Analog lung for detecting ventilator physiological closed loop control function

Abstract

The application relates to a simulated lung for detecting a physiological closed-loop control function of a breathing machine, comprising a blood circulation system, in which blood circulates; a gas circulation system, in which oxygen circulates; the gas circulation system and the blood circulation system are independent of each other; a membrane oxygenator for realizing blood-oxygen exchange; the blood circulation system circulates blood through the membrane oxygenator, and the gas circulation system circulates oxygen through the membrane oxygenator; a data acquisition system connected with the blood circulation system at one end to realize blood data monitoring; and connected with the gas circulation system at the other end, wherein the gas circulation system adjusts ventilation according to the blood data. Compared with the prior art, the application combines the membrane oxygenator with the water-sealed simulated lung to detect the breathing machine with the PCLC function, so that the accuracy, reliability and safety of the breathing machine can be improved.

Description

Technical Field

[0001] This invention relates to the field of medical devices, specifically to a simulated lung with oxygenation function, and more particularly to a simulated lung for detecting the physiological closed-loop control function of a ventilator. Background Technology

[0002] Respiratory support is one of the key means of saving the lives of critically ill patients. Therefore, ventilators, as medical instruments that assist, support, or even replace human respiratory function, play a very important role in frontline clinical work such as emergency care, postoperative recovery, and intensive care. Currently used closed-loop control ventilators mainly utilize feedback control based on the mechanical properties of the lungs, such as ASV (Adaptive Support Ventilation), NAVA (Normalized Ventilation Assist System), and PAV (Proportional Assist Ventilation), all of which apply closed-loop control technology to control the pressure and / or volume output of the ventilator.

[0003] However, ventilators with physiologic closed-loop controllers (PCLC) represent a new trend in ventilator development. These ventilators, unlike traditional closed-loop ventilators, automatically adjust ventilator parameters such as tidal volume, positive end-expiratory pressure, and inhaled oxygen concentration by collecting the patient's physiological parameters, such as arterial oxygen partial pressure or blood oxygen saturation. Therefore, before PCLC ventilators are widely used clinically, there is an urgent need for a simulated lung to test the ventilator's physiological closed-loop controller function, ensuring the reliability and safety of such ventilators in clinical use.

[0004] A search revealed Chinese invention patent CN201310317397, entitled "A Simulated Human Lung Autonomous Breathing Movement Device and Control Method." This device comprises a simulated lung cavity, a spring, a traction rope, a flow sensor, a touchscreen display, a motor driver, a DC servo motor, and control circuitry. The touchscreen display inputs respiratory physiological parameters such as the inspiratory-to-expiratory ratio, respiratory rate, tidal volume, and vital capacity. The flow sensor detects the airflow through the simulated lung cavity's ventilation port. A microcontroller triggers a motor control signal based on the set respiratory parameters and the detected flow signal, which in turn controls the winding and unwinding of the traction rope, ultimately controlling the breathing movement of the simulated lung cavity. This simulated human lung breathing movement device more closely resembles human lung respiratory physiology and has high application value in scientific research, teaching, and testing of respiratory-related products. However, because this device and control method cannot simulate changes in a patient's blood oxygen content, it cannot be used for testing the PCLC function of a ventilator.

[0005] A search revealed Chinese invention publication CN201910104715, "A Cardiopulmonary Bypass System," which includes a monitoring host, a portable monitoring host, a pump, and a membrane oxygenator. The monitoring host and the portable monitoring host are electrically connected to the pump, which is connected to the membrane oxygenator via tubing. Both the pump and the membrane oxygenator are connected to blood vessels in the body via medical cannulas. When blood circulates through the blood vessels via the pump and the membrane oxygenator, the monitoring host and the portable monitoring host monitor the blood's condition. This cardiopulmonary bypass system features dual monitoring hosts that can be used separately or simultaneously. The portable monitoring host is lighter than the main monitoring host, making it convenient for emergency use, such as during first aid or inter-hospital transport. However, this system is intended for clinical cardiopulmonary bypass and, due to the lack of a simulated lung and tidal volume measurement device, cannot be used to test the PCLC function of a ventilator. Summary of the Invention

[0006] To address the shortcomings of existing technologies, the purpose of this invention is to provide a simulated lung for testing the physiological closed-loop control function of a ventilator, thereby testing the accuracy, reliability, and safety of the ventilator's PCLC function using a simulated lung with oxygenation capabilities.

[0007] According to one aspect of the present invention, a simulated lung for detecting the physiological closed-loop control function of a ventilator is provided, comprising:

[0008] The circulatory system, within which blood circulates;

[0009] A gas circulation system in which oxygen circulates; the gas circulation system is independent of the blood circulation system.

