WO2023007368A1

WO2023007368A1 - Monitoring device of an oxygen concentrator

Info

Publication number: WO2023007368A1
Application number: PCT/IB2022/056883
Authority: WO
Inventors: Matteo Crescini
Original assignee: Oda Ossigeno Dall'ambiente S.R.L.
Priority date: 2021-07-29
Filing date: 2022-07-26
Publication date: 2023-02-02
Also published as: EP4377966A1

Abstract

A device (100) for monitoring the oxygen inhaled by a user and produced by an oxygen concentrator is described, said device comprising: - means (SF) for detecting the oxygen flow, - means (SP) for detecting the purity of the oxygen, - means (ST) for detecting the oxygen temperature, - means (SH) adapted to detect the humidity of the environment in which the concentrator is arranged, - means (QA) adapted to detect the air quality of the environment in which the concentrator is arranged, - means (ST) adapted to detect the temperature of the environment in which the concentrator is arranged, a control unit (1 ) provided with a microprocessor and with a memory and adapted to receive the signals coming from the totality of said means; said control unit (1 ) is adapted to determine the real purity oxygen volume (RPOV) in response to the signal coming from said means for detecting the oxygen flow and as a function of the other signals coming from the other means and received during the period of time (t ₁ - t ₀) in which the oxygen flow remains other than zero.

Description

MONITORING DEVICE OF AN OXYGEN CONCENTRATOR

The present invention concerns a monitoring device of an oxygen concentrator, in particular for a stationary oxygen concentrator used at home by a user.

It is known in the state of the art that patients with chronic or acute respiratory and lung pathologies may benefit from oxygen therapy, i.e. , the "supply of supplementary oxygen to a patient for medical treatments". In the past, patients undergoing oxygen therapy had to use oxygen cylinders, i.e. cylinders filled with a certain volume of oxygen, which had to be filled or replaced once oxygen was depleted. Today, patients can also use oxygen concentrators, which continuously filter nitrogen from the air in the environment to provide the user with a flow of oxygen-rich gas. Oxygen concentrators are considered a safer, more convenient and cheaper alternative to oxygen tanks or to pressurised cylinders and are used both in hospitals and in patients’ homes. The oxygen concentrators used at home are of two types: portable (which can also be used outside the home) or stationary (which can be used only at home).

The published guidelines for long-term oxygen therapy do not recommend the use of the concentrator in the case of flows > 5 LPM. If flows > 4 L/min are required, the use of the concentrator should be assessed based on the clinical characteristics of the patient. In the event that the treatment is intended for a patient who is not very reliable in complying with the instructions for the safe use of liquid oxygen, it is considered appropriate to prescribe the concentrator.

The existing oxygen concentrators are provided with devices adapted to determine the oxygen taken by the patient by controlling the oxygen flow towards the patient.

In view of the state of the art, the object of the present invention is to provide a monitoring device of an oxygen concentrator that is different from those known.

In accordance with the present invention, said object is achieved by means of a device for monitoring the oxygen inhaled by a user and produced by an oxygen concentrator, said device comprising:

- means for detecting the oxygen flow,

- means for detecting the purity of the oxygen,

- means for detecting the oxygen temperature,

- means adapted to detect the humidity of the environment in which the concentrator is arranged, - means adapted to detect the air quality of the environment in which the concentrator is arranged,

- means adapted to detect the temperature of the environment in which the concentrator is arranged,

- a control unit provided with a microprocessor and with a memory and adapted to receive the signals coming from the totality of said means, characterized in that said control unit is adapted to determine the real purity oxygen volume in response to the signal coming from said means to detect the oxygen flow and as a function of the other signals coming from the other means and received during the period of time in which the oxygen flow remains other than zero.

In particular, the device allows to optimize the intake of the Purity Oxygen Volume, that is the Purity Oxygen Volume (POV) of the patient with chronic respiratory pathology and connected to a stationary oxygen concentrator at his home, dynamically comparing the so-called RPOV, that is, the real Purity Oxygen Volume taken by the patient and the OPOV one, that is, the optimal Purity Oxygen Volume so that a caregiver can intervene on the patient to modify the parameters of the oxygen concentrator so that the intake of the patient's purity oxygen volume is always the optimal one. The apparatus also contributes to achieving the non-secondary objective of optimizing the so-called "long term therapeutic compliance performance index" (LTCI) of the patient.

Preferably, when the device is first switched on, it connects to a dedicated WEB Server and downloads the data relative to the therapy that were uploaded therein and this happens by following a continuous process of acquisition of the inputs and of processing the outputs: in the connection, each device feeds an existing database with the value updated to the last detection of each parameter that defines the individual rules, consequently updated continuously and over time, for each apparatus connected to the network. The apparatus allows to reach the Optimal POV for the specific patient who uses a specific concentrator and closes its iterative process when LTCI is equal to one, that is, it reaches the value 100% and/or it resumes it automatically when it deviates for a settable period of time. And this for each period of the oxygen therapy set by the specialist who prescribed the home treatment with the oxygen concentrator.

The therapeutic compliance of the patient is improved with the device of the present invention. The therapeutic compliance includes not only the compliance by the patient with specialist's prescribed treatment, such as the oxygen, but also with the diet, the physical exercise, or the lifestyle changes. If the patients do not follow or adhere faithfully to the treatment plan prescribed by the specialist, the expected beneficial effects of even the most accurate and scientifically based treatment plan will not be achieved.

The volume of oxygen taken by the patient, not the flow, is used as a benchmark for the optimal taking charge of the patient with chronic pathology. The use of the absorbed oxygen flow as a parameter for setting the oxygen therapy does not consider the dynamics of the treatment; setting the therapy on the volume of oxygen [i.e. on the (oxygen flow) x (unit of time)] absorbed allows to introduce the dynamic factor in the management of the therapy: remotely, the specialist can intervene on this dynamics by following the course of the system variables over time, also through a non-synchronous access to a dedicated WEB Server.

