Blood temperature regulation device, method, and cardiopulmonary bypass system

Abstract

The application relates to a blood temperature regulating device, method and cardiopulmonary bypass system. The device comprises a semiconductor refrigeration device in contact with a blood pipeline to be regulated in temperature. A current sensor is electrically connected with the semiconductor refrigeration device and used for collecting working current. A temperature sensor is arranged on the blood pipeline and used for collecting the actual temperature of the blood pipeline. A temperature control circuit is electrically connected with the semiconductor refrigeration device and used for providing working current for the semiconductor refrigeration device. A control module is used for determining a target voltage according to the actual temperature and a target temperature of the blood pipeline. The actual voltage of the semiconductor refrigeration device is determined according to the working current, and the temperature control circuit is controlled to adjust the amplitude and direction of the working current according to the actual voltage and the target voltage of the semiconductor refrigeration device. In summary, the device of the application regulates the temperature of the blood pipeline twice, ensures that the temperature of the blood pipeline is consistent with the target temperature, and improves the accuracy of temperature regulation of the blood pipeline.

Description

Technical Field

[0001] This application relates to the field of medical device technology, and in particular to a blood temperature regulation device, method, and cardiopulmonary circulation system. Background Technology

[0002] With the development of medical technology, cardiopulmonary bypass systems have emerged, enabling emergency treatment for patients with severe cardiopulmonary failure. These systems use an artificial lung and an artificial heart to provide continuous extracorporeal respiratory and circulatory support, thus sustaining the patient's life. A crucial step in this process is the use of the artificial heart to draw blood from the patient's body through tubing, exchange oxygen and carbon dioxide outside the body, and then return the blood to the patient through the same tubing. During this extracorporeal circulation, the blood temperature must be maintained at the necessary level to ensure the effectiveness of the treatment.

[0003] In traditional techniques, heating equipment is used to heat the blood, thereby raising its temperature.

[0004] However, traditional technologies are not precise enough in regulating blood temperature, especially in the cardiopulmonary circulation system, where precise temperature control is crucial as it directly affects the patient's life. Summary of the Invention

[0005] Therefore, it is necessary to provide a blood temperature regulation device, method, and cardiopulmonary circulation system that can accurately regulate blood temperature in response to the above-mentioned technical problems.

[0006] A blood temperature regulating device includes: a semiconductor cooling device for exchanging temperature with a blood tubing to be regulated; when a working current is provided to the semiconductor cooling device, the semiconductor cooling device absorbs heat or cools the blood tubing to regulate the actual temperature of the blood tubing; a current sensor electrically connected to the semiconductor cooling device for collecting the working current; a temperature sensor disposed on the blood tubing for collecting the actual temperature of the blood tubing; a temperature control circuit electrically connected to the semiconductor cooling device for providing the working current to the semiconductor cooling device; and a control module electrically connected to the current sensor, the temperature sensor, and the temperature control circuit, respectively, for determining a target voltage based on the actual temperature and target temperature of the blood tubing; determining the actual voltage of the semiconductor cooling device based on the working current; and controlling the temperature control circuit to adjust the amplitude and direction of the working current based on the actual voltage of the semiconductor cooling device and the target voltage.

[0007] In one embodiment, the temperature control circuit includes: a current generating circuit, the control terminal of which is electrically connected to the control module, for generating the operating current; and a current commutation circuit, the input terminal of which is electrically connected to the output terminal of the current generating circuit, the control terminal of which is electrically connected to the control module, and the output terminal of which is electrically connected to the semiconductor refrigeration device; the control module is used to determine the actual voltage of the semiconductor refrigeration device based on the operating current, and to control the amplitude of the operating current generated by the current generating circuit and the direction of the operating current adjusted by the current commutation circuit based on the actual voltage of the semiconductor refrigeration device and the target voltage.

[0008] In one embodiment, the blood temperature regulating device further includes a power module electrically connected to the current generating circuit for supplying power to the current generating circuit.

[0009] In one embodiment, the current generating circuit includes: a switch, a pulse signal generator, and an inductor; a first terminal of the switch is connected to the positive terminal of the power supply module, a second terminal of the switch is connected to the first terminal of the inductor, a control terminal of the switch is connected to the output terminal of the pulse signal generator, an input terminal of the pulse signal generator is connected to the control module, a second terminal of the inductor is connected to the first terminal of the current commutation circuit, and a second terminal of the current commutation circuit is connected to the negative terminal of the power supply module; the control module is used to control the pulse signal generator to adjust the duty cycle of the switch to adjust the amplitude of the operating current.

[0010] In one embodiment, the current generating circuit further includes: a first capacitor connected in parallel with the power supply module; a freewheeling diode, the anode of which is connected to the cathode of the power supply module, and the cathode of which is connected to the second terminal of the switch; and a second capacitor, the first terminal of which is connected to the cathode of the power supply module, and the second terminal of which is connected to the second terminal of the inductor.

