Patent Application
20100198118
The disclosure relates to cardiac massage devices (CMDs), and to methods of operating such devices. CMDs may be used for performing external cardiac massage (ECM). Hence, the disclosure also relates to methods of performing ECM with CMDs.
With regard to some belt-type devices such as thorax circumferences change based cardiac massage devices, as may be embodied in belt-shortening type devices and cuff-tightening based devices, it may be noted that any of these principals may use transfer of driver energy into linear motion that ultimately changes the length of material\band\strap\cuff in contact with the thorax. The reduction of amount of material extending, end-to-end from the device results in pressure applied on the thorax's circumferences, and thus for the cardiac massage. Generally, the mechanisms for applying force to the belt(s) may employ a spool (in the case of a belt) or a gear to the circumference changing element (belt, cuff). These types of force transfer are inefficient by nature as the force is not transferred to the thorax directly, but rather goes via intermediate mediums\hardware parts (like the spool) a that add friction and residual forces.
The conventional approach to the inefficiency of force-transfer (problem) is to use a powerful motor. To provide the needed energy for said motor, a strong battery is required. For example, in some devices a 2.5 kg battery may be required for 20-30 min of operation. This has some drawbacks: it may increase cost (the power source is expensive), it may make the device heavy (less portable), and it may impose larger physical dimensions on the device.
Cardiac massage refers to an intermittent compression of the heart by pressure applied over the sternum (closed, or external cardiac massage) or directly to the heart through an opening in the chest wall (open, or internal cardiac massage). Cardiac massage may be performed to reinstate and maintain blood circulation. In the main hereinafter, external (or closed) cardiac massage (ECM), and devices for performing same are discussed.
Cardiopulmonary resuscitation (CPR) is an emergency medical procedure for a victim of cardiac arrest or, in some circumstances, respiratory arrest. CPR may be performed in hospitals, or in the community by laypersons or by emergency response professionals.
CPR, when applied immediately after cardiac arrest, can often save cardiac arrest patients' lives. CPR may require that the person (caregiver, rescuer) providing chest compressions repetitively pushes down on the sternum of the patient (victim) at a rate of 80 to 100 compressions per minute. The compression of the sternum in CPR treatment is referred to as “cardiac massaging” thus, a device for “cardiac massaging” may be referred to as a “CMD”. CPR may be applied anywhere, wherever the cardiac arrest patient is stricken. Out-of-doors, away from medical facilities, it may be accomplished by either poorly (or inadequately) trained bystanders, or by highly trained paramedics and ambulance personnel.
Cardiopulmonary resuscitation (CPR) is a well-known and valuable life-saving method of first aid. CPR is used to resuscitate people who have suffered from cardiac arrest after suffering a heart attack, electric shock, chest injury and other causes for cardiac arrest or disorder. During cardiac arrest, the heart stops pumping blood, and a person suffering cardiac arrest will soon suffer brain damage from lack of blood supply to the brain. Thus, CPR requires repetitive chest compression to mechanically squeeze the heart and the thoracic cavity to pump blood through the body. CPR is usually followed by defibrillation that is intended to reset heart fibrillation. Very often, the patient is not breathing, and mouth to mouth artificial respiration or a bag valve mask is used to supply air to the lungs while the chest compression pumps blood through the body.
For many years, CPR has consisted of the combination of artificial blood circulation with artificial respiration—that is, chest compressions and lung ventilation. Recently however, the American Heart Association and the European Resuscitation Council endorsed the effectiveness of chest compressions alone—without artificial respiration—for adult victims who collapse suddenly in cardiac arrest. (Hence, in the absence of artificial respiration, “CPR” is somewhat of a misnomer, since there is no specific “P”ulmonary component.) specific effort to supplant breathing.) CPR is generally continued, usually in the presence of advanced life support, until the patient regains a heart beat (called “return of spontaneous circulation” or “ROSC”), or is declared dead.
CPR is unlikely to restart the heart, but rather its purpose is to maintain a flow of oxygenated blood to the brain and the heart, thereby delaying tissue death and extending the brief window of opportunity for a successful resuscitation without permanent brain damage. Advanced life support (most commonly defibrillation), is usually needed to restart the heart.
Traditional manual CPR usually refers to performing mouth-to-mouth rescue breathing, and performing manual chest compressions. Chest compressions may be performed by the rescuer placing the heel of his (or her) hand in the middle of the victim's chest, with the other hand on top of the first hand with fingers interlaced. Then, compressing the chest about 1½ to 2 inches (4-5 cm). Then allowing the chest to completely recoil before the next compression. Compressing the chest at a rate equal to 100/minute, and performing 30 compressions at this rate. Pausing to perform rescue breaths, then repeating chest compression followed by rescue breaths, until the victim may resume breathing or until help arrives.
Compression-only CPR, also known as cardiocerebral resuscitation (CCR), is simply chest compressions without artificial respiration. The method of delivering chest compressions remains the same as with CPR, as does the rate (100 per minute), but the rescuer delivers only the compression element which keeps the bloodflow moving without the interruption caused by mouth-to-mouth (MTM) respiration. It has been reported that the use of compression only delivery increases the chances of lay person delivering CPR.
Devices
Some devices are available in order to help facilitate rescuers in getting the chest compressions completed correctly, during delivering CPR. The simplest of these is a timing device, such as a metronome, which may assist the rescuer in getting the correct rate for chest compressions. A number of manual assist devices have been developed to help improve CPR technique. These devices may be placed on top of the victim's chest, with the rescuers hands going over the device, and may provide a display or audio feedback giving information on depth, force or rate. Alternatively, these manual assist devices may be in a wearable format such as a glove. As well as use during actual CPR on a cardiac arrest victim, which relies on the rescuer carrying the device with them, these devices can also be used as part of training programs to improve basic skills in performing correct chest compressions.
Automatic cardiac massage devices (CMDs) are also available for performing chest compressions on the victim. The chest compression device may be any device suitable for compressing the chest of a patient, such as pneumatic, hydraulic, or electric actuated pistons, belts, straps, and other.
There are a number of different types of automatic CMDs, including, for example
Note that the plunger type and the first two mentioned band-types include a mechanism having a plunger for performing chest compressions. The “plunger” may be referred to by other names, such as “sternum compressing element”, “depressor means” , “displacement means”, and the like.
A chest compression device is known that may be fixed to the patient's chest/skin by means of fastening devices such as tape or by vacuum, or it can be merely in contact with the chest without being fastened to the chest. The chest compression device can be designed to cause the chest to expand, that is to perform an active lifting of the chest, or to allow the chest to expand freely. The chest compression device typically comprises or is connected to a support in order to maintain a substantially constant positioning of the chest compression device on the patient's chest. A substantially constant positioning of the chest compression device on the patient's chest is important in order to obtain the necessary quality of the compressions and for safety reasons.