For the patients enrolled in an OTLT (Long-Term Oxygen Therapy) project, in most cases the flow rate of oxygen (O2) is not optimal and this causes them (additional) respiratory stress, especially because they encounter difficulties in adjusting the oxygen supply, that is, the amount of oxygen intake over time (the so-called Ό2 Volume”).

In particular, on the one hand, the adherence of the patient under OTLT to O2 therapy (and this does not include only the adherence to the treatment plan prescribed by the specialist, but also observing the diet, the physical exercise, the positive lifestyle changes, etc.) is low and the adjustments of the oxygen (O2) dosage must be obtained manually, not always adapting to the patient's oxygen needs in a timely manner. On the other hand, if the patients do not follow or adhere faithfully to the treatment plan prescribed by the specialist, the beneficial effects expected even from the most accurate and scientifically based treatment plan cannot be achieved.

A new relationship between patient and specialist for chronic diseases is thus wished, characterized by "informed" and "active" patients, to which the device can respond, which allows to set up a monitoring system, designed with the patient in the middle and able to offer a personalized oxygen delivery (O2) and allowing the optimization of the total oxygen supply (O2) and therefore of the Total Volume of oxygen (O2) supplied to the patient.

The key element (and the innovation element of the invention) is therefore the involvement of the patient in the treatment path by leveraging the variable "time" (the time of use of the device by the patient) and considering the variable "flow" as fixed (and whose definition is the sole responsibility of the specialist).

In this, the invention differs from any other, because it adopts an approach:

-whose benchmark for the optimal taking charge of the patient with chronic pathology is the "volume of oxygen taken in by the patient", that is, the "oxygen supply", indicating the "time" to the patient, whereas with regard to the specialist it starts from the setting of the "flow" (as an exogenous system variable);

- that "empowers the patient", placing him at the centre of the home care programme, having him committed to the treatment (and therefore to the optimal time of use), because (finally) he is an active part of the process and not a passive part.

- "dynamic", because it has at its centre the variable "time of use" of the device and not the static variable "flow": the specialist's decisions are based on the "dynamics" of the treatment, while he follows the course of the system variables over time.

The focus on the "dynamics" is based on the difference between "oxygen flow volume" and "oxygen flow rate": the "volume" describes the total amount of oxygen (O2) used in a given period (the so-called “oxygen supply”), whereas the "flow" refers to the instantaneous speed at which oxygen moves within the tube connected to the patient at the exit from the concentrator. At the same speed, therefore, the amount of oxygen (O2) delivered to the patient depends on the time: basing the therapeutic decision on the time and not on the flow moves the paradigm of the treatment from the specialist (who sets the flow upon discharge, that is, the "speed"), to the patient, in line with the aforementioned trends in the sector, so that the "self-management of the patient is inevitable"; working on the volume therefore allows the patient to be a co-player in his own adherence, adapting the time (and therefore the total oxygen supply) of the treatment, that is, how long being connected to the concentrator during the day, at the same flow (the determination of which is for the specialist), as a function of the outputs of the invention at the base of the medical device.

It is possible to measure the energy absorbed by the oxygen concentrator to reimburse the cost incurred by the patient and prolong the autonomy of use of the medical device. The concentrator is connected to a wall electrical outlet. The power supply could fail and the oxygen delivery could end, so an autonomy of the concentrator must be ensured in the event of a sudden termination of the main power supply. Electricity consumption is a cost that the patient incurs and that must be reimbursed by the National Health Service (NHS) to guarantee all patients equal access to the treatments regardless of their spending capacity.

The device indicates the correct purity oxygen volume that the patient must set to ensure the best therapeutic compliance, calculated starting from the flow and in the unit of time, even non-continuous. The flow regulation is manual, at the care of the patient who may make mistakes and/or set the value at a higher flow than necessary, because, given the pathology, he has a lower sensitivity to real flow of assimilated oxygen, which he tends to underestimate. It is necessary for the correct delivery of oxygen with respect to the prescription to be made clear to the patient at all times. An automatic flow regulation would be desirable, as well as feasible, as a consequence of the present invention, but this modification is preferable provided that it is always under the direct supervision of the specialist.

An effective monitoring of the therapeutic compliance is ensured between specialist visits, which can also be six months apart, to provide evidence of the progress of the disease. It is important for the patient to have evidence of the progress of his disease, through a continuous monitoring, possibly by telemedicine and accessible remotely from an operations centre; this by all authorised actors interested in the service. The use of the concentrator at flows lower than or equal to 5/6 LPM can be an alternative to the more expensive liquid oxygen cylinder (since the impairment of the patient with high-flow therapy is greater), to ensure equivalence of output (concentrator/cylinder), the assessment of therapeutic compliance is even more necessary. Therefore, a real-time monitoring of the delivery of oxygen to the patient and other boundary parameters to measure the therapeutic compliance is optimal.

The environment where the patient takes in oxygen must be purified to achieve an optimal level of filtration of the concentrator. This is especially so as not to affect the intake of oxygen from the concentrator. The place where the patient takes in the oxygen is therefore an important variable in the assessment of the therapeutic compliance.