[0011] In one embodiment, the current generating circuit further includes: a first resistor, a first end of which is connected to a second end of the inductor; a second resistor, a first end of which is connected to a second end of the first resistor, and a second end of which is connected to the negative terminal of the power supply module; a comparator, a first input terminal of which is connected to a first end of the second resistor, a second input terminal of which is used to receive a reference voltage signal, and an output terminal of which is connected to the input terminal of the pulse signal generator; and a third resistor, a first end of which is connected to a first end of the second resistor, and a second end of which is connected to the control module.

[0012] In one embodiment, the current commutation circuit includes: a first switching transistor, the collector of which is connected to a second terminal of the inductor, and the base of which is connected to the control module; a second switching transistor, the collector of which is connected to the emitter of the first switching transistor, and the base of which is connected to the control module, and the emitter of which is connected to the negative terminal of the power supply module; a third switching transistor, the collector of which is connected to a second terminal of the inductor, and the base of which is connected to the control module; a fourth switching transistor, the collector of which is connected to the emitter of the third switching transistor, and the base of which is connected to the control module, and the emitter of which is connected to the negative terminal of the power supply module; one end of a semiconductor cooling device is connected to the emitter of the first switching transistor, and the other end of the semiconductor cooling device is connected to the emitter of the third switching transistor; the control module is used to control the conduction states of the first switching transistor, the second switching transistor, the third switching transistor, and the fourth switching transistor respectively, so as to adjust the direction of the operating current.

[0013] In one embodiment, the blood temperature regulating device further includes: a human-machine interaction module connected to the control module, used to display parameters of the target temperature, the actual temperature, and the operating current, and to receive a user command signal including the target temperature and send the user command signal to the control module.

[0014] In one embodiment, the control module is also configured to issue an alarm signal when the actual temperature exceeds a preset range.

[0015] A method for regulating blood temperature, comprising:

[0016] The actual temperature and target temperature of the blood tubing to be temperature-controlled are obtained, wherein the blood tubing is in contact with a semiconductor cooling device; when a working current is provided to the semiconductor cooling device, the semiconductor cooling device absorbs heat or cools the blood tubing to regulate the actual temperature of the blood tubing.

[0017] The target voltage is determined based on the actual temperature and target temperature of the blood tubing.

[0018] The actual voltage of the semiconductor cooling device is determined based on the operating current, and the amplitude and direction of the operating current are controlled based on the actual voltage of the semiconductor cooling device and the target voltage.

[0019] A cardiopulmonary circulation system, the system comprising the above-mentioned blood temperature regulating device, and / or employing the above-mentioned blood temperature regulating method to assist extracorporeal blood circulation.

[0020] The aforementioned blood temperature regulation device, method, and cardiopulmonary bypass system. By incorporating a semiconductor cooling device in contact with the blood tubing to be regulated, the semiconductor cooling device absorbs or cools the blood tubing by providing an operating current, thereby regulating the actual temperature of the blood tubing. A current sensor is used to collect the operating current of the semiconductor cooling device. A temperature sensor is used to collect the actual temperature of the blood tubing. A temperature control circuit is used to provide an operating current to the semiconductor cooling device. A control module is used to determine a target voltage based on the actual and target temperatures of the blood tubing. By outputting an operating current to the semiconductor cooling device based on the target voltage, the temperature of the semiconductor cooling device is regulated, thereby ensuring that the actual and target temperatures of the blood tubing are consistent, achieving the first stage of temperature regulation of the blood tubing. Then, the actual voltage of the semiconductor cooling device is determined based on the operating current. This actual voltage is then compared with the target voltage. If they are inconsistent, it means the current temperature of the semiconductor cooling device is insufficient to match the actual temperature of the blood tubing with the target temperature. Therefore, based on the actual and target voltages of the semiconductor cooling device, the temperature control circuit adjusts the amplitude and direction of the output operating current, thereby regulating the operating current of the semiconductor cooling device and consequently its temperature. This ensures that the actual temperature of the blood tubing in contact with the semiconductor cooling device matches the target temperature, achieving a second temperature regulation of the blood tubing. In summary, the device of this application regulates the temperature of the blood tubing in two stages. The first regulation adjusts the actual temperature of the blood tubing based on the target temperature, theoretically enabling the blood tubing to reach the target temperature. However, in practice, circuit errors prevent the blood tubing from reaching the target temperature after the first regulation. Therefore, the second regulation, based on the sampled operating current, overcomes the circuit error, ensuring the blood tubing temperature matches the target temperature and improving the accuracy of temperature control of the blood tubing. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this application or the conventional technology, the drawings used in the description of the embodiments or the conventional technology will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the blood temperature regulating device in one embodiment;

[0023] Figure 2This is a schematic diagram of the blood temperature regulating device in another embodiment;

[0024] Figure 3 This is a circuit diagram of a temperature control circuit in one embodiment;

[0025] Figure 4 This is a schematic diagram of the blood temperature regulating device in yet another embodiment;

[0026] Figure 5 This is a flowchart of a blood temperature regulation method in one embodiment.

