TW201907965A - Extracorporeal life support system - Google Patents

Abstract

The present invention provides a method, system, and apparatus that can substantially reduce the recirculation of venovenous extracorporeal membrane oxygenation (VV ECMO) associated with the two-site, single-lumen cannulation approach. Actively-controlled flow regulators comprising balloon, occluder and reservoir can be individually or collectively equipped on the drainage and/or infusion cannulas to accomplish the goal of maximizing VV ECMO support efficacy. Three specific embodiments are introduced to illustrate the practical enforcement of the proposed blood flow control in reference to the heart rhythm, aiming at achieving the maximal reduction of oxygenated blood flow recirculating back to the VV ECMO circuit.

Description

Extracorporeal life support system

The invention relates to an in vitro life support system, which mainly uses an actively controlled flow regulation method in a Venoveous Extra-Corporeal Membrane Oxygenation (VV ECMO) system to prevent oxygenated blood from being recirculated through a drainage conduit. Go back to the ECMO loop. In particular, the present invention uses an electrocardiographic signal (ECG) as a reference for the active control time of the active control flow regulation system to further improve recirculation through hysteresis or acceleration of the in-duct flow. The goal is to allow the maximum amount of hyperoxic blood to flow into the right ventricle during diastole and tricuspid opening; while the heart contracts, and the high oxygenated blood perfusion in the ECMO circuit is reduced to the right atrium and vena cava when the tricuspid valve is closed. At the same time, it can cause a large number of low oxygenated veins to return to the ECMO circuit.

Since the avian influenza pandemic in 1992, the world has used an extracorporeal membrane oxygenation (ECMO) system to rescue severe respiratory diseases, such as Acute Respiratory Distress Symdrome (ARDS), which is gradually increasing in usage. . Currently, approximately 40% of annual ECMO use is associated with the treatment of acute respiratory distress syndrome or other serious respiratory diseases, where intubation methods and design are critical for effective treatment of lung disease.

ECMO is usually divided into two types of intubation types: intravenous-arterial ECMO (VA ECMO) and intravenous-venous ECMO (VV ECMO). Clinically, VA ECMO is mostly used to treat patients with heart failure, while VV ECMO is used to treat patients with respiratory failure. The VV ECMO's extracorporeal pulmonary circulatory circuit originates from the use of a single-lumen catheter for cannulation at both sites, the most common of which is the insertion of a drainage catheter, Superior Vena, in the inferior vena cava (IVC). Insert a perfusion catheter into Cava, SVC). The most common type of VV ECMO, the drainage catheter is inserted from the groin and pushed forward into the inferior vena cava, while the perfusion catheter is inserted by the jugular vein and then pushed forward into the superior vena cava. The catheter will converge near the right atrium (RA) area. Since the tip of both the drainage catheter and the perfusion catheter are located close together, a substantial portion of the hyperoxic blood in the perfusion catheter will be drawn into the drainage catheter rather than into the right atrium, producing a type called Recirculation, which compromises the efficacy of VV ECMO. Recirculation rates are also generally increased as ECMO flow increases, especially when severely damaged lungs require larger ECMO perfusion assistance. When recirculation occurs, the efficacy of VV ECMO is not only affected, but also causes the blood to stay longer in the ECMO circuit, causing more complications due to damage of blood cells, which is a clinically unpleasant situation. . For example, when blood cells are recirculated in the ECMO loop for a longer period of time, more blood cells are lysed, especially in the narrow fiber channel of the Oxygenator, causing concurrent bleeding or thromboembolism. The disease leads to the need to use higher doses of heparin anticoagulant.

A number of solutions have been proposed to reduce the VV ECMO recirculation rate, with practical implementation focusing on improved catheter design and associated intubation methods. In combination with different types of catheter design and intubation methods, VV ECMO clinically has four types of intubation: 1) intubation in two locations using a single lumen catheter, and 2) intubation in a single site using a dual lumen catheter. 3) Intubation was performed at both sites using a dual chamber catheter, and 4) can be intubated at three sites using a single lumen catheter. In recent years, the type of intubation of a dual-chamber catheter at a single site has been achieved through the approval of a commercially available Avalon catheter, and because this catheter can reduce recirculation rates and provide better mobility for the patient to help the lungs The advantages of faster recovery are gradually gaining popularity in Europe and the United States.

All of the above-described intubation patterns use passive design concepts without active control elements to reduce the recirculation rate. It is worth noting that the right ventricle can only receive perfusion of oxygenated blood when the heart is dilated and the tricuspid valve is open. When the heart contracts and the tricuspid valve is closed, regardless of how the tip of the perfusion catheter is placed near the entrance to the tricuspid valve, the perfused oxygenated blood cannot enter the right ventricle, which limits the performance of all passive catheters. The root cause. In the inventor's laboratory, a specially designed pulmonary circulation biomimetic physiological test platform has been developed to measure the recirculation rate of VV ECMO. The experiment found that when the ECMO flow rate is 3.5 liters per minute, the traditional use of single-chamber catheters in the two-part cannula type, the recirculation rate can be as high as 40-50%, and the Avalon double-chamber catheter is used in a single The type of site cannula has a recirculation rate of about 20 to 25%. Therefore, there is still considerable room for further improvement in the design, so that patients can get better lung VV ECMO treatment.

Patients with ECMO are usually sedated and bedridden in the intensive care unit (ICU), although the advantage of using a dual-chamber catheter to intubate a single site is that the patient can move around and speed up recovery, but in practical clinical applications It is difficult to achieve this advantage. In fact, in the vast majority of intensive care units around the world, the caregivers and staff in the intensive care unit cannot allow ECMO patients to get out of bed and walk around the corridors around the intensive care unit routinely and safely.

Usually, the diameter of the ECMO catheter is limited, because the catheter with too large diameter is difficult to insert into the blood vessel, and the blood vessel may be damaged by the operation inside the blood vessel, and the vascular chamber may become narrow after the catheter is removed. complication. The double-chamber conduits with both the perfusion channel and the drainage channel are essentially smaller than the flow path diameter of the single-chamber conduit. Inevitably, higher flow resistance and wall shear stress will exist in the double Among the chamber catheters, therefore, when the blood flow flows out of the narrower drainage channel of the double chamber catheter and then flows into the narrower perfusion channel, more blood cells are damaged. In fact, ECMO flow is limited by high flow resistance in dual chamber catheters, which is undesirable for patients with severe respiratory failure who are in urgent need of greater ECMO flow assistance.

