IT202100000356A1 - A DEVICE FOR MEASURING PAIN - Google Patents

Description

Description accompanying the patent application for

industrial invention entitled:

TITLE

A DEVICE FOR MEASURING PAIN

Scope of the invention

The present invention refers to the technical sector of devices for medical use.

In particular, the invention refers to an innovative device capable both of quantifying the pain of a patient in a precise and objective way and of allowing for more pain relief. objective evaluation of therapeutic efficacy.

Brief outline of the prior art

The necessity? to measure or otherwise classify the level of individual pain in a more? objective ? a necessity? of significant importance not only for pain therapists but also for all clinicians who have to control pain, as for example in all surgical disciplines for postoperative pain.

The availability of logical levels to determine with greater objectivity? pain becomes important for setting up adequate therapies and evaluating the results.

The most popular method today? the use of a pain scale proposed in numerous graphic versions. However, despite efforts to make it sensitive and specific, as well as objective, it remains an intrinsically subjective method, limited by the lack of repetitiveness, also because clearly subject to variations in the patient's mood and moreover also influenced by the healthcare professional who administers it.

An example of a pain scale? the one shown in figure 1 of prior art. It shows colors and images of ?emoticon? which psychologically influence the examinee, thus losing the necessary objectivity.

Another example with better yield? a non-graduated scale (Fig. 2) of known length (for example 10 cm.) which is digitized by the operator in the second instance by measuring in millimeters the level at which the sign of pain is marked by the patient. This allows you to avoid influencing the judgment with misleading images and symbols but still remains a subjective test. Such a pain scale structure ? less immediate for many patients, also more? difficult to administer to elderly patients and still in patients in the post-operative period.

To overcome these limitations, skin rubbing systems with flexible filaments of variable sections are also known and used to evaluate the sensitivity thresholds of the skin. and hyper-algic.

These flexible filaments, known as ?Von Freye filaments?, are based, as a mechanism of action, on the superficial mechanical stimulations of the Pacinian corpuscles. Isn't this method? For? precise as the skin of each individual has its own sensitivity? highly variable and independent of the intrinsic thresholds of the corpuscles and the method ? operator-employee. Furthermore, this method little used in the hospital setting, if you want to evaluate more? times in the same day the level of pain; and still the same method not ? suitable for evaluating the level of pain if it occurs in deep areas of the human body and in the joints.

Summary of the invention

AND? therefore felt the need for an assembly that allows an assessment of the pain threshold that is precise and objective and that allows objective monitoring of pain over time.

In particular, ? having felt the need for an assembly that allows an assessment of the pain threshold that is precise and objective, with digital feedback systems to objectify the thresholds of stimulations of different nature applied and from which to derive the individual thresholds of perception of the stimulus.

AND? therefore, it is an object of the present invention to provide a pain measurement assembly which overcomes the aforementioned technical drawbacks.

In particular ? The object of the present invention is to provide a pain measurement assembly which is not only objective but also repeatable with precision and simplicity. in?use, reducing the limitation due to?experience and manuality? of the operator who carries out the analysis.

These and other objects are achieved with the present pain measurement assembly according to claim 1.

Such a measurement assembly for measuring a pain threshold in a subject comprises:

- A pulse generator for electrostimulation;

- A device for generating a vibration;

- A device for generating a jet of a

gas flow.

In this way all the aforesaid technical drawbacks are solved.

In particular, ? now it is possible to generate (preferably in succession) thanks to the aforementioned assembly, an electrical stimulation, a mechanical one (through a vibrating device) and a stimulation by sending a flow of gas, generally air, at a certain pressure and/or temperature impacting a point on the subject's body.

The perception of these stimuli allows you to determine a pain threshold for each patient and allows you to evaluate its modification over time in relation to any therapy applied.

The execution order can? be any, for example the electrical stimulation first, followed by the mechanical vibrating one and then, lastly, the one through the jet of air.

Thanks to these stimulations you can? create a scale of perception of the pain threshold that is objective and therefore that solves all the technical problems associated with current solutions.

