DEVICE FOR AUTOMATING OXYGEN FLOW CONTROL, PROCESS AND USES

Description

1 / 20 “DEVICE FOR AUTOMATING OXYGEN FLOW CONTROL, PROCESS AND USES”

[01] The present technology refers to a device for automating oxygen flow control, the automation process performed by the device, and its uses. The device connects a pulse oximetry sensor to a microcontroller, capable of controlling a motor that actuates the valves of a flowmeter connected to an oxygen source. The process of the present technology includes the use of broker and node-red, which allow automating the opening and closing of the flowmeter valve in order to correct the peripheral oxygen saturation (SpO2) of a patient. The present technology can be used to automate the opening and closing process of flowmeter valves used in low-flow oxygen therapy. The main advantages of the technology include connectivity with other devices, its small size, the use of flowmeters already in hospital networks, the ease of construction or installation of the device, and the possibility of continuous use.

[02] Respiratory system diseases are one of the main reasons for hospital admission, being responsible for a large proportion of deaths. Among respiratory system diseases, hypoxemia is a respiratory condition in which the level of oxygen necessary for the proper functioning of an individual's body is low, identified by a reduction in arterial oxygen pressure (PaO2) and peripheral oxygen saturation (SpO2). Because it is a clinical emergency, it is necessary to provide supplemental oxygen (O2) immediately, a therapy called oxygen therapy. Petition 870250004190, dated 17 / 01 / 2025, page 10 / 199 2 / 20

[03] Oxygen administration requires intensive monitoring due to the risks that can be caused by insufficient or excessive supply. Excess O2 administration can potentiate hyperoxemia, causing serious lung damage, in addition to the possibility of carbon dioxide (CO2) retention and elevated arterial CO2 pressure levels (PaCO2), especially in patients with chronic obstructive pulmonary disease. Oxygen therapy should not be applied solely based on the patient's complaint of dyspnea; careful evaluation and titration at short intervals are necessary, considering all the patient's vital signs and respecting a target SpO2. Therefore, oxygen flow adjustments in oxygen therapy should be made cautiously based on the patient's oximetry and blood gas analysis, aiming for gradual weaning until adequate SpO2 is achieved in room air.Considering that an individual's O2 needs change over time, and that most healthcare institutions adjust O2 flow manually, the direct and continuous intervention of a qualified professional is necessary, using a pulse oximeter to assess the patient's SpO2, thus verifying the need for oxygen flow titration in oxygen therapy to achieve a target SpO2. However, manual flow adjustments make therapeutic efficiency dependent on continuous monitoring by a qualified professional to reassess SpO2 and make possible periodic adjustments to the oxygen flow. In the case of patients treated in out-of-hospital settings, such as home care services, the patient may remain for several hours or days with the same O2 flow titration, becoming susceptible to the harmful effects of inadequate supply. Petition 870250004190, dated 17 / 01 / 2025, page 11 / 199 3 / 20

[04] Some patients may alternate between hypoxemia and hyperoxemia. Among the possible causes of this alternation are chronic lung diseases, such as asthma, which can cause hypoxemia. If the patient is treated with excess oxygen, they may develop hyperoxemia. If, on the other hand, the oxygen supply is drastically reduced, the asthmatic patient may quickly revert to hypoxemia. In this situation, a technology capable of meeting the needs of patients who may alternate more frequently between different SpO2 levels becomes necessary.

[05] In some severe cases, a patient may have moderate or severe respiratory failure, making high-flow oxygen therapy important. This respiratory support modality provides oxygen in controlled concentrations at high flow rates through a heated and humidified nasal cannula. On the other hand, some patients have a greater degree of autonomy to breathe, making it more convenient for weaning the patient if they do not receive high oxygen flow rates. In these cases, clinical intervention with oxygen therapy is done by providing supplemental O2 to the patient and can be adjusted by varying the O2 flow rate using a flowmeter, which in the conventional modality is graduated up to 15 L / min and can be used in various interfaces (masks, catheters, or other specific devices).Each of these devices has specific application characteristics, mainly considering the guarantee of the Inspired Oxygen Fraction (FiO2). In the case of simple catheters and masks, it can be stated that they do not guarantee a high FiO2, because, depending on the patient's clinical characteristics, such as respiratory rate, tidal volume, and other clinical parameters, there may be variation in the dilution of O2 with ambient air. Therefore... Petition 870250004190, dated 17 / 01 / 2025, page 12 / 199 4 / 20 In this way, oxygen therapy is classified as "low-flow" therapy and should be titrated based on the needs of each patient.