The movements of the concentrator must be accounted for, to take into account the static nature of the oxygen intake, which determines when and where the therapy was performed. The patient undergoing oxygen therapy has a pathological impairment that makes him fragile, so the weight of the medical device is a critical element in the restriction of his movements. The course of the patient's physiological parameters is also an effective measure of the progress of the therapy. Normally, the patient autonomously uses a medical device to measure these physiological parameters and may misuse and/or miscommunicate the measurement to the specialist. A direct measurement and an automatic acquisition of these values is sought in order to avoid measurement errors. A constant measurement alert guarantees to the patient the definition of a measurement agenda that allows him/her not to forget to keep his/her health under control. The COVID emergency has shown the possible need of having to deliver oxygen to several patients at the same time (split). The delivery of oxygen from the concentrator is in most cases guaranteed for a use by one patient at a time, whereas the present apparatus allows the simultaneous use by at least two patients.

The length of the cables for the delivery of the oxygen flow to the patient can be an impediment to the optimal usability of the product. The proper housing of the apparatus at the concentrator, prevents the patient from tripping over the cables and optimises the usability thereof.

The perception of the disease and the relative psychological stigmatization also derives from the perception of the device used as a medical device. Masking the medical device in a piece of furniture contributes to a better quality of life for the patient because it improves his psychological state.

The use of a fuzzy logic improves the self-adaptive potential of the system, since all the apparatuses on the market are connected to the reference and dedicated WEB Server.

It is necessary to compare more and more the use of the concentrator as an alternative to the liquid oxygen, in order to have concrete data that allow people to choose the concentrator and thus to save money (the concentrator, for patients with 5/6 LPM therapy is more convenient, but sometimes people are sceptical about adopting the concentrator because they assume that it cannot guarantee a compliance comparable to liquid oxygen in a cylinder, which is, however, useful for patients treated up to 15 LPM).

The remote control of this apparatus allows to break down the barriers of taking charge of the chronic patient, especially in times of COVID.

The device therefore provides optimal assistance to the patients with chronic pathologies, helping them to fully grasp (and finally) their role in the self-management of the disease: as mentioned, for the self-management to be effective, it is in fact necessary to be proactive in the involvement required by the specialist. The use of an "optimal volume" approach, where the specialist sets the "flow" and the system shows the patient the "optimal time" to which to refer achieves the desired coordination between all the subjects involved, improving the assistance for the patients with chronic pathologies, who are (finally and as desired by the literature) placed in the middle of the treatment project.

The characteristics and the advantages of the present invention will become clear from the following detailed description of a possible embodiment, illustrated by way of non limiting example in the attached drawings, in which:

Figure 1 is a top view of the monitoring device for the oxygen delivered by an oxygen concentrator positioned at the concentrator in accordance with the present invention; Figure 2 is a schematic view of the device of Figure 1 connected to the rear face of the concentrator;

Figure 3 is a schematic side view of the device of Figure 1 connected to the concentrator; Figure 4 is a view of a suction cup used to connect the device of Figures 2 and 3 to the oxygen concentrator;

Figure 5 is a diagram of the device of Figure 1 Figure 6 shows the fuzzy logic of the device of Figure 1 ;

Figure 7 shows a system comprising a plurality of monitoring devices for the oxygen delivered by a respective plurality of concentrators connected to a WEB Server.

A monitoring device 100 for the oxygen delivered by an oxygen concentrator 300 in accordance with the present invention is described in Figures 1-6. The device allows the optimization of the oxygen intake from the concentrator, at home, in particular for a patient undergoing low-flow oxygen therapy at home, i.e. up to 5/6 Litres Per Minute (LPM).

The device 100, visible in Figure 1 , is connected to the oxygen concentrator used by the patient through a tube IN for the inlet of the oxygen exiting the concentrator 300 and another tube OUT for the outlet of the oxygen from the device 100; from the tube OUT the oxygen monitored by the device 100 returns to the concentrator 200 for the delivery thereof to the patient.

Preferably the device 100 is removably connected to the concentrator 300 used by the patient (Figures 2-4), preferably it is connected to the flat rear face 102 of the concentrator 300.

Preferably, the device 100 is connected to the concentrator 300 by means of suction cups 400 of the type comprising a main part 401 for fixing to a face of the concentrator, for example the rear face 102, and a tightening screw 402. The device 100 preferably comprises two suction cups 400 and is arranged so that the main parts 401 of the suction cups 400 adhere to the face 102 of the concentrator; the screws 402 for fixing the device 100 to the concentrator 300 are then tightened.

As visible in Figure 7, the device 100 communicates in bidirectional mode with a dedicated WEB Server 500, preferably in FITTPS mode.

As visible in Figure 5, the device 100 comprises a control unit 1 comprising an electronic card in which there is mounted a PIC microprocessor, a removable SD memory card and preferably an RF radio frequency data transmission/reception BT interface, preferably of the wireless type, and preferably compatible for the transmission/reception of data through the Bluetooth protocol and/or connected to a modem M provided with a SIM card for the wireless radio frequency connection. The power supply VIN of the device 100 is external, preferably by means of a power supply with wall outlet, but it is also possible to power it with a battery (so-called external "power-bank").

The control unit 1 preferably comprises an executive software FL that operates according to a fuzzy logic by implementing a fuzzy logic controller 200 shown in Figure 6. The controller 200 comprises a fuzzing interface or fuzzer 201 that transforms the clearly measured data into appropriate linguistic values, following a fuzzing procedure that transforms objective data into subjective data through a mapping of the inputs in labels of fuzzy sets in each specific reference universe, converting each input value x_t into a single pair of input value and membership function (c_ί,mi 0)) and thus the entire set is understood as the union of its individual components. The basic rules of fuzzy control are characterized by a collection of IF TFIEN fuzzy rules in which the preconditions (antecedents) and the consequents involve variables, according to this form:

R^l: IF x is A_t, ...,AND y is B_t,THEN z is C_t i = 1 ...n. where x, ..., y and z are variables representing respectively the process state variables and the control variable and Ai, ..., Bi, Ci are the values of the variables x, ..., y and z. The controller 200 comprises the inference engine 202 and a database comprises the basic rules 203. The inference engine must calculate the membership functions and must process the output of the system as a function of the input variables from the fuzzier 201 and as a function of the basic rules 203. In addition, the controller 200 is of the closed loop type in that the membership functions are also calculated as a function of the results of the previous cases. The controller 200 also comprises a defuzzer 204 adapted to convert the output linguistic values into data, in particular into the signal y.