Preferably, advantageously, the jet of air can be at variable temperature in order to better stimulate perception for the patient.

Preferably, advantageously and in combination with the above or independently of the above, the mechanical vibration can be at intensity? and/or variable frequency.

Eventually the vibrating body pu? moreover, it must be regulated at a predetermined temperature.

Advantageously, the pulse generator can? for example, be programmed to generate one or more? pulse trains.

Advantageously each train pu? be formed by at least two pulses, preferably four.

Advantageously, each impulse can? be in the form of a? square wave, or triangular or sinusoidal without excluding, therefore, the possibility? that each train is composed of a succession of impulses of different shapes or all of the same shape.

Advantageously, the amplitude of each impulse can? for example, be included in a range between 0V and 70V and even more? preferably between 0V and 50V ( V = Volt).

Advantageously each impulse can? have an adjustable duration.

For example, advantageously, the duration of each impulse can? be in the range of 50 microseconds to 1 millisecond.

Advantageously, the time interval between one pulse and the next in a train of pulses can? be adjustable and/or advantageously the time interval between a train and the next can? be adjustable.

Advantageously, the device for generating the vibrations includes a? vibrating device to which a vibration is transmitted by means of a vibrating mass operable in such a way as to generate a vibration at a predetermined frequency.

Advantageously the? intensity? and/or frequency of the vibration can be adjustable.

Advantageously, for how already? anticipated above, the device to generate the vibrations pu? also include first means of temperature control programmed to bring the? extremity? vibrating at a predetermined desired temperature.

Advantageously, said device for generating a flow of gas can? be programmed to generate gas flow pulses, for example air, adjustable according to a duration of each pulse included in a range between 0.5sec and 2 sec.

Advantageously, as anticipated above, second temperature control means can also be included, preferably in the form of a Peltier effect thermocouple 43, the function of which is that of allowing regulation of the temperature of the gas jet, for example air as mentioned, at a predetermined desired temperature.

Advantageously, the pressure can? be adjustable in a range between 2 and 4 atmospheres.

AND? Also described here is a method for determining the pain threshold in a subject and comprising the following steps which can be performed in any sequential order:

- The stimulation of the subject through the administration of one or more? trains of electrical impulses to generate electrostimulation;

- The stimulation of the subject through a vibration generated with a vibrating device;

- The stimulation of the subject through jets of a gaseous flow, for example jets of air, at a predetermined pressure and/or temperature.

AND? Also described here is the combined use of an electric pulse generator for electrostimulation, a device for generating a vibration and a device for generating a jet of a gaseous flow to generate in sequence, according to any order, a or more trains of electrical impulses, a mechanical vibration and a flow of gas at a predetermined pressure to measure a pain threshold in a subject.

As mentioned, the order of execution pu? be any, for example first vibration then gaseous flow and only last electrical impulses.

Brief description of the drawings

Further characteristics and the advantages of the present device, according to the invention, will be more clearly with the following description of some of its embodiments, given by way of non-limiting example, with reference to the attached drawings, in which:

- Figure 1 and figure 2 both show two examples of solution according to the prior art;

- Figure 3 ? a schematization of a part of the assembly object of the invention and in particular of the central control console to which the electrodes for electrical stimulation and the handpieces for the jet of air and the generation of vibrations are connected;

- Figure 4 ? a graph relating to a generation of pulse trains while figure 4A shows some examples of pulse trains;

- Figure 5 schematises the device which generates the vibration;

- Figure 6 schematises the device which determines the jet of flow of gaseous, for example air, under pressure.

Description of some preferred embodiments

The invention mainly consists in the combination of three components which together generate the assembly to determine a pain threshold measurement.

These three components will be described in detail immediately below and include:

- A pulse generator for electrostimulation;

- A device (for example a handpiece) for the generation of mechanical stresses, preferably vibrations at a certain frequency;

- A device (for example a handpiece) for generating a flow of gas (for example jets of air) at a certain pressure, preferably at adjustable pressure values;

- AND? it is then possible to provide a possible system for regulating the temperature of the gaseous flow (for example air) and/or of the vibrating part of the device for generating the vibrations.