[0027] Explanation of reference numerals in the attached figures: 10-Semiconductor cooling device, 20-Blood tubing, 30-Current sensor, 40-Temperature sensor, 50-Temperature control circuit, 60-Control module, 51-Current generating circuit, 52-Current commutation circuit, 70-Power supply module, 53-Pulse signal generator, 54-Comparator, 80-Human-machine interaction module. Detailed Implementation

[0028] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings, which illustrate embodiments of the present application. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of this application will be thorough and complete.

[0029] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0030] It is understood that the terms “first,” “second,” etc., used in this application may be used herein to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish one element from another.

[0031] It should be noted that when one element is considered to be "connected" to another element, it can be directly connected to the other element or connected to the other element through an intermediary element. Furthermore, in the following embodiments, "connection" should be understood as "electrical connection," "communication connection," etc., if there is transmission of electrical signals or data between the connected objects.

[0032] When used herein, the singular forms of “a,” “an,” and “the” may also include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising,” “including,” or “having,” etc., specify the presence of the stated feature, whole, step, operation, component, part, or combination thereof, but do not preclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof.

[0033] In one embodiment, such as Figure 1 As shown, a blood temperature regulating device is provided, including: a semiconductor cooling device 10, a current sensor 30, a temperature sensor 40, a temperature control circuit 50, and a control module 60. Wherein:

[0034] The semiconductor cooling device 10 is in direct or indirect contact with the blood tubing 20 to be conditioned, so as to achieve temperature exchange.

[0035] Specifically, when a working current is supplied to the semiconductor cooling device 10, the semiconductor cooling device 10 absorbs heat or cools the blood conduit 20 to regulate the actual temperature of the blood conduit 20.

[0036] Specifically, based on the Peltier principle, when two different semiconductors form a circuit and direct current is applied, heat will be released at one junction in addition to Joule heating, while heat will be absorbed at the other junction. This phenomenon caused by the Peltier effect is reversible. When the direction of the current is changed, the junctions that release and absorb heat also change. The heat absorbed and released is proportional to the intensity of the direct current.

[0037] For example, the semiconductor cooling device 10 is fixed to the blood line 20 by a tube clamp, and the semiconductor cooling device 10 exchanges heat with the wall of the blood line 20.

[0038] For example, the semiconductor cooling device 10 is an electrical couple composed of N-type and P-type semiconductors. The electrical couple is equivalent to a capacitor, having positive and negative plates with air or an insulating material filling the space between them. For the electrical couple formed by connecting P-type and N-type semiconductor materials, applying a DC power supply to both ends causes energy transfer. That is, the junction where the current flows from the N-type material to the P-type material becomes the cold end, where electron-hole pairs are generated, internal energy decreases, and this manifests as cooling and heat absorption. Conversely, the junction where the current flows from the P-type material to the N-type material becomes the hot end, internal energy increases, and this manifests as heating and heat dissipation.

[0039] The current sensor 30 is electrically connected to the semiconductor refrigeration device 10 and is used to collect the operating current supplied to the semiconductor refrigeration device.

[0040] For example, since the temperature control accuracy requirements of the semiconductor cooling device 10 are high, especially in cardiopulmonary bypass systems, the inventors of this application have found that the sampling rate of the current sensor 30 for sampling the operating current needs to be higher than 1 kHz.

[0041] Temperature sensor 40 is installed on blood tubing 20 to collect the actual temperature of blood tubing 20.

[0042] For example, since the temperature of the blood tubing 20 does not change abruptly, the sampling frequency of the temperature sensor 40 only needs to be greater than 100Hz.

[0043] Temperature control circuit 50 is electrically connected to semiconductor refrigeration device 10 and is used to provide operating current to semiconductor refrigeration device 10.

[0044] Specifically, the magnitude and direction of the operating current provided by the temperature control circuit 50 are adjustable.

[0045] The control module 60 is electrically connected to the current sensor 30, the temperature sensor 40, and the temperature control circuit 50, respectively, and is used to determine the target voltage based on the actual temperature and target temperature of the blood tubing 20. It determines the actual voltage of the semiconductor cooling device 10 based on the operating current, and controls the temperature control circuit 50 to adjust the amplitude and direction of the operating current based on the actual voltage of the semiconductor cooling device 10 and the target voltage.

[0046] Specifically, the control module 60 determines the temperature difference between the actual temperature of the blood tubing 20 fed back by the temperature sensor and the preset target temperature. Then, based on the correspondence between the temperature difference and the preset temperature of the thermoelectric cooler 10, it determines how much the temperature of the thermoelectric cooler 10 needs to be adjusted. Furthermore, based on the correspondence between the preset target voltage and the temperature of the thermoelectric cooler 10, it determines the target voltage. Theoretically, after the thermoelectric cooler 10 receives the current generated according to the target voltage, it can make the actual temperature of the blood tubing 20 consistent with the target temperature. However, due to unavoidable parameter errors in the circuit, a single-loop adjustment method is insufficient to accurately reach the expected target temperature for the actual temperature of the blood tubing 20. Further, in this application, the operating current of the thermoelectric cooler 10 is collected, the actual voltage is determined based on the operating current, and then the temperature control circuit 50 is controlled to adjust the amplitude and direction of the operating current based on the actual voltage of the thermoelectric cooler 10 and the target voltage. This overcomes the influence of errors in the circuit and employs a dual-loop adjustment method to reliably adjust the actual temperature of the blood tubing 20 to the target temperature.