The present invention employs a specially designed dual chamber catheter dual site cannula version that uses ECG signals as a basis for improved recirculation control systems to further reduce recirculation rates and will be described later. It should first be noted that the present invention differs from the previously defined classification of the catheter chamber. The dual chamber in the present invention is defined as a tubular unit composed of an air flow path and a blood flow path, wherein the blood flow path is horizontal. The cross section is much larger than the cross section of the air flow passage. In fact, the blood flow impedance of the dual chamber catheter of the present invention is comparable to that of the single lumen catheter described above, and therefore, hemodynamically has the dual advantages of higher blood flow assistance and lower flow resistance. Due to the large blood flow channels in the catheter, the shear stress of the tubular flow is greatly reduced, resulting in less damage to the blood cells, as well as the clinical management advantages of requiring less heparin and anticoagulation.

The flow rate distribution of the drainage and perfusion is adjusted according to the switch of the tricuspid valve. Theoretically, the recirculation rate of the VV ECMO can be minimized to the extent that the prior art cannot achieve. The inventors believe that it would be more desirable to further reduce the recirculation rate of the current dual lumen catheter in a single partial cannula type while at the same time expanding the secondary range of ECMO flow under lower hematocytic damage. Treatment programs. If the time and blood flow characteristics associated with tricuspid valve motion can be considered, the VV ECMO assisted effect can be further improved by actuation of an actively controlled actuator mounted on the catheter, allowing the sick lungs to rest more fully. And getting a faster recovery greatly reduces the time patients use ECMO and stay in the intensive care unit, which will really benefit patients. Rehabilitation treatment to help patients accelerate lung recovery can be performed after the patient is removed from ECMO and removed from the intensive care unit.

The present invention relates to an innovative design of a blood flow regulation system that enhances the efficiency of venous-venous extracorporeal membrane oxygenation (VV ECMO). This actively controlled ECMO system includes a drainage catheter, a perfusion catheter, a blood pump, an oxygenator, and a pneumatic actuator controlled by an electrical signal. The drainage catheter assembly for draining hypoxemia from the vena cava to the ECMO system includes: a drainage catheter (Drainage Cannula), a Compliant Reservoir, an obturator at the drain end (Occluder), and a first balloon ( First Balloon). The perfusion catheter assembly for perfusing the hyperoxic blood of the ECMO into the vena cava or the right atrium includes: an infusion cannula, a cis porter, a perfusion end occluder, and a second balloon. These active components: balloon, occluder and passive component: the compliant volume reservoir can be used in whole or in part in the design of the control system, and use the ECG signal as a trigger reference for the system control logic to form a flow regulating component. Catheter assembly. Intermittent control of venous return and ECMO-driven drainage and perfusion according to the opening and closing of the tricuspid valve allows the maximum amount of hyperoxia to be perfused into the right ventricle and subsequently into the pulmonary circulation. The VV ECMO regulated by this electrical signal can significantly reduce the recirculation of high oxygenated blood reflux into the ECMO circuit and reduce the oxygenation load of the patient's lungs. Furthermore, reducing blood recirculation also reduces the residence time of blood in the ECMO circuit, helping to reduce the risk of hemocytic damage such as hemolysis, thrombosis, and stroke.

The drainage catheter or perfusion catheter of the present invention comprises an inflatable balloon that can be coated on a portion of the outer surface of the catheter, or otherwise designed by combining a balloon catheter with the drainage catheter or perfusion catheter. Functional Requirements. The balloon material must be durable and biocompatible and made of a deformable or malleable elastomeric material. When the balloon is deflated, the balloon contracts into a small profile to reduce flow resistance. When the balloon is inflated, the balloon expands against the vessel wall or immediately adjacent to the vessel wall, thereby occluding the blood flow channel. The intravascular catheter and balloon assembly is placed in a large venous blood vessel to be responsible for drainage or perfusion of blood. By controlling the expansion and contraction of the balloon on the catheter, the time interval and return flow of the upper vena cava or the inferior vena cava returning to the right atrium can be regulated.

The catheter of the present invention may further be provided with a configurable occluder on the catheter that is external to the patient's body. An occluder is a mechanism that compresses the cross-sectional area of a tube to reduce flow, in other words, it slows the flow of internal tube flow by increasing the impedance of the flow. Alternatively, an internal balloon or flexible membrane can be utilized to provide internal flow impedance and can be considered a wide range of occluders. By squeezing the occluder to achieve different degrees of occlusion, time points, and time intervals, it is possible to regulate the blood flow channel within the catheter with a fully open, partially open, or closed tense throughout the time series. It is therefore possible to regulate the time interval and flow rate at which the venous return blood is drawn into the ECMO inflow end, and the time interval and flow rate of the high oxygenated blood flowing out from the ECMO outflow end.

The function of the blood reservoir is similar to the capacitance on the circuit, used to store or return blood, and is combined with the ECMO flow path, in order to provide when the balloon or occluder in the circuit is activated. The ECMO blood pump operates stably and continuously. Passive volumetric blood reservoirs can be made from elastic materials that function like the resilience of human blood vessels. The design can also construct an active volumetric reservoir similar to a Displacement Pump, which is controlled by an external drive system to control the volume change of the volumetric reservoir. The volumetric blood reservoir can be connected in series or in parallel with the flow channel. The advantage of a passive volumetric reservoir is that it has a simple and streamlined flow path design. However, in some cases, the device actively aligns the volume of the blood reservoir to actively control the fluid volume of the fluid into and out of the volumetric reservoir. Helps regulate the flow in the ECMO circuit.

Both the balloon and the occluder use an ECG signal as a reference signal for the control trigger to activate the balloon and occluder actuation. As long as the time of the tricuspid opening and closing can be properly matched in the manipulation time, the expansion and contraction of the balloon and the opening and closing of the occluder can be manipulated separately or combined. The purpose of such manipulation is to store the maximum amount of hyperoxic blood in the right atrium before the tricuspid opening is opened (prepared to be filled to the right ventricle during diastole), however, when the systolic tricuspid regurgitation is closed, The venous return of oxygen that consumes oxygen enters the ECMO circuit in large quantities. In addition, the compliant reservoir is actuated with the occluder to compensate for the obstruction of flow within the ECMO circuit when the occluder is closed, and the follow-up reservoir is like a booster when the occluder is opened in the next phase. The blood stored and boosted in the blood reservoir can be accelerated back into the ECMO circuit. The invention uses a VV ECMO active flow control system with an ECG signal as a control reference, which can greatly reduce the recirculation rate in the conventional ECMO loop without reducing the flow rate of the ECMO.