[06] One of the difficulties in controlling SpO2 is having a technological device that adequately adjusts to the values ​​measured by the sensor, which can provide inaccurate data. Some of these inaccuracies are generated by wear and tear on the sensor itself, by low blood perfusion, as in patients with hypothermia, by excessive patient movement, by greater light absorption by the skin due to its color, by the use of vasoconstrictor medications, which reduce peripheral blood flow, or even by failures in saturation recording, resulting in measurements above 100%, in addition to compression of blood vessels. Considering that sensors capable of handling all these scenarios are difficult to produce or obtain, an alternative is to modify the device or the data processing of the sensor to ensure the obtaining of adequate SpO2 results.

[07] In this sense, in the state of the art there are some documents that reveal technologies aimed at automating oxygen flow in oxygen therapy.

[08] Patent document AU2015904621A, with a priority date of 10 / 11 / 2015, entitled “Method, apparatus and system for automatically controlling inspired oxygen delivery”, describes a method for automatically controlling the delivery of inspired oxygen, which includes: receiving signals representing a plurality of peripheral oxygen saturation (SpO2) values ​​in a patient's blood, generating control values ​​based on the received SpO2 values ​​and a target SpO2 value; and generating inspired oxygen concentration (FiO2) values ​​based on the control values ​​and the reference inspired oxygen concentration values. Petition 870250004190, dated 17 / 01 / 2025, page 13 / 199 5 / 20 However, AU2015904621A uses a system that mixes air with oxygen, requiring additional equipment for its operation, which increases the complexity of the technology, limiting its construction, transport, or installation. Furthermore, AU2015904621A requires an extensive process with multiple parameter controls, which increases the probability of errors in the SpO2 control process.

[09] Patent document CA3000522A1, with priority date 05 / 10 / 2015, entitled “Method for delivery of breathing gas to a patient and system for performing same ”, describes a process comprising delivering a flow of breathing gas to a patient, which involves measuring the patient’s oxygen saturation level, determining the patient’s respiratory rate, automatically adjusting the inspired oxygen fraction of the breathing gas based on the patient’s measured oxygen saturation level and a breathing gas flow rate setpoint, and automatically adjusting the breathing gas flow rate setpoint based on the patient’s determined respiratory rate.However, CA3000522A1 has a highly complex controller structure and requires components such as air fans to dispense airflow, which increases the complexity of the technology when producing or handling it, in addition to the technology being suitable for high-flow therapies rather than low-flow therapies.

[010] Patent document GB2508897, with a priority date of 14 / 12 / 2012, entitled “Automatic oxygen flow regulator using a pulse oximeter”, describes a pulse oximeter combined with an oxygen flow controller comprising a control knob for manually adjusting the oxygen flow rate, power cord, pulse oximetry sensor, pressure switches, flow valve and an actuator, PID (proportional, integral and derivative) controller that controls the means of. Petition 870250004190, dated 17 / 01 / 2025, page 14 / 199 6 / 20 valve actuation. However, GB2508897 makes use of a large number of devices, such as manual control buttons, actuators or PID controllers, which makes the technology more complex with a greater number of components to be built. In addition, PID controllers require high energy consumption for processing for systems with batteries that provide low power.

[011] Patent document CN116807467A, with a priority date of 12 / 07 / 2023, entitled “Blood oxygen saturation monitoring and early warning system and method based on finger clip type pulse oximeter”, describes a method for monitoring and providing early warning of oxyhemoglobin saturation based on a finger clip type pulse oximeter. The method comprises the steps of obtaining historical oxyhemoglobin saturation detection data from a monitored patient, calculating the average value of this historical data, and analyzing the standard reference range of oxyhemoglobin saturation. Based on the average value of the historical data and the standard reference range, the system calculates the early warning value of blood oxygen saturation.However, CN116807467A does not address the correction of SpO2 values, but rather their prediction, where the oxyhemoglobin value and its average are not used to adjust oxygen flows, which could be increased, reduced, or kept constant as needed by the patient.

