Rotatable multi-sensor blood monitoring system for extracorporeal membrane oxygenation ECMO

Abstract

A blood sensor unit for an extracorporeal membrane oxygenation ECMO system includes a housing having a sampling port, a tray rotatably positioned in the housing, the tray being divided into a plurality of sectors, a plurality of blood sensors positioned on the tray, wherein each sector includes a blood sensor, and a stepper motor connected to the tray, the stepper motor being configured to rotate the tray between a plurality of positions and hold the tray at each position for a period of time. At each position, only one sector is in fluid connection with the sampling port.

Description

Technical Field

[0001] This disclosure relates to extracorporeal life support (ECLS) systems. More specifically, this disclosure relates to the monitoring of extracorporeal membrane oxygenation (ECMO) systems. Background Technology

[0002] ECLS is a treatment option for critically ill patients or patients undergoing certain surgical procedures, such as cardiac surgery. ECLS can be administered via an ECMO machine when a patient requires cardiac or pulmonary support. An ECMO machine can provide functional support to the heart and lungs, such as partial or full support.

[0003] During ECLS, patients' lactate levels can be monitored because lactate is a key indicator of tissue perfusion and oxygenation. Lactate is a key metabolite formed from anaerobic glycolysis in muscle. When lactate levels exceed approximately 2 mmol / L to 2.5 mmol / L, the patient is considered to be in a state of hyperlactatemia. This elevated lactate level may indicate inadequate oxygen delivery, metabolic disorders, or complications related to the ECLS circuit itself. Current practices for lactate monitoring in ECLS involve periodic blood sampling via venipuncture using a blood gas analyzer.

[0004] Critically ill patients are at higher risk of developing hyperlactatemia, and prolonged exposure to this condition can lead to multiple organ dysfunction syndrome and death. Due to the risk of hyperlactatemia in critically ill patients, it is recommended to run tests regularly to measure blood lactate levels when using ECLS. Summary of the Invention

[0005] In Example 1, a blood sensor unit for an extracorporeal membrane oxygenation (ECMO) system includes: a housing including a sampling port; a tray rotatably positioned in the housing, the tray being divided into multiple sectors; a plurality of blood sensors positioned on the tray, wherein each sector includes one of the blood sensors; and a stepper motor connected to the tray, the stepper motor being configured to rotate the tray between multiple positions and hold the tray at each position for a period of time, wherein at each position, only one of the sectors is in fluid connection with the sampling port.

[0006] In Example 2, the blood sensor unit of Example 1 is configured to detect the lactic acid concentration in the blood.

[0007] In Example 3, the blood sensor unit of Example 2, wherein each of the plurality of blood sensors includes a layer formed of one or a combination of Prussian blue, bovine serum albumin, lactate oxidase, polyethyleneimine, and sulfonated tetrafluoroethylene.

[0008] In Example 4, the blood sensor unit of Example 1 further includes a potentiostat selectively connected to the blood sensor in one of the plurality of sectors, which is fluidly connected to the sampling port.

[0009] In Example 5, the blood sensor unit of Example 4 further includes an actuator configured to selectively connect the potentiostat and the blood sensor in one of the plurality of sectors that is fluidly connected to the sampling port.

[0010] In Example 6, the blood sensor unit of Example 4 also includes a microcontroller unit communicatively connected to the stepper motor, the microcontroller unit being configured to control the rotation of the stepper motor.

[0011] In Example 7, the blood sensor unit of Example 6, wherein the microcontroller unit is configured to rotate the stepper motor between positions every 12 to 48 hours.

[0012] In Example 8, the blood sensor unit of Example 4 further includes a microcontroller unit communicatively connected to the potentiostat, the microcontroller unit being configured to receive signals from the plurality of blood sensors.

[0013] In Example 9, the blood sensor unit of Example 8 further includes an actuator configured to electrically connect the potentiostat and the blood sensor in one of the plurality of sectors that are fluidly connected to the sampling port.

[0014] In Example 10, the blood sensor unit of Example 1 further includes a computer communicatively connected to the plurality of blood sensors, wherein the computer is configured to store blood characteristic values ​​measured by the plurality of blood sensors.

[0015] In Example 11, the blood sensor unit of Example 10 further includes a monitor communicatively connected to the computer, wherein the monitor is configured to display blood characteristic data that has been analyzed by the computer.

[0016] In Example 12, the extracorporeal membrane oxygenation (ECMO) system includes: a blood pump; an oxygenator fluidly connected to the blood pump; and a blood sensor unit fluidly connected to the blood pump and the oxygenator, the blood sensor unit including: a tray; a plurality of blood sensors positioned on the tray; a stepper motor connected to the tray, the stepper motor being configured to move the tray such that only one of the blood sensors detects blood at a given time; and a computer communicatively connected to the blood sensor unit, wherein: the computer is configured to control the stepper motor to change which of the plurality of blood sensors detects blood after an interval; and the computer is configured to record data from the plurality of blood sensors.

