JP2019157653A - Roller pump and control method thereof - Google Patents

Abstract

To attain a roller pump capable of coping with change of pressure in a state of driving the roller pump, even in a case where the pressure exceeds a fixed range.SOLUTION: A roller pump 10 comprises: a pump sleeve 70 to which a tube constituting a blood circuit can be attached; a rotor unit 20 rotatably supported to a first shaft inside the pump sleeve 70; a roller 40 provided in the rotor unit 20 so that a distance from the first shaft can be changed; a pump motor 50 configured to rotate the rotor unit 20; and a control unit 80 that adjusts the distance from the first shaft of the roller 40 when the pressure in a tube lumen deviates from a predetermined range.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a roller pump and a control method thereof.

  A roller pump is a pump that pumps out fluid by squeezing it with a roller that rotates a tube through which fluid can flow. Conventionally, in the medical field, especially in extracorporeal circulation circuits such as heart-lung machines and artificial dialysis, cost and ease of handling are high. It is used as a blood pump for blood removal and blood removal.

  When using a roller pump, it is necessary to sandwich a tube between the pump sleeve and the roller and tighten it to a certain extent. Particularly in the field of cardiopulmonary bypass, it is necessary to perform so-called occlusion adjustment that sets an appropriate degree of tightening (closed degree) before using the roller pump. Specific methods for adjusting occlusion include methods using infusion sets described in the well-known “Standard connection method for cardiopulmonary bypass devices and corresponding safety education guidelines”, etc. And a method of measuring the rate of pressure drop.

  Occlusion adjustment is performed manually by medical personnel. For example, an occlusion adjustment knob provided on the roller and a lock mechanism thereof are integrally provided so that the occlusion adjustment and the lock can be performed by a series of operations (see, for example, Patent Document 1). .

  By the way, in the extracorporeal circuit, a part of the extracorporeal circuit may be blocked during the operation due to bending or bending of the blood tube or inappropriate forceps operation. In particular, when the blood circuit is blocked on the downstream side of the roller pump while the roller pump is being driven, an excessive amount of blood is sent into the circuit, and the pressure in the circuit rapidly increases. As a result, the connection between the blood tube and each device may be released, or the artificial lung or the hollow fiber of the dialyzer may be broken (exploded).

  In addition, the blood removal cannula that removes blood from the human body (inside the surgical field) to the extracorporeal circuit and the blood removal cannula of the suction blood cannula that draws blood from the surgical field stick to body tissues such as blood vessel walls by negative pressure. May be blocked. When the blood circuit is blocked upstream of such a roller pump, if the roller pump continues to be driven, the blood in the circuit is delivered even though there is little or no blood flowing into the extracorporeal circuit. Continue to be. As a result, the negative pressure in the circuit increases, and the blood removal hole of the suction cannula may stick to the tissue in the body more strongly and damage the tissue, or hemolysis may occur due to the negative pressure in the circuit. .

  From the above situation, the roller pump is set to automatically stop driving when the pressure in the extracorporeal circulation circuit for blood supply exceeds a certain value. The medical staff needs to remove the blockage of the extracorporeal circuit and restart the roller pump after the roller pump stops driving. When the roller pump is stopped, extracorporeal circulation is interrupted even though it is temporary. Therefore, it is required to promptly restart the roller pump so as not to put a burden on the patient. However, when the roller pump is re-driven, various operations and readjustments are necessary, and re-driving of the roller pump requires a lot of labor and is difficult to restart in a short time.

  Furthermore, in surgery and dialysis, the patient's afterload may vary during the procedure. “Afterload” refers to the resistance applied when the pump delivers blood into the patient's body. The conventional roller pump completes the occlusion adjustment before driving, and it is difficult to adjust this during the operation. For this reason, even if the contraction of the peripheral blood vessels of the patient or the blood viscosity changes during the operation and the afterload increases, a steady flow of blood must be delivered at a constant rotational speed. Such a condition increases the pressure when blood is pumped out of the pump and places a heavy burden on the patient.

JP 2000-80988 A

  The subject of this indication is enabling it to realize a roller pump which can respond to change of pressure in the state where a roller pump was driven, even when pressure exceeded a certain range.

  Hereinafter, the aspect of this invention made | formed in order to solve such a subject is described. In addition, the component employ | adopted in each aspect as described below can be employ | adopted as arbitrary combinations as possible.

  One aspect of the roller pump of the present disclosure includes a pump sleeve to which a tube constituting a blood circuit can be attached, a rotor unit rotatably supported with respect to the first shaft inside the pump sleeve, and the first shaft The distance between the first shaft of the roller when the pressure in the tube lumen deviates from a predetermined range. And a control unit for adjustment.

