506 or embedded in the board 508. These electrodes are used in a conventional manner to induce a current through the chest 510 and which is used to defibrillate the patient's heart. Any combination of two or more electrodes can be used to induce an electrical current to defibrillate the heart. The electrodes 504 may be interposed in multiple positions along the length of the belt 506, or in the board 508, but preferably there will be a minimum of one electrode in the base 512 (such as the adhesive pad 500 which functions as an electrode ) in addition to at least one other electrode 504. The reason why it is desirable to have an electrode at least at base 512, is that the greater extent of chest compression 510, the distance between the anterior and posterior exterior surfaces , of chest 510, will be at a minimum value, and base 512 will be positioned closer to the heart than at any other point in the entire compression / decompression cycle. At this stage of events, there is a minimum resistance to the current flow that gives the maximum flow of current through the heart with the least chance of injuring the tissue 510 of the patient's chest. The electrodes 504 may be positioned not only circumferentially around the chest 510, but may also be positioned in the same circumferential location but with various longitudinal separations. It is preferred that there be a means adapted to limit the travel of the assemblies 416 and 418 shown in Figure 13, in order to allow only the assemblies 416 and 418 to move in equal amounts with respect to the base. It is undesirable that one set moves to one side to a greater degree than the other set, as this causes an imbalance in the application of force, which can be the cause of injury to the patient. The injury occurs when a greater force is applied on one edge of the base than on the opposite edge. This can happen if one of both sets, 416 and 418, moves a substantially greater distance than the other set. A means to limit its relative movement is a spike or pin in slits aligned in the arms. Another is a gear mechanism connected to both sets, 416 and 418.

While certain preferred embodiments of the present invention have been disclosed in detail; it should be understood that there are several modifications that can be adopted without departing from the spirit of the present invention or from the scope of the following claims.

Claims (40)

1. An apparatus for increasing the flow of blood in a patient, characterized in that the apparatus comprises: (a) a base, contoured to settle close to a central region of a patient's chest; (b) a manual actuator; (c) a substantially inelastic strap, to be passed around the chest; and (d) a force converter, mounted on the base, connected to the actuator and having connectors for the belt, for connecting to the first and second opposite ends of the belt, intended to convert a force manually applied to the actuator and directed towards the chest, in a resultant that compresses the chest directed through the base towards the chest and in the resultant that adjust the strap, applied to the connectors for the strap and directed tangentially with respect to the chest.

2. - An apparatus according to claim 1, characterized in that the second manual actuator comprises manually grasps first and second handles.

3. - An apparatus according to claim 2, characterized in that the converter comprises: (a) a first arm, which has a handle end to which the first handle is mounted and which has an opposite end, for the belt, to which it fixes a first end of the belt, said first arm being pivotably mounted on the base in a fulcrum for the first arm located in an intermediate position between the end of the handle and the end of the belt; and (b) a second arm, having an end for the handle to which the second handle is mounted and having an opposite end, for the belt, to which a second end of the belt is attached, said second arm being mounted pivotably in the base in a fulcrum for the second arm located in an intermediate position between the end of the handle and the end of the belt.

4. - An apparatus according to claim 2, characterized in that the converter comprises: (a) a first set, having a pair of arms spaced apart and parallel to one another, rigidly connected at ends of the handle by the first handle, the arms being rigidly connected to opposite ends of the belt by a first strut, and the arms being pivotably mounted on the base of a fulcrum for the first set, located in an intermediate position between the handle and the ends of the belt; and (b) a second assembly, having a pair of arms spaced apart and parallel to each other, rigidly connected at handle ends by the second handle, the arms being rigidly connected to opposite ends of the strap by a second strut, and the arms mounted pivotably on the base in a fulcrum for the second assembly, located in an intermediate position between the handle and the ends of the belt.

5. - An apparatus according to claim 4, characterized in that one of the arms of the pair of the first set and one of the arms of the pair of the second set, are mounted on one side of the base, and the other arm of the pair of the first set and the other arm of the pair of the second set are mounted on a side opposite the base.

6. - An apparatus according to claim 5, characterized in that the fulcrums of the assemblies or assemblies coincide on a pivot pin that extends through all the arms of the assemblies and through the base.

7. An apparatus according to claim 6, characterized in that the ends of the belt and the ends of the handles of the arms, have longitudinal axes, and the end axis for the belt, of each arm is transverse with respect to the end axis of the arm. handle, of the same arm.

8. - An apparatus according to claim 7, characterized in that an angle of approximately 120 degrees is formed between the end axis of the belt of each arm, and the end pair of the handle, of the same arm.

9. - An apparatus according to claim 4, characterized in that the first end of the belt is shaped to be fixed to the end for the belt, of at least one arm of each set, and the second end of the belt is shaped to be fixed to the belt. end for the belt, of at least one arm of each set.

10. - An apparatus according to claim 4, characterized in that the first end of the belt is shaped to be fixed to the first strut, and the second end of the belt is shaped to be fixed to the second strut.

11. - An apparatus according to claim 10, characterized in that it also comprises fasteners mounted to the ends of the belt.

12. - An apparatus according to claim 11, characterized in that the fasteners comprise hooks and loops.

13. - An apparatus according to claim 11, characterized in that it also comprises indicators or legends printed on a surface of the belt corresponding to a length of each end of the belt.

14. - An apparatus according to claim 13, characterized in that the printed indicators or legends are bands of colors oriented transversely with respect to a longitudinal axis of the belt.

15. - An apparatus according to claim 5, characterized in that a pair of stroke limiting bars is mounted pivotably on the pair of arms of the first set, between the fulcrums and the handle ends, of each of the arms, which extend so as to have a sliding fastening with the pair of arms of the second assembly, each of said stroke limiting bars extending between arms mounted on the same end of the base, in order to limit the relative displacement of the arms fixed.