Preferably the device 100 belongs to a plurality A1 , A2...An of devices 100 connected with the WEB Server 500 preferably wirelessly, as visible in Figure 5. Each device 100 of the plurality of devices A1 , A2...An is connected with the respective oxygen concentrator 300 of the plurality of oxygen concentrators B1 , B2...Bn.

Preferably, data processing also takes place in a dedicated partition of the server 500, where the basic rules and the inference engine integrated in each device 100 locally are replicated and reside. In this case, the system behaves as an indirect monitoring apparatus of the patient's condition and the use of the controller 200 allows this task to be managed and the optimal purity oxygen volume to be determined; this takes place by following a continuous process of acquisition of the inputs and of processing the outputs, for all the devices 100 connected to the network. Consequently, all network-connected devices 100 can draw on these resources in the fuzzification and defuzzification process, by connecting to the aforementioned WEB Server, via a connection preferably of the HTTPS type. In the connection, each device 100 feeds an existing database with the value updated to the last detection of each parameter that defines the individual rules, which are thus updated continuously and over time, for each device 100 in the network. At the end of each day, the average of each parameter is computed and this value is made available for download, to each device 100 connected in the network. The aforementioned upload and/or download connection to the WEB Server, preferably of the HTTPS type, is guaranteed by using a gateway (to which the device 100 connects wirelessly via a compatible Bluetooth interface) or via the modem M with integrated SIM. Therefore, when each device 100 is installed, it can, by connecting to said server 500, download the values of the parameter of the updated rules, without starting from the initial value defined by the single rule.

The specialist who prescribes the oxygen therapy to the patient connects to the WEB SERVER 500 to set "when" and "how much" of the latter; that is:

• to vary the hours of treatment for the patient ("when") "T_jER", i.e. , the "Time of the Therapy", at the time "i-th" t;

• to vary regulate the oxygen flow ("how much"): "F_JER' that is, the "Flow of the Therapy", at the time "i-th" t.

The parameters acquired by the device 100, for each i-th therapy time are divided into three categories:

1) "Oxygen Delivered to the Patient", abbreviated as OD {OE_F.T.P) this category accounts for the quality of the oxygen delivered to the patient as a whole and is divided into three sub-categories: OE_F, i.e. "Oxygen Flow Delivered to the Patient"; OE_T, i.e. "temperature of the oxygen delivered to the patient" and OE_P, i.e. "purity of the oxygen delivered to the patient";

2) "Environment where the patient uses the concentrator", abbreviated as "ENV"; this category accounts as a whole for the quality of the environment in which the patient takes in the oxygen and is divided into three sub-categories (AM_T.H.Q)\ AM_T, i.e. "temperature of the environment"; AM_H, i.e. "humidity of the environment"; AM_Q, i.e. "air quality of the environment";

3) "Patient's vital parameters, abbreviated as PT and divided into "i" categories: PZp., where "R_;" is the type of vital parameter (for example: SpC or Heart Rate), read by an external medical device that interfaces to the apparatus via radio-frequency communication, Bluetooth compatible with this category which accounts as a whole for the patient's clinical picture.

The parameters are acquired by the device 100 by means of sensors integrated into the device 100 and/or by means of signals inputted from the outside via the BT interface or preferably inputted directly via the DIN data connection.

The device 100 comprises a tube IN for the inlet of oxygen coming from the concentrator 300 and a tube OUT for the outlet of oxygen from the apparatus 100 towards the concentrator 300 for the delivery towards the patient.

The device 100 comprises some sensors for detecting parameters of the oxygen coming from the concentrator 300 and parameters of the environment in which the concentrator 300 and the device 100 are arranged; said detected parameters, normally of the analogue type, are an input to an SE interface of the control unit 1 for the transformation into digital signals an input to the PIC microcontroller of the control unit 1.

The device 100 then provides that some input data are entered by the specialist from the outside, for example via the WEB through the WEB Server 500 or directly by the specialist via any wireless or non-wireless interface of the device 100, because they are related to the therapy that the patient must follow:

1) i.e., the "Flow of the Therapy", at the time "i-th" t.

2) i.e., the "Flow of the Therapy", at the time "i-th" t.

The sampling of the signals inputted to the controller 200 is performed by the software FL executed by the PIC microprocessor with sampling times varying as a function of the input signal.

The value of the oxygen flow delivered to the patient, OE_F, is detected by a sensor SF, which for example measures the flow variations from one point to another of the path, integrated into the device 100, generally as an analogue value and sent to the interface SE.

For each therapy period, with duration t the rule on the oxygen flow delivered to the patient is as follows:

OEp * ti = Volume of oxygen delivered to the patient over time tp

The data item on the purity of the oxygen delivered to the patient is detected by a sensor SP, which for example measures F1O2, that is the fraction of inspired oxygen (fraction of inspired O2), that is, the percentage of oxygen inspired by a patient integrated into the device and sent to the interface SE. The sensor SP may be for example an electrochemical sensor adapted to measure a chemical reaction that creates an electrical output proportional to the percentage of oxygen inspired by the patient; the electrochemical sensor SP is arranged in the oxygen delivery path from the concentrator to the patient.

After sampling, the relative analogue signal x^z is obtained.