[0010] A membrane oxygenator, wherein the blood circulation system and the gas circulation system are respectively connected to the membrane oxygenator, and blood and oxygen exchange are achieved within the membrane oxygenator;

[0011] The data acquisition system is connected to the blood circulation system at one end to monitor blood data; and to the gas circulation system at the other end, which adjusts the tidal volume of the ventilator based on the blood data.

[0012] Preferably, the blood circulation system includes:

[0013] Blood bank, wherein an anticoagulant is added to the blood bank;

[0014] An air contactor, through which blood passes, can reduce the oxygen content and increase the carbon dioxide content in the bloodstream;

[0015] A blood pump is used to pump blood from the blood bank through the membrane oxygenator.

[0016] The oxygenator blood channel is located inside the membrane oxygenator. Blood flows into the membrane oxygenator from the inlet of the oxygenator blood channel for oxygenation. After oxygenation, the oxygen content of the blood is higher than when it flowed in, and then it flows out through the outlet of the oxygenator blood channel.

[0017] Preferably, the gas circulation system includes:

[0018] Water-sealed simulated lungs are used to simulate human lungs.

[0019] A flow meter, connected to the gas output end of the water-sealed simulated lung, is used to measure the tidal volume passing through the water-sealed simulated lung.

[0020] The ventilator is equipped with a physiological closed-loop controller (PCLC) function; oxygen is input from the inlet and output from the outlet of the ventilator; the ventilator is connected to the data acquisition system, and the ventilator adjusts the tidal volume according to the data received from the data acquisition system.

[0021] The oxygen channel of the oxygenator is located inside the membrane oxygenator. Oxygen is introduced into the membrane oxygenator through the inlet of the oxygen channel for oxygenation. After oxygenation, the oxygen content in the blood increases. Gases that did not enter the oxygenator and carbon dioxide discharged from the blood flow out through the outlet of the oxygen channel.

[0022] Preferably, the tidal volume measured by the flow meter is used to determine whether the physiological closed-loop controller of the ventilator is functioning properly.

[0023] Preferably, the function of the physiological closed-loop controller is to adjust the tidal volume of the ventilator according to the patient's physiological parameters PaO2 or SaO2, so that the patient's PaO2 or SaO2 is maintained at the clinically set target value.

[0024] Preferably, the adjustment of tidal volume includes:

[0025] When the blood PaO2 or SaO2 is lower than the target value set by the ventilator, the ventilator increases the tidal volume; when the blood PaO2 or SaO2 is higher than the target value set by the ventilator, the ventilator decreases the tidal volume.

[0026] Preferably, in the membrane oxygenator, blood and oxygen remain in contact without contact.

[0027] Preferably, the data acquisition system uses a probe, one end of which is connected to the outlet of the blood after oxygenation by the membrane oxygenator to detect the partial pressure of oxygen or blood oxygen saturation in the blood, and the other end is connected to the ventilator to feed back the acquired partial pressure of oxygen or blood oxygen saturation data to the ventilator.

[0028] Preferably, it also includes a constant temperature water bath, wherein the constant temperature water bath is selected by integrating a heating water pipe into the oxygenator.

[0029] Preferably, the temperature of the constant temperature water bath is controlled at 37°C to maintain the blood temperature at a normal body temperature.

[0030] Compared with the prior art, the present invention has the following beneficial effects: The present invention combines a water-sealed simulated lung with a membrane oxygenator, monitors blood oxygen saturation or oxygen partial pressure in real time through a probe, and monitors the tidal volume of the ventilator through a flow meter, which can be used to test the accuracy, reliability and safety of the PCLC function of the ventilator. Attached Figure Description

[0031] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0032] Figure 1 This is a schematic diagram of an embodiment of the simulated lung used by the present invention for detecting the physiological closed-loop control function of a ventilator.

[0033] In the diagram: 10 is the closed-loop section of the blood channel, 11 is the blood bank, 12 is the air contact chamber, 13 is the blood pump, 14 is the oxygenator blood channel, 20 is the oxygen channel circulation section, 21 is the water-sealed simulated lung, 22 is the flow meter, 23 is the ventilator, 24 is the oxygenator oxygen channel, 15 is the probe, and 30 is the constant temperature water bath. Detailed Implementation

[0034] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention. These all fall within the scope of protection of the present invention.