[0017] In Example 13, the ECMO system of Example 12, wherein the blood sensor unit is configured to detect the lactate concentration in the blood.

[0018] In Example 14, the ECMO system of Example 12, wherein the computer is configured to rotate the stepper motor to a new blood sensor every 12 to 48 hours.

[0019] In Example 15, the ECMO system of Example 12 also includes a potentiostat electrically connected to one of the plurality of blood sensors that detect blood at a given time, and wherein the potentiostat is communicatively connected to the computer.

[0020] In Example 16, the ECMO system of Example 15 further includes a microcontroller unit communicatively connected to the potentiostat and the computer, wherein the microcontroller unit is configured to receive signals from the potentiostat and calculate blood characteristic levels.

[0021] In Example 17, the ECMO system of Example 12 also includes a monitor communicatively connected to the computer, wherein the monitor is configured to display blood characteristic data that has been analyzed by the computer.

[0022] In Example 18, a method of operating an extracorporeal membrane oxygenation (ECMO) system includes: initiating extracorporeal life support using the ECMO system, which includes a blood sensor unit; allowing blood to flow through the blood sensor unit and past a first blood sensor for a period of time; after the first period of time, replacing the first blood sensor with a second blood sensor; and allowing the blood to flow through the blood sensor unit and past the second blood sensor for the aforementioned period of time.

[0023] In Example 19, the method of Example 18 is used, wherein the blood sensor unit is configured to measure the lactic acid concentration in the blood.

[0024] In Example 20, the method of Example 18, wherein replacing the first blood sensor with the second blood sensor includes: electrically disconnecting the first blood sensor from the potentiostat using an actuator; rotating the tray holding the first blood sensor and the second blood sensor; and electrically connecting the second blood sensor to the potentiostat using the actuator.

[0025] While several embodiments have been disclosed, other embodiments of this disclosure will become apparent to those skilled in the art from the following detailed description, which illustrates and describes illustrative embodiments of this disclosure. Therefore, the accompanying drawings and detailed description should be considered illustrative rather than restrictive. Brief description of the attached figures

[0026] Figure 1 This is a schematic diagram illustrating an exemplary clinical setup for providing ECLS to a patient using an ECMO system with a blood sensor unit, consistent with various aspects of this disclosure.

[0027] Figure 2 This is a schematic diagram of the tray of the blood sensor unit, consistent with various aspects of this disclosure.

[0028] Figure 3 This is a top view of the sectors of the tray, consistent with various aspects of this disclosure.

[0029] Figures 4A-4D This is a view of the blood sensor unit, consistent with various aspects of this disclosure. Figure 4A This is an exploded view of the blood sensor unit. Figure 4B This is a top view of the bottom cover of the blood sensor unit. Figure 4C This is a top view of the tray of the blood sensor unit. Figure 4D This is a top view of the top cover of the blood sensor unit.

[0030] Figure 5 This is a schematic diagram of the driving system for the blood sensor unit, consistent with various aspects of this disclosure.

[0031] Figure 6 This is a flowchart of a method for operating an ECMO system, consistent with various aspects of this disclosure.

[0032] Figure 7 This is a perspective view of another blood sensor unit, consistent with various aspects of this disclosure.

[0033] Figure 8 This is a cross-sectional view of another blood sensor unit, such as... Figure 7 As shown in line 8-8, it conforms to various aspects of this disclosure.

[0034] Figure 9This is a top view of another tray of another blood sensor unit, consistent with various aspects of this disclosure.

[0035] Figure 10 This is a top view of another tray of another blood sensor unit, consistent with various aspects of this disclosure.

[0036] Figure 11 This is a cross-sectional view of another blood sensor unit, such as... Figure 7 As shown in line 11-11, it conforms to various aspects of this disclosure.

[0037] Figure 12 This is a top view of another tray, consistent with various aspects of this disclosure.

[0038] Figure 13 This is a schematic diagram of an actuator, consistent with various aspects of this disclosure.