The focus of this control method is to regulate the flow of venous return and ECMO catheters based on the movement of the tricuspid valve in order to reduce the disadvantages of VV ECMO recycling. Figures 1 and 2 show the position of each control element, respectively, and the mode of operation of each control element as the heart contracts and relaxes in order to reduce the recirculation rate. 1 and 2 are schematic illustrations of a VV ECMO loop and pulmonary circulation depicted in accordance with an embodiment of the present invention. The extracorporeal life support system 20 is comprised of an oxygenator 201, a blood pump 202, a perfusion catheter assembly 21, and a drainage catheter assembly 22. The oxygenator 201 and the blood pump 202 are disposed outside the patient. Additionally, the perfusion catheter assembly 21 is placed in a position opposite the drainage catheter assembly 22. In one embodiment of the invention, the drainage catheter assembly 22 can include a drainage balloon 208, or a drainage obturator 210 or a drainage reservoir 212 can be added, or both can be retrofitted. In other embodiments of the invention, the perfusion tube assembly 21 can include a perfusion end balloon 207, or a perfusion end occluder 205 or a perfusion end compliant reservoir 203, or both.

In both figures, the drainage catheter 209 is placed in the inferior vena cava 104 and the drainage end balloon 208 is placed on the drainage catheter 209. The drainage end occluder 210 and the compliant blood reservoir 212 are disposed outside the body of the patient and are connected to the ECMO drainage catheter 211. Similarly, the perfusion catheter 206, the perfusion balloon 207, is also placed in the superior vena cava in a similar manner, while the perfusion end occluder 205 and the compliant reservoir 203 are disposed outside of the patient's body. It should be noted that in the surgical setting, the perfusion catheter 206 and the drainage catheter 209 can exchange the position of the cannula with each other, as opposed to the intubation approach disclosed in Figures 1 and 2. In practical applications, the catheter assemblies 21, 22 can also be actively controlled using the control methods and hardware systems provided herein.

The control actions of the above flow regulation system will be described below:

Diastolic phase:

1. During diastole, the tricuspid valve 103 between the right atrium 102 and the right ventricle 105 is open. Before the tricuspid valve 103 is opened, the right atrium 102 should be filled with oxygenated blood as much as possible to prepare for entry into the right ventricle 105. When the tricuspid valve 103 is opened, the oxygenated blood that has been stored in the right atrium 102 can flow into the right ventricle 105 in a large amount and fill it up. With this arrangement, the right ventricle 105 can be perfused with the maximum amount of oxygenated blood, and upon subsequent contraction of the heart, oxygenated blood is ejected into the pulmonary artery 109 and lungs to complete the pulmonary circulation.

2. During the late systole of the mitral valve 103 before opening and the next diastolic opening of the tricuspid valve 103, the balloon 207 and the balloon 208 are inflated to prevent the veins returning from the superior vena cava and the inferior vena cava 104, respectively. Blood is returned to prevent hypoxemia from entering the right atrium 102, while the brake perfusion catheter 206 perfuse oxygenated blood into the space of the right atrium 102.

3. The perfusion occlusion device 205 of the perfusion catheter assembly 21 is opened to allow oxygenated blood from the ECMO outflow end to enter the right atrium 102. Since blood flow and mixing take time, the oxygenated blood can be "irrigated" to the right atrium 102 a little earlier before the tricuspid valve 103 is opened. During this brief lavage, both balloons 207 and 208 are inflated and both occluders 205, 210 are open. Therefore, the blood stored in the right atrium 102 and the oxygenated blood previously stored in the perfusion end reservoir 203 during systole are mixed and forcibly discharged, so that the oxygenated blood can be largely filled into the right atrium 102. And ready to enter the right ventricle 105.

4. The occluder 210 on the drainage catheter 209 is closed to prevent oxygenation in the right atrium 102 from being drawn into the inflow path of the ECMO. The occluder 210 at the drain end of the ECMO begins to close after the right lavage 102 completes the "irrigation" procedure and remains closed during most of the diastolic phase, thus further reducing the recirculation of oxygenated blood back into the ECMO circuit. .

5. When the drainage end occluder 210 is closed, the drainage end reservoir 212, which has been passively filled with hypoxic blood or mixed blood during the last systole, supplies the stored blood to the ECMO circuit to maintain the ECMO. The blood pump can run continuously and stably.

Systolic phase:

1. During systole, the tricuspid valve 103 between the right atrium 102 and the right ventricle 105 is closed. During this period, venous return should be maximally inhaled into the ECMO drainage circuit and then pushed through the oxygenator through the blood pump to produce oxygenated blood. Since the venous return blood is obstructed by the previous end diastolic phase and the preload (Preload, pressure) of the inferior vena cava is increased, this preload accelerates the flow of the blood pump, thereby enhancing the suction of the inferior vena cava and, in the next An initial period of diastole helps oxygenated blood flow into the right atrium 102.

2. When the heart contracts, the balloons 208, 207 of the two catheter assemblies 21, 22 are deflated and contracted, thus creating a low-pressure pumping force that facilitates venous return of blood from the superior vena cava and superior vena cava 104. And fill the right atrium 105.

3. The occluder 205 of the perfusion catheter assembly 21 is closed to prevent oxygenated blood from the ECMO from entering the right atrium 102. During this time when the ECMO perfusion is blocked, the oxygenated blood of the ECMO will be shunted into the reservoir 203 at the perfusion end. As the blood volume in the reservoir increases, the pressure in the reservoir 203 will increase to establish a pressure gradient relative to the perfusion catheter, which will help when the next diastolic occlusion device 205 is opened. The blood stored in the blood reservoir 203 is discharged.

4. The occluder 210 of the drainage catheter assembly 22 is opened to receive venous return blood collected in the right atrium 102. With the help of the operation of the blood pump 202, the blood drawn into the drainage conduit 209 will be pushed through the oxygenator 201 to produce oxygenated blood. At the same time, the blood reservoir 212 of the drainage catheter assembly 22 can be re-expanded during this systole and filled with additional hypoxemia, and then in the next diastole, when the occluder 210 of the drainage end is closed, the stored blood is expelled to maintain Stable ECMO flow.