[0047] For example, the control module 60 may include a PID (proportion-integral-differential) controller. On one hand, the PID controller can determine the deviation value and deviation rate based on the difference between the target temperature and the actual temperature, and then use a PID algorithm to determine the target voltage based on the deviation value and deviation rate. On the other hand, the PID controller can also set the proportional coefficient, integral coefficient, derivative coefficient, and corresponding adjustment amount in the PID controller according to the magnitude of the difference between the target voltage and the actual voltage, the rate of change, and the voltage limit requirements. Then, the temperature control circuit 50 is controlled by the PID controller to adjust the amplitude and direction of the operating current.

[0048] In this embodiment, by providing a semiconductor cooling device 10 in contact with the blood tubing 20 to be temperature-regulated, the semiconductor cooling device 10 can absorb heat or cool the blood tubing 20 by providing operating current to the semiconductor cooling device 10, thereby regulating the actual temperature of the blood tubing 20. A current sensor 30 is provided to collect the operating current of the semiconductor cooling device 10. A temperature sensor 40 is provided to collect the actual temperature of the blood tubing 20. A temperature control circuit 50 is provided to provide operating current to the semiconductor cooling device 10. A control module 60 is provided to determine a target voltage based on the actual temperature and target temperature of the blood tubing 20. By outputting operating current to the semiconductor cooling device 10 according to the target voltage, the temperature of the semiconductor cooling device 10 can be adjusted, thereby making the actual temperature of the blood tubing 20 consistent with the target temperature, achieving the first temperature regulation of the blood tubing 20. Then, the actual voltage of the semiconductor cooling device 10 is determined based on the operating current. The actual voltage of the semiconductor cooling device 10 is then compared with the target voltage. If they are inconsistent, it means that the current temperature of the semiconductor cooling device 10 cannot make the actual temperature of the blood tubing 20 consistent with the target temperature. Therefore, the temperature control circuit 50 is controlled to adjust the amplitude and direction of the output operating current based on the actual voltage and target voltage of the semiconductor cooling device 10, thereby adjusting the operating current of the semiconductor cooling device 10 and thus adjusting the temperature of the semiconductor cooling device 10. This makes the actual temperature of the blood tubing 20 in contact with the semiconductor cooling device 10 consistent with the target temperature, thus achieving the second adjustment of the temperature of the blood tubing 20. In summary, the device of this application adjusts the temperature of the blood tubing 20 twice (i.e., the aforementioned dual-loop adjustment). The first adjustment adjusts the actual temperature of the blood tubing according to the target temperature, so that the temperature of the blood tubing 20 can theoretically reach the target temperature. However, in practice, due to circuit errors, the blood tubing 20 cannot reach the target temperature after the first adjustment. Therefore, the second adjustment is made according to the sampling working current to overcome the circuit error, ensure that the temperature of the blood tubing 20 is consistent with the target temperature, and improve the accuracy of temperature control of the blood tubing 20.

[0049] In one embodiment, such as Figure 2 As shown, the temperature control circuit 50 includes: a current generating circuit 51 and a current commutation circuit 52, wherein:

[0050] The control terminal of the current generating circuit 51 is electrically connected to the control module 60. The current generating circuit 51 is used to generate the working current.

[0051] For example, the current generating circuit 51 can be a DC-DC converter circuit that is connected to an external power supply and can convert the received voltage value into the required voltage value to generate an operating current output.

[0052] The input terminal of the current commutation circuit 52 is electrically connected to the output terminal of the current generating circuit 51, the control terminal of the current commutation circuit 52 is electrically connected to the control module 60, and the output terminal of the current commutation circuit 52 is electrically connected to the semiconductor cooling device 10.

[0053] Specifically, the current commutation circuit 52 is electrically connected to both ends of the semiconductor cooling device 10, and the current commutation circuit 52 can adjust the direction of the current on the semiconductor cooling device 10.

[0054] The control module 60 is used to determine the actual voltage of the semiconductor cooling device 10 based on the operating current, and to control the amplitude of the operating current generated by the current generating circuit 51 and the direction of the operating current adjusted by the current commutation circuit 52 based on the actual voltage of the semiconductor cooling device 10 and the target voltage.

[0055] Specifically, the control module 60 adjusts the amplitude and direction of the operating current according to the actual voltage and the target voltage, so that the voltage on the semiconductor cooling device 10 can reach the target voltage.

[0056] In this embodiment, by setting a current generating circuit 51, a working current can be generated and its amplitude adjusted. By setting a current commutation circuit 52, the direction of the working current flowing through the semiconductor cooling device 10 can be adjusted, so that the voltage on the semiconductor cooling device 10 can reach the target voltage, thereby cooling or heating the blood tubing 20, and adjusting the actual temperature of the blood tubing 20 to the target temperature.