An exemplary chest compression system (automatic CMD) may comprise a chest compression device (sternum compressing element), and a signal processor (electronic controller) connected to the chest compression device for providing control signals to the chest compression device. Measuring (sensing) devices may be provided for measuring characteristics of the resuscitation process, and the signal processor may be adapted to process input signals from the measuring devices. The measuring device(s) may be any sensors or other measuring devices suitable for measuring characteristics of the resuscitation process, and other relevant information regarding CPR in the system and/or in the patient: Such sensors/measuring devices are for example force sensors and/or depth sensors for measuring force/depth exerted/traveled by the compression device, compression counters, compression frequency counters, blood flow sensors for monitoring the blood flow of the patient, ventilation sensors for monitoring the ventilation flow, volume, and/or time interval of patient ventilation, impedance measuring means for measuring the impedance of the chest and thus give an indication of the ventilation of the patient, electrocardiogram (ECG) device, tilt sensors for measuring the angle of the patient (whether the patient is lying, sitting/standing), position detectors for detecting the positioning and/or change of positioning of the chest compression means, battery power measurement means, internal motor temperature measuring means, and the like. The results from the measuring devices may be used to provide information to the users and/or as feedback to the processor for adjusting/changing the control signals to the compression device.
In ECM, firm pressure may be exerted on the lower half of the sternum, in order to compress the heart and major vessels between the sternum and the spine, resulting in cardiac output. The pressure needed vary from about 36 kgs to 55 kgs and the sternum should be depressed about 3.5 to 5 cm, varying from patient to patient. The cycle is repeated uniformly and smoothly at about 40-100 strokes per minute, allowing approximately equal time for depression and relaxation of the sternum.
A depressor means may be adapted to be secured against the sternum of a patient and to exert pressure thereon. Contact with the sternum may be by way of a reciprocating block secured in place by support means. The support means may include a flexible band connected to the reciprocating block for fastening around the chest of a patient and sprung support legs on either side of the block for additional stability and to enhance residual pressure on the sternum. Alternatively, the support means may comprise a rigid adjustable frame.
Recently, a device names LUCAS has been made commercially available. LUCAS is a gas-driven CPR device providing automatic chest compression and active decompression. It is portable and works during transport, both on stretchers and in ambulances. See “Evaluation of LUCAS, a new device for automatic mechanical compression and active decompression resuscitation”, Elsevier, Resuscitation 55 (2002) 285-289, incorporated in its entirety by reference herein.
The Zoll® AutoPulse® Resuscitation System Model 100 is a band-type device that has its own “soft carry” stretcher (platform). Bands are strapped across the patient's chest. The device automatically adjusts the bands to the patient's chest, and performs the chest compressions. See AutoPulse® User Guide, incorporated in its entirety by reference herein. The basic operating characteristics of the device are:
Some problems associated with manual ECM may include fatigue to the operator, variation in the rate, force and duration of compressions, and limited facility for transportation and movement of the patient while ECM is being carried out. Further, inexperienced operators often cause injuries to the patient such as fractures to the ribs and sternum, lung damage, laceration to the liver or costochondral separation.
A number of mechanical devices have been developed with a view to overcoming the problems of manual external cardiac massage. However, these devices display a number of deficiencies. For example, there may be a tendency for the sternum depressor element (or compression member) of the device to shift position on the sternum which may lead to greater instances of rib and sternal fractures, liver laceration, lung damage and costochondral separation.
The compression member of an ECM device may have a contact pad which is formed of a resiliently deformable material to spread the load applied to the patient's chest, and thereby reduce the risk of injury thereto.
Force, displacement and frequency are typical operating parameters for sternum compressing elements of ECM devices, exemplary ones of which may be:
Note that force is substantially related to displacement, depending on, for example, the elasticity of the medium being acted upon.
As reported in “Compression force-depth relationship during out-of-hospital cardiopulmonary resuscitation”, Elsevier, Resuscitation (2007) 72, 364-370, incorporated in its entirety by reference herein, for chest compressions to be efficient, they must be executed with a force sufficient to produce adequate sternal displacement, and there may be a strong non-linear relationship between the force of compression and the depth achieved. The difficulty of an adult rescuer providing chest compressions with the force necessary to displace the sternum to an adequate dept is discussed. The elastic properties of the human chest during chest compressions, and the force the force needed to induce a given depth of sternal deflection is discussed. Variations in chest wall elasticity between individuals is discussed, as well as how chest elasticity may change over time
Resuscitation systems are known, for example, comprising a chest compression device to repeatedly compress the chest of a patient and thereafter causing or allowing the chest to expand, a defibrillator to apply electric impulses to the heart, measuring devices for measuring characteristics of the resuscitation process, and a signal processor for controlling operation of the chest compression device and/or the defibrillator. The defibrillator may be an integrated or external device working in a master/slave relationship with the remaining system. The defibrillator may be controlled by predetermined characteristics of the resuscitation process, which may include predetermined and/or measured characteristics.
Band-Type External Cardiac Massage (ECM) devices are known wherein pressure is transmitted from the pressure source to the sternum via a depressor means in a rhythmic fashion gradually increasing over time to a maximum, then decreasing at a like rate while maintaining a minimum residual pressure on the sternum. Pressure may be transmitted from said pressure source to the sternum in a cyclic fashion gradually increasing over time in the first half of a cycle to a maximum pressure and decreasing at a like rate over the second half of a cycle. The pressure may not decrease to zero, a minimum residual pressure may be maintained. This may result in an effective compression of the heart with minimum risk of physical injury to a patient.
Plunger-type External Cardiac Massage (ECM) devices are known wherein an adjustable time controls the operation of the displacement means, for a fixed rate, such as 20 compressions per minute.
Plunger-type External Cardiac Massage (ECM), high impulse CPR devices are known wherein a waveform (associated with movement of the plunger) more closely resembles a square wave, or impulse, rather than a sinusoidal form. This may result in a fast rise in the chest compression stroke, and consequently applying a greater amount of energy to the patient during the systolic phase, which may improved perfusion in the cardiovascular system of the patient.
Various external cardiac massage (ECM) devices are known, such as (but not limited to), for example:
A response to cardiac arrest generally comprises four phases:
Bystander CPR occurs, if at all, within the first few minutes after cardiac arrest. Basic Cardiac Life Support (BCLS) may be provided by first responders who arrive on scene, in average 10 minutes after being dispatched to the scene. First responders include ambulance personnel emergency medical technicians, firemen and police. Though defibrillation and drug therapy is often successful in reviving and sustaining the patient, CPR is often ineffective even when performed by well-trained first responders and ACLS personnel because chest compression becomes ineffective when the providers become fatigued due to the difficulty to maintain the rate and compressions force for longer than few minutes. Thus, the initiation of an effective and continuous CPR before arrival of first responders is critical to successful resuscitation. Moreover, the assistance of an automatic mechanical chest compression device during the BCLS and ACLS stages is needed to perform and maintain a continuous and effective resuscitation.