The whole thing can be integrated into a single object integrating these components and each one used for its specific function.

Alternatively, these aforementioned components could be separate parts and therefore define separate devices which for? they work and are controlled together in synergy.

The components introduced above are therefore described in both structural and functional detail below.

The preferred configuration provides for a single controller 1 (or control device 1, if you prefer) to which the three components introduced above are connected and with the controller used to control their functionality.

Preferably, therefore, the? assembly ? therefore controlled by said main controller, schematically shown in Figure 3, to which the various parts described in detail below are connected.

THE CENTRAL CONTROLLER:

Figure 3 shows the controller 1 to which the components forming the pulse generator, the vibration generator and the one for generating the air jet are connected in a removable manner.

Said controller 1 therefore has internal control electronics (for example one or more specially programmed processors) to control the operation of the various components which can be connected to it.

It ? formed by a frame in the form of a box 2 which contains the electronics for operation inside.

As shown in figure 3, the box 2 comprises a front face 3 provided with a control panel 4 through which to control the operation and/or through which to read the data.

The control panel can have ?layout? different and therefore what is represented in figure 3 is not ? to be considered limited.

Obviously can? be adopted digital screen technology, possibly of the ?touch screen? type.

In particular you can foresee a ?touch-screen? from 5? for setting the device operating parameters.

The box 2 contains the electronics suitable for being able to generate the trains of synthesized electric impulses, controlled by a microprocessor, which are therefore sent through a cable 5.

The same goes for the generation of vibrations and jets of air as, through it,? It is possible to operate the vibrations and air jets at the desired values.

Figure 3 in fact shows the attachments (in particular three attachments 50, 51, 52) to which it is possible to connect to each one, preferably in a removable way, the cable 5 for the electrodes (6a, 6b), the cable which goes to the vibration generator and the cable for the device that generates the pressurized air jet.

Each cable can therefore end with a ?Jack Connector? fit to fit into the appropriate attachment (50, 51, 52).

The control panel therefore allows you to adjust the desired values for the generation of electrical stimulation impulses, vibrations and air jets.

THE PULSE GENERATOR DEVICE:

Again with reference to figure 3, the cable 5, therefore, connects on one side with the box 2, in particular with the connection 50, while, on the opposite side, it ends with at least one pair of electrodes (6a, 6b ).

In this way ? It is possible to generate a potential difference between the electrodes (stimulating) which translates into a passage of current in the body which moves along the segment between one electrode and the other.

In essence, therefore, a digitally controlled electric pulse generator is created to govern all the intensity parameters? (duration and amplitude) and their delivery frequencies.

The potential difference introduced ? in the form of a pulse train each pulse consisting of a potential difference.

This current will result? therefore adjustable and modulable being adjustable and modulable as amplitude, duration, frequency and repetitiveness? of emission, both the single pulse and the entire train of pulses.

In particular, sequences of pulse trains are administered with stimulating electrical charges varying in the parameters of amplitude, duration and frequency which translate into trains of currents of stimulation of the various nerve fibers and corpuscles used for the transmission of pain in the body.

The current passes through the body in the form of single pulses or trains of pulses which penetrate transcutaneously stimulating the nerves with the well-known TENS technique (transcuateneous electrical nerve stimulation)

According to the invention, therefore, the pulse generator for electrostimulation 1, object of the invention, must be programmed in such a way as to be able to generate:

- Waveform: A specific programmable waveform in shape and intensity? to compose a single pulse or a train of programmable pulses. The wave can therefore be for example square and/or triangular and/or sinusoidal.

AND? for example, is it possible to deliver four pulses spaced out by a second TOF (train of four) and which ? a method well known by anesthesiologists.

Preferably also the time, both between pulses that make up the train and that of delivery between the various trains, can? be programmable.

Figure 4 therefore shows an example in which two square wave trains (train 1, train 2) are sent according to a time interval T between one train and the next which preferably must be greater than or equal to 500ms (milliseconds). Every train? preferably formed by a block of at least two or more? pulses, typically four.