5. In order to maintain continuous operation of the blood pump 202, when the perfusion end occluder 205 is closed during systole, the oxygenated blood delivered by the ECMO will be pushed into the blood reservoir 203 in the perfusion catheter assembly 21 for storage and gradually ascending. high pressure. The high pressure blood stored in the perfusion end blood reservoir 203 will be expelled in a pressurized manner during the next diastolic phase when the perfusion end occluder 205 is opened.

The present invention includes six flow regulators distributed over the drainage conduit assembly 22 and the perfusion catheter assembly 21, and a VV ECMO control system that uses an electrocardiographic signal as a control reference, designed to reduce recirculation rates while maintaining The blood pump operates continuously and continuously. For example, the flow regulator can include two balloons 207, 208, two occluders 205, 210, and two blood reservoirs 203, 212. The purpose of the balloons 207, 208 is to regulate the amount of venous return blood of the human body, and the occluders 210, 205 are respectively used to prevent blood in the ECMO catheter from flowing through the drainage end and the perfusion end. The blood reservoirs 212, 203 are placed before the blood pump 202 and after the oxygenator 201, respectively. The manner in which the memories 212, 203 are controlled may be active or passive depending on the flow setting requirements to maintain continuous flow of the ECMO blood pump. The balloons 207, 208 are placed in the superior vena cava or inferior vena cava 104, so they are in contact with the blood, and should be designed in a configuration suitable for hemodynamics to avoid blood flow stagnation (Hemostasis). )Area. The occluders 205, 210 can be mounted inside or outside of the catheters 206, 209, and generally prefer an occluder design that is external to the body and that does not come into contact with blood. The present invention entails developing a control logic design that uses an electrocardiographic signal as an open loop controller for controlling reference signals. In theory, the current active control flow regulation system is a single-input multi-output controller, and the control objective is to reduce the recirculation rate of the VV ECMO system. In actual design implementation, the aforementioned six actuators (flow regulators) may all be selected, partially selected, or combined in different ways. For each flow regulator to be braked relative to those points in the ECG signal, it must be adjusted. In general, all control parameters for the selected flow regulator must be optimized simultaneously to achieve a design goal that minimizes the recirculation rate.

Figure 3A is a block diagram of the control flow of the present invention. The heart rhythm (usually the ECG waveform) can be continuously acquired by the data acquisition system and the signal is amplified by an algorithm to detect the time point at which the heart begins to contract (ie, the R wave). Figure 3B schematically depicts the triggering time point (brake or no braking) of each flow regulator brake. The steep rise and fall of the wave above the time series shown in Figure 3B represent the braking and closing of the regulator, respectively. The timing of braking or shutting down each flow regulator is relative to the R wave as the trigger timing. The magnitude of the time delay relative to the R wave is a predetermined control input parameter. There can be up to 12 control variables in this active control system, but depending on the selection of the balloon, occluder and blood reservoir on the ECMO system drainage and perfusion catheter assembly, the control combination can be determined accordingly. The control variables for brake and closing are all used or only partially used. The design can be carried out using a bionic cycle test bench or an animal experiment to perform the recirculation measurement. After repeated experiments to find the optimal control time point for reducing the recirculation rate as a control input parameter, in the present VV ECMO invention Realized.

In one embodiment of the invention, the extracorporeal flow regulator system includes a pneumatic pump, a sensing system that can receive a heart rhythm signal, and a controller that can generate control commands based on the set control logic and the sensed heart rate signal. The control logic is optimized to allow the diastolic phase to perfuse the maximum amount of oxygenated blood into the right ventricle and to draw the maximum amount of venous return hypoxic blood into the ECMO circuit during systole.

Example I: Drainage catheter equipped with a balloon

4A and 4B are side views of a drainage catheter assembly in accordance with an embodiment 1 of the present invention. 4A is a 1:1 scale drawing of the drainage catheter assembly, and FIG. 4B is an enlarged view of FIG. 4A. Figure 1A, Example I, depicts the balloon and drainage side holes of the device on the drainage catheter assembly. 5A and 5B are longitudinal cross-sectional views of a drainage catheter assembly in accordance with an embodiment 1 of the present invention. Figure 5C is a cross-sectional view of the drainage catheter assembly in accordance with Example I, showing the lumen assigned to the smaller lumen of the control air passage and assigned to the larger lumen. Fig. 6 is a longitudinal cross-sectional view of the balloon of the drainage catheter of the embodiment I of the present invention, showing a balloon, an air hole, a blood drainage side hole, and a development mark which the radiation cannot penetrate. Similar components that appear in different views use similar annotations throughout the description.

The drainage catheter assembly 30 generally includes two fluid passages, one fluid passage capable of transferring or withdrawing blood, and the other fluid passage connected to the drain end balloon 311 to drive the suction end balloon 311 to expand or contract, for example, the two fluid passages may be The drainage duct 301 and the drain end air duct 310 are provided. The drainage catheter 301 forms a first lumen, and the drainage air conduit 310 forms a second lumen, for example, a drainage air conduit 310 can be disposed within the drainage conduit 301. In at least one embodiment, both the drainage sleeve 301 and the drain air conduit 310 in the drainage catheter assembly 30 will have a portion of the side walls that merge into a common side wall and separate the lumens of the two by a septum. The lower end (or proximal end) of the drainage catheter 301 can be conveniently connected to the ECMO tube using, for example, a barbed quick connector. The upper end (or distal end) of the other side of the drainage sleeve 301 terminates in a sealed catheter end 316. The drainage catheter 301 mounts a drainage end balloon 311 on the side wall of the tapered extension 317 near the sealed catheter end 316. Gas communication of the balloon 312 with its designated extracorporeal controller is accomplished through the drainage end air conduit 310 and further through the side aperture 313 drilled through the tapered extension 317. The drain end air conduit 310 is spaced apart from the drain conduit assembly 30 at a location remote from the sealed conduit end 316, such as a drain conduit 301 and a drain end air conduit 310 disposed at one end of the drain conduit assembly 30 having the sealed conduit end 316. The drain end balloon 311 and the side holes 303 are disposed to be distributed at the tip end region of the drainage catheter assembly 30. For the drain end air duct 310, the side holes 313 are disposed inside the drain end balloon 311 and near the seal tube end 316. The separation joint of the drainage end air conduit 310 may be separated from the skin incision location of the drainage catheter assembly 30 through the exterior of the patient's body by an appropriate distance. In the present embodiment, the merged transition zone is reinforced and protected by the furcation structure of the draft conduit assembly 30 having a greater wall thickness.