[0039] While this disclosure can be made in various modifications and alternatives, specific embodiments have been shown by way of example in the accompanying drawings and described in detail below. However, it is not intended to limit this disclosure to the specific embodiments described. Rather, this disclosure is intended to cover all modifications, equivalents, and alternatives that fall within the scope of this disclosure, as defined in the appended claims. Detailed description

[0040] To facilitate understanding of the principles of this disclosure, reference is now made to the examples illustrated in the accompanying drawings, which are described below. The illustrative examples disclosed herein are not intended to be exhaustive or to limit this disclosure to the precise forms disclosed in the following detailed description. Rather, these exemplary embodiments were chosen and described to enable those skilled in the art to use their teachings. It is not impossible to use all features of a given example in all examples without departing from the scope of this disclosure. Therefore, no single drawing should be construed as having any dependency or requirement on any single component or combination of components shown therein. Furthermore, the various components depicted in a given drawing can be integrated with various components (and / or components not shown) in other components depicted therein, all of which are considered to be within the scope of this disclosure.

[0041] Figure 1This is a schematic diagram illustrating an exemplary clinical setup 100 for providing extracorporeal life support (ECLS) to a patient 102 using an extracorporeal membrane oxygenation (ECMO) system 104. In the illustrated embodiment, the ECMO system 104 includes a fluid loop having a drainage cannula 106, a blood pump 108, a blood sensor unit (BSU) 110, an oxygenator 112, and a return cannula 114, these components being fluidly connected together. The ECMO system 104 also includes a control system having a microcontroller unit (MCU) 116 and a computer 118 (with a monitor 120), these components being communicatively connected to the blood sensor unit 110. In other embodiments, the MCU 116 and the computer 118 are integrated into a single computer processing system. As shown, the BSU 110 is coupled between the blood pump 108 and the oxygenator 112 via a blood line 122.

[0042] In the illustrated embodiment, the BSU 110 is configured in series with blood tubing 122 to continuously monitor lactate levels in the blood of patient 102. As described below, the BSU 110 can operate for extended periods (e.g., 14 days), providing data for the management and treatment of lactic acidosis. Unlike conventional lactate level monitoring, the BSU 110 does not require periodic blood draws from patient 102, thus limiting the risk of infection and blood loss. Furthermore, the continuous online nature of the BSU 110 allows for the detection of rapid fluctuations in lactate levels.

[0043] In the illustrated embodiment, Figure 2 This is a schematic diagram of a BSU 110. The BSU 110 includes a housing 148, which is partially disconnected to show an internal tray 150 in fluid communication with a blood line 122. The blood line 122 is for the flow of blood from a blood pump 108 to an oxygenator 112 (both shown). Figure 1 The blood flows through the channel of BSU 110. The tray 150 is a rotatable structure divided into multiple sectors 154. The tray 150 is coupled to the blood tubing 122 to expose one of the sectors 154 to blood. Each sector 154 includes a sensor chip 156 configured to measure the quality or quantity of blood (e.g., lactate concentration). The sectors 154 are isolated from each other, and since only one sector 154 is exposed to blood at a given time, only one corresponding sensor chip 156 is exposed to blood at a given time.

[0044] In the illustrated embodiment, the BSU 110 is configured to provide a longer blood monitoring time than a single sensor chip 156 can accurately provide information for. Reasons why a single sensor chip 156 may become inaccurate over time could include, for example, protein adhesion, signal degradation, and / or sensor drift.

[0045] In some embodiments, tray 150 rotates to the next sector 154 at preset intervals, such as once per hour, twice per day, once per day, or every other day. Thus, at each interval (e.g., one hour, twelve hours, twenty-four hours, or forty-eight hours), a new sensor chip 156 is exposed to blood for monitoring purposes, such as lactate concentration. In some embodiments, the time interval for using a single sensor chip 156 is greater than or less than twenty-four hours. In some embodiments, the number of sectors 154 and sensor chips 156 is greater than or less than six. In some embodiments, tray 150 includes fourteen sensor chips 156 and rotates once per day, so that BSU 110 can accurately monitor blood externally for two consecutive weeks without disconnecting and / or reconnecting BSU 110 to blood tubing 122. This capability reduces the risk of thrombosis or leakage, thereby improving patient safety during long-term ECMO support. Although there are short periods when BSU 110 is not monitoring blood due to rotation between sectors 154, these periods are relatively negligible, and therefore BSU 110 is considered a continuous blood monitor.

[0046] Figure 3 This is a top view of sector 154 of tray 150. In the illustrated embodiment, sensor chip 156 includes an electrochemical sensor comprising a working electrode 200, a reference electrode 202, and a counter electrode 204 (collectively referred to as "electrodes 200-204"). In some embodiments, electrodes 200-204 comprise platinum due to its high biocompatibility, electrochemical stability, conductivity, and corrosion resistance. In some embodiments, the working electrode 200 comprises a layer formed of one or a combination of Prussian blue, bovine serum albumin, lactate oxidase, polyethyleneimine, and sulfonated tetrafluoroethylene (e.g., Nafion®).