[012] In general, the technologies for automating oxygen flow control in low-flow oxygen therapy presented in the state of the art do not jointly solve problems such as: providing oxygen without the need for additional equipment to mix air with oxygen, being low-flow, having a small number of parts, and being able to work for various types of patients, being adaptable to various oxygen sources. Petition 870250004190, dated 17 / 01 / 2025, page 15 / 199 7 / 20

[013] In the state of the art, no device for automating oxygen flow for low-flow oxygen therapy was found, with a simple automation process comprising an input for a pulse oximetry sensor, a microcontroller, a power source, batteries, a broker, a drive, a node-red, a display, a motor, a flowmeter, and a support for an oxygen source. The process allows correction of SpO2 values ​​by controlling a valve that allows oxygen to enter the device. The present technology simultaneously offers the following advantages: connectivity with other devices, low dimensionality, use of flowmeters already used in hospital networks, monitoring of parameters such as oxygenation and heart rate, obtaining accurate and rapid results, and easy construction or installation. BRIEF DESCRIPTION OF THE FIGURES

[014] Figure 1 shows, in a non-limiting manner, the device for automating oxygen flow control, comprising an input for the pulse oximetry sensor (1), a microcontroller (2), a display (5), a drive (6), a potentiometer (13), a voltage module (14), connection points and cable organization (15) and a base (16).

[015] Figure 2 shows, in a non-limiting way, the process flowchart for automating oxygen flow control, where block (Bc1) represents sending the SpO2 value obtained through the input to a pulse oximetry sensor (1) to the microcontroller (2), block (Bc2) represents a broker, block (Bc3) represents the node-red, block (Bc4) represents the display (5), block (Bc5) represents the measurement of the average SpO2 by the microcontroller (2), block (Bc6) represents clearing the microcontroller memory (2), block (Bc7) represents checking if the value of Petition 870250004190, dated 17 / 01 / 2025, p. 16 / 199 8 / 20 SpO2 is within the expected value, block (Bc8) represents the categorization between high and low SpO2 value, block (Bc9) represents a new transmission of the SpO2 value obtained through the input to a pulse oximetry sensor (1) to the microcontroller (2), where this transmission will be done recurrently aiming at stabilizing the SpO2 value or activating the motor (7), block (Bc12) represents a new verification of the SpO2 value, block (Bc13) represents the restart of the process, if the SpO2 value is within the expected range, block (Bc14) represents the opening of the valve (12).1) By activating the motor (7), block (Bc16) represents the restart of the process after activating the motor (7), block (Bc17) represents a new transmission of the SpO2 value obtained through the input to a pulse oximetry sensor (1) to the microcontroller (2), where this transmission will be done recurrently aiming at stabilizing the SpO2 value or activating the motor (7), block (Bc20) represents a new verification of the SpO2 value, block (Bc21) represents the closing of the valve (12.1) by activating the motor (7) and restarting the process, block (Bc22) represents the restart of the process, if the SpO2 value is within the expected range.

[016] Figure 3A shows, in a non-limiting way, the flowmeter (8), the valve (8.1), the support (12) formed by a larger cylinder (12.1) and a smaller cylinder (12.2).

[017] Figure 3B shows, in a non-limiting way, a motor (7), a flowmeter (8), an oxygen source (9) and the support (12).

[018] Figure 4 shows, but is not limited to, batteries (4), the back of the potentiometer (13) and a base (16).

[019] Figure 5 shows, but is not limited to, the input for a pulse oximetry sensor (1), a microcontroller (2), a display (5), a drive (6), Petition 870250004190, dated 17 / 01 / 2025, page 17 / 199 9 / 20 a motor (7), an oxygen source (9), a support (12), a potentiometer (13), a voltage module (14), connection points and cable organization (15), a base (16), a computer (18), test tube (19) and tubing (20).

[020] Figure 6 shows a graph with test results in situation 1, where a case of hypoxemia (SpO2 simulated at 82% by the potentiometer (13)) is corrected by the device until the target SpO2 is reached.

[021] Figure 7 presents a graph with test results in situation 2, where a case of hypoxemia (SpO2 simulated at 87% by the potentiometer (13)) is corrected by the device until the target SpO2 is reached.