[0057] In one embodiment, please see [link to previous article]. Figure 2 The blood temperature regulating device also includes a power supply module 70. The power supply module 70 is electrically connected to the current generating circuit 51 and is used to supply power to the current generating circuit 51.

[0058] In this embodiment, a power supply module 70 is provided to supply power to the current generating circuit 51, thereby facilitating the generation of operating current by the current generating circuit 51.

[0059] In one embodiment, such as Figure 3 As shown, the current generating circuit 51 includes: a switch S1, a pulse signal generator 53, and an inductor L1. Wherein:

[0060] The first terminal of switch S1 is connected to the positive terminal of power module 70, the second terminal of switch S1 is connected to the first terminal of inductor L1, the control terminal of switch S1 is connected to the output terminal of pulse signal generator 53, the input terminal of pulse signal generator 53 is connected to control module 60, and the second terminal of inductor L1 is connected to the first terminal of current commutation circuit 52. The second terminal of current commutation circuit 52 is connected to the negative terminal of power module 70.

[0061] Specifically, by placing an inductor L1 between the current generating circuit 51 and the current commutation circuit 52, the operating current generated by the current generating circuit 51 must first flow through the inductor L1 before flowing into the current commutation circuit 52. Due to the energy storage characteristic of the inductor L1, the current in the circuit will not change abruptly, thus the current received by the semiconductor cooling device 10 will not change abruptly, and the semiconductor cooling device 10 will not receive a reverse current instantaneously.

[0062] Specifically, by setting inductor L1, a buffering effect can be achieved, avoiding the phenomenon of heat generation of components in the circuit caused by instantaneous high-order harmonics generated during the rapid opening and closing of switch S1, thereby improving the lifespan of each component in the circuit.

[0063] For example, switch S1 is a switching transistor.

[0064] The control module 60 is used to control the duty cycle of the pulse signal generator 53 adjustment switch S1 to adjust the amplitude of the working current.

[0065] Specifically, the control module 60 can control the pulse signal generator 53 to output a corresponding pulse signal based on the difference between the actual voltage and the target voltage. The switch S1 opens and closes according to the received pulse signal, thereby adjusting its duty cycle and regulating the output voltage.

[0066] For example, the formula for the voltage output by the current generating circuit 51 is as follows:

[0067] V out =D*V in

[0068] Among them, V out V is the voltage output of the current generating circuit 51, D is the duty cycle of switch S1, and V is the voltage value. in The voltage value input to the current generating circuit 51.

[0069] In this embodiment, by setting a switch S1 and a pulse signal generator 53, the control module 60 controls the duty cycle of the switch S1 through the pulse signal generator 53, thereby achieving control of the operating current amplitude. By setting an inductor L1, a buffering effect is achieved, preventing sudden changes in the current in the circuit, thus protecting the devices in the circuit, especially the semiconductor cooling device 10.

[0070] In one embodiment, please continue to participate Figure 3 The current generating circuit 51 also includes: a first capacitor C1, a freewheeling diode D1, and a second capacitor C2, wherein:

[0071] The first capacitor C1 is connected in parallel with the power module 70.

[0072] Specifically, by setting the first capacitor C1, the electrical signal output by the power supply module 70 is filtered to reduce the interference of the electrical signal received by the current generating circuit 51.

[0073] The anode of the freewheeling diode D1 is connected to the negative terminal of the power module 70, and the cathode of the freewheeling diode D1 is connected to the second terminal of the switch.

[0074] Specifically, when switch S1 is on, the cathode voltage of freewheeling diode D1 is higher than the anode voltage, and freewheeling diode D1 is reverse-biased and cut off. At this time, the operating current is output to the load through inductor L1, and energy is stored in inductor L1. When switch S1 is off, the energy stored in inductor L1 cannot be released immediately. The induced current generated forms a freewheeling path through the load and freewheeling diode D1, continuing to supply power to the load.

[0075] The first terminal of the second capacitor C2 is connected to the negative terminal of the power module 70, and the second terminal of the second capacitor C2 is connected to the second terminal of the inductor L1.

[0076] Specifically, by setting the first capacitor C1, the electrical signal output by the current generating circuit 51 is filtered to reduce interference in the electrical signal output by the current generating circuit 51.

[0077] In this embodiment, by setting the first capacitor C1 and the second capacitor C2, interference in the circuit is reduced. By setting the freewheeling diode D1, the continuous output of the operating current is ensured, and sudden changes in the current in the circuit are avoided, making the current in the circuit smoother, thereby protecting the semiconductor cooling device 10.

[0078] In one embodiment, the current generating circuit 51 further includes: a first resistor R1, a second resistor R2, a comparator 54, and a third resistor R3, wherein:

[0079] The first terminal of the first resistor R1 is connected to the second terminal of the inductor L1.

[0080] The first end of the second resistor R2 is connected to the second end of the first resistor R1, and the second end of the second resistor R2 is connected to the negative terminal of the power module 70.

[0081] Specifically, the first resistor R1 and the second resistor R2 are voltage divider resistors, which facilitates the determination of the overall voltage across the first resistor R1 and the second resistor R2 by using the voltage across the second resistor R2 and the resistance values ​​of the first resistor R1 and the second resistor R2.