[0047] In some embodiments, sensor chip 156 is a screen-printed three-electrode platinum sensor capable of detecting lactate, sold by Zimmer and Peacock AS (ZP®). In some embodiments, sensor chip 156 is configured to utilize lactate oxidase (LOx) or lactate dehydrogenase (LDH) as the enzyme. In some embodiments, sensor chip 156 is configured to directly electrochemically detect lactate by oxidizing lactate to pyruvate and hydrogen peroxide. This process immobilizes the enzyme and generates charged particles from the blood. The charged particles can be detected by amperometric method using potentiostat 206.

[0048] In the illustrated embodiment, potentiostat 206 is electrically connected to electrodes 200-204 via contact pins 208, and is electrically and / or communicatively connected to MCU 116. Tray 150 is configured to expose sample region 210 of sensor chip 156 to blood. Furthermore, tray 150 is configured to prevent contact region 212 (where the contact ends of electrodes 200-204 are located) from being exposed to blood to prevent short circuits. In some embodiments, potentiostat 206 applies a voltage between working electrode 200 and reference electrode 202. In some embodiments, the voltage has a constant value; in other embodiments, the voltage varies within a range. Potentiostat 206 measures the current flowing from working electrode 200 due to charged particles generated by lactic acid oxidation. Potentiostat 206 then sends the current value to MCU 116.

[0049] In the illustrated embodiment, MCU 116 receives signals from potentiostat 206, and uses these signals to calculate the lactate concentration in the blood in real time. In some embodiments, MCU 116 is capable of detecting lactate concentrations in the range of 0.5 mmol / L to 2.5 mmol / L in 5% increments. Lactate concentration data from MCU 116 is sent to computer 118. Computer 118 stores, analyzes, and / or displays lactate concentrations changing over time. In some embodiments, computer 118 analyzes lactate concentrations to determine patterns and / or trends in lactate concentration over time (e.g., rate of change of lactate concentration) and / or summarizes lactate concentration data for a given time period. In some embodiments, the analysis results are compared to predetermined and / or personalized criteria, and if the comparison results indicate so, computer 118 provides feedback to the clinician (e.g., alarms, warnings, or other communications). For example, if the lactate concentration is high and trending upwards, this can be detected on monitor 120 (shown on screen 120). Figure 1 A warning is displayed on the screen, accompanied by an alarm sound.

[0050] Figure 4A This is an exploded view of the BSU 110. In the illustrated embodiment, the BSU 110 includes a bottom cover 250, a tray 150, a top cover 252, and an actuator assembly 254. In some embodiments, the external structure of the bottom cover 250, tray 150, top cover 252, and actuator assembly 254 (shown in the diagram) Figure 13 The actuator assembly 254 is made of a polymer material (e.g., polycarbonate). In some embodiments, the actuator assembly 254 is connected to the MCU 116 and / or the computer 118 (shown in the figure). Figure 3A solenoid is used for communication and control. When the BSU is assembled, the bottom cover 250 and actuator assembly 254 are rigidly connected to the top cover 252 (e.g., using fasteners, pins, and / or adhesives), thus fixing the covers 250, 252, and actuator assembly 254 relative to each other. However, the tray 150 is located in the cavity formed between the covers 250, 252. Therefore, the tray 150 is rotatable within the BSU 110. Although... Figure 4A The image shows one size of the BSU 110, but different sizes can be built to fit patients of different sizes (e.g., one size for adults and another for children).

[0051] Figure 4B This is a top view of the bottom cover 250. In the illustrated embodiment, the bottom cover 250 includes a flat, circular base 256 with an edge 258. The edge 258 extends upward from the periphery of the base 256. The base 256 defines an outlet port 260 located near the edge 258 and a centrally located drive port 262. The outlet port 260 connects to the blood conduit 122 (shown in the diagram). Figure 2 A fluid connection allows blood to flow out of the BSU 110. Drive port 262 allows the drive shaft (shown) Figure 5 It passes through the bottom cover 250 and is connected to the tray 150.

[0052] Figure 4C This is a top view of tray 150. In the illustrated embodiment, tray 150 includes a flat, circular bed 264 with a circular edge 266, radial dividers 268, and railings 270 extending upward from the bed 264. The edge 266 and dividers 268 separate sectors 154 from each other. Each sector 154 includes four railings 270 for positioning and securing sensor chips 156 (shown in the diagram). Figure 3 Each sensor chip 156 has a fence 270 on each side. In some embodiments, each sector 154 includes a single sensor chip 156, while in other embodiments, each sector 154 includes multiple sensor chips 156 to measure a variety of blood properties.