[022] Figure 8 presents a graph with test results in situation 2, where a case of hypoxemia (SpO2 simulated at 88% in potentiometer (13)) and hyperoxemia (SpO2 simulated at 97% in potentiometer (13)) both cases are corrected by the device until the target SpO2 is reached. DETAILED DESCRIPTION OF THE TECHNOLOGY

[023] The present technology refers to a device for automating oxygen flow control, the automation process performed by the device, and its uses. The device connects a pulse oximetry sensor to a microcontroller, capable of controlling a motor that actuates the valves of a flowmeter connected to an oxygen source. The process of the present technology includes the use of broker and node-red, which allow automating the opening and closing of the flowmeter valve in order to correct the peripheral oxygen saturation (SpO2) of a patient. The present technology can be used to automate the opening and closing process of flowmeter valves used in low-flow oxygen therapy. The main advantages of the technology include connectivity with other devices, its low dimensionality, and the use of Petition 870250004190, dated 17 / 01 / 2025, page 18 / 199 Advantages include the 10 / 20 flowmeters already used in hospital networks, the ease of construction or installation of the device, and the possibility of continuous use.

[024] The device for automating oxygen flow control is characterized by the microcontroller (2), powered by the source (3) and the battery (4) through the voltage module (14), sending a signal from the input to a pulse oximetry sensor (1) to a display (5), to a buzzer (17) and to a drive (6), which is connected to a motor (7) that is connected to a flowmeter (8) through a support (12), where the flowmeter (8) is connected to an oxygen source (9) and to the support (12) formed by two hollow cylinders connected in such a way that the larger cylinder (12.1) fits into the valve (8.1) of the flowmeter (8) and the smaller cylinder (12.2) fits into the motor (7), and a potentiometer (13).

[025] With the data obtained from the input to a pulse oximetry sensor (1), it is possible to send data to a microcontroller (2), which will perform the data processing. The power supply (3) ensures that the circuit is properly energized and the battery (4) ensures that the technology continues to function, even after a possible power outage, considering that a patient needs the equipment to be on to breathe. Data on the evolution of a patient's SpO2 are immediately displayed on the screen (5). The drive (6) has the role of sending signals from the microcontroller (2) to the motor (7), making it function properly. The flowmeter (8), properly fitted to the motor (7) through the support (12), has a valve (8.1) that can be adjusted to allow increasing or decreasing the flow of gas coming from an oxygen source (9).The potentiometer (13) allows the input current of the pulse oximetry sensor (1) to be changed manually, enabling the oxygen flow to be changed manually, or it allows the simulation of a patient's SpO2 for study and research purposes, if applicable. Petition 870250004190, dated 17 / 01 / 2025, page 19 / 199 11 / 20 a computer (18) with the SpÜ2 value of a patient sends signals to the potentiometer (13) which undergoes changes that are identified as variations in the patient's SpÜ2. In this way, with easily acquired electronic components, dimensionality and connectivity, it is possible to build a device capable of automating the oxygen flow control for low-flow oxygen therapy.

[026] The process for automating oxygen flow control, using the low-flow oxygen therapy automation device, is characterized by comprising the following steps: a) Send the peripheral oxygen saturation (SpO2) value obtained at a frequency of up to 30 times per second through the input to a pulse oximetry sensor (1) represented by block (bc1) to a microcontroller (2), which comprises a display (5), which is associated with block (bc4), and a Broker (10) represented by block (bc2) connected to a node-RED (11); b) Restart the process from step “a”, activating audible warning signals via the buzzer (17) and visual signals via the display (5), if the SpO2 value is below 30% or above 100%; c) Calculate the mean Mspo2 of SpO2 over a time interval between t1=5s and t2=60s, as represented by block (Bc5); d) Clear the microcontroller memory variables (2), as shown in block (bc6), restarting the process from step “a”, if the condition 90% < Mspo2 < 96% is met; e) Check if the SpO2 value follows the condition 90% < SpÜ2 < 96%, if Mspo2 < 90% or Mspo2 > 96%, as represented by block (Bc7); Petition 870250004190, dated 17 / 01 / 2025, page 20 / 199 12 / 20 f) Clear the microcontroller memory variables (2), as shown in block (bc6), restarting the process from step “a”, if the SpO2 checked in step “e” satisfies the condition 90% < SpO2 < 96%; g) Categorize in block (Bc8) the SpO2 as low if its value is less than 90% and high if its value is above 96%; h) Send the SpO2 value through the input to a pulse oximetry sensor (1), represented by block (bc9), to a microcontroller (2) up to 20 times, if the SpO2 value has been categorized as low in step “g”, respecting a time of up to 5 seconds between each sending of the SpO2 value, repeating the SpO2 categorization of step “g” of block (Bc8) in each sending of SpO2 to the pulse oximetry sensor (1); i) Restart the process from step “a”, if the SpO2 in step “h” satisfies the condition 90% < SpO2 < 96%; j) Activate the motor (7) by sending a signal from the microcontroller (2) to the module (6) and then to the motor (7), which is connected to the flowmeter (8) by means of the support (12), opening the valve (8.1) of the flowmeter (8), if the SpO2 value has been categorized as low in step “g” up to 20 times, restarting the process from step “a”, where the valve (8.1) is opened following the proportional control action (P) with the proportional action error calculated by the difference between the expected SpO2 value within the range 90% < SpO2 < 96% with the obtained SpO2 value; Petition 870250004190, dated 17 / 01 / 2025, page 21 / 199 13 / 20 k) Send the SpÜ2 value through the input to a pulse oximetry sensor (1), represented by block (bc17), to a microcontroller (2) up to 20 times, if the SpO2 value has been categorized as high in step “g”, respecting a time of up to 5 seconds between each sending of the SpÜ2 value, repeating the SpÜ2 categorization of step “g” of block (Bc8) in each sending of SpO2 to the pulse oximetry sensor (1); l) Restart the process from step “a”, if the SpO2 in step “k” satisfies the condition 90% < SpO2 < 96%; m) Activate the motor (7) by sending a signal from the microcontroller (2) to the module (6) and then to the motor (7), which is connected to the flowmeter (8) by means of the support (12), closing the valve (8.1) of the flowmeter (8), if the SpO2 value has been categorized as high in step “g” up to 20 times, restarting the process from step “a”, where the valve (8.1) is closed following the proportional control action (P) with the error of the proportional action calculated through the difference between the expected gas concentration value and the obtained gas concentration value.