[0035] like Figure 1 As shown, this embodiment provides a simulated lung for testing the PCLC function of a ventilator, comprising:

[0036] The system comprises a blood circulation system, a gas circulation system, a membrane oxygenator, and a data acquisition system. Within the blood circulation system, blood circulates; within the gas circulation system, oxygen circulates. These systems operate independently. The membrane oxygenator facilitates oxygen exchange. The blood circulation system achieves blood circulation through oxygenation via the membrane oxygenator, and the gas circulation system achieves oxygen circulation through oxygenation via the membrane oxygenator. One end of the data acquisition system is connected to the blood circulation system for monitoring blood data; the other end is connected to the gas circulation system, which adjusts ventilation based on the blood data.

[0037] In a preferred embodiment, the blood circulation system includes: a blood bank 11, into which an anticoagulant is added; an air contactor 12, into which blood from the blood bank 11 is input and then output, reducing the oxygen content and increasing the carbon dioxide content in the blood flow; a blood pump 13, used to pump blood from the blood bank 11 through the air contactor 12 and a membrane oxygenator; and an oxygenator blood channel 14, disposed within the membrane oxygenator, through which blood flows into the membrane oxygenator for oxygenation. After oxygenation, the oxygen content of the blood is higher than when it flowed in, and it flows out through the outlet of the oxygenator blood channel 14.

[0038] In a preferred embodiment, the gas circulation system includes: a water-sealed simulated lung 21 for simulating human lungs; a flow meter 22 connected to the gas output end of the water-sealed simulated lung to indirectly monitor the tidal volume through the simulated lung, thereby detecting the function of the physiological closed-loop ventilator in automatically adjusting PaO2 / SaO2 by regulating the tidal volume; and a ventilator under test 23. Figure 1 (As shown in the dashed box), the ventilator has a physiological closed-loop PCLC function; oxygen is input from its inlet and output from its outlet; the ventilator is connected to a data acquisition system, and the ventilator adjusts the tidal volume according to the data received from the data acquisition system; the oxygenator oxygen channel 24 is set inside the membrane oxygenator, and oxygen is introduced into the membrane oxygenator from the inlet of the oxygenator oxygen channel 24 for oxygenation. After oxygenation, the oxygen content in the blood increases and flows out through the outlet of the oxygenator oxygen channel 24.

[0039] In a preferred embodiment, blood and oxygen do not come into direct contact in a membrane oxygenator.

[0040] As a preferred embodiment, a constant temperature water bath is used, with the heating water pipe integrated inside the oxygenator, and the water bath temperature is maintained at 37°C.

[0041] In a preferred embodiment, the data acquisition system uses a probe. One end of the probe is connected to the outlet of the blood after oxygenation by the membrane oxygenator to detect the partial pressure of oxygen or blood oxygen saturation in the blood, and the other end is connected to the ventilator. The oxygen content in the blood detected by the probe is transmitted to the ventilator.

[0042] In another embodiment of the invention, a closed-loop blood channel is included, consisting of a blood bank 11, an air contactor 12, a blood pump 13, and an oxygenator blood channel 14 connected in sequence. An open-loop oxygen channel is also included, consisting of a water-sealed simulated lung 21, a flow meter 22, and an oxygenator oxygen channel 24 connected in sequence. This open-loop oxygen channel, also referred to as the open-loop oxygen channel of the simulated lung used to detect the PCLC function of the ventilator, is connected to the ventilator body to form a closed-loop oxygen channel. One end of the probe 15 is connected to the outlet of the blood channel after oxidation by the membrane oxygenator, for monitoring the partial pressure of oxygen in the blood and blood oxygen saturation. The other end is connected to the ventilator to transmit the monitoring data.

[0043] The specific working process of this embodiment is as follows: In the closed-loop section 10 of the blood channel, the blood in the blood bank 11 containing anticoagulant flows through the air contact chamber 12 under the action of the blood pump 13. The purpose is to reduce the increasing oxygen content in the closed-loop blood flow under the working environment and increase the decreasing carbon dioxide content in the closed-loop blood flow under the working environment, so as to keep the oxygen content and carbon dioxide content in the blood within the specified range.

[0044] Then blood flows in from the inlet of the oxygenator blood channel 14, with the blood flow direction from right to left. After oxygenation, the oxygen content of the outflowing blood is higher than that of the inflowing blood. At the outlet of the oxygenator 14 blood transfusion channel, a probe 15 is installed to connect to the ventilator for detecting oxygen partial pressure or blood oxygen saturation.

[0045] Finally, the blood flows back to the blood bank. In the oxygen circulation section 20, which consists of the ventilator body with PCLC function, the ventilator 23 first starts to ventilate, and oxygen flows out from the outlet of the ventilator 23.