[0053] In the illustrated embodiment, each sector 154 further includes a through-hole 272 defined by a bed 264. Each sector 154 is fluidly connected to an outlet port 260 via a corresponding through-hole 272, allowing blood to flow through the tray 150. As blood flows through the tray 150, a portion of the blood contacts a corresponding sensor chip 156, allowing measurement of blood characteristics. In some embodiments, when the sector 154 is in the position for measuring blood characteristics, the through-hole 272 is connected to the outlet port 260 (shown in the diagram). Figure 4BAlignment. In other embodiments, when sector 154 is in the position for measuring blood characteristics, through-hole 272 is offset from outlet port 260. In some embodiments, the diameter of through-hole 272 is the same as the diameter of outlet port 260. In other embodiments, the diameter of through-hole 272 is smaller than the diameter of outlet port 260.

[0054] In the illustrated embodiment, the dividers 268 intersect at the center of the bed 264. Therefore, a central hub 274 exists, allowing the drive shaft (shown) Figure 5 ) is connected to tray 150. In some embodiments, the top surface of edge 266 and / or divider 268 serves as a seal and is connected to top cover 252 (shown) Figure 4A This seal means that at any given time only one sector 154 is connected to the outlet port 260 (shown). Figure 4B ) and ingress port 276 (shown) Figure 4D Fluid connection. This seal prevents blood from leaking into adjacent sectors 154 except for the sector 154 where blood characteristics are measured. In some embodiments, the top surface of edge 266 and / or separator 268 includes a flexible seal or gasket (not shown) to enhance the seal of sector 154.

[0055] Figure 4D This is a top view of the top cover 252. In the illustrated embodiment, the top cover 252 is flat and round, defining an inlet port 276 located near its periphery. The top cover 252 also defines an actuator port 278 located between its center and the inlet port 276. The inlet port 276 is connected to the blood conduit 122 (shown in the diagram). Figure 2 A fluid connection allows blood to flow into the BSU 110.

[0056] In the illustrated embodiment, actuator port 278 allows actuator assembly 254 (shown) Figure 4A ) through top cover 252. When sector 154 (shown) Figure 4C When the actuator assembly 254 is in the position for measuring blood characteristics, it will contact pin 208 (shown in the image). Figure 3 Connect to electrode 200-204 (shown) Figure 3 When a rotating tray of 150° is required (shown) Figure 4C When the actuator assembly 254 releases contact pin 208, this will cause the potentiostat 206 (shown) Figure 3 ) and the used sensor chip 156 (shown) Figure 3 Disconnect. After tray 150 rotates to the next sector 154, actuator assembly 254 can connect contact pin 208 to the new sensor chip 156. Therefore, only one potentiostat 206 is needed, instead of one for each sector 154.

[0057] In the illustrated embodiment, inlet port 276 allows blood to flow through top cover 252, and inlet port 276 is connected to sector 154 at the blood characteristic measurement location and its corresponding through-hole 272 (shown). Figure 4C Fluid connection. In some embodiments, when sector 154 is in the position for measuring blood characteristics, inlet port 276 is aligned with the corresponding through-hole 272. In other embodiments, when sector 154 is in the position for measuring blood characteristics, inlet port 276 is offset from through-hole 272. In some embodiments, the diameter of inlet port 276 is the same as the diameter of outlet port 260 and / or through-hole 272. In other embodiments, the diameter of inlet port 276 is larger than the diameter of through-hole 272.

[0058] Figure 5 This is a schematic diagram of the drive system of the BSU 110. In the illustrated embodiment, the tray 150 is rotatably positioned within the housing 148 (including the bottom cover 250 and the top cover 252 fixed together, both shown). Figure 4A The tray 150 is connected to the drive shaft 302 of the stepper motor 304, so the rotational position of the tray 150 is physically controlled by the stepper motor 304. Furthermore, the actuator assembly 254 includes electrodes 200-204 (shown in diagram) configured to contact the sensor chip 156 at the location for measuring blood flow. Figure 3 Contact pin 208.

[0059] Stepper motor 304 and actuator assembly 254 are communicatively connected via cables 306 and 308, respectively. Therefore, stepper motor 304 and actuator assembly 254 are controlled by codes sent from MCU 116 and / or computer 118. Thus, tray 150 can be used in ECMO system 104 (shown in diagram 104). Figure 1 The ECMO system 104 can be positioned and repositioned as needed during operation. Therefore, the ECMO system 104 can continuously, accurately, and reliably measure blood characteristics (such as lactate concentration) for extended periods without permanently drawing blood from the patient. Furthermore, signals from the sensor chip 156 are transmitted to the MCU 116 and computer 118 via the actuator assembly 254 and cable 306.