A plurality of openings or drainage holes 303 are disposed along the length of the drainage conduit 301. The drainage holes 303 are distributed over the section below the balloon 311. The array of drainage holes 303 is preferably arranged in a staggered manner so as to maximize the inhalation of venous return blood. The conduit wall 302 between the array of drain holes and the separation transition zone is reinforced with a polymer or wire. Since the catheter tip 316 is sealed, the drainage aperture 303 on the side wall of the drainage sleeve 301 should have a smooth internal inflow ramp 304 to seal the catheter tip 305 to avoid localized blood flow lag areas around the drainage aperture 303.

As shown in FIG. 6, the drainage end balloon 311 is mounted on the exterior of the tapered extension 317 that is coupled to the sealed conduit end 316 of the drainage catheter assembly 30. The indicators 314, 315 on both sides of the drainage end balloon 311 are connected to the drainage catheter 301, are made of a material that the radiation cannot penetrate, and are combined or embedded with the drainage catheter 301. The balloon can be made using a polymeric material such as, but not limited to, silicone or polyurethane. The balloon volume 312 is about 3 to 15 milliliters, depending on the size of the blood vessel to be inserted and the balloon occlusion ratio to be achieved when the balloon 311 is inflated to prevent venous return. Pneumatic communication of the balloon 311 with the designated controller is accomplished via an air conduit 310 with one end terminating in the flow regulator and the other end coupled to the tapered extension 317 and causing decompression or compressed air to move back and forth depending on control commands The balloon 311 is deflated or inflated.

Blood is drained from a drainage catheter 301 placed in the superior vena cava or inferior vena cava. Figure 7 is a schematic illustration of the relative insertion position of the current drainage sleeve placed at the junction of the inferior vena cava 104 and the right atrium 102.

This embodiment is a conversion application of the working principle shown in Figures 1 and 2. It should be noted that in Figures 1 and 2, blood enters the ECMO circuit only via the distal end of the balloon 311, and the blood reservoir 212 needs to be actuated in conjunction with the occluder 210 to regulate flow within the ECMO circuit. In the present embodiment, the catheter has a sealed catheter end 316 and an array of drainage holes 303 distributed in the vicinity of the balloon 311, and the blood reservoirs 212, 203 may be omitted or the occlusion devices 210, 205 may be omitted or both omitted to simplify Hardware setup and control logic design.

The sealed catheter tip 316 helps prevent oxygenated blood or mixed blood from being drawn into the ECMO circuit when the tip end balloon 311 expands to prevent oxygenated or mixed blood flowing from the right atrium 102, thereby reducing undesirable Recycling that occurs. Although the drainage end balloon 311 is inflated, the hypoxic blood in the diastolic venous return can still be continuously drawn from the plurality of drainage holes 303. Therefore, there is no time to interrupt the infusion of venous return blood, and the operation of the blood reservoir is eliminated to maintain the continuous operation of the uninterrupted ECMO blood pump. In fact, controlling the catheter to block flow and regulate venous return in this embodiment is controlled by a mechanism that is fused into a sealed balloon. When the drainage end balloon 311 is inflated, the venous return blood of the superior vena cava or the inferior vena cava is drained through the drainage hole 303 according to the position at which the drainage catheter 209 is placed. When the drainage end balloon 311 is contracted, the venous return of the superior vena cava and the inferior vena cava can be withdrawn into the drainage catheter 209. The drainage end balloon 311 can also act as a flow choke to prevent recirculation of flow in the right atrium. With the expansion of the drainage end balloon 311, the local high pressure caused by the flow deceleration and clogging caused by the obstruction of the drainage end balloon 311 will divert the oxygenated blood flow into the tricuspid valve 103, if the balloon expansion time is assumed. The point is appropriately controlled in conjunction with the relaxation of the right ventricular muscle and the opening of the tricuspid valve. This change in flow direction can cause the right ventricle to infuse the maximum amount of oxygenated blood, and jointly generate the driving force for pushing and pulling of the right ventricle to receive from the right. Atrial accelerated perfusion flow.

A commercially available single chamber perfusion catheter (without moving parts or flow regulators) can be used with current drainage catheter embodiments to form a VV ECMO circuit with low recirculation rate. In fact, this assembly is the simplest active control VV ECMO device.

Example II: Drainage catheter with non-tightly coupled balloon

8A and 8B are side views of a drainage catheter assembly in accordance with an embodiment II of the present invention to illustrate the relationship between a balloon catheter and an inserted single chamber drainage catheter. Figure 8A is a 1:1 scale drawing of the drainage catheter assembly and Figure 8B is an enlarged view of Figure 8A. The drainage catheter assembly 40 includes a drainage conduit 401, a drain end air conduit 414, and a drain end Y-joint 430. Figures 9A and 9B are longitudinal cross-sectional views of a drainage catheter assembly in accordance with an embodiment II of the present invention showing the internal relationship when the drainage conduit assembly is inserted into the drainage end air conduit. Figure 9A is a 1:1 scale drawing of the drainage catheter assembly and Figure 9B is an enlarged view of Figure 9A. The drainage catheter 401 is coupled to the air conduit 414 and the Y-joint 430, and it is shown in Figures 9A and 9B that the active control flow occlusion device that provides for venous return blood is achieved using the balloon 415 and the air conduit 414. Figure 10 is a longitudinal cross-sectional view of the balloon of the drainage catheter of Example II, showing the balloon, the airflow hole, the blood drainage side hole, and the insufficiency of the radiation. Figure 11 is a longitudinal cross-sectional view of the Y-joint of the drainage catheter of Example II showing the passage of the air conduit insertion provided by the Y-joint and the design of the control of the blood flow stagnation zone. The configuration of the detailed Y-joint 430 in Figures 11, 12A and 12B includes an adapter that provides for the insertion of an air conduit so that there is no blood leakage and air ingress when the air conduit is delivered into the drainage catheter.

The drainage catheter assembly 40 is a thin walled tube made of a biocompatible polymeric material such as, but not limited to, polyurethane or silicone. In the present embodiment, the catheter tip 416 is open and a plurality of drainage holes 403 are drilled along the wall of the drainage catheter 401 proximate the catheter tip opening 416. These drainage holes 403 are designed to draw a maximum amount of venous return blood regardless of whether the balloon 415 is inflated or contracted. In order to achieve less trauma during surgical insertion, the catheter is thin-walled and the embedding-strengthening unit 404 is added to allow the catheter to be inserted smoothly and without bending. The lower half of the drainage conduit assembly 40 is progressively enlarged to reduce flow resistance and provide a structural transition to interface with the Y-joint 430.