[027] In step “a”, SpO2 is obtained at a frequency of up to 30 times per second, which ensures continuous monitoring with each change in a patient's condition. The microcontroller (2) processes the SpO2 values ​​and sends them to a display (5) that allows visualization of the data and to a Broker (10) that allows communication with the input for a pulse oximetry sensor (1) and the motor (7). The Broker (10) is connected to the Notered (11) through which, via a graphical interface, it is possible to view the data obtained in the Broker (10). Petition 870250004190, dated 17 / 01 / 2025, page 22 / 199 14 / 20

[028] In step “b”, measurement errors from the pulse oximetry sensor (1), which may be worn or inaccurate, or some disconnection caused by a user when removing the pulse oximetry sensor (1), may cause the SpO2 value to be above 100% or below 30%, which constitute measurement errors. To prevent this error from propagating to other stages of the process, and to prevent the oxygen flow from increasing or decreasing improperly, step “a” is reset and audible warning signals via the buzzer (17) and visual signals via the display (5) are activated.

[029] In step “c”, the average SpO2 is calculated and used as a filter to prevent point deviations in the SpO2 value from propagating to the next stages of the process and unnecessarily activating the motor (7), wasting more energy or providing an inadequate oxygen flow. Point deviations can be caused during measurement by the pulse oximetry sensor (1), due to inaccuracy or improper fitting, excessive movement, or other point variations in behavior on the part of a user with the pulse oximetry sensor (1) installed. The time interval in which the average SpO2 is calculated is between t1=5s and t2=60s, this being a time interval capable of causing the average Mspo2 of SpO2 to filter out point measurement noise.

[030] In step “d”, the memory represented by block (Bc6) is cleared repeatedly to prevent data from a sequence of previous measurements from affecting the next measurement. One of these data in memory is the average Mspo2 value, which must be deleted periodically so that old measurement values ​​are not taken into account in the average of new SpO2 values. This data also includes the count of the number of times the SpO2 value was categorized as high or low in step “g”, given that the process is continuous and needs to return to previous steps. Petition 870250004190, dated 17 / 01 / 2025, page 23 / 199 15 / 20 initial counts constantly. If the count is not reset, the probability of the motor being activated more times increases, increasing the device's energy consumption, which can be a problem in situations where the electrical network is not stable, making the device more dependent on the battery (4).

[031] In step “e” the SpO2 value is checked to confirm whether oxygen saturation is adequate after the first calculation of the average Mspo2.

[032] In step “f” the microcontroller memory is cleared again and the process is restarted from step “a” instead of proceeding to oxygen flow correction steps.