  According to one aspect of the roller pump, it is possible to adjust the degree of closure based on the pressure in the tube lumen constituting the blood circuit. Therefore, even when the extracorporeal circuit is blocked and the pressure rises abnormally, it is possible to stop excessive blood delivery by eliminating the tightening of the tube by the roller, and unintentionally disconnect the tube from the device. And breakage of hollow fibers such as artificial lungs and dialyzers.

  In addition, in the conventional roller pump, since the degree of pressure closure was adjusted manually, it was necessary to stop the roller pump once when the extracorporeal circuit was closed and the pressure increased abnormally. However, the degree of closure is automatically adjusted and the roller pump is idle, preventing the disconnection between the tube and device and the breakage of hollow fibers such as artificial lungs and dialyzers without stopping the pump. Is possible. If the occlusion of the extracorporeal circuit is resolved, the pressure in the circuit decreases and an appropriate pressure closing degree is automatically adjusted. Since the pump continues to be driven during this time, the extracorporeal circulation can be resumed without a time lag from the adjustment of the pressure closing degree. Furthermore, since all the series of schemes can be performed automatically, the burden on medical staff can be reduced.

  In one aspect of the roller pump, the controller causes the roller to approach the first axis when the pressure in the tube lumen increases by 100 mmHg or more, and the pressure in the tube lumen causes the roller to approach the first axis. When the pressure is reduced by 50 mmHg or more from the pressure at the time, the roller can be separated from the first shaft.

  In this way, when the extracorporeal circuit is blocked and the pressure rises to a certain level or higher, the tube is released from the connection by releasing the tightening of the tube and hollow fibers such as artificial lungs and dialyzers. Can prevent damage. Further, when the blockage of the extracorporeal circuit is eliminated and the pressure in the extracorporeal circuit reaches an appropriate level, an appropriate pressure closure degree can be automatically set and the extracorporeal circulation can be resumed.

  In one aspect of the roller pump, the controller causes the roller to approach the first shaft when the tube lumen pressure drops by 50 mmHg or more, and the tube lumen pressure causes the roller to move away from the first shaft. When the pressure is increased by 50 mmHg or more from the pressure, the roller can be separated from the first shaft.

  In this way, when the extracorporeal circuit is blocked and the pressure drops to a certain level, hemolysis associated with abnormal pressure reduction or negative pressure generation in the extracorporeal circuit by eliminating the tightening of the tube. Can be suppressed. Further, when the blockage of the extracorporeal circuit is eliminated and the pressure in the extracorporeal circuit reaches an appropriate level, an appropriate pressure closure degree can be automatically set and the extracorporeal circulation can be resumed.

  One aspect of the roller pump includes at least two adjustment screws for moving the roller closer to or away from the first shaft, an adjustment motor for rotating the adjustment screw, and different diameters for transmitting force from the adjustment motor to the adjustment screw. An adjustment unit having a gear may be further provided.

  In this way, precise occlusion adjustment can be performed by torque generated by the difference in the number of gear teeth.

  In this case, at least two gears have a motor side gear attached to the adjustment motor and a screw side gear attached to the adjustment screw, and the motor side gear has a smaller diameter than the screw side gear. Can do.

  In this way, when the power is transmitted from the adjusting motor to the adjusting screw, the roller moving distance per one rotation of the motor becomes small, and more precise occlusion adjustment becomes possible. Further, since the torque transmitted to the adjusting screw is also increased, more reliable occlusion adjustment is possible.

  One aspect of the control method of the roller pump of the present disclosure includes a pump sleeve to which a tube constituting a blood circuit can be attached, a rotor unit rotatably supported with respect to the first shaft inside the pump sleeve, In a roller pump having a roller provided in a rotor unit so that the distance to the shaft of 1 can be changed and a pump motor for rotating the rotor unit, when the pressure in the tube lumen deviates from a predetermined range, the pump The step of changing the position of the roller is provided without stopping the motor.

  According to one aspect of the roller pump control method, it is possible to adjust the degree of closure based on the pressure in the tube lumen constituting the blood circuit. Therefore, even when the extracorporeal circuit is blocked and the pressure rises abnormally, it is possible to stop excessive blood delivery by eliminating the tightening of the tube by the roller, and unintentionally disconnect the tube from the device. And breakage of hollow fibers such as artificial lungs and dialyzers.