[0046] When the ventilator detects through probe 15 that the blood oxygen level is lower than the ventilator's set value, the ventilator increases the ventilation rate. When the ventilator detects through probe 15 that the blood oxygen level is higher than the ventilator's set value, the ventilator decreases the ventilation rate. Next, oxygen flows in from the inlet of the oxygen concentrator's oxygen tube channel 24, in the direction of left to right. After oxygenation, the carbon dioxide content in the outflowing oxygen increases. Then, the gas flows through the water-sealed simulated lung 21 and the flow meter 22; finally, it flows back into the ventilator 23.

[0047] A constant temperature water bath of 37℃ is integrated into the oxygenator to ensure that blood oxygen exchange is not affected by temperature changes.

[0048] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various modifications or variations within the scope of the claims, which do not affect the essence of the present invention. The above preferred features can be used in any combination without conflict.

Claims

1. A simulated lung for detecting the physiological closed-loop control function of a ventilator, characterized in that, include: The circulatory system, within which blood circulates; A gas circulation system in which oxygen is circulated; The gas circulation system and the blood circulation system are independent of each other; A membrane oxygenator, wherein the blood circulation system and the gas circulation system are respectively connected to the membrane oxygenator, and blood and oxygen exchange are achieved within the membrane oxygenator; The data acquisition system is connected to the blood circulation system at one end to monitor blood data. The other end is connected to the gas circulation system, which adjusts the tidal volume of the ventilator based on the blood data; The blood circulatory system includes: Blood bank, wherein an anticoagulant is added to the blood bank; An air contactor, through which blood passes, can reduce the oxygen content and increase the carbon dioxide content in the bloodstream; A blood pump is used to pump blood from the blood bank through the membrane oxygenator. An oxygenator blood channel is provided inside the membrane oxygenator. Blood flows into the membrane oxygenator from the inlet of the oxygenator blood channel for oxygenation. After oxygenation, the oxygen content of the blood is higher than when it flows in, and then it flows out through the outlet of the oxygenator blood channel. The gas circulation system includes: Water-sealed simulated lungs are used to simulate human lungs. A flow meter, connected to the gas output end of the water-sealed simulated lung, is used to measure the tidal volume passing through the water-sealed simulated lung. The ventilator is equipped with a physiological closed-loop controller (PCLC) function; oxygen is input from the inlet and output from the outlet of the ventilator; the ventilator is connected to the data acquisition system, and the ventilator adjusts the tidal volume according to the data received from the data acquisition system. The oxygen channel of the oxygenator is set inside the membrane oxygenator. Oxygen is introduced into the membrane oxygenator from the inlet of the oxygen channel for oxygenation. After oxygenation, the oxygen content in the blood increases. The gas that did not enter the oxygenator and the carbon dioxide discharged from the blood flow out through the outlet of the oxygen channel. The tidal volume measured by the flow meter is used to determine whether the physiological closed-loop controller of the ventilator is functioning properly. By combining a water-sealed simulated lung with a membrane oxygenator, and using a probe to monitor blood oxygen saturation or oxygen partial pressure in real time, and a flow meter to monitor the tidal volume of the ventilator, the accuracy, reliability, and safety of the ventilator's PCLC function can be tested.

2. The simulated lung for detecting the physiological closed-loop control function of a ventilator according to claim 1, characterized in that, The physiological closed-loop controller function is to adjust the tidal volume of the ventilator according to the patient's physiological parameters PaO2 or SaO2, so that the patient's PaO2 or SaO2 is maintained at the clinically set target value.

3. The simulated lung for detecting the physiological closed-loop control function of a ventilator according to any one of claims 2, characterized in that, The regulation of tidal volume includes: When the blood PaO2 or SaO2 is lower than the target value set by the ventilator, the ventilator increases the tidal volume; when the blood PaO2 or SaO2 is higher than the target value set by the ventilator, the ventilator decreases the tidal volume.

4. The simulated lung for detecting the physiological closed-loop control function of a ventilator according to claim 1, characterized in that, In the membrane oxygenator, blood and oxygen remain in contact without contact.

5. The simulated lung for detecting the physiological closed-loop control function of a ventilator according to claim 1, characterized in that, The data acquisition system uses a probe. One end of the probe is connected to the outlet of the blood after oxygenation by the membrane oxygenator to detect the partial pressure of oxygen or blood oxygen saturation in the blood. The other end is connected to the ventilator to feed back the acquired partial pressure of oxygen or blood oxygen saturation data to the ventilator.

6. The simulated lung for detecting the physiological closed-loop control function of a ventilator according to claim 1, characterized in that, It also includes a constant temperature water bath, wherein the constant temperature water bath is selected by integrating a heating water pipe into the oxygenator.

7. The simulated lung for detecting the physiological closed-loop control function of a ventilator according to claim 6, characterized in that, The constant temperature water bath is controlled at 37°C to maintain blood temperature at a normal body temperature.

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