9A and 9B depict the insertion of an air conduit into the drainage catheter assembly 40. The air conduit 414 is generally straight prior to insertion of the drainage conduit, but the bendable nature of the air conduit 414 allows the air conduit 414 to flex along the inserted path. The air duct 414 may generally include an inner tube 411 (sensing pressure) and an outer tube 412 (transporting air), and the inner tube 411 is longitudinally disposed within the outer tube 412. Around the upper end of the air duct 414 is a balloon 415 made of a polymer such as polyurethane or silicone. The balloon 415 can be controlled to expand or contract by an external actuator system. 8A, 8B, 9A, 9B, and 10 show a fully inflated balloon 415 having a shape that conforms to the shape of the dip-shaped axial shape or the shape of the blow molded mold. The balloon 415 is seamlessly coupled or attached to the air conduit 414. Figure 10 shows a preferred balloon engagement mode in which the distal end of the tubular balloon is seamlessly bonded to the inner tube 411 and the proximal end of the tubular balloon is seamlessly bonded to the outer tube 412. Inner tube 411 typically has an outer diameter dimension of approximately 1 mm. Physiological saline can be injected to fill the inner tube cavity 424 to form a water pressure sensing channel and extend to the tip opening 423 to facilitate measurement of vena cava blood pressure during ECMO operation. Gas communication between the balloon 417 and the extracorporeal controller is achieved via the lumen space between the inner tube 411 and the outer tube 412. To assist in placing the balloon 415 in place during insertion, a marker that the radiation cannot penetrate is disposed at the proximal end 422 and the distal end 421 of the balloon 415. The catheter tip 416 is contoured at the distal end of the inner tube 411 with a liner to provide a smooth profile to protect the blood vessel from damage when the catheter is pushed.

As shown in FIGS. 12A and 12B, the Y-joint 430 generally includes a Y-shaped body 431, a Y-slit hemostatic cone 433, a stopper 432, and a locking cover 434. The two sides of the main arm of the Y-joint 430 are butted together with the drainage catheter 401 and the ECMO tube 402, respectively, to form a drainage channel for withdrawing venous return blood of the inferior vena cava or superior vena cava. The plug 432 is disposed in the side arm of the Y-joint 430 for use with the Y-slot cone 433 to form a sealing mechanism when the air conduit 414 is pushed and installed. Plug 432 and Y-slot cone 433 are typically made of an elastically deformable polymer such as silicone or rubber. One side of the plug 432 is flatly mounted on the inner wall of the drainage catheter. Typically, the surface of the plug that enters the drainage conduit 401 with the air conduit 414 and contacts the blood requires a smooth, continuous flow interface that minimizes the likelihood of a blood clot forming at the surface discontinuities around the drainage conduit and the air conduit interface. A Y-slot cone is accommodated at the other end of the plug 432 as a hemostatic valve.

To install the air duct 414, the air duct 414 is first inserted through the Y-slot cone 433 and then the air duct 414 is pushed through the channel wall of the plug 432. The outer wall of the air duct 414 and the passage of the plug 432 should be designed with a suitable gap so that it can be kept smooth and does not leak during the advancement of the air duct. As shown in FIG. 11, the locking cover 434 is coupled to the Y-joint main body 431 through a thread, and the pressing force of the locking cover 434 applied to the Y-slot cone 433 hemostatic valve is controlled by the number of turns of the rotating screw. To provide different degrees of sealing. When the air duct 414 is inserted, the locking cover 434 is first released to loosen the engagement between the air duct 414 and the balloon 415 and the plug, and then the locking cover is locked to compress the Y-slot cone 433 to prevent the drainage duct and the air duct from being drained. The blood flowing back between the edges of the interface to achieve the purpose of stopping bleeding. When the ECMO blood pump is running, a negative pressure gradient is generated along the catheter to draw blood, so the blood pressure around the Y-joint 430 is typically lower than atmospheric pressure, so the Y-slot cone 433 hemostasis valve must provide a tight seal to prevent The outside air is drawn into the bloodstream. A tight seal failure can result in a life-threatening air embolism.

In the practical application of this embodiment II, the intubation process is completed in two steps. The first step is to implant the drainage catheter 401 using a tool set of needles, guidewires, and introducers. This procedure is identical to the practice of a single surgeon in a clinically performed single-chamber catheter that is inserted into the ECMO system from the superior vena cava or inferior vena cava. The second step is to introduce an air duct 414. The balloon 415 on the air conduit 414 first deflates into a smaller profile ready to be inserted through the entrance of the hemostasis valve of the Y-slot cone 433. The locking cover 434 is first released to receive the air conduit 414, then advanced along the drainage catheter 401 after the air conduit 414 has passed through the plug 432, and finally the balloon 415 is properly placed outside the catheter tip opening 416 to the desired position. tight. The imaging system can be used for precise guidance to complete the placement of steps 1 and 2. Figure 13 shows the insertion and placement of this Example II at the junction of the inferior vena cava and the right atrium.

Example III: Perfusion catheter fitted with an occluder

The perfusion catheter assembly 50 of this embodiment III is illustrated in Figures 14A and 14B. Figure 14A is a 1:1 scale view of the perfusion catheter assembly and Figure 14B is an enlarged view of Figure 14A. 15A and 15B are cross-sectional views of the perfusion catheter assembly of Example III showing details of the relationship between the occluder, the blood reservoir, and the combination of the perfusion catheter and the ECMO tube. Figure 15A is a 1:1 scale drawing of the perfusion catheter assembly, and Figure 15B is an enlarged view of Figure 15A. The perfusion cannula assembly 50 includes a perfusion catheter 501, an occluder module 520, a gas line 524, and an ECMO tube 511, wherein the occluder modules 520 are connected in series between the perfusion conduit 501 and the ECMO tube 511, respectively. The occluder module 520 includes an occluder 525 disposed in the occluder chamber 523 and the blood reservoir 522. In one embodiment of the invention, the occluder 525 is coupled to the perfusion catheter 501 and the blood reservoir 522 is coupled to the ECMO tube 511. The perfusion cannula 501 is a conventional single chamber catheter, as disclosed in Example II. The occluder (perfusion occlusion) 525, 205, 210 and (perfusion) blood reservoirs 522, 202, 212 are arranged in series to reduce flow resistance, wherein the regulation of the perfusion flow can be via compression or expansion of the occluder (perfusion occluder) 525, 205, 210 cross-sectional size, or with the passive blood reservoirs 522, 203, 212 with the action of the occluder (perfusion occlusion) 525, 205, 210 to achieve volume control, and maintain the continuity of the blood pump in the life support system Running. Tip opening 504 and side opening 503 on the perfusion catheter are used to provide perfusion of blood. For example, the tip opening 504 is disposed at one end of the perfusion tube 501, and the side hole 503 is disposed on the side wall of the perfusion tube 501. The occluder 525 currently designed to block blood flow in the perfusion catheter 501 is a flexible catheter having a distributed wall thickness. When the catheter is compressed by air, the perfusion occlusion device 525 contained in the occluder chamber 523 will be squeezed to reduce the cross-sectional area to prevent or slow the flow of perfused blood while the perfusion reservoir 522 will follow the reaction. The expansion is to receive the blocked flow so that the flow in the ECMO loop can run continuously. In fact, the manner in which the present embodiment incorporates the occluder and blood reservoir functions has been shown and described in Figures 1 and 2. The reservoir volume is passively reacted with active occlusion flow control provided by the extracorporeal flow regulation system.