[033] In step “g” the SpO2 value is categorized as low or high, for adjusting the O2 flow when opening or closing the valve (8.1). The recurring categorization of the SpO2 value allows the oxygen flow to be delivered in the most appropriate way if the patient changes their condition between hyperoxemia and hypoxemia. Thus, the risk of delivering more oxygen to someone going from hypoxemia to hyperoxemia or delivering less oxygen to someone going from hyperoxemia to hypoxemia is reduced.

[034] In steps “h” and “k” SpO2 is measured again to confirm data up to 20 times with an interval of up to 5 seconds between each measurement. The value of up to 20 times prevents the motor (7) from being activated unnecessarily, since the SpO2 value can stabilize naturally, not being a long enough time for a patient who needs low O2 flow to be without adequate oxygenation. The categorization of step “g” must be redone, because, until a patient's natural stabilization, the SpO2 value can fluctuate. Petition 870250004190, dated 17 / 01 / 2025, page 24 / 199 16 / 20

[035] In steps “i” and “l”, the process is restarted from step “a”, if the value of SpÜ2 has stabilized to an expected value.

[036] In step “j”, if the SpÜ2 value is low for too long, the valve (8.1) is opened to restore oxygen flow. The opening of the valve (8.1) is controlled by proportional control action (P), which is a suitable methodology for the present technology because it has a fast response with little microcontroller processing (2) and requires less energy expenditure from the device.

[037] In step “m”, similarly to step “j”, if the SpÜ2 value is high for too long, the valve (8.1) is closed to restore oxygen flow. The closing of the valve (8.1) is controlled by the proportional control action (P).

[038] The protocol for sending to the Block Broker (Bc2) is Message Queuing Telemetry Transport (MQTT), a protocol that is suitable for devices with limited power resources, low data bandwidth consumption, and that works satisfactorily even with intermittent connections or high latency.

[039] The use of the device and process of the present technology is characterized by being for the measurement and control of oxygen flow in oxygen delivery devices, for oxygen therapy procedures.

[040] The present technology can be better understood through the following example, which is not limiting. EXAMPLE 1 - Construction and proof of concept of the present technology

[041] To construct the device for low-flow oxygen therapy automation, as presented, in a non-limiting way, in figures 1, 3A, 3B, 4 and 5, the following components were obtained: input for sensor of Petition 870250004190, dated 17 / 01 / 2025, page 25 / 199 17 / 20 pulse oximetry (1) type Max30100, microcontroller (2) type ESP32, power supply (3), Li-ion battery (4), display (5), drive (6) type UNL2003, stepper motor (7) type 28BYJ-48, flowmeter (8), oxygen source (9), PLA filament holder (12) made on 3D printer, potentiometer (13), voltage module (14), connection points and cable organization (15), laser-cut MDF base (16), buzzer (17), computer (18), test tube (19) and tubing (20).

[042] To assess SpO2 values ​​that would require intervention, following the flowchart in Figure 2, simulated SpO2 values ​​were tested. For the test, a non-toxic graduated cylinder (19) was filled with 200 mL of water at room temperature and a tube (20) connected to an oxygen source (9) was placed inside. The oxygen source was connected to the flowmeter (8) and the motor (7), which connects to the drive (6). A computer (18) was used to simulate different SpO2 values ​​obtained through the input to a pulse oximetry sensor (1), which could measure in a real case. Oxygen was allowed to pass through the tube (20), which bubbled in the water. After activating the potentiometer (13) to turn on the electromechanical components, the device was able to execute the motor drive command (7) for the appropriate opening and closing of the flowmeter valve (8.1), according to the simulated signals.

[043] For testing purposes, saturation values ​​were considered from Status. “Low” SpO2 Status results are SpO2 values ​​from the potentiometer (13) below 90%; “Good” Status: SpO2 values ​​=>90%; and “High” Status: values ​​>96% up to 100%. The actuation time of the valve (8.1) of the flowmeter (8) was programmed for every 5 seconds after the start of each measurement, changing the flow by 1 Petition 870250004190, dated 17 / 01 / 2025, page 26 / 199 18 / 20 liters per minute with each change. In cases of “low” or “high” SpO2 status, the electromechanical mechanisms from the device were expected to be activated, with the opening or closing commands of the valve (8.1) of the flowmeter (8), allowing the increase or decrease of the oxygen output, respectively.