The fuzzy rule on the "purity of the oxygen delivered to the patient" is as follows:

IF Zmin ≤ x^z ≤ Zmax THEN THE PATIENT TAKES IN PURITY OXYGEN

If the patient takes in purity oxygen, the membership function of the purity of the oxygen delivered to the patient is calculated, as follows:

Z_min and Z_max represent the minimum and maximum value of the purity of the oxygen delivered to the patient of the concentrator 300 to which the apparatus is connected; this process is continuous and within the limits Z_min - Z_max There is a misconception that the oxygen contained in the cylinders is pure while the oxygen in the concentrators is not; some even argue that the oxygen in the cylinders, being considered as a medicament, belongs to a "higher category" than that produced by the oxygen concentrators. Whilst the oxygen contained in the cylinders is 99.5% pure and is considered a C-category drug: to obtain it, a medical prescription is required, the oxygen produced by the concentrators is 93.0% pure and a medical prescription is not necessary: they are freely available medical devices. This is not to say that the oxygen in the cylinder is better: in fact, the purity of the oxygen, if above 90%, does not produce any difference at the patient's saturation level. It is also important to point out the fact that the purity of the drug "oxygen" is equal to 99.5% not because this is a purity necessary for a therapeutic purpose, but because it is the basic purity with which the oxygen is produced for industrial and medical uses. Several clinical studies confirm that the real oxygen percentage absorbed by the patient at the level of the upper airways (nose) is comprised in a range between 30 and 40%. Therefore, even starting from an oxygen purity equal to 100%, the oxygen flow will still be mixed with the air entering the nose, therefore the actual purity will never exceed 40%. For this reason, the latest generation oxygen concentrators guarantee the same saturation achieved with the liquid oxygen cylinders. Hence, the therapy with oxygen from concentrator is the oxygen-enriched air therapy, with variable concentration according to what is stated by the supplier with a concentration of up to 90-95% and in any case never less than 82%. The standard provides for a tolerance of ± 3% with respect to the concentration declared by the manufacturer. The concentration of the oxygen from the concentrator can vary in the flow: up to 5 LPM the current instruments can guarantee an oxygen concentration typically of 90% (±3%). Each concentrator model is characterized by the operating data specified by the manufacturer in the user manual.

The minimum level Z_min is normally equal to: 90% while the maximum level Z_max is normally equal to: 96%

Another input of the controller 200 is the signal relative to the air quality of the environment where the patient takes in the oxygen, referred to as x⁹ which is measured by the sensor QA, preferably a semiconductor sensor that measures the air quality and provides the analogue signal x⁹ which is a signal representative of the volatile organic compounds (VOCs) and of the equivalent carbon dioxide (CC>2e) in the environment, i.e. a measurement that expresses the impact on the global warming of a certain amount of greenhouse gas with respect to the same amount of carbon dioxide. The rule of the fuzzy controller is:

IF Gmin £ x⁹ £ G_max THEN THE AIR QUALITY IS ADEQUATE

If the air quality in the environment is adequate, the membership function is calculated, which is as follows:

wherein:

G_min and G_max represent the minimum and maximum value of the air quality where the patient takes his therapy.

The minimum level G_min is normally equal to 400 ppm equivalent for C02e and 0 ppb isobutylene equivalent for VOC, while the maximum level G_max is normally equal to 2000 ppm equivalent for CC>2e and 1000 ppb isobutylene equivalent for VOC.

Another input of the controller 200 is the signal relative to the temperature of the oxygen delivered to the patient ( x^ot ), deducted from the value of the reading of the temperature sensor ST integrated into the apparatus. The apparatus 100 detects, in analogue or digital, the temperature value, in °C, of the oxygen passing through the flow sensor integrated into the apparatus. In the event that the temperature value is below a specified reference threshold OT_min (e.g. 15 °C), the apparatus detects this condition as a confirmation that the temperature is too low. In the event that the temperature value is above a reference threshold indicated as OT_max (e.g. 40 °C), the system detects this condition as a confirmation that the temperature is too high. The rules are as follows:

IF x^ot < 0¾_in THEN THE TEMPERATURE OF THE OXYGEN IS TOO LOW

Knowing that the oxygen temperature is too low is useful because too cold oxygen creates discomfort for the patient and therefore contributes negatively to the adherence to therapy.

IF x^ot > OT_max THEN THE TEMPERATURE OF THE OXYGEN IS TOO HIGH

Knowing that the oxygen temperature is too high is useful because too hot oxygen creates discomfort for the patient and therefore contributes negatively to the adherence to therapy. In the event that the oxygen temperature is too low or too high, the temperature membership function x^ot is calculated which is as follows:

wherein:

OT_min and OT_max represent the minimum and maximum value of the temperature of the oxygen delivered to the patient at the time ti.

The minimum level OT_min is normally equal to the environmental temperature, while OT_max it cannot exceed 6°C above the environmental temperature.

Another input of the controller 200 is the signal relative to the temperature of the environment where the patient takes in the oxygen ( x^at ), acquired from the value of the reading of the temperature sensor AT integrated into the apparatus. In the event that the temperature value is below a specified reference threshold AT_min (e.g. 15 °C), it detects this condition as a confirmation that the temperature is too low. In the event that the temperature value is above a reference threshold indicated as OT_max (e.g. 40 °C), the system detects this condition as a confirmation that the temperature is too high. The rules are as follows:

IF x^at < A¾_in THEN THE TEMPERATURE OF THE ENVIRONMENT IS TOO LOW and thus x^at™m = o.

Knowing that the temperature of the environment is too low is useful because a too cold environment creates discomfort for the patient and therefore contributes negatively to the adherence to therapy.