[0082] The first input terminal of comparator 54 is connected to the first terminal of the second resistor R2, the second input terminal of comparator 54 is used to receive the reference voltage signal, and the output terminal of comparator 54 is connected to the input terminal of pulse signal generator 53.

[0083] Specifically, comparator 54 compares the voltage across the second resistor R2 with a reference voltage signal, and then outputs high or low level signals to control pulse signal generator 53 to adjust the duty cycle of the output pulse signal until the voltage across the second resistor R2 stabilizes at the reference voltage signal. For example, when the voltage across the second resistor R2 is greater than the reference voltage signal, comparator 54 controls pulse signal generator 53 to decrease the duty cycle of the output pulse signal, causing the voltage in the circuit to decrease until the voltage across the second resistor R2 equals the reference voltage signal. When the voltage across the second resistor R2 is less than the reference voltage signal, comparator 54 controls pulse signal generator 53 to increase the duty cycle of the output pulse signal, causing the voltage in the circuit to increase until the voltage across the second resistor R2 equals the reference voltage signal.

[0084] The first end of the third resistor R3 is connected to the first end of the second resistor R2, and the second end of the third resistor R3 is connected to the control module 60.

[0085] Specifically, the third resistor R3 can be a current-limiting resistor.

[0086] For example, the voltage output by the current generating circuit 51 can be expressed by the following formula:

[0087]

[0088] Among them, V out V represents the voltage output by the current generating circuit 51. R1 is the resistance of the first resistor R1, R2 is the resistance of the second resistor R2, and R3 is the resistance of the third resistor R3. R2 V is the voltage across the second resistor R2 when the circuit is balanced. R2 =V ref V ref As a reference voltage signal, U adj This is the analog control signal output by the control module 60. Therefore, the voltage output by the current generating circuit 51 is only related to the control signal output by the control module 60, thus enabling the control module 60 to control the operating current output by the current generating circuit 51. Simultaneously, the current generating circuit 51 can also dynamically balance the output operating current; for example, when the voltage across the second resistor R2 is less than V... ref At that time, under the action of comparator 54, pulse signal generator 53 will increase the duty cycle of the output pulse signal, thereby increasing V. R2 until V R2 =V ref Similarly, when the voltage across the second resistor R2 is greater than V... ref At that time, under the action of comparator 54, pulse signal generator 53 will reduce the duty cycle of the output pulse signal, thereby reducing V. R2 until VR2 =V ref This stabilizes the voltage signal output by the current generating circuit 51.

[0089] In this embodiment, by setting a first resistor R1, a second resistor R2, a comparator 54, and a third resistor R3, a feedback regulation mechanism is established in the circuit, which can dynamically balance the voltage signal output by the current generating circuit 51 and enable the control module 60 to control the voltage output by the current generating circuit 51.

[0090] In one embodiment, please see [link to previous article]. Figure 3 The current commutation circuit 52 includes: a first switch Q1, a second switch Q2, a third switch Q3, and a fourth switch Q4, wherein:

[0091] The collector of the first switching transistor Q1 is connected to the second terminal of the inductor L1, and the base of the first switching transistor Q1 is connected to the control module 60.

[0092] The collector of the second switch Q2 is connected to the emitter of the first switch Q1, the base of the second switch Q2 is connected to the control module 60, and the emitter of the second switch Q2 is connected to the negative terminal of the power supply module 70.

[0093] The collector of the third switch Q3 is connected to the second terminal of the inductor L1, and the base of the third switch Q3 is connected to the control module 60.

[0094] The collector of the fourth switch Q4 is connected to the emitter of the third switch Q3, the base of the fourth switch Q4 is connected to the control module 60, and the emitter of the fourth switch Q4 is connected to the negative terminal of the power supply module 70.

[0095] One end of the semiconductor cooling device 10 is connected to the emitter of the first switching transistor Q1, and the other end of the semiconductor cooling device 10 is connected to the emitter of the third switching transistor Q3.

[0096] The control module 60 is used to control the conduction states of the first switch Q1, the second switch Q2, the third switch Q3, and the fourth switch Q4 respectively, so as to adjust the direction of the working current.

[0097] Specifically, when the first switch Q1 and the fourth switch Q4 are turned on, and the second switch Q2 and the third switch Q3 are turned off, current flows from the first side to the second side of the semiconductor cooling device 10. When the second switch Q2 and the third switch Q3 are turned on, and the first switch Q1 and the fourth switch Q4 are turned off, current flows from the second side to the first side of the semiconductor cooling device 10. This current reversal enables the heating and cooling functions of the semiconductor cooling device 10.

[0098] In this embodiment, the direction of the current flowing through the semiconductor cooling device 10 is controlled by setting the first switch Q1, the second switch Q2, the third switch Q3, and the fourth switch Q4, and then controlling the conduction state of the first switch Q1, the second switch Q2, the third switch Q3, and the fourth switch Q4.