[044] From this experiment, simulations of hypothetical cases were carried out, with SpO2 values ​​simulated from the potentiometer (13), obtaining the values ​​reported in figures 6, 7 and 8. These graphs (figure 6, figure 7 and figure 8) show the relationship of opening the valve (8.1) of the flowmeter (8) altering the oxygen flow measured in liters per minute in relation to time in seconds and the simulated SpO2. Figure 6 shows situation 1, in which the initial phase (time = 0 to 5 seconds) shows that during the first 5 seconds the valve (8.1) of the flowmeter (8) was fully closed and the simulated SpO2 was 82%, indicating a “low” status. This period shows the baseline condition before the device intervention. From 5 seconds onwards, the device sent commands to activate the motor (7) to open the valve (8.1) of the flowmeter (8) at 1 L / min, simultaneously with the manual alteration of SpO2 from the potentiometer (13) simulating a realistic situation. In this way, the continuous increase in flow culminated in the SpO2 status “Good” (SpO2 = >90%) at 19 seconds, when flowmeter (8) reached 3 L / min and stabilized without the need for further increases in flow.

[045] Figure 7 presents situation 2, in which the initial phase (time = 0 to 5 seconds) shows that during the first 5 seconds the valve (8.1) of the flowmeter (8) was fully closed and the simulated SpO2 was 87%, indicating a “low” value. This period demonstrates the baseline condition before the device intervention. From 5 seconds onwards, the device sent Petition 870250004190, dated 17 / 01 / 2025, page 27 / 199 19 / 20 commands to activate the motor (7) to open the valve (8.1) of the flowmeter (8) at 1 L / min, simultaneously with the manual alteration of SpO2 from the potentiometer (13) simulating a realistic situation. In this way, the continuous increase in flow culminated in the "Good" SpO2 situation (SpO2 = >90%) at 11 seconds, when the flowmeter (8) reached 2 L / min and stabilized without the need for further increases in flow. Figure 8 shows situation 3, in which the initial phase (time = 0 to 5 seconds) demonstrates that during the first 5 seconds the valve (8.1) of the flowmeter (8) was fully closed and the simulated SpO2 was 88%, indicating a "low" value. This period demonstrates the baseline condition before the device intervention. From 5 seconds onwards, the device sent commands to activate the motor (7) to open the valve (8).1) of the flowmeter (8) at 1 L / min, simultaneously with the manual alteration of SpO2 from the potentiometer (13) simulating a realistic situation. In this way, the continuous increase in flow culminated in the “Good” SpO2 situation (SpO2 = >90%) at 16 seconds, when the flowmeter (8) reached 3 L / min, however, as in a realistic situation, a continuous increase in SpO2 was simulated through the potentiometer even without an increase in O2 flow, until at the instant 19 seconds when the SpO2 reached the “High” status (SpO2 >96% up to 100%), having a new activation of the device to the motor (7) to close the valve (8.1) of the flowmeter (8) at 1 L / min, increasing to 2 L / min. After this adjustment, manual changes were made to the potentiometer (13) for a “good” SpO2 status, with the oxygen flow stabilizing at 2 L / min without the need for further flow reductions.The experiments demonstrated that the device provided efficient actuation in correcting the simulated situations, and the response curve in the graph (Figure 6, Figure 7, and Figure 8) shows that... Petition 870250004190, dated 17 / 01 / 2025, page 28 / 199 The 20 / 20 device was able to adapt the flow to the needs of each case in real time, optimizing oxygen consumption.

[046] This test successfully demonstrated that the constructed device, along with the device control process, can be used to increase or decrease the oxygen supply to a patient, automating low-flow oxygen therapy, enabling connectivity between each component of the device, maintaining the device's low dimensions, utilizing flowmeters already used in hospital networks, obtaining precise and rapid results, being easy to construct or install, and having the possibility of continuous use. Petition 870250004190, dated 17 / 01 / 2025, p. 29 / 199

Claims

1 / 4 CLAIMS 1. DEVICE FOR AUTOMATING OXYGEN FLOW CONTROL, comprising an input for a pulse oximetry sensor (1), a microcontroller (2), a power supply (3), a battery (4), a display (5), a drive (6), a motor (7), a flowmeter (8), a voltage module (14), connection points and cable organization (15) and a buzzer (17), characterized by the microcontroller (2), powered by the power supply (3) and the battery (4) through the voltage module (14), sending a signal from the input to a pulse oximetry sensor (1) to a display (5), to a buzzer (17) and to a drive (6), which is connected to a motor (7) that is connected to a flowmeter (8) through a support (12), where the flowmeter (8) is connected to an oxygen source (9) and to the support (12) formed by two hollow cylinders connected in such a way that the larger cylinder (12.1) fits into the valve (8.1) of the flowmeter (8) and the smaller cylinder (12.2) fits into the motor (7), and a potentiometer (13).