IF x^at > AT_max THEN THE TEMPERATURE OF THE ENVIRONMENT IS TOO HIGH and thus X^atmax 1

Knowing that the temperature of the environment is too high is useful because the too hot environment creates discomfort for the patient and therefore contributes negatively to the adherence to therapy. In the event that the temperature of the environment is too low or too high, the membership function of the temperature x^at is calculated, which is as follows:

wherein:

AT_min and AT_max represent the minimum and maximum value of the temperature of the environment where the patient takes in the therapy, which vary as a function of the value ^x _{t ax}’ ^which is the value of the maximum air quality reachable in the place where the patient is taking the therapy, at the time W after the patient has placed the concentrator in a certain point of his home. Another input of the controller 200 is the signal relative to the humidity of the environment, where the patient takes in the oxygen ( x^h ) which is acquired from the value of the reading of the humidity sensor SH integrated into the apparatus. The apparatus 100 detects a humidity value, in percentage. In the event that the relative humidity value is above a reference threshold indicated as H_max (e.g. 60%) the system detects this condition as a confirmation that the humidity of the environment is too high.

The rule is as follows: THEN THE HUMIDITY OF THE ENVIRONMENT IS TOO HIGH and

therefore it follows x^h™*^x =1.

If the humidity of the environment is too high, the membership function of the input x^h is calculated which is as follows:

Where m^h is the centre of the bell function and is calculated in the following way:

a^h is the width of the bell function, and is calculated in the following way:

As a result, the width and the centre of the bell change as a function on the value of the temperature of the environment or of the temperature of the oxygen delivered at the time

Imax-

Preferably the membership function of is as follows:

Where:

is the dimensionless coefficient applied to the condition "the humidity of the environment is too high", which follows the following course:

The dimensionless coefficient y^hma represents a weight and has a value comprised between 0 and 1, associated with an excessively high humidity (i.e. above H_max ). The initial value of

(equal to 0.5) is increased or decreased by 0.05 as a function of the value of the temperature of the environment or of the temperature of the oxygen delivered at the time t_max.

Preferably, the caregiver can enter subjective data on the patient's condition that can be considered as input variables having value 0 or 1 respectively if they are not present or if they are present.

For example, the data item that the patient has eaten can be considered as a variable x^F that assumes value 1 if the data item that the patient has eaten has been entered otherwise it assumes value 0. The membership function of the input x^F , "the patient has eaten" is as follows: patient has eaten" is true rwise

Again, the data item that the patient has taken a certain drug can be considered as a variable x^G that assumes value 1 if the data item that the patient has taken a certain drug has been entered otherwise it assumes value 0. The membership function of the input x^G "the patient has taken a certain drug" is as follows: if the affirmation "the patient has taken a certain drug" is true

0, otherwise

The data item on the "patient's weight" can be considered as a variable x^E that assumes value 1 if the data item on the patient weight has been entered, otherwise it assumes value 0.

The data item that the patient feels pain due to the therapy can be considered as a variable x^A that assumes value 1 if the data item that the patient feels pain due to the therapy has been entered otherwise it assumes value 0. The membership function of the input x^A, "the patient feels pain due to the therapy" is: if the affirmation "the patient feels pain due to the therapy' is true 0, otherwise

The data item that the patient feels pain for another reason can be considered as a variable x^B that assumes value 1 if the data item that the patient feels pain for another reason has been entered, otherwise it assumes value 0. The membership function of the input X^s, "the pain of the patient is due to reason B" is as follows: if the affirmation "the pain of the patient is due to reason B" is true

0, otherwise

Preferably, once the input signals have been received and the various values of the variables or digital signals x have been calculated, the functions m(c) referred to above and represented below as m{c{), for display economy, are weighed to determine, alternatively and as a function of the needs for optimization of the therapy by the specialist, the "target value of F^_CI", that is the "oxygen flow that optimizes the long-term therapeutic compliance of the patient" for the same time, or the "target value of T[_JCI ", that is "oxygen delivery time that optimizes the long-term therapeutic compliance of the patient" for the same flow. In particular, the signal outputted from the controller 200 is the signal y given by the weighted average value of the values^(xi):

where å\s the summation of all the membership functions m(c_£) relative to said inputs x_t or only some of them if there are no inputs and å_max is the value of the summation where the membership functions are at the maximum value.

Once the value y is determined, the Real POV for the Patient (RPOV) is obtained from the device 100, calculated as follows:

RPOV = OEF * (t₁ — t₀) * y

Where (t_j - t₀) represents the period of time of use of the concentrator and/or all the times the oxygen flow is other than zero.

The apparatus then compares RPOV with the optimal one (OPOV), calculated by applying the following formula:

OPOV — OEF_TER * T_TER

Where: OEF_TER is the oxygen flow prescribed by the specialist for the time of the therapy

TTER -

If the difference between OPOV and RPOV is below a certain threshold CS (whose value is for example comprised between 5% and 10% of OPOV), the device 100 does not carry out a subsequent monitoring but it resumes monitoring at the next inhalation of oxygen of the patient, that is, at the next therapy.

In the event that said difference exceeds the threshold CS, the device 100 continues to monitor the oxygen in subsequent instants of time ti for i ranging from 1 to n, for a period Tcs of time set by the specialist and sends the calculated values RPOV to the WEB Server 500 which comprises a memory where a database is installed with the data received from all the single monitoring devices 100 of the plurality of monitoring devices A1 , A2...An If the value RPOV always remains above said threshold CS with respect to the value OPOV for the entire period of time T cs, the monitoring device sends the values RPOV to the WEB Server 500 so that the specialist can see them and intervene, for example by changing the values OEF_TER or T_TER. With the monitoring system in accordance with the invention, the specialist can follow a large number of patients simply by connecting to the WEB Server 500 and verifying the course of the single therapies set for patients and modifying them.