- Pulse amplitude: This amplitude must be adjustable between 0V and 70V, even more? preferably between 0V and 50V. This breadth can preferably be adjusted using a multiple potentiometer equipped with a knob with a precision graduated scale or via an encoder equipped with a knob with a precision graduated scale.

Figure 4 shows an example of two trains at a value below 25V but above 0V.

- Time duration of each impulse: Each impulse can? have adjustable duration between 50 microseconds and 1 millisecond.

there ? also a possibility? to generate continuous stimulation at 50Hz.

The operating values indicated above are considered optimal for the operation and purposes of the invention and therefore to stimulate the user in such a way as to be able to measure the sensation of pain, obviously without ever causing physical damage of any kind.

Figure 4A shows, by way of example, some trains of triangular or square wave pulses.

HANDPIECE FOR THE GENERATION OF MECHANICAL STRESSES:

Figure 5 describes the device for generating mechanical stresses which, by means of a cable, is always connected to the box of figure 3 (for example through the connector 51 or 52) and which ? therefore controllable through this box, in particular through the control screen 4.

The device of figure 5 (also called handpiece) ? preferably a vibration generator.

It ? preferably equipped with an eccentric motor (e.g. a micromotor). The rotation of the eccentric ? such as to generate the desired vibration, at a predetermined frequency.

In particular, figure 5 shows the vibrating mass with the number 30.

An electric motor, for example a stepper motor, for example drives in rotation an eccentric which forms the vibrating mass as a whole.

The rotation of the eccentric determines the vibration.

It can preferably be made in 3D printing with a handleable shape and conical tip for the transmission of vibrations to the skin.

Again as shown in figure 5, the device ? equipped with a stimulating tip 31 which vibrates following activation of the motor, thanks to the eccentric which is set in rotation.

Tip 31 can? have various shapes and stiffness.

Again, the frequency and intensity? of vibration ? controlled by the control panel through the microprocessor which controls the speed? of rotation of the electric stepper motor.

The microprocessor? obviously installed in the box 2 which conforms to the central controller introduced above.

The frequency of the vibration and the intensity? more appropriate for the purposes may vary and in any case may be modulated and therefore better defined on the basis of experimental data based on specific needs.

AND? is it possible a solution with more? of a motor with different eccentric masses and also placed in the same handpiece and selectable.

The handpiece can possibly be equipped with first means of temperature control, for example a thermocouple, which can? heating and/or cooling the vibrating tip to a predetermined temperature.

Different temperature thresholds could be set.

Preferably, the delta of temperature that can be reached, with respect to the ambient temperature in which one operates, is about 20? C more? or less than ambient temperature.

Preferably you can? use the PELTIER effect to reach this temperature difference.

Therefore, if one operates in an environment at a temperature of about 24?C, temperatures can be generated up to a maximum of about 44?C or a minimum of about 0?C.

In this way it will be It is possible to feel a vibration through a cold or hot tip.

HANDPIECE FOR THE GENERATION OF CONSTANT PRESSURE AIR JETS:

Figure 6 shows the device (also called handpiece) for generating gas jets (generally air) at adjustable pressure.

The pressure, once adjusted, remains constant at the adjusted value.

As indicated in figure 6, ? including an air compressor 40 which generates the necessary delivery pressure.

In this way the air contained in special tanks can be sent to a nozzle 45, at said operating pressure.

Two tanks are therefore foreseen, one of which (41) for hot air and one (42) for cold air.

Second temperature control means are also included, preferably in the form of a Peltier effect thermocouple 43, the function of which means is that of heating the gas contained in a tank to a certain temperature and cooling the gas in the other container with a difference in temperature between them, for example 20 degrees centigrade.

In this way a tank will contain? one hot gas (for example hot air) and the other a cold gas (for example cold air).

AND? then a solenoid valve 44 is provided for each tank for generating the trains of air jets.

The solenoid valve is controlled by the micro-processor, always integrated in the box of figure 3, in opening/closing thus determining the passage of hot or cold compressed air or a mix of the same through the nozzle 45.

The nozzle can for example containing within it an electromechanical actuator, which controls a pin shutter movable between an open position and a closed position.