[0060] Figure 6 This is a flowchart of method 350 for operating the ECMO system 104. When discussing method 350, reference will be made to previous discussions on... Figure 1-5 Some components are discussed.

[0061] In the illustrated embodiment, method 350 begins at operation 352, where the BSU 110 is connected to other components in the ECMO system 104. At operation 354, ECLS is activated, thus allowing blood to flow through the BSU 110. At operation 356, blood characteristics are monitored using a first sensor chip 156. The results are sent to a computer 118, which displays the results and further analysis of the data on a monitor 120. At operation 358, for example, after 24 hours of ECLS, the first sensor chip 156 is rotated out of the monitoring position, and a second sensor chip 156 is rotated into the monitoring position. At operation 360, blood characteristics are monitored using the second sensor chip 156. The results are sent to the computer 118, which displays the results and analysis of the data on a monitor 120.

[0062] Figure 7 This is a perspective view of another blood sensor unit (BSU) 400. In the illustrated embodiment, some features and functions of the BSU 400 are the same as those of the BSU 110 (shown in the diagram). Figure 5 The pipe 402 is identical or similar to the housing 404 of the BSU 400, although other features and functions differ. For example, pipe 402 extends through the front surface of the housing 404 of the BSU 400. Pipe 402 includes an inlet end 406 and an outlet end 408, and pipe 402 is in fluid communication with the interior of the housing 404. A rotatable tray (shown) Figure 8 The actuator 410 is rotatably positioned within the housing 404 and is connected to the front of the housing 404. The inlet end 406 and the outlet end 408 are configured to couple to the blood line 122 (shown in diagram 122). Figure 1 To complete the blood circulation.

[0063] Figure 8 This is a cross-sectional view of the BSU 400, as shown below. Figure 7 As shown by line 8-8 in the middle. Therefore, Figure 8 A cut plane extending from the front to the rear of the BSU 400, parallel to the conduit 402, is shown. In the illustrated embodiment, the conduit 402 defines a sampling port 450, which is in fluid communication with a sampling port 452 defined by a housing 404. Therefore, the interior of the housing 404 is in fluid communication with the interior of the conduit 402, allowing blood in the conduit 402 to flow into the housing 404 and interact with the sensor chip 156 on the tray 454.

[0064] Figure 9 This is a top view of tray 454. In the illustrated embodiment, tray 454 includes an inner seal 500, an outer seal 502, and a plurality of sector seals 504 extending between the inner seal 500 and the outer seal 502. Seals 500-504 are connected to housing 404 (shown in the diagram). Figure 8 The interaction of these components creates a fluid-isolated array of 505 compartments to control the BSU 400 (shown in the diagram). Figure 8The fluid inside the sensor chip 156. Each sector seal 504 extends along the boundary 506 of sector 508, and the outer seal 502 is positioned outside the outer end of the sensor chip 156. The inner seal 500 is positioned between the sample area 210 and the contact area 212. In some embodiments, seals 500-504 are components of a monolithic gasket.

[0065] Therefore, the fluid in housing 404 cannot communicate between different sectors 508, nor with the innermost part of BSU 400, which is the contact area 212 and actuator assembly 410 (shown in diagram). Figure 7 The sample areas 210 are each located in compartment 505, so when tray 454 rotates a given sensor chip 156 to the sampling position, its corresponding sample area 210 is located in the tube 402 (shown in the diagram). Figure 8 Fluid connection.

[0066] In some embodiments, to prevent air bubbles from entering the conduit 402, each compartment 505 is pre-filled with a filler material, such as a saline solution. Therefore, when the tray 454 rotates a given compartment 505 to the sampling position, blood flow displaces the filler material. In some embodiments, there is a slight delay in accurate blood measurement until the filler material is removed from above the sample area 210.

[0067] In some embodiments, BSU 400 (shown) Figure 8 ) includes two potentiostats 206 (shown) Figure 3 ) and two actuator assemblies 410 (shown) Figure 7 In such embodiments, the second potentiostat 206 and the second actuator 410 are positioned to connect to the next sensor chip 156 (i.e., the sensor chip 156 that is not yet used but will be rotated in after the current sensor chip 156 has been rotated out). In such embodiments, the filling material is a saline solution measured by the next sensor chip 156. Therefore, the computer 118 (shown) Figure 2 The data from the next sensor chip 156 is used as a calibration signal because the output of the next sensor chip 156 is measuring a known fluid. In other embodiments, the BSU 400 includes a reference sensor chip 156 that is not configured to move to the location for measuring blood (e.g., the reference sensor chip 156 is not located on tray 454). This reference sensor chip 156 can measure sample fluids (e.g., physiological saline solutions) during BSU 400 operation as a background measurement used by computer 118 to compensate for signal drift.