This summary section of the patent application is intended to provide an overview of the subject matter disclosed herein, in a form lengthier than an “abstract”, and should not be construed as limiting the disclosure to any features described in this summary section.
It may be an object of the disclosure to provide improved techniques for performing external cardiac massage (ECM), using cardiac massage devices (CMDs). This may include the devices, features of such devices, systems incorporating such devices, and methods of operating the devices.
It may be an object of the disclosure to provide a cardiac-massage-device (CMD) that is compact, light weight and portable, is efficient in providing external cardiac compressions, easy to operate and simple to store, carry along and transport in public as well as domestic premises.
It may be an object of the disclosure to provide a cardiac-massage-device (CMD) that can be adjusted to the physiological parameters of any individual and a plunger that applies the required force and depth of compressions suitable to the specific elasticity of any given patient's thorax.
It may be an object of the invention to improve the structure and operation of belt-type ECM devices.
It may be an object of the invention to modify and/or augment force delivered by belt-type ECM devices.
It may be an object of the invention to improving or optimizing force delivery in thorax circumferences change based cardiac massage devices, as may be embodied in belt-shortening type devices and cuff-tightening based devices.
According to an embodiment of the disclosure, an external cardiac massage (ECM) device may comprise: a sternum compressing element adapted to be positioned on a patient's chest for massaging the patient's heart; a mechanism for imparting force to the sternum compressing element; and a force booster, operatively disposed between the mechanism for imparting force and the sternum compressing element. The force booster may comprise a compression-type spring, and the spring may be pre-compressed. One or more force modifying elements may be disposed in a drive train from the mechanism for imparting force to the sternum compressing element. The force booster may comprise an energy-accumulation mechanism. The force booster may comprise a force-modifying element. A force-modifying element may be adapted to be used in conjunction with the force-boosting element. The device may further comprise an electronic controller for controlling movement of the sternum compressing element. The sternum compressing element may comprise a compression band adapted to at least partially encircles a patient's torso. The device may further comprise a block of material adapted to be portion of the compression band passing over the patient's chest, and the patient's chest, and the block of material may comprise a compression pad, or a viscous fluid, or a non-Newtonian fluid. The mechanism for imparting force may be selected from the group consisting of rotary motor, linear motor, solenoid, and pneumatic piston.
The ECM device may further comprise: a backboard adapted to support the patient in a supine position and for housing various mechanical elements and mechanisms of the device.
The sternum compressing element may comprise a belt. A force-altering element may be disposed between a portion of the belt passing over the patient's chest and the patient' chest.
The force-altering element may comprise a shock absorber. The force-altering element may be is adapted to dampen force in at least one direction. The force-altering element may be adapted to store energy in at least one direction. The device may further comprise a drive spindle for intermittently tightening the belt. A torsion spring may be disposed on the drive spindle. At least a portion of the belt may comprise a pneumatic tube portion. The mechanism for imparting force may comprise a pump providing pressurized air or fluid to a pneumatic portion of the belt. The device may further comprise a force-modifying element disposed in fluid communication between the pump and the pneumatic portion of the belt, and said force-modifying element may be selected from the group consisting of valves, petcocks, and dampers.
According to an embodiment of the disclosure, an external cardiac massage (ECM) device may comprise: a belt or cuff at least partially encircling a patient's chest: a mechanism for in intermittently tightening the belt; a plunger package disposed between the belt and the patient's chest, said plunger package comprising at least one of: a second mechanism for imparting force to the plunger; a plunger acted upon by the second mechanism for imparting force; and a position/angle altering mechanism adapted to alter a direction or position of force applied by the plunger to the patient's chest.
According to an embodiment of the disclosure, an external cardiac massage (ECM) device may comprise: a belt or cuff at least partially encircling a patient's chest: a mechanism for in intermittently tightening the belt or cuff; a pneumatic tube disposed between the belt and the patient's chest; and a mechanism for intermittently pressurizing the pneumatic tube.
According to an embodiment of the disclosure, an external cardiac massage (ECM) device may comprise: a sternum compressing element adapted to be positioned over a patient's thorax for externally massaging the patient's heart; a mechanism for imparting force to the sternum compressing element; a controller for controlling movement of the sternum compressing element; and memory to record and retain a coherent (usually time-based) record (data) of device operation and patient condition. The memory may be selected from the group consisting of disk, Flash Memory and compact disc (CD). The following terms may be used in the descriptions set forth herein:
Examples illustrative of embodiments of the disclosure are described below with reference to figures attached hereto. In the figures, identical structures, elements or parts that appear in more than one figure are generally labeled with a same numeral in all the figures in which they appear. Dimensions of components and features shown in the figures are generally chosen for convenience and clarity of presentation and are not necessarily shown to scale. The figures (FIGs.) are listed below.
Many of the figures presented are in the form of schematic illustrations and, as such, certain elements may be drawn greatly simplified or not-to-scale, for illustrative clarity. The figures are not intended to be production drawings.
In the following description, various aspects of techniques for external cardiac massage (ECM) will be described. For the purpose of explanation, specific configurations and details are set forth in order to provide a thorough understanding of the techniques. However, it will also be apparent to one skilled in the art that the techniques may be practiced without specific details being presented herein. Furthermore, well-known features may be omitted or simplified in order not to obscure the description(s) of the techniques.
Although various features of the disclosure may be described in the context of a single embodiment, the features may also be provided separately or in any suitable combination. Conversely, although the disclosure may be described herein in the context of separate embodiments for clarity, the disclosure may also be implemented in a single embodiment. Furthermore, it should be understood that the disclosure can be carried out or practiced in various ways, and that the disclosure can be implemented in embodiments other than the exemplary ones described herein below. The descriptions, examples, methods and materials presented in the in the description, as well as in the claims, should not be construed as limiting, but rather as illustrative.
Terms for indicating relative direction or location, such as “up” and “down”, “top” and “bottom”, “horizontal” and “vertical”, “higher” and “lower”, and the like, may also be used, without limitation.
An Example of a Cardiac Massage Device (CMD)
Generally, a cardiac massage device (CMD) may comprise a cardiac massaging element for providing controlled compression of a thorax of a patient; and a controller for controlling the compression based on characteristics of the patient.
The CMD may comprise some or all of the following elements:
The structure may comprise a strain release mechanism for unloading overload applied by the plunger on the thorax of the patient.
The CMD may comprise a sensor for determining the elasticity of the thorax of the patient, and the controller may be adapted for adjusting the operation of the driver of the plunger or adjusting the travel of the plunger, to comply with the elasticity of the thorax of the patient.
The CMD may comprise one or more sensors, selected from a group of sensors comprising: compression sensors, load sensors, strain sensors, pulse sensors, blood pressure sensors, ECG sensors, CO2 sensors and oximetry sensors.