In addition, the specialist, always in the event that the value RPOV always remains above said threshold CS with respect to the value OPOV for the entire period of time Tcs, may modify the value of said threshold CS.

The device 100 also contributes to achieving the non-secondary objective of optimizing the patient's long-term therapeutic compliance performance index (LTCl), thus calculated, at the time t following the time to:

When the device 100 is first switched on (at the time to), it connects to and downloads the data of the therapy uploaded to the WEB-Server 500 unless said data are entered directly by the specialist via a wireless interface or via a DIN input cable. Afterwards, the device can work even without being connected to the WEB-Server, with the limitation that, in order to exchange the coefficients relative to the fuzzy logic, it must communicate in bidirectional mode with the WEB-Server.

Expressed in a formula, then the device 100, at the time t₂, subsequent to the instant of time ti, as a function of the course of the therapy time t_t determines:

1) the flow of purity oxygen that optimises the long-term therapeutic compliance of the patient, with the same time: ft 2 _ ^rTER

^{LTCI ~} LTCI_ti

2) the therapy time that optimizes the long-term therapeutic compliance of the patient, with the same flow:

In this way, the device 100 optimizes the intake of the Purity Oxygen Volume, that is, the Purity Oxygen Volume (POV) of the patient with chronic respiratory pathology and connected to a stationary oxygen concentrator at his home, since it allows the specialist to modify (at time t₂, based on the results of the therapy at the time t_j) the optimal POV based on the dynamic comparison between the so-called RPOV, that is, the real one for the patient and the optimal POV. The device 100 also contributes to achieving the non secondary goal of optimizing the so-called "long-term compliance performance index" of the patient (LTCI), with the combined result of optimizing the quality of his life, despite the patient's chronic pathology, with a result that is not otherwise achievable with other apparatuses currently on the market of the long-term oxygen therapy.

Preferably, the WEB Server 500 receives from each device 100 of the plurality of networked devices A1, A2...An the monitored parameter values, at the end of each therapy session, for example for the n-th device 100 An, the WEB Server 500 receives the following values:

• the oxygen flow delivered to the patient, at the i-th time

• the temperature of the oxygen delivered to the patient at the i-th time

• the purity of the oxygen delivered to the patient at the i-th time

• the temperature in the surrounding environment, where the patient takes in the oxygen at the i-th time {

• the humidity in the surrounding environment, where the patient takes in the oxygen at the i-th time

• the air quality of the surrounding environment, where the patient takes in the oxygen at the i-th time and preferably

• the vital parameters of the patient connected to the apparatus at the i-th time

• subjective data on the patient condition (X_f).

• the patient's intake of drug (X_g).

• the patient's weight (X_e).

• The data item representative of the fact that the patient feels pain due to therapy (X_a). The data item representative of the fact that the patient's pain is due to reason

B (X_h).

The specialist for the n-th patient taking in the oxygen from the n-th concentrator 300 Bn connected to the respective n-th device 100 An (but for each device 100 of the plurality of networked devices A1, A2...An, and therefore for each patient who is treating and to whom he prescribes home oxygen therapy with stationary oxygen concentrator) sets the parameters via the WEB in response to the data sent by the n-th device

100 An.

The n-th device 100 An, preferably in HTTPS mode, downloads the data relative to therapy uploaded by the specialist from the WEB SERVER 500.

At the beginning of the therapy, the n-th device 100 An connects to the WEB SERVER 500 and downloads these values, to calculate, locally, the value of OPOV by applying the following formula:

This is done by following a continuous process of local acquisition, for each device (and therefore, for each patient) of the inputs, of sending to the WEB SERVER 500 and of processing the outputs: in the connection, each device 100 feeds an existing database with the value updated to the last detection of each parameter that defines the individual rules, consequently, updated continuously and over time, for each networked device 100. The device 100, allows to modify the values set by the specialist and

therefore the optimal POV so as to identify the best value RPOV for the specific patient who uses a specific concentrator and thus obtain an LTCI as close as possible to the maximum unit value (100%) and this for each period of the oxygen therapy set by the specialist who prescribed home treatment with the oxygen concentrator.

At the end of each therapy, at the time "i", the n-th device 100 An sends to the WEB SERVER 500 the following values:

Where (t_£ - t^) represents the "concentrator usage time" and/or all the times the Oxygen Flow is other than zero.

In addition, the specialist, always in the event that the value RPOV·¹ always remains above said threshold CSⁿ with respect to the value OPO Vⁿ for the entire period of time Tcs, can modify the value of said threshold CSⁿ also based on the comparison of the parameters detected by the monitoring device An with the parameters detected by the other devices A1 , A2...An-1 that are stored in the database within the WEB Server 500.

Especially at times like the current ones, with COVID, the present invention allows to break down the physical barriers of taking charge of the chronic patient consisting in the distance between specialist and assisted person, the latter having to strictly adhere to the therapeutic indications of a specialist (in particular with regard to the hours of treatment and to the regulation of the oxygen flow) and having to contact the latter for monitoring the treatment and for renewing the therapeutic plan (annual validity), but (the patient) being at a very far distance.

In particular, the system according to the present invention entails the following advantages:

• it improves the therapeutic compliance of the patient;

• it provides the specialist, as a reference parameter, with the volume of oxygen taken by the patient and not the flow;

• it indicates to the patient a purity oxygen volume personalised to his specific needs, who, given the pathology, has a lower sensitivity with respect to the real flow of assimilated oxygen, which he otherwise would tend to underestimate;

• it ensures the effective monitoring of the therapeutic compliance between specialist visits, which can also be several months apart, providing all the actors involved in the process and authorised, possibly within a telemedicine platform, with a system accessible remotely from an operations centre;

• it promotes the use of the concentrator at flows lower than or equal to 5/6 LPM, as an alternative to the more expensive liquid oxygen cylinder, continuously accounting for the patient's therapeutic compliance;

• it monitors the environment where the patient takes in the oxygen, which must be purified to achieve an optimal level of filtration of the concentrator;

• it monitors the course of the physiological (and/or subjective) parameters of the patient, as an effective measure of the course of the therapy;

• it employs a fuzzy logic, as an element for the whole of the system's artificial intelligence.