The microcontroller therefore commands the opening of the solenoid valves (one of them or both) and commands the activation of the electro-mechanical actuator which can? open the obturator for the outlet of the gaseous flow under pressure, generally air as mentioned.

Also in this case the handpiece can? be made in 3D printing with a handleable shape and conical tip for the emission of air jets at a fixed distance from the skin.

The shape of the handpiece 45 can be similar to that of mechanical stimulation with the various nozzles of various sections, for example from 0.5 to 2 mm in diameter and also of the interchangeable type.

The compressed air that will come? emitted at adjustable pressure (governed by the pressure regulator) will be able? be drawn from two distinct compressed air tanks with different temperatures (hot/cold) governed by Peltier effect thermocouples placed between them.

The whole ? can be powered by an external rechargeable battery with a special battery charger.

Preferably, but not necessarily, you can have pulses of air lasting every one that can? go from a minimum of 0.5 sec to 2 sec with an adjustable pressure value between 2 and 4 atmospheres with manual trains (which are activated manually) or automatically preset.

The values indicated above are considered preferred for the purposes but do not exclude other possible values which could be useful from experiments.

USE OF THE ASSEMBLY:

The operator (doctor or algologist) decides the sequence of use of the various stimuli.

For example, starting from air stimulation of intensity? progressive and variable temperatures up to establish the sensitivity thresholds? equivalent to VonFrey filaments with jets of hot air, cold air or at room temperature.

Later you can? proceed to mechanical vibratory stimulation always with the same purpose, so by varying the mechanical vibratory stimulations at intensity? growing.

Finally, we continue with the electrical stimulations that will be combined in trains of impulses of various shapes, intensities and intensity. and frequency increased in intensity? until the nociceptive threshold is reached with a digital system of objectification of the signal.

A processor can? acquire the thresholds of intensity? of air flows, vibratory stimulation and current that are perceived by the user to determine an objective pain threshold value according to a predetermined algorithm, evaluating any changes over time also in relation to the therapy he is taking.

Claims (10)

1. An assembly for measuring a pain threshold in a subject and comprising: - A generator of electrical impulses for electrostimulation; - A device for generating a vibration; - A device for generating a jet of gas. 2. The assembly according to claim 1, wherein the pulse generator is programmed to generate one or more? trains of impulses and in which each train ? formed by at least two pulses, preferably four. 3. The assembly, according to claim 2, in which each pulse ? a square or triangular or sine wave. 4. The assembly, according to claim 2 or 3, in which the amplitude of each pulse ? between 0V and 70V, preferably between 0V and 50V. 5. The whole, according to one or more? of the preceding claims from 2 to 4, wherein each pulse has an adjustable duration, preferably said duration being included in a range between 50 microseconds and 1 millisecond. 6. The whole, according to one or more? of the previous claims, in which the time interval between one pulse and the next in a train of pulses ? adjustable and in which, furthermore, also the time interval between one train and the next? adjustable. 7. The assembly according to claim 1, wherein the device for generating the vibrations includes an extremity vibrating mass (31) to which a vibration is transmitted by means of a vibrating mass (30) in such a way as to generate a vibration at a predetermined frequency, preferably at an intensity and/or adjustable frequency. 8. The assembly according to claim 1 or 7, wherein said device for generating vibrations comprises first temperature control means programmed to bring the end of the vibration to vibrating at a predetermined temperature. 9. The assembly according to claim 1 wherein said device for generating a jet of gas flow is programmed to generate gaseous flow pulses adjustable according to a duration of each pulse included in a range between 0.5sec and 2 sec at an adjustable pressure in a range between 2 and 4 atmospheres, preferably including second temperature control means to allow for regulation of the flow temperature. 10. The combined use of an electrostimulation pulse generator, a vibration generating device and a gaseous stream jet generating device in such a way as to generate a sequence, in any order sequential, of: - One or more? electrical impulse trains; - A mechanical vibration; - A gaseous flow at a predetermined pressure; - In such a way as to be able to measure a pain threshold in a subject.