The plunger may comprise at least one energy storing element, which may comprise at least one preloaded spring.
The CMD may comprise a microphone, and a speaker for providing audible guidance to a caregiver.
The CMD may comprise a communication module for communication with a remote location.
The CMD may comprise a memory for storing and retrieving operation data of the device.
The CMD may comprise a defibrillator. The CMD may be adapted to communicate with a separate cardiac defibrillator.
The weight of the CMD may be no more than 3 kilograms and, in a compact (folded, not deployed) state, the CMD may have a volume of no more than one thousand cubic centimeters.
Generally, a compact, light weight (such as less than 5 kg) and portable automatic mechanical CMD is provided. When a situation arises in which a person is in cardiac arrest the device may be deployed, and used. First, a preliminary deployment of the device may be done, followed by a personal fitting of the device to the patient. Thus, the device is fitted and affixed to the patient by a caregiver (the operator of the device, or “rescuer”). Upon being affixed to the patient the device operation may be initiated by the caregiver. The device is simple and quick to adjust to the anatomical build of a patient in need of CPR and is simple to operate by people who may have had no previous experience.
The CMD may comprise a rigid or a semi-rigid foldable structure that is adapted to transform from a folded state to a deployed state. In its folded state, the device is compact for storage and easy to carry along. The folded device may be pocket-sized, and may be suitable to be carried in a pocket or on the waist belt of a caregiver.
The CMD may be further adapted to facilitate a size adaptation of its structure in its deployed state to the anatomical build of the patient. Such adaptation may be performed in various ways. For example, the device's structure may comprise longitudinally extendable elements that are capable to extend or to be minimized, such as but not necessarily telescopic rods that allow the caregiver to fit the device size in a deployed state to a specific patient.
The CMD may be mounted on the patient from his (or her) left-hand or right hand side. Or, the CMD may be mounted on the patient from the shoulders downward towards the thorax.
The CMD may be partially or fully dismantled for compact storage, and may be assembled upon use.
The CMD may include a mechanical plunger driven by a motor such as an electric power-packed motor (with one or more batteries serving as its power source), optionally, with a planetary gear. The motor may be a DC (direct current) motor, and may be integrated in the device structure.
The motor may be of a small size and light weight. A small size and light weight motor is typically characterized by a lower torque. Since a motor force is calculated as: force=torque×rpm (round per minute), the initiation of an exemplary 50kg force for providing effective CPR, a high rpm (revolutions per minute) motor may be used in order to compensate for the lower torque. Thus, the motor may be a high speed motor with at least 10,000 rpm.
The plunger (“sternum compressing element”) is driven by the motor (“mechanism for imparting force”), to thereby perform cardiopulmonary chest compressions. The motor may forces the plunger, via a crankshaft, to move in a repetitive predetermined vertical travel course of compression and release of the thorax. The motion is between two opposite positions of the plunger may be in a range of 3 to 8 cm. In order to compress the thorax approximately 3 to 8 cm deep (which is typically the desired compression depth) an approximate typical force load of approximately 50 kg on the thorax may be required.
In order to be able to extract the required force (such as 50 kg) for compression, using a compact motor, an energy storing element such as preloaded spring (or springs), a memory flex material, pneumatic or hydraulic piston that is adapted to function as a spring, or any other energy storing material known in the art that is suitable for the purposes of the present invention, is used to assist the motor in forcing the plunger movement (illustrated in
The device may comprise a control unit that controls the motor and thus the motions of the plunger. The control unit may comprise an electronic controller and control circuitry adapted to monitor and govern the rate of compression/release cycles, the compression force and any other relevant parameter to the performance of the CPR procedure. For example, information concerning the plunger's motion may be obtained from sensors connected to the plunger mechanism or to the structure (hereinafter: “compression indication sensors”). The compression indication sensors may be adapted to provide indications regarding the plunger motion or the load applied by the plunger. Said indications may be used to monitor and control the compression load on the patient's thorax. Alternately, said indication may be retrieved from an encoder (sensor) incorporated in the motor.
The CMD of the present invention may further comprise a “life-signs” sensor or sensors, for example a pulse sensor, an ECG monitoring module and/or blood pressure, a CO2 sensor and an oximetry sensor. The controller may process data fed to the controller from said “life-signs” sensors applied to a CPR patient, and direct commands to the driving mechanism to initiate the automated CPR or advise the caregiver to initiate CPR.
The term “plunger driving mechanism” may be used herein to refer to the mechanical mechanism that enables the motion and stability of motion of the plunger.
The control unit may be further adapted to operate a man-machine interface. The man-machine interface may comprise at least an operation “ON”/“OFF ” button, an LCD (liquid crystal display) panel, or an LED display, a speaker for audio feedback or guidance and a microphone. For example, the speaker and microphone may be used by an untrained caregiver to communicate with medical professionals to thereby assist the caregiver in dealing with a cardiac arrest case. The microphone may also be used for recording scene ambient sounds for documenting the process of CPR events.
The control unit may be further adapted to govern the device state, for example battery state, load on the motor, pre-tensioning of the plunger against the patient's thorax, state of a communication link with a remote location and the adequate deployment of the device.
The CMD may also include a memory for storing data relating to the operation of the device or data relating to the patient. This data may include, for example, data concerning the motor operation, the plunger travel, the plunger load on the patient's thorax, the device state, pulse rate of the patient, blood pressure of the patient, and other data.
When performing a CPR procedure, the CMD may perform one or more of the following exemplary actions (through control unit commands):
An exemplary plunger type CMD will now be described, in greater detail, with respect to
CMD 10 may be constructed of: a foldable and rigid support-structure 12, an electric motor 14 incorporated into support-structure 12 and a plate-plunger 38 connected to motor 14 by a driving mechanism such as a crankshaft 18. Optionally, one or more lifesigns sensors (not shown) are connected to a control unit 20 which is built into or integrated with, support-structure 12.
The support-structure 12 may be composed of three elements: a length adjustable base-element 19, a height-adjustable-element 17 and a length-adjustable plunger-carrying element 15. Each of the three elements may be composed of two two-parallel-bars-units bridged at their end by a perpendicular bar (each unit referred from herein after as “TPBU”), made of light yet strong and rigid material or materials such as aluminum, titanium, sturdy plastics, composite materials and the like. By sliding one of the TPBU over the other TPBU a desired length of each of the three elements of supporting structure 12 may be determined. A suitable latching mechanism (not shown) may enable reversible adjustments and fixing-in-place desired lengths of the three elements of support structure 12 in accordance with the anatomical build of a CPR treated person as demonstrated in
The plunger 38 may be, for example, a 10 cm in diameter circular plate made of a substantially rigid material and covered by a soft, cushioning and biocompatible material, so as minimize harming the treated CPR patient. The plunger 38 can also be constructed in various shapes (not necessarily round) and have various diameters. The plunger 38 may be formed as an integral part of the crankshaft 18 or connected directly to crankshaft.