[0068] Figure 10This is a top view of another tray 600. In the illustrated embodiment, tray 600 includes an inner seal 602 and a plurality of sample seals 604 surrounding each sample region 210 of each sensor chip 156. Therefore, blood is allowed to contact sample regions 210 but is prevented from reaching contact regions 212.

[0069] Figure 11 This is another cross-sectional view of the BSU 400, such as... Figure 7 As shown by line 11-11 in the middle. Therefore, Figure 11 A cut plane extending from the front to the rear of the BSU400, perpendicular to the conduit 402, is shown. In the illustrated embodiment, the outer seal 608 is positioned between the outer periphery of the tray 600 and the housing 404. In some embodiments, the space between the inner seal 602 and the outer seal 608 is filled with a liquid (e.g., a saline solution) to prevent gas from entering the conduit 402.

[0070] Figure 12 This is a top view of another tray 650. In the illustrated embodiment, the sensor chip 156 is encapsulated in a solid filler material 652 (e.g., an electrically insulating polymer), with only its sample area 210 and contact area 212 exposed. In some embodiments, these areas are surrounded by seals 654 and 656, respectively. Thus, the contact area 212 can remain fluid-free, while the sample area 210 can measure blood.

[0071] Figure 13 This is a schematic diagram of actuator assembly 410. In the illustrated embodiment, the actuator assembly includes actuator 700, bias member 702, outer structure 704, yoke 706, operating pin 708, reference pin 710, and counter pin 712. Outer structure 704 is connected to housing 148. Actuator 700 and bias member 702 are connected at one end to outer structure 704 and at the other end to yoke 706. Yoke 706 includes pins 708-712 configured to electrically connect to contacts 200-204 of sensor chip 156, respectively.

[0072] In the illustrated embodiment, biasing member 702 applies a force to yoke 706, pushing pins 708-712 toward contacts 200-204. When it is necessary to disconnect pins 708-712 from contacts 200-204, actuator 700 is activated, overcoming the force of biasing member 702. As a result, actuator 700 pulls yoke 706 upward away from sensor chip 156 so that the old sensor chip 156 can be replaced with a new one. Once the new sensor chip 156 is in place, actuator 700 is deactivated, and biasing member 702 pushes yoke 706 downward. Thus, pins 708-712 are electrically connected to contacts 200-204 of the new sensor chip 156.

[0073] As is well known, methods comprising one or more steps are not limited by the order listed in the claims unless expressly or implicitly stated in the specification or the claims themselves. It is also clear that the methods shown are merely a few of many disclosed examples, and certain steps may be added or omitted without departing from the scope of this disclosure. Such steps may include combinations of devices, systems, methods, or components thereof known, conventional, and traditional in the art.

[0074] The connecting lines shown in the various figures herein are intended to illustrate exemplary functional relationships and / or physical couplings between various elements. It should be noted that many alternative or additional functional relationships or physical connections may exist in actual systems. However, any element that causes any benefit, advantage, problem-solving, or makes any benefit, advantage, or solution occur or become more apparent should not be construed as a critical, necessary, or indispensable feature or element. Therefore, the scope should be limited only by the appended claims, where references to elements in the singular form are not intended to mean "one and only one," but rather "one or more" unless explicitly stated otherwise. Furthermore, when phrases such as "at least one of A, B, or C" are used in the claims, it is intended to be interpreted as meaning that A may exist alone in an embodiment, B may exist alone in an embodiment, C may exist alone in an embodiment, or any combination of A, B, or C may exist in a single embodiment; for example, A and B, A and C, B and C, or A and B and C. The terms “coupled,” “connected,” “attached,” etc., and variations thereof are used to describe arrangements that include two or more components in direct physical contact, as well as arrangements in which two or more components are not in direct contact with each other (e.g., components are “coupled” through at least a third component) but still cooperate or interact with each other.

[0075] In the detailed description herein, references to "an embodiment," "an embodiment," "an example embodiment," etc., indicate that the described embodiment may include a particular feature, structure, or characteristic, but not every embodiment necessarily includes that particular feature, structure, or characteristic. Furthermore, such phrases do not necessarily refer to the same embodiment. Moreover, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is believed that, to the knowledge of those skilled in the art, such feature, structure, or characteristic may affect other embodiments having the benefits of this disclosure, whether explicitly described or not. Upon reading the description, those skilled in the art will understand how to implement this disclosure in alternative embodiments.

[0076] Various modifications and additions can be made to the exemplary embodiments discussed above without departing from the scope of this disclosure. For example, while the above embodiments relate to specific features, the scope of this disclosure also includes embodiments with different combinations of features and those that do not include all described features. Therefore, the scope of this disclosure is intended to cover all such alternatives, modifications, and variations falling within the scope of the claims, as well as all their equivalents.