[0099] In one embodiment, such as Figure 4 As shown, the blood temperature regulation device also includes a human-machine interface module 80. The human-machine interface module 80 is connected to the control module 60 and is used to display parameters such as target temperature, actual temperature, and operating current, as well as to receive user command signals including the target temperature and send the user command signals to the control module 60.

[0100] For example, users can view the historical temperature change curve of the blood tubing 20 through the human-computer interaction module 80, and can also set parameters such as target temperature and running time of the blood temperature regulating device.

[0101] In this embodiment, a human-machine interface module 80 is provided to facilitate the display of parameters such as target temperature, actual temperature, and operating current through the human-machine interface, allowing users to intuitively view various key parameters of the blood temperature regulating device during operation. It also facilitates users in setting various operating parameters of the temperature regulating device.

[0102] In one embodiment, the control module is also used to issue an alarm signal when the actual temperature exceeds a preset range.

[0103] Specifically, when the actual temperature exceeds the preset range, it indicates an abnormal temperature in the blood tubing, and an alarm should be issued. The preset range can be set by the user.

[0104] In this embodiment, by setting the control module to issue an alarm signal when the actual temperature exceeds the preset range, the user can be promptly alerted to abnormal blood tubing temperature, allowing the user to take timely measures.

[0105] In one embodiment, such as Figure 5 As shown, a method for regulating blood temperature is provided, including:

[0106] Step S500: Obtain the actual temperature and target temperature of the blood tubing to be heated.

[0107] The blood tubing is in contact with a thermoelectric cooling device. When an operating current is supplied to the thermoelectric cooling device, it absorbs heat or cools the blood tubing to regulate its actual temperature.

[0108] Step S510: Determine the target voltage based on the actual temperature and target temperature of the blood tubing.

[0109] Step S520: Determine the actual voltage of the semiconductor cooling device based on the operating current, and control the amplitude and direction of the operating current based on the actual voltage of the semiconductor cooling device and the target voltage.

[0110] In this embodiment, a semiconductor cooling device is placed in contact with the blood tubing to be regulated. By providing a working current to the semiconductor cooling device, it absorbs or cools the blood tubing, thereby adjusting its actual temperature. A target voltage is determined based on the actual and target temperatures of the blood tubing. Outputting a working current to the semiconductor cooling device based on this target voltage adjusts its temperature, thus matching the actual and target temperatures of the blood tubing, achieving the first temperature regulation. Next, the actual voltage of the semiconductor cooling device is determined based on the working current. This actual voltage is then compared to the target voltage. If they are inconsistent, it indicates that the current temperature of the semiconductor cooling device is insufficient to match the target temperature of the blood tubing. Therefore, the temperature control circuit adjusts the amplitude and direction of the output working current based on the actual and target voltages of the semiconductor cooling device, thereby regulating the working current of the semiconductor cooling device and adjusting its temperature. This again matches the actual and target temperatures of the blood tubing in contact with the semiconductor cooling device, achieving the second temperature regulation. In summary, the device of this application regulates the temperature of the blood tubing in two stages. The first stage adjusts the actual temperature of the blood tubing based on the target temperature, so that the temperature of the blood tubing can theoretically reach the target temperature. However, in practice, due to circuit errors, the blood tubing may not reach the target temperature after the first stage. Therefore, the second stage adjusts the temperature based on the sampling working current to overcome the circuit error, ensure that the temperature of the blood tubing is consistent with the target temperature, and improve the accuracy of temperature control of the blood tubing.

[0111] It should be understood that, although Figure 5 The steps in the flowchart are shown sequentially as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order in which these steps are executed, and they can be performed in other orders. Figure 5 At least some of the steps in the process may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but may be executed at different times. The execution order of these steps or stages is not necessarily sequential, but may be executed in turn or alternately with other steps or at least some of the steps or stages in other steps.

[0112] A cardiopulmonary circulation system, comprising a blood temperature regulating device as described in any of the above embodiments, and / or employing a blood temperature regulating method as described in the above embodiments to assist extracorporeal blood circulation.

[0113] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the methods described above. Any references to memory, storage, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, or optical storage, etc. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM), etc.

[0114] In the description of this specification, references to terms such as "some embodiments," "other embodiments," and "ideal embodiments" indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative descriptions of the above terms do not necessarily refer to the same embodiments or examples.

[0115] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0116] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A blood temperature regulating device, characterized by, include: A semiconductor cooling device, wherein the semiconductor cooling device is in contact with a blood conduit; Used to exchange temperature with the blood tubing to be heated; When the semiconductor cooling device is supplied with operating current, the semiconductor cooling device absorbs heat or cools the blood tubing to regulate the actual temperature of the blood tubing. A current sensor, electrically connected to the semiconductor refrigeration device, is used to collect the operating current; A temperature sensor is installed on the blood tubing to collect the actual temperature of the blood tubing. A temperature control circuit, electrically connected to the semiconductor refrigeration device, is used to provide the operating current to the semiconductor refrigeration device; The control module is electrically connected to the current sensor, the temperature sensor, and the temperature control circuit, respectively, and is used to determine the target voltage based on the actual temperature and the target temperature of the blood tubing. The operating current is output to the semiconductor refrigeration device according to the target voltage; the actual voltage of the semiconductor refrigeration device is determined according to the operating current, and the temperature control circuit is controlled to adjust the amplitude and direction of the operating current according to the actual voltage of the semiconductor refrigeration device and the target voltage.