16. - An apparatus according to claim 15, characterized in that the stroke limiting bars are fixed slidably, adjustable to the pair of arms of the second set, in order to adjust the limitation of the strokes.

17. - An apparatus according to claim 4, characterized in that it also comprises a rigid, substantially flat board, to which the belt is fixed.

18. - An apparatus according to claim 17, characterized in that the board has two parallel spaced slits through which the belt extends.

19. - An apparatus according to claim 18, characterized in that the board has a raised portion, integrated with a flat portion, shaped to receive and support the neck of a patient above the flat portion.

20. - An apparatus according to claim 19, characterized in that it further comprises a gas container, pressurized, a hose and a breathing mask, housed inside the board, below said elevated portion.

21. - An apparatus according to claim 20, characterized in that it further comprises a sensor or force detector on a base surface that makes contact with the chest, and a force indicator mounted on the base.

22. - An apparatus according to claim 21, characterized in that it also comprises a signal generator, mounted on the base, to produce periodic signals.

23. - A method for treating patients, characterized in that it comprises: (a) seating the base of a blood flow increasing device, on a patient's chest, near each central region of the chest; (b) passing a strap around the patient's chest; (c) securing said first and second opposite ends of the strap to the apparatus; (d) applying a force, directed towards the chest, to a manual actuator mounted on a converter, said converter being connected to the base and to the belt, configured to convert the force into a resultant that compresses the chest, directed toward the chest , and in resultants that adjust the strap, directed tangentially with respect to the chest.

24. - A method according to claim 23, characterized in that the application of the force further comprises grasping a pair of manually accessible handles and applying a force having a component directed toward the chest.

25. - An apparatus for increasing blood flow in a patient, characterized in that the apparatus comprises: (a) a base, configured to settle close to a central region of a patient's chest; (b) an actuator; (c) a belt, substantially inelastic, configured to be passed around the chest; and (d) a force converter, mounted on the base, connected to the actuator and having connectors for the belt, to connect with the opposite ends of the belt, intended to convert a force applied by the actuator, into a resultant that compresses the chest directed through the base toward the chest, and in resulting belt adjusters directed tangentially to the chest.

26. - An apparatus according to claim 25, characterized in that the actuator comprises a primary motor.

27. - An apparatus according to claim 26, characterized in that the force converter comprises: (a) a first arm, having a handle end and an opposite end for the strap, to which a first end of the strap is attached. said first arm being pivotally mounted on the base in a fulcrum for the first arm, located in an intermediate position between the end for the handle and the end of the belt; and (b) a second arm, having a handle end to which the second handle is mounted and having a second, opposite end for the strap, to which a second end of the strap is attached, said second arm being , pivotally mounted on the base in a fulcrum for the second arm located in an intermediate position between the end for the handle and the end of the strap.

28. - An apparatus according to claim 26, characterized in that the converter means comprises: (a) a first set, having a pair of arms spaced apart and parallel to one another, rigidly connected at handle ends by the first handle, the arms being rigidly connected to opposite ends for the belt by a first strut, and the arms being pivotably mounted on the base in a fulcrum for the first set located at an intermediate position between the ends for the handle and for the belt; and (b) a second assembly, having a pair of arms spaced apart and parallel to each other, rigidly connected at handle ends by the second handle, the arms being rigidly connected to opposite ends for the belt by a second strut, and the arms mounted pivotably on the base in a fulcrum for the second assembly, located in an intermediate position between the ends for the handle and for the belt.

29. - An apparatus according to claim 28, characterized in that one of the arms of the pair of the first set and one of the arms of the pair of the second set are mounted on one side of the base, and the other arm of the pair of the first set and the other arm of the pair of the second set are mounted on an opposite side of the base.

30. - An apparatus according to claim 29, characterized in that the fulcrums of the assemblies coincide on a pivot pin that extends through all the arms of the assemblies and through the base.

31. - An apparatus according to claim 6, characterized in that the arms are curved.

32. - An apparatus according to claim 5, characterized in that it also comprises at least one pair of opposing shoulders formed in a pair of opposite arms, having formed one of the shoulders, in each arm, in order to form a gap between the shoulders confronted within which a stop pin extends, in order to limit the relative displacement of the opposing arms.

33. - An apparatus according to claim 5, characterized in that it further comprises: (a) three shoulders, formed in each of two opposite arms, forming three clearances of different lengths between three pairs of opposing shoulders; (b) a stud, mounted on the base and having three holes formed therethrough, each hole corresponding to a clearance; and (d) a stopping pin, which extends from the insertion in one of the holes towards the inside of one of the clearances, adapted to limit in an adjustable manner the relative displacement of the opposite arms.

34. - An apparatus according to claim 4, characterized in that it also comprises a means mounted on a surface of the base that comes into contact with the chest, to affix the surface that makes contact with the chest, chest.

35. - An apparatus according to claim 34, characterized in that the means for adhering comprises a suction cup.

36. - An apparatus according to claim 34, characterized in that the means for adhering comprises an adhesive.

37. - An apparatus according to claim 1, characterized in that it further comprises a pair of separate electrodes mounted to the apparatus for contacting two outer surfaces of the chest.

38. - An apparatus according to claim 37, characterized in that a first electrode is mounted on an outer surface of the base that makes contact with the chest, and there is a second electrode mounted on a surface of the apparatus that makes contact with the chest, which is separated from the first electrode.

39. - An apparatus according to claim 38, characterized in that the second electrode is mounted on the belt.

40. - An apparatus according to claim 39, characterized in that it further comprises a plurality of electrodes interposed along a longitudinal axis of the belt.