When the device 10 is in a deployed state, height-adjustment-element 17 is connected at one end at an angle (typically, but not limited to, 90 degrees) to base element 19 and at the other end to plunger-carrying-element 15 in an angle that positions element 15 in parallel to element 19. When in a deployed state, the base-element 19 is typically stretched (“length adjusted”), the length of element 17 may be adjusted to the anatomical build of the CPR patient (shown in
The three elements of supporting structure 12 are typically connected with one another when device 10 is in either a folded or deployed state. When in a folded state the three elements may be positioned substantially in parallel. Optionally, the elements may be designed so as to be disconnected from one another for the storage and maintenance of device 10.
The length-adjustable base element 19 may be made of a TPBU 22 that slides over fixed-in-place TPBU 24 (enabling the “stretching” of the element). TPBU 24 may be pivotally connected to hinge-unit 26. Hinge-unit 26 may be connected to another hinge-unit 28 by a height adjustable mechanism comprising fixed-in-place TPBU 30 that has a TPBU 32 sliding over it. Alternatively, TPBU 30 may be fixed-in-place and having TPBU 32 fit into TPBU 30, thus having TPBU 30 slide over TPBU 32. TPBU 30 and TPBU 32 together with hinge-units 26 and 28 may comprise height-adjustable element 17. Hinge-unit 28 may pivotally connect to a suspended element comprising TPBU 34 that has TPBU 36 sliding over it. Alternatively, TPBU 34 may slide over TPBU 36.
The electric motor 14 may be positioned between the bars of TPBU 36. At the end of TPBU 36, distanced from hinge-unit 28, the motor 14 is connected and has a rotational crankshaft 18 pivotally connected to plunger 38 by bar 37. A bridging plate 46 connects between bars of TPBU 36 and surrounds the motor 14, thereby stabilizing it in place.
The downward-facing side of plunger 38 may be provided with a pressure (“compression”) or load-sensor 62. The sensor 62 may measure and transmit data of the load of the plunger against the patient's thorax to the control unit 20. Load sensor 62 may be disposed in alternate locations of the CMD, for example, yet not limited to, arms 42, bar 37, TPBU 30 or other locations, either directly or indirectly, representing the load of the plunger on the thorax.
Plunger 38 may be connected to two parallel arms 42 which are connected to a base-plate 40. The plunger 38 may be connected to plunger carrying element 15 directly.
Base-plate 40 may be connected to bars 36, to stabilize the motor 14 in place. When the crankshaft 18 is rotated by the motor 14, the plunger 38 may linearly and vertically oscillate in a fixed course, causing a cyclic compression and releasing effect of the plunger on the patient's thorax. TPBU 34 and TPBU 36 together with hinge unit 28 and bridging-plate 46 comprise plunger-carrying element 15.
Hinge-units 26 and 28 enable the folding of TPBUs 22 and 24, and TPBUs 34 and 36 towards TPBUs 30 and 32, respectively.
As best viewed in
Optionally, pads 80 may be provided for attachment to the CPR treated person for measuring physiological parameters such as pulse or blood pressure. The data may be transmitted from the pads 80 via cords 76 and adaptor 73 to the control unit 20 for processing and commanding the activity of the plunger.
A plunger driving mechanism may utilize an energy-storing (accumulating) mechanism 44 to assist the motor in driving the plunger while applying compressions to the patient's thorax (or chest). In
For example, during the upstroke energy from the motor is stored, and during the downstroke, which is the chest compression stroke, the plunger benefits from the force supplied by the motor as augmented by the stored-up force supplied by the energy-accumulating elements.
Or, for example, the energy-accumulating elements 44 may comprise springs which are positioned vertically and connect between arms 42 and plate 46. The springs 44 may be made of material that maintains its resilience after many repeats of being compressed and relaxed. The arms 42 may be pivotally connected at one end to plate 40 and at the other end to plunger 38. The rotation of crankshaft 18 by the motor 14 drives plunger 38 in a fixed linear and vertically oscillation course (further illustrated in
Variations on the above may include:
A compression-sensor in the plunger (designated 62 in
In
Adjustment of the travel of the plunger to the elasticity of the patient's thorax may be obtained by deriving information regarding said elasticity from the load on the motor 14. Said load may be obtained by measuring the power consumption of power source 56 (shown in
At least one sensor may be used to monitor the load on the patient's thorax. When reaching a threshold value that may reflect a risk of an overload to the patient's thorax a safety mechanism may be initiated. An exemplary safety mechanism may be established by electronic means to thereby halt the operation of the motor and thereby to decease the compressions on the patient's thorax. An alternate safety mechanism may be established by incorporating in the CMD 10 a mechanical strain relief element that is adapted to mechanically release an overload. Such an element may be any mechanical strain relief element or mechanism that is known in the art.
Upon initiation of operation of the CMD 10, the controller 20 causes module 66 to provide activation/deactivation commands 66 to the motor 14, setting into motion or stopping the motion of plunger 38.
Optionally an LCD or an LED display 21, a speaker 68 for audio feedback or guidance and a microphone 70 are connected to control unit 20.
The control unit 20 may obtain information regarding the status of device 10, such as the battery state, the load on the motor, the pre-tensioning of the plunger against the patent's thorax and the adequate deployment of the device, and provides indication via STATUS INDICATOR 72. Said indications may be provided via DISPLAY 21.
The control unit 20 may be adapted to monitor and govern the rate of compressions, the compression/release cycle and any other parameter relevant to the performance of the CPR. Optionally data from “life signs” sensors (not shown in the figure) may be processed in controller 20, which may then activate an electronic defibrillation module 78 that actives, in turn, defibrillation pads 71 (
A Dynamically-Controlled Automatic External Cardiac Massage (ECM) Device
A Cardiac Massage Device (CMD) has been described hereinabove, and discloses:
The CMD includes a plunger-motor feed-back mechanism which enables the fine tuning of the compression of the plunger to be adjusted to the anatomical build of the patient being treated.
The variability of chest stiffness (or elasticity) during CPR which relates to the force applied and depth achieved, as well as variability over time has been noted. (See Elsevier paper, Resuscitation (2007) 72, 364-370, incorporated in its entirety by reference herein) and the apparent contradictory results that can be obtained between manual CPR where a human may vary pressure and depth versus a device-assisted CPR. Thus, a need exists in the industry, and this disclosure contemplates a solution for:
The device 600 comprises a base, or platform 602 which is disposed behind a patient's torso. The patient 650 is shown in a supine position, laying on his (or her) back. The patient's torso exerts its weight on the platform 602 to stabilize the device.