2. The apparatus according to claim 1, characterized in that, The temperature control circuit includes: A current generating circuit, wherein the control terminal of the current generating circuit is electrically connected to the control module, and is used to generate the working current; A current commutation circuit, wherein the input terminal of the current commutation circuit is electrically connected to the output terminal of the current generating circuit, the control terminal of the current commutation circuit is electrically connected to the control module, and the output terminal of the current commutation circuit is electrically connected to the semiconductor refrigeration device. The control module is used to determine the actual voltage of the semiconductor cooling device based on the operating current, and to control the amplitude of the operating current generated by the current generating circuit and the direction of the operating current adjusted by the current commutation circuit based on the actual voltage of the semiconductor cooling device and the target voltage.

3. The apparatus of claim 2, wherein, The blood temperature regulating device further includes a power module, which is electrically connected to the current generating circuit and is used to supply power to the current generating circuit.

4. The apparatus of claim 3, wherein, The current generating circuit includes: a switch, a pulse signal generator, and an inductor; The first terminal of the switch is connected to the positive terminal of the power supply module, the second terminal of the switch is connected to the first terminal of the inductor, the control terminal of the switch is connected to the output terminal of the pulse signal generator, the input terminal of the pulse signal generator is connected to the control module, the second terminal of the inductor is connected to the first terminal of the current commutation circuit, and the second terminal of the current commutation circuit is connected to the negative terminal of the power supply module. The control module is used to control the pulse signal generator to adjust the duty cycle of the switch, thereby adjusting the amplitude of the operating current.

5. The apparatus of claim 4, wherein, The current generating circuit also includes: The first capacitor is connected in parallel with the power module; A freewheeling diode, wherein the anode of the freewheeling diode is connected to the negative terminal of the power module, and the cathode of the freewheeling diode is connected to the second terminal of the switch; The second capacitor has its first terminal connected to the negative terminal of the power module and its second terminal connected to the second terminal of the inductor.

6. The apparatus of claim 4, wherein, The current generating circuit further includes: A first resistor, wherein a first end of the first resistor is connected to a second end of the inductor; The second resistor has its first end connected to the second end of the first resistor, and its second end connected to the negative terminal of the power module. A comparator, wherein the first input terminal of the comparator is connected to the first terminal of the second resistor, the second input terminal of the comparator is used to receive a reference voltage signal, and the output terminal of the comparator is connected to the input terminal of the pulse signal generator; The third resistor has its first end connected to the first end of the second resistor, and its second end connected to the control module.

7. The apparatus of claim 4, wherein, The current commutation circuit includes: The first switching transistor has its collector connected to the second terminal of the inductor and its base connected to the control module. The second switching transistor has its collector connected to the emitter of the first switching transistor, its base connected to the control module, and its emitter connected to the negative terminal of the power module. The collector of the third switch is connected to the second terminal of the inductor, and the base of the third switch is connected to the control module. The fourth switching transistor has its collector connected to the emitter of the third switching transistor, its base connected to the control module, and its emitter connected to the negative terminal of the power module. One end of the semiconductor cooling device is connected to the emitter of the first switching transistor, and the other end of the semiconductor cooling device is connected to the emitter of the third switching transistor. The control module is used to control the conduction states of the first switch, the second switch, the third switch, and the fourth switch respectively, so as to adjust the direction of the working current.

8. The apparatus according to any one of claims 1-7, characterized in that, The blood temperature regulating device also includes: The human-computer interaction module, connected to the control module, is used to display parameters such as the target temperature, the actual temperature, and the operating current, as well as to receive user command signals including the target temperature and send the user command signals to the control module.

9. The device of any one of claims 1-7, wherein, The control module is also used to issue an alarm signal when the actual temperature exceeds the preset range.

10. A non-transitory computer readable storage medium, comprising: include: A memory, which stores a computer program, executes the following steps when the computer program in the memory is run: The actual temperature and target temperature of the blood tubing to be temperature-controlled are obtained, wherein the blood tubing is in contact with a semiconductor cooling device; when a working current is provided to the semiconductor cooling device, the semiconductor cooling device absorbs heat or cools the blood tubing to regulate the actual temperature of the blood tubing. The target voltage is determined based on the actual temperature and target temperature of the blood tubing; the operating current is output to the semiconductor cooling device based on the target voltage; The actual voltage of the semiconductor cooling device is determined based on the operating current, and the amplitude and direction of the operating current are controlled based on the actual voltage of the semiconductor cooling device and the target voltage.

11. A cardiopulmonary circulation system, characterized in that, The system includes a blood temperature regulating device as described in any one of claims 1-9, and / or uses a computer program in a non-volatile computer-readable storage medium as described in claim 10 to achieve assisted extracorporeal blood circulation.

Images