Claims

1. A blood sensor unit for an extracorporeal membrane oxygenation (ECMO) system, comprising: Including the housing of the sampling port; A tray rotatably positioned within the housing, the tray being divided into multiple sectors; Multiple blood sensors are positioned on the tray, wherein each sector includes one blood sensor; and A stepper motor is connected to the tray, the stepper motor being configured to rotate the tray between multiple positions and hold the tray at each position for a period of time, wherein at each position, only one sector is fluidly connected to the sampling port.

2. The blood sensor unit according to claim 1, characterized in that, The blood sensor unit is configured to detect the concentration of lactic acid in the blood.

3. The blood sensor unit according to claim 2, characterized in that, Each of the plurality of blood sensors comprises a layer formed of one or a combination of Prussian blue, bovine serum albumin, lactate oxidase, polyethyleneimine, and sulfonated tetrafluoroethylene.

4. The blood sensor unit of claim 1 further includes a potentiostat selectively connected to the blood sensor in one of the plurality of sectors in fluid connection with the sampling port.

5. The blood sensor unit of claim 4, further comprising an actuator configured to selectively connect the potentiostat and the blood sensor in one of the plurality of sectors in fluid connection with the sampling port.

6. The blood sensor unit according to claim 4 further includes a microcontroller unit communicatively connected to the stepper motor, the microcontroller unit being configured to control the rotation of the stepper motor.

7. The blood sensor unit according to claim 6, characterized in that, The microcontroller unit is configured to rotate the stepper motor between positions every 12 to 48 hours.

8. The blood sensor unit according to claim 4 further includes a microcontroller unit communicatively connected to the potentiostat, the microcontroller unit being configured to receive signals from the plurality of blood sensors.

9. The blood sensor unit of claim 8, further comprising an actuator configured to electrically connect the potentiostat and the blood sensor in one of the plurality of sectors fluidly connected to the sampling port.

10. The blood sensor unit of claim 1, further comprising a computer communicatively connected to the plurality of blood sensors, wherein the computer is configured to store blood characteristic values ​​measured by the plurality of blood sensors.

11. The blood sensor unit of claim 10, further comprising a monitor communicatively connected to the computer, wherein the monitor is configured to display blood characteristic data analyzed by the computer.

12. An extracorporeal membrane oxygenation (ECMO) system, comprising: Blood pump; An oxygenator fluidly connected to the blood pump; A blood sensor unit fluidly connected to the blood pump and the oxygenator, the blood sensor unit comprising: tray; Multiple blood sensors positioned on the tray; A stepper motor connected to the tray is configured to move the tray such that only one of the blood sensors detects blood at a given time. A computer communicatively connected to the blood sensor unit, wherein: the computer is configured to control the stepper motor to change which of the plurality of blood sensors detects the blood after an interval; and the computer is configured to record data from the plurality of blood sensors.

13. The ECMO system according to claim 12, characterized in that, The blood sensor unit is configured to detect the lactic acid concentration in the blood.

14. The ECMO system according to claim 12, characterized in that, The computer is configured to rotate the stepper motor to a new blood sensor every 12 to 48 hours.

15. The ECMO system of claim 12, further comprising a potentiostat electrically connected to one of the plurality of blood sensors that detect blood at a given time, and wherein the potentiostat is communicatively connected to the computer.

16. The ECMO system of claim 15 further includes a microcontroller unit communicatively connected to the potentiostat and the computer, wherein the microcontroller unit is configured to receive signals from the potentiostat and calculate blood characteristic levels.

17. The ECMO system of claim 12, further comprising a monitor communicatively connected to the computer, wherein the monitor is configured to display blood characteristic data analyzed by the computer.

18. A method for operating an extracorporeal membrane oxygenation (ECMO) system, comprising: Initiate extracorporeal life support using the ECMO system, which includes a blood sensor unit; Blood is allowed to flow through the blood sensor unit and pass through the first blood sensor for a period of time; After the first time period, the first blood sensor is replaced with a second blood sensor; and The blood is allowed to flow through the blood sensor unit and pass through the second blood sensor for a certain period of time.

19. The method according to claim 18, characterized in that, The blood sensor unit is configured to measure the lactic acid concentration in the blood.

20. The method according to claim 18, characterized in that, Replacing the first blood sensor with the second blood sensor includes: Use an actuator to electrically disconnect the first blood sensor from the potentiostat; Rotate the tray that holds the first blood sensor and the second blood sensor; The second blood sensor is electrically connected to the potentiostat using the actuator.

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