An elongated vertical support element 604 extends vertically upward (in the “z” axis) from a side (left, as shown) of the platform 602, past the patient's torso, to a point which is a distance above (and to the side of) the patient's torso. This is a “one-sided” device. Alternatively, there may be a similar vertical support element (not shown) on the other (right, as shown) of the patient's torso, resulting in a “two-sided” device.
An elongated horizontal arm 606 extends, such as in cantilever manner, from a top (as viewed) end of the support element 604, in the horizontal direction (in the “x” axis, as shown), towards the patient's other side (right, as viewed), so that at least a portion of the arm 606 is above the patient's chest. (In the alternative construction with vertical support elements on both sides of the patient's torso, the elongated horizontal arm 606 could be supported at both of its ends, rather than cantilevered.)
A mechanism 608 for imparting motion to a plunger 610 (compare 38, discussed above) is disposed at a distal end of the support arm 606. A linkage 609 is shown between the mechanism 608 and the plunger 610, and may be representative of the driving wheels (86) described hereinabove. With a hydraulic mechanism 608, for example, the linkage 609 may be a piston.
The mechanism 608 may comprise an electric motor (compare 14, discussed above), hydraulic actuators, pneumatic actuators, or any comparable means of imparting force and vertical movement to the plunger 610. The plunger 610 may be operated by any suitable means, such as the driving wheels (86) described hereinabove.
In the device 600, the plunger 610 serves as a “sternum compressing element”, and the mechanism 608 serves as the “mechanism for imparting force” to the sternum compressing element.
The vertical support element 604 may be adjusted (for example, as described hereinabove with respect to elements 30 and 32) so that the plunger 610 can come into contact with the patient's chest, and exert a downward force and resulting displacement.
As discussed above, the plunger 610 may, for example, be a 10 cm in diameter circular plate made of a substantially rigid material and covered by a soft, cushioning and biocompatible material, so as minimize harming the patient during treatment.
One or more device sensors 612 may be associated with the device, as described above, to monitor the workings (operational parameters) of the device. (Compare, for example, load sensor 62, described hereinabove.)
One or more life-sign sensors 614 may be associated with the patient, as described above, to monitor vital signs of the patient. (Compare, for example, life-sign sensor/s, described hereinabove.) These sensors 614 may include, without limitation, one or more of:
An electronic controller 620 (compare 20, discussed above) may control operation of the mechanism 608, thereby controlling at least up and down (vertical) movements of the plunger 610, including force, distance and rate, as described hereinabove. A duty cycle of compressions provided by the plunger 610 can also be controlled. (“Duty Cycle” generally refers to a ratio of “on” time versus “off” time, and a duty cycle of other than 50% may be regarded as asymmetric.)
The controller 620 may adaptively control the mechanism in response to signals from the device sensors 612 and life-signs sensors 614, as described hereinabove, and as further described hereinbelow.
A communications module 616 (compare 64, discussed above) may be provided to interface the device with external devices (such as an external defibrillator), download operating instructions, communicate with remote entities (such as off-site doctors), and the like.
A display and human interface module 618 may be provided, which may include such functions as speaker 68, microphone 70, display 21, status indicator 72, discussed above. An interface for defibrillator pads (not shown, compare
In use, the plunger 610 moves (at least) up and down in the vertical direction (z-axis) to perform the external cardiac massage, as described hereinabove. And, certain operating parameters of the plunger, such as force, distance and rate may be varied during ECM, as described hereinabove.
The device 600 may also be provided with an energy-accumulating mechanism 644 (compare 44) to assist in performing ECM.
According to an embodiment of the disclosure, various other (other than force, distance and rate) operating parameters of the plunger, such as plunger angle with respect to the patient and position (x-y location) on the patient's chest may additionally or alternatively be varied during ECM.
In
The CMD shown in
In
In
The changes in the plunger angle and/or x-y location on the patient's chest may be implemented in various ways, including for example (and without limitation), on or more of:
An advantage of changing the plunger's angle and/or position during ECM may be that the ECM procedure may be more effective and/or to reduce incidental damage to surrounding tissue (such as soft tissue).
As an example, during an ECM procedure, which may last many minutes, every few strokes the angle and/or position of the plunger may be altered (changed) slightly, followed by signals from the sensors 612 and 614 being analyzed to determine if the change had beneficial effects, then repeating this procedure until what appears to be an optimal position is located. Any of a number of known algorithms for adaptive control, such as rule-based or history, can be utilized.
As an example, during an ECM procedure, the angle and/or position of the plunger may be altered in response to offline data, such as instructions received from a remote entity.
The changing of the plunger's angle and/or position during ECM may be in conjunction with, rather than in lieu of controlling the plunger's force, distance and rate.
Changes to any of the plunger's force, distance and rate, as well as angle and/or position, may be made by the caregiver (manually).
The depth of the compressions provided by the plunger 610 can also be varied, such as dynamically, by the controller 620. For example,
The speed (repetition rate) of the compressions provided by the plunger 610 can also be varied, such as dynamically, by the controller 620. For example,
The duty cycle of the compressions provided by the plunger 610 can also be varied, such as dynamically, by the controller 620. For example,
The “pressure profile” of the compressions provided by the plunger 610 can also be varied, such as dynamically, by the controller 620. For example,
The ECM devices disclosed herein are adapted to provide messages and alarms to the operator (rescuer), sample new patient data, dispense medicaments and/or other treatments, perform any measurements related to the procedure, perform defibrillation, and the like.
The electronic controllers of the devices disclosed herein are adapted to perform their functions of varying one or more operating parameters based on an adaptive learning, expert or other program which receives (and is responsive to) one or more of device operation parameters and measured patient information.
Generally, both of the ECM devices 700a and 700b may comprise:
The elements 708, 710, 712, 714, 716, 718 and 720 may have substantially the functionality as their counterparts 608-620 in the ECM device 600.
In
In
The devices 700a and 700b may also be provided with an energy-accumulating mechanism 744a and 744b, respectively, (compare 44) to assist in performing ECM. The energy-accumulating mechanisms discussed herein may also be referred to as “force boosters”.
A mechanism (shown schematically as 743L and 743R) may be included in either or both of the straps 742 L and 742R to independently shorten the respective strap, thereby imparting tension, either evenly or unevenly (at an angle), on the patient's chest, under control of the controller.
Generally, both of the ECM devices 800a and 800b may comprise:
The elements 812, 814, 816, 818 and 820 may have substantially the functionality as their counterparts 712-720 in the ECM devices 700a and 700b.
In
In
The devices 800a and 800b may also be provided with an energy-accumulating mechanism 844a and 844b, respectively, (compare 44) to assist in performing ECM. The energy-accumulating mechanisms discussed herein may also be referred to as “force boosters”.
In both of the devices 800a and 800b, energy is transferred from a mechanism 808a or 808b into linear motion that ultimately change the length of martial\band\strap\cuff in contact with the patient's thorax. The reduction of amount of material in contact results in pressure applied on the thorax's circumferences and thus for the cardiac massage.