Claims

1. Device (100) for monitoring the oxygen inhaled by a user and produced by an oxygen concentrator, said device comprising:

- means (SF) for detecting the oxygen flow,

- means (SP) for detecting the purity of the oxygen,

- means (ST) for detecting the oxygen temperature,

- means (SH) adapted to detect the humidity of the environment in which the concentrator is arranged,

- means (QA) adapted to detect the air quality of the environment in which the concentrator is arranged,

- means (ST) adapted to detect the temperature of the environment in which the concentrator is arranged,

- a control unit (1) provided with a microprocessor and with a memory and adapted to receive the signals coming from the totality of said means, characterized in that said control unit (1 ) is adapted to determine the real purity oxygen volume (RPOV) in response to the signal coming from said means for detecting the oxygen flow and as a function of the other signals coming from the other means and received in the period of time (t - t₀) in which the oxygen flow remains other than zero.

2. Device according to claim 1 , characterized in that said control unit comprises an executive software (FL) installed in said memory (SD), said software operating in accordance with a fuzzy logic in which basic rules (201) are defined and the membership functions are calculated (μ(x^at)μ(x^z)μ(x^ot)^(x⁹ μ(x^{h '}) for all said other signals inputted to said control unit, said control unit being adapted to calculate the membership functions (μ c^a),m(c⁹)) relative to all said other signals, the real purity oxygen volume (RPOV) being determined in response to the signal coming from said means for detecting the oxygen flow and as a function of the weight (y) of the membership functions relative to all said other signals coming from the other means in the period of time (t₁ - t₀) in which the oxygen flow remains other than zero.

3. Device according to claim 2, characterized in that it comprises means (BT, DIN) for receiving data on the user's condition that can be inserted from the outside and can be stored in said memory (SD), said data being treated by said software as input signals, the membership function

relative to each of said data assuming a value 1 or 0 depending on the presence or absence of the data item, the real purity oxygen volume (RPOV) being determined in response to the signal coming from said means for detecting the oxygen flow and as a function of the weight (y) of the membership functions

relative to all said other signals coming from the other means and of the membership functions ((m(c^r), m(c^B), m(c^a), m(c^A)) relative to said data in the period of time (t_j - t₀) in which the oxygen flow remains other than zero.

4. Device according to claim 3, characterized in that it comprises an interface (BT) for receiving data on the therapy that the user to whom the oxygen is inhaled must follow, said data concerning the flow of optimal purity oxygen and the optimal time for its administration so as to determine the volume of optimal purity oxygen (OPOV), said device making a comparison between the optimal purity oxygen volume and the real purity oxygen volume and repeating said comparison in subsequent instants of time for a given period of time (Tcs) if the difference between the optimal purity oxygen volume and the real purity oxygen volume exceeds a given threshold (CS).

5. Apparatus comprising an oxygen concentrator (300) and a device (100) for monitoring the oxygen inhaled by a user and produced by said oxygen concentrator as defined in any one of claims 1 to 4, said apparatus comprising means (400) for the removable connection of said device with said oxygen concentrator.

6. Apparatus according to claim 5, characterized in that said means for the removable connection of said device with said oxygen concentrator are suction cups.

7. Apparatus according to claim 6, characterized in that said suction cups comprise a main part (401) attachable to a face (102) of said concentrator and a tightening screw (402) for fixing said device to the oxygen concentrator.

8. System comprising a plurality of oxygen concentrators (300, B1 , B2...Bn) respectively connected to a respective plurality of monitoring devices (100, A1 , A2,...An) of the oxygen inhaled by a respective plurality of users and produced by the respective plurality of oxygen concentrators, said system comprising at least one dedicated server (500) comprising means (BTS) for exchanging data with each monitoring device of said plurality of monitoring devices, each of said monitoring devices of the plurality of monitoring devices being defined as in any one of claims 1 to 4.

9. System according to claim 8, characterized in that said server comprises n interface (BTS) for sending data to each device of the plurality of devices on the therapy that the user to whom the oxygen is inhaled must follow, said data concerning the flow of optimal purity oxygen and the optimal time for its administration so as to determine the optimal purity oxygen volume (OPOV), each device performing a comparison between the optimal purity oxygen volume and the real purity oxygen volume (RPOV) and repeating said comparison in subsequent instants of time for a given period of time (Tcs) if the difference between the optimal purity oxygen volume and the real purity oxygen volume exceeds a given threshold (CS), each device sending the data item on the real purity oxygen volume calculated and on the comparison between the optimal purity oxygen volume and the real purity oxygen volume to said server so that the specialist, by connecting to the server and based on the data received, can maintain or change said therapy.

10. System according to claim 9, characterized in that said server comprises an interface (BTS) for sending data to each device of the plurality of devices on the therapy that the user to whom the oxygen is inhaled must follow, said data concerning the flow of optimal purity oxygen and the optimal time for its administration so as to determine the optimal purity oxygen volume (OPOV), each monitoring device of said plurality of monitoring devices being adapted to send to said server all the data detected by the totality of the detection means so that the specialist, by connecting to the server, can maintain or change said threshold date (CS) based on a database containing all the data detected by the totality of the detection means of each monitoring device of said plurality of monitoring devices.