Figures 16 and 17 show the detailed structure of the occluder module. Figure 16 depicts an occluder and blood reservoir operation during diastole, with the occluder in a fully open state and the plenum maintained in an unexpanded stretched state. Figure 17 depicts an occlusion device and a blood reservoir operation during systole, where the occluder is in a fully closed state while the blood reservoir is elastically expanded to receive the flow of the ECMO circuit. Current occlusion plug sub-systems typically include a barbed adapter 521, an occluder module 525, a gas chamber 527, and a gas line 524 that is coupled to the gas chamber 527 at the barbed adapter 526. The occluder module 525 is controlled in pneumatic communication with a flow regulating system external to the body. The ECMO tube 511 is connected to the occluder module 520 via a barbed adapter 521. The occluder 525 of the occluder module 520 is sealingly coupled to both ends of the gas chamber 527. The gas chamber structure is rigid or semi-rigid with respect to the flexible conduit so that the cross-sectional area of the occluder 525 can be controlled as the pressure of the gas chamber is adjusted. The perfusion cannula 501 is quickly coupled to the distal end 523 of the occluder using a barbed adapter.

The extracorporeal life support system of the above embodiment of the present invention may include only one balloon 207, 208, 311, 415, an occluder (module) 205, 210, 525 or a blood reservoir 203, 212, 522. The balloons 207, 208, 311, 415, or have occluders (modules) 205, 210, 525 or have blood reservoirs 203, 212, 522 or both, which can be actuated according to the patient's heart rhythm, This allows the most oxygenated blood to enter the right ventricle during diastole and the most venous return of hypoxic blood is drawn into the life-supporting circuit during systole.

The present invention may be embodied in other specific forms without departing from the basic principles of the teachings disclosed and described herein. The embodiments described herein are considered in all respects as illustrative and not restrictive. All changes that have the same meaning and scope as the claims are included in their scope.

21‧‧‧Perfusion catheter set

23‧‧‧Drainage catheter set

30‧‧‧Draining catheter set

40‧‧‧Draining catheter set

50‧‧‧perfusion catheter set

101‧‧‧ superior vena cava

102‧‧‧ right atrium

103‧‧‧tricuspid valve

104‧‧‧Inferior vena cava

105‧‧‧ right ventricle

109‧‧‧Pulmonary artery

201‧‧‧Oxygenator

202‧‧‧ blood pump

203‧‧‧Port-end blood reservoir

205‧‧‧Sipper obstruction

206‧‧‧Porting catheter

207‧‧‧perfusion balloon

208‧‧‧Drainage balloon

209‧‧‧Draining balloon

210‧‧‧Drainage occluder

211‧‧‧ECMO drainage catheter

212‧‧‧Drainage end blood reservoir

301‧‧‧Drainage catheter

302‧‧‧Enhanced drainage tube wall

303‧‧‧drain

304‧‧‧Inflow slope

305‧‧‧ Sealed catheter end

310‧‧‧Air duct

311‧‧‧ balloon

312‧‧‧ Balloon

313‧‧‧ side hole

314‧‧‧Insert that the radiation cannot penetrate

315‧‧‧Insert that the radiation cannot penetrate

316‧‧‧Sealed catheter end

317‧‧‧Cone extension

401‧‧‧Drainage catheter

402‧‧‧ECMO tube

403‧‧‧drain

404‧‧‧Enhanced drainage tube wall

411‧‧‧Inside

412‧‧‧External management

414‧‧‧Air duct

415‧‧‧ balloon

416‧‧‧ catheter end

417‧‧‧ balloon

418‧‧‧Adhesive

421‧‧‧Insert that the radiation cannot penetrate

422‧‧‧Intensity impervious to radiation

423‧‧‧Top opening

424‧‧‧ inner tube cavity

430‧‧‧Y type connector

431‧‧‧Y-joint body

432‧‧‧plug

433‧‧‧Y slit cone

434‧‧‧Lock cover

501‧‧‧Porting catheter

503‧‧‧ side hole

504‧‧‧ tip opening

511‧‧‧ECMO tube

520‧‧‧Blocker module

521‧‧‧Adapter

522‧‧ ‧ blood reservoir

523‧‧‧Blocker chamber

524‧‧‧ gas pipeline

525‧‧‧Blocker

526‧‧‧Adapter

527‧‧‧ gas chamber

BRIEF DESCRIPTION OF THE DRAWINGS A brief description of the present invention can be more specifically described by the embodiments shown in the drawings. The drawings depict only typical embodiments of the invention, but are not to be construed as limiting The embodiments and best modes mentioned in the present invention will now be described using the drawings, in which:

Figure 1 is a schematic diagram depicting a VV ECMO loop and pulmonary circulation. The figure shows the control action characteristics of each of the six flow regulators when the diastolic tricuspid valve is open.

Figure 2 is a schematic diagram depicting the VV ECMO loop and pulmonary circulation. The figure shows the control action characteristics of each of the six flow regulators when the systolic tricuspid valve is closed.

Figure 3A is a block diagram of the control flow of the present invention.

Figure 3B depicts the point in time (brake or no braking) triggered with each flow regulator.

4A and 4B are side views of a drainage catheter assembly in accordance with an embodiment 1 of the present invention.