In order to achieve this, the driver 808a or 808b can be rotary motor, linear motor, solenoid, pneumatic piston or alike. Any of these means transfers energy via with a spool (in the case of a belt) or a gear to the circumference changing element (belt, cuff). These type of force transfer are inefficient by nature as the force if not transfer to the thorax directly, but rather goes via intermediate mediums\hardware parts (like the spool) that may add friction and residual forces.
Additional Features
In addition to, or alternative to any of the techniques for controlling the operation of an ECM device described herein, a variable-stroke automatic CPR device/system may be implemented that dynamically and intermittently may changes one or more of plunger depth, force applied, stroke repetition (speed), plunger angle, plunger position, temperature or the like based on measured patient information. Such a system may have advantages including (but not limited to):
Regarding temperature, the pumping action of the ECM device may elevate blood temperature. A certain amount of blood heating may be acceptable, but it may be desired to limit the rise in temperature so that (for example) the patient's brain will not be damaged. Thus, one of the life sign monitors can monitor blood temperature (either directly or indirectly), and the operation of the plunger can be adapted (such as slowed down) so as to maintain blood temperature within a certain limit.
In general, the operation of the sternum compressing element can be controlled in various ways to optimize the ECM and/or to minimize injury to the patient. For example, the repeated pressure of performing ECM at a given location on the patient's chest may cause injury. To minimize such repetitive force injuries, the position of the plunger can be moved around, possibly causing several smaller injuries rather than one major injury.
Other than limiting rise in blood temperature, for example, the x-y position of the plunger can be moved around (as described above) according to a pre-stored pattern so as to make the massage more effective or to reduce incidental injuries to the patient.
Memory
Various CPR devices have been disclosed with associated memory, such as to maintain operating programs, record device operation or measured patient information. However, there appears to be no recognition that device and/or patient information gathered during operation of the device may be useful for later review by health care professionals and/or equipment developers/maintainers on a patient basis, group basis, statistical grouping or other basis.
According to a feature of the disclosure, an ECM device (such as any of the devices described hereinabove) has memory 90 (
Alternatively, the device and patient data may be transmitted to another device such as by wire, wireless, or the like. The other device may comprise an external memory or processor such as a PC (personal computer) or PACS (picture archiving and communication system).
Optionally, a write-once memory device such as one-time-programmable semiconductor memory, may be used to maintain a tamper-proof record of device operation and/or measured patient information which may be useful in malpractice, wrongful death or other forensic matters.
Augmenting Force-Delivery in Belt-Type ECM Devices
As discussed above, various mechanical devices have been proposed for performing ECM. These generally include plunger (or piston type) devices, and belt-type devices.
An embodiment of a plunger-type device, having a mechanism, referred to as “energy-accumulating mechanism” (44) for augmenting force-delivery has been shown and described with respect to
The applicability of energy-accumulating mechanisms 744a, 744b, 844a, 844b to belt-type devices 700a, 700b, 800a, and 800b has also been disclosed, generally (
Belt-type devices typically transfer energy from the mechanism for imparting force (such as rotary motor, linear motor, solenoid, pneumatic piston or the like) to the sternum compressing element (such as belt or cuff) The reduction of amount of material in contact results in pressure applied on the thorax's circumferences, and thus for the cardiac massage. Any of these means transfers energy via with a spool (in the case of a belt) or a gear to the circumference changing element (belt, cuff). These type of force transfer are inefficient by nature as the force is not transferred to the thorax directly, but rather goes via intermediate mediums\hardware parts (like the spool) a that add friction and residual forces.
A compression band (belt, strap) 942 encircles the patient's torso, and has a right (as viewed) portion 942R and a left (as viewed) portion 942L. The belt 942 serves as the “sternum compressing element”. A block of material (compression pad) 944, may be located (disposed) between a portion of the compression band 942 passing over the patient's chest, and the patient's chest, substantially over the patient's heart, to direct (localize, focus) pressure at the patient's heart, when the band is cinched tight (tightened, as described below). The block 944 may be a 10 cm in diameter circular plate made of a substantially rigid material and covered by a soft, cushioning and biocompatible material, so as minimize harming the patient during treatment. The block 944 may be a compression pad filled with foam and air. The block 944 may have various degrees of resilience, and may be a bladder (of any sort) containing a viscous fluid, including a non-Newtonian fluid.
A platform (or “backboard”) 940 may be provided, for supporting the patient (in a supine position, as shown) and for enclosing (housing) the various mechanical elements and mechanisms of the device 900, as follows. The platform 940 has a central portion 940C between a left (as viewed) portion 940L and a right (as viewed) portion 940R. The platform 940 is wide enough (in the x-axis) to support a patient, and extend beyond such as for grasping the platform to move the patient.
A mechanism 908 for imparting force, such as an electric motor (not shown), drives a drive spindle 909 which may be disposed in the right portion 940R of the platform 940. The spindle 909 may be rotated in a clockwise or counter-clockwise direction, as indicated by the double-headed arrow. A drive band 946, which may be integral with or separate from the compression band 942 is wrapped around and acted upon by the drive spindle 909, and may have a free end. (If “integral”, this implies that the two ends of the compression band 942 engage the drive spindle 909.)
Any number of electronic components, including batteries, electronic controller, communications modules and the like (generally as may have been described hereinabove) may be disposed in the left portion 940L of the platform 940. These components are generally designated 911.
An end portion of the right portion 942R of the compression belt 942 passes around a spindle (or pulley) 943R, and is directed towards the spindle 909. An end portion of the left portion 942L of the compression belt 942 passes around a spindle (or pulley) 943L, and is directed towards the spindle 909. The end portions of the band 942 merge, and may be joined together, to the right of the spindle 943R.
The ends of the left and right portions 942L and 942R of the compression belt 942 may be joined directly to the free end of the drive band 946. In which case, the device 900 can be operated substantially in the manner of existing devices.
Alternatively, as illustrated, an energy-accumulation mechanism (or “force booster”, or “force-modifying” element) 950 may be disposed between the joined together end portions of the left and right portions 942L and 942R of the compression belt 942 and the free end of the drive band 946. In principle, the “force booster” is operatively disposed between the “mechanism for imparting force” and the “sternum compressing element”. Other types of “force modifying” elements are disclosed herein which may be disposed at various locations in the “drive train” from the “mechanism for imparting force” to the “sternum compressing element”.
As illustrated in
Here it can be seen that the ends of the left and right portions 942L and 942R of the compression belt 942 are affixed to the left (as viewed) end of a threaded rod 952. An end plate 953 may be disposed at the left end (as viewed) of the threaded rod 952. The free end of the drive band 946 may be joined to the right (as viewed) end of the threaded rod 952.