2. PROCESS FOR AUTOMATING OXYGEN FLOW CONTROL, using the device defined in claim 1, characterized by comprising the following steps: a) Sending the value of peripheral oxygen saturation (SpO2) obtained at a frequency of up to 30 times per second through the input to a pulse oximetry sensor (1) represented by block (bc1) to a microcontroller (2), which comprises a display (5), which is associated with block (bc4), and a Broker (10) represented by block (bc2) connected to a node-RED (11); b) Restarting the process from step “a”, triggering audible warning signals via the buzzer (17) and visual signals through the display (5), if the SpO2 value is below 30% or if it is above 100%; Petition 870250004190, dated 17 / 01 / 2025, p. 30 / 199 2 / 4 c) Calculate the mean Mspo2 of SpÜ2 over a time interval between t1=5s and t2=60s, as represented by block (Bc5);d) Clear the microcontroller memory variables (2), as shown in block (bc6), restarting the process from step “a”, if the condition 90% < Mspo2 < 96% is met; e) Check if the SpÜ2 value follows the condition 90% < SpÜ2 < 96%, if Mspo2 < 90% or Mspo2 > 96%, as represented by block (Bc7); f) Clear the microcontroller memory variables (2), as shown in block (bc6), restarting the process from step “a”, if the SpÜ2 checked in step “e” meets the condition 90% < SpO2 < 96%; g) Categorize in block (Bc8) the SpÜ2 as low if its value is less than 90% and high if its value is above 96%;h) Send the SpO2 value through the input to a pulse oximetry sensor (1), represented by block (bc9), to a microcontroller (2) up to 20 times, if the SpO2 value was categorized as low in step “g”, respecting a time of up to 5 seconds between each sending of the SpO2 value, repeating the SpO2 categorization of step “g” of block (Bc8) in each sending of SpO2 to the pulse oximetry sensor (1); i) Restart the process from step “a”, if the SpO2 in step “h” satisfies the condition 90% < SpO2 < 96%;j) Activate the motor (7) by sending a signal from the microcontroller (2) to the module (6) and then to the motor (7), which is connected to the flowmeter (8) by means of the support (12), opening the valve (8.1) of the flowmeter (8), if the SpÜ2 value has been categorized as low in step “g” up to 20 times, restarting the process from step “a”, where the valve (8.1) is opened following the proportional control action (P) with the proportional action error calculated by the difference between the expected SpO2 value within the range 90% < SpÜ2 < 96% with the obtained SpO2 value;k) Send the SpO2 value through the input to a pulse oximetry sensor (1), represented by block (bc17), to a microcontroller (2) up to 20 times, if the SpO2 value was categorized as high in step “g”, respecting a time of up to 5 seconds between each sending of the SpO2 value, repeating the SpO2 categorization of step “g” of block (Bc8) in each sending of SpO2 to the pulse oximetry sensor (1); l) Restart the process from step “a”, if the SpO2 in step “k” satisfies the condition 90% < SpÜ2 < 96%;m) Activate the motor (7) by sending a signal from the microcontroller (2) to the module (6) and then to the motor (7), which is connected to the flowmeter (8) by means of the support (12), closing the valve (8.1) of the flowmeter (8), if the SpO2 value has been categorized as high in step “g” up to 20 times, restarting the process from step “a”, where the valve (8.1) is closed following the proportional control action (P) with the error of the proportional action calculated through the difference between the expected gas concentration value and the obtained gas concentration value.

3. PROCESS, according to claim 2, characterized in that, in step b, the transmission protocol to the Block Broker (Bc2) is Message Queuing Telemetry Transport (MQTT).

4. USE of the device defined in claim 1, characterized by being for the measurement and control of flow in oxygen supply devices. Petition 870250004190, dated 17 / 01 / 2025, page 32 / 199 4 / 4 5. USE of the process defined in claim 2, characterized by being for the measurement and control of flow in oxygen supply devices. Petition 870250004190, dated 17 / 01 / 2025, page 33 / 199

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