5A and 5B are longitudinal cross-sectional views of a drainage catheter assembly in accordance with an embodiment 1 of the present invention.

5C is a cross-sectional view of a drainage catheter assembly in accordance with Example 1.

Figure 6 is a longitudinal cross-sectional view of a drainage catheter balloon in accordance with an embodiment I of the present invention.

Figure 7 is a schematic illustration of the placement of the drainage catheter of Example I placed at the junction of the inferior vena cava and the right atrium.

8A and 8B are side views of a drainage catheter assembly in accordance with an embodiment II of the present invention.

9A and 9B are longitudinal cross-sectional views of a drainage catheter assembly in accordance with an embodiment II of the present invention.

Figure 10 is a longitudinal cross-sectional view of a drainage catheter balloon in accordance with Example II of the present invention.

Figure 11 is a longitudinal cross-sectional view of a drainage Y-joint of a drainage catheter according to Embodiment 1 of the present invention.

Figure 12A is a detailed illustration of a drainage Y-joint of a drainage catheter in accordance with an embodiment II of the present invention.

Figure 12B is an exploded view of the drainage Y-joint of the drainage catheter in accordance with an embodiment II of the present invention.

Figure 13 is a schematic illustration of the position of the drainage catheter of Example II placed at the junction of the inferior vena cava and the right atrium.

14A and 14B are side views of a perfusion catheter assembly in accordance with an embodiment III of the present invention.

15A and 15B are cross-sectional views of a perfusion catheter assembly in accordance with an embodiment III of the present invention.

16 and 17 are cross-sectional views of a perfusion catheter occluder in accordance with an embodiment III of the present invention.

Claims (10)

An extracorporeal life support system comprising: a blood pump and an oxygenator disposed outside a patient's body; a drainage catheter assembly disposed in the superior vena cava or inferior vena cava for receiving hypoxic blood, including a patient's heart rhythm At least one element of the movable drainage balloon, the drainage end occluder and the drainage end blood reservoir, wherein the drainage end balloon expands or contracts to control venous return blood, and the drainage end occluder is compressed or relaxed to control inhalation Blood flow in the life support system, the drain reservoir is actuated together with the drain occluder to maintain continuous blood pump flow; and the perfusion catheter assembly is disposed relative to the drainage catheter assembly and is disposed in the superior vena cava or under In the vena cava, the perfusion catheter assembly is used to circulate oxygenated blood back into the patient's bloodstream. The extracorporeal life support system of claim 1, wherein the drainage catheter assembly comprises two fluid channels, one fluid channel is capable of transmitting blood, and the other fluid channel is coupled to the drainage end balloon to drive the balloon inflation of the drainage end. Or deflation, the two fluid passages are separated and not in fluid communication with each other. The extracorporeal life support system of claim 2, wherein the drainage catheter assembly comprises a sealed catheter tip disposed on one end of the drainage catheter assembly, and a plurality of disposed on the side wall of the drainage catheter assembly and adjacent the end of the drainage catheter Drainage hole. The extracorporeal life support system of claim 1, wherein the drainage catheter assembly comprises a drainage catheter, a drainage end air conduit, and a drain end Y-joint, and the drainage end air conduit is coupled to the drainage end balloon and is drained The catheter is completely separated, wherein the drainage catheter comprises a catheter tip and a plurality of drainage holes distributed at one end of the catheter, the drainage catheter is connected to the main arm of the Y-joint of the drainage end, and a plug is mounted on the side arm of the Y-joint for The drainage catheter is inserted. The in vitro life support system according to claim 4, wherein the drainage end air conduit comprises an inner tube and an outer tube, the outer tube is used for pneumatically controlling the expansion or contraction of the balloon at the drainage end, and the inner tube is filled with the liquid for blood pressure measurement. . The in vitro life support system of claim 1, wherein the patient's heart rhythm is obtained from an electrocardiogram. An extracorporeal life support system comprising: a blood pump and an oxygenator disposed outside a patient's body; a perfusion catheter assembly disposed in the superior vena cava or inferior vena cava for perfusion of oxygenated blood, including actuation according to a patient's heart rhythm At least one component of the perfusion end balloon, the perfusion end occluder, and the perfusion end blood reservoir, wherein the perfusion end balloon expands or contracts to control venous return blood, and the perfusion end occluder is compressed or relaxed to control perfusion to the patient Blood flow to the right atrium, the perfusion end of the blood reservoir is actuated with the perfusion end occluder to maintain continuous blood pump flow; and the drainage catheter assembly relative to the perfusion catheter assembly is placed in the superior vena cava or inferior vena cava The drainage catheter assembly is configured to receive hypoxic blood from venous return. The in vitro life support system of claim 7, wherein the perfusion catheter assembly comprises a single chamber catheter, a perfusion end occluder, and a perfusion end blood reservoir, and the series arrangement minimizes flow resistance, wherein the perfusion flow is via The cross-sectional area of the perfusion end occluder is compressed or expanded and combined with the passive perfusion end blood reservoir to regulate the movement of the perfusion end occluder to maintain the operation of the blood pump in the life support system. The in vitro life support system of claim 7, wherein the patient's heart rhythm is obtained from an electrocardiogram. An extracorporeal life support system comprising: a blood pump and an oxygenator disposed outside a patient's body; a drainage catheter assembly disposed in the superior vena cava or inferior vena cava for receiving hypoxic blood, including a patient's heart rhythm At least one element of the movable drainage balloon, the drainage end occluder and the drainage end blood reservoir, wherein the drainage end balloon expands or contracts to control venous return blood, and the drainage end occluder is compressed or relaxed to control inhalation Blood flow in the life support system, the drain reservoir is actuated together with the drain occluder to maintain continuous blood pump flow; and the perfusion catheter assembly is disposed relative to the drainage catheter assembly and is disposed in the superior vena cava or under In the vena cava to perfuse hyperoxic blood from a life support system comprising at least one element in the perfusion end balloon, the perfusion end occluder and the perfusion end blood reservoir actuated according to the patient's heart rhythm, wherein the perfusion end The balloon expands or contracts to control venous return blood, and the perfusion end occluder is compressed or relaxed to control blood flow that is infused into the patient's right atrium. The flow end reservoir is actuated with the perfusion end occluder to maintain a continuous blood pump flow; and the drainage and perfusion catheter assembly operates in an optimal manner to enable perfusion of the maximum amount of hyperoxia during diastole The blood enters the right ventricle and reduces the hyperoxic blood that is recycled back to the life support circuit during systole.