The spring 954 may be disposed about the rod 952, which extends through an inner circumference of the spring 954, beyond the right (as viewed) end of the spring 954. A threaded end plate 955 may be disposed on the threaded rod 952. The threaded end plate 955 may be turned so as to pre-compress the spring 954, as indicated by the two arrows facing each other. In this manner, force applied by the drive spindle 909 may be modified, consequently modifying (such as boosting) the compressions on the patient's chest.
Another force-modifying arrangement (including a force-modifying element) is illustrated in
A fixed anchor point 961 is provided within the backboard (housing) 940. The spindle 943R is mounted so as to be movable (for example, it may be on an axle disposed between two grooves, not shown). When the compression belt 942 is tensioned (such as in response to counter-clockwise rotation of the drive spindle 909), the right portion 942R of the compression belt 942 tends to pull the spindle 943R upwards and to the right. A spring, or dashpot, or other suitable force-modifying element 964 may be disposed between the fixed anchor point 961 and the spindle 943R and, as indicated by the double-headed arrow, the element 964 may boost force in either desired direction. For example, the element 964 may comprise a tension spring which, in the absence of driving (belt-shortening) force, maintains the belt 942 in a pre-compressed state.
A torsion spring (not shown) may, for example, be disposed on the drive spindle 909 which biases the drive spindle in one direction or the other (clockwise or counter-clockwise), as well as in both directions.
As indicated by the above, a spring element, a dashpot, a shock absorber or virtually any other force-altering element(s), may be added almost anywhere in the “drive train”. Assuming the torso to be an elastic medium which is being acted upon, the compressions (and rebounds) can be made asymmetrical by the addition of force-altering elements to optimize the efficacy of the massage, or to offset undesired asymmetries in the elasticity of the torso. For example, a spring may be loaded so that when the crank (for example) pushes the plunger downwards, the spring applies force in the same direction.
Whereas the force-altering elements described above may be passive devices, it is within the scope of the disclosure that an active device such as an entire “plunger package” such as described with respect to
Some (or all) of the force-modifying concepts disclosed above (belt-shortening) may be applied to a cuff-tightening ECM device, operated by pneumatic pressure (rather than an electric motor) as a mechanism for imparting force.
A compression band (including a pneumatic tube portion) 1042 encircles the patient's torso, and may have a top (as viewed) pneumatic portion 1042t and a bottom (as viewed) non-pneumatic portion 1042b. Alternatively, the entire compression band 1042 may be a pneumatic tube. The compression band 1042 serves as the “sternum compressing element”.
A block of material (compression pad) 1044 (compare 944), may be located (disposed) between the portion 1042t of the band 1042 passing over the patient's chest, and the patient's chest, substantially over the patient's heart, to direct (localize, focus) pressure at the patient's heart, when the band is cinched tight (tightened, as described below). The block 1044 may be a 10 cm in diameter circular plate made of a substantially rigid material and covered by a soft, cushioning and biocompatible material, so as minimize harming the patient during treatment. The block 1044 may be a compression pad filled with foam and air. The block 1044 may have various degrees of resilience, and may contain a viscous fluid, including a non-Newtonian fluid.
A platform (or “backboard”) 1040 may be provided, for supporting the patient (in a supine position, as shown) and for enclosing (housing) the various mechanical elements and mechanisms of the device 1000, as follows. The platform 1040 has a central portion 1040C between a left (as viewed) portion 1040L and a right (as viewed) portion 1040R. The platform 1940 is wide enough (in the x-axis) to support a patient, and extend beyond such as for grasping the platform to move the patient.
A mechanism 1008 for imparting force, such as a pneumatic pump (not shown), provides pressurized air or fluid into the pneumatic portion 1042t of the belt 1042.
Various valves, petcocks, dampers and the like, generally designated 1009 may be provided in fluid communication between the pump and the pneumatic portion of the belt, for controlling (modifying, altering, enhancing) the flow of air or fluid into the pneumatic (inflatable) belt portion 1042t. these elements 1009 may also permit venting pressure from the pump 1008 and/or pneumatic belt portion 1042t. These elements 1009 may act as an energy-accumulation mechanism (or “force booster”, or “force-modifying” element).
Any number of electronic components, including batteries, electronic controller, communications modules and the like (generally as may have been described hereinabove) may be disposed in the left portion 1040L of the platform 1040. These components are generally designated 1011.
The non-pneumatic bottom portion 1042b of the band 1042 may simply be attached to the left portion 1042L of the platform 1040. Alternatively, the non-pneumatic bottom portion 1042b of the band 1042 may enter the platform (housing) 1040, may pass around a spindle 1043L (compare 943L) and be connected via an energy-accumulation mechanism (or “force booster”, or “force-modifying” element) 1050 (compare 950) to a fixed point 1051 within the platform housing 1040. And, the spindle 1043L may be connected via a spring, or dashpot, or other suitable force-modifying element 1064 (compare 964) to a fixed anchor point (1061) compare 961) within the platform housing 1040.
A “hybrid” device, using belt-shortening and cuff-tightening could be formed, for example, by substituting a motor drive mechanism (comparable to 908, 909L;
Alternatively, a substantially entire belt-shortening mechanism (including belt), as shown in
A compression band (belt, strap) 1142 (compare 942) encircles the patient's torso, and has a right (as viewed) portion 1142R and a left (as viewed) portion 1142L. The belt 1142 serves as the “sternum compressing element”. The band 1142 may be intermittently tightened (and loosened) by an electric motor and associated elements (not shown, see motor 908 and spindle 909, for example, in
An inflatable pneumatic bladder 1144 (compare compression pad 944) may be located (disposed) between a portion of the band 1142 passing over the patient's chest, and the patient's chest, substantially over the patient's heart. The bladder may be (for example) approximately 10 cm in diameter.
A pneumatic tube 1042n, which need not serve any structural (mechanical) function, communicated fluid (including air) pressure from a pneumatic source (not shown) which may be disposed within the platform (housing) 1149 (compare 1008 disposed in 1040;
The bladder 1044 may be intermittently inflated (and deflated), for performing cardiac massage.
Generally, the bladder 1044 may be operated independently of the belt 1142, in various ways:
In the description and claims of the application, each of the words “comprise” “include” and “have”, and forms thereof, are not necessarily limited to members in a list with which the words may be associated.
The disclosure has been described using various detailed descriptions of embodiments thereof that are provided by way of example and are not intended to limit the scope of the disclosure. The described embodiments may comprise different features, not all of which are required in all embodiments of the disclosure. Some embodiments of the disclosure utilize only some of the features or possible combinations of the features. Variations of embodiments of the disclosure that are described and embodiments of the disclosure comprising different combinations of features noted in the described embodiments will occur to persons with skill in the art. It is intended that the scope of the disclosure be limited only by the claims and that the claims be interpreted to include all such variations and combinations.