  In one aspect of the roller pump control method, the step of changing the position of the roller includes a first step of bringing the roller closer to the first axis when the pressure in the tube lumen is increased by 100 mmHg or more, and the first step And a second step of separating the roller from the first shaft when the pressure in the tube lumen drops by 50 mmHg or more from the pressure at the time of performing the first step.

  In this way, when the extracorporeal circuit is blocked and the pressure rises to a certain level or higher, the tube is released from the connection by releasing the tightening of the tube and hollow fibers such as artificial lungs and dialyzers. Can prevent damage. Further, when the blockage of the extracorporeal circuit is eliminated and the pressure in the extracorporeal circuit reaches an appropriate level, an appropriate pressure closure degree can be automatically set and the extracorporeal circulation can be resumed.

  In one aspect of the roller pump control method, the step of changing the position of the roller includes a first step of causing the roller to approach the first shaft when the pressure in the tube lumen is reduced by 50 mmHg or more, and the first step. And a second step of separating the roller from the first shaft when the pressure in the tube lumen increases by 50 mmHg or more from the pressure at the time of performing the first step.

  In this way, when the extracorporeal circuit is blocked and the pressure drops to a certain level, hemolysis associated with abnormal pressure reduction or negative pressure generation in the extracorporeal circuit by eliminating the tightening of the tube. Can be suppressed. Further, when the blockage of the extracorporeal circuit is eliminated and the pressure in the extracorporeal circuit reaches an appropriate level, an appropriate pressure closure degree can be automatically set and the extracorporeal circulation can be resumed.

  According to the roller pump of the present disclosure, it is possible to cope with a pressure change in the extracorporeal circuit while driving the roller pump.

It is a mimetic diagram showing a blood circuit to which a roller pump concerning one embodiment is applied. 1 is an overall view showing a roller pump according to an embodiment. It is sectional drawing in the II-II line of the roller pump shown in FIG. It is a perspective view which shows the rotor unit which concerns on one Embodiment. It is a perspective view showing each composition of a rotor unit concerning one embodiment. It is a back perspective view showing a rotor unit concerning one embodiment. It is a figure which shows the 1st state of the switching unit which concerns on this one embodiment. It is a figure which shows the 2nd state of the switching unit which concerns on one Embodiment.

  A roller pump according to an embodiment will be described with reference to the drawings. In addition, this embodiment is only one embodiment of this invention, and it cannot be overemphasized that an embodiment can be changed in the range which does not change the summary of this invention.

  FIG. 1 shows an example of a blood circuit incorporating a roller pump according to this embodiment. The extracorporeal circuit 1 can be applied to surgical operations such as the heart. The blood taken from the patient's body flows through the blood collection line 4 and is introduced into the reservoir 2. This blood is extracted from the reservoir 1 by the roller pump 10, oxygenated through the artificial lung 3, and then circulated through the blood supply line 5 and returned to the patient's body. The blood collection line 4 and the blood supply line 5 are each provided with pressure detection means 6, and the detected pressure information is converted into an electric signal and input to the control unit 80 of the roller pump 10.

  2 and 3 show a roller pump 10 according to an embodiment. The roller pump 10 includes a pump sleeve 70, a rotor unit 20 that is rotatably supported in the pump sleeve 70 around a first axis, a pump motor 50 that rotates the rotor unit, and power to the pump motor 50. The power supply / communication unit 60 to supply and the control part 80 which controls the roller pump 10 are provided.

  A flexible tube constituting an extracorporeal circuit is sandwiched and attached between the rotor unit 20 of the roller pump 10 and the pump sleeve 70 in a substantially U shape. When electric power is supplied to the pump motor 50 via the power supply / communication unit 60, the rotor unit 20 rotates about the first axis as a central axis to squeeze the tube and deliver blood. In the following description, the first axis is an extension of the shaft of the pump motor 50, and is indicated by XX in FIGS. The distal end side indicates the side on which the power supply / communication unit 60 in the first shaft is provided, that is, the upward direction in FIG. 3, and the proximal end side is the side in which the pump motor 50 is provided on the first shaft, That is, the downward direction of FIG. 3 is shown.

  The rotor unit 20 includes an adjustment unit 30, a roller 40, an adjustment knob 42, and a rotor base 44. The rotor base 44 is connected to the pump motor 50 on the base end side, and transmits the rotation of the pump motor 50 to the rotor unit 20 as the pump motor 50 is driven. Further, the rotor unit 20, the rotor base 44, and the pump motor 50 are rotatable in an arbitrary direction with the first axis as a central axis.

  4 and 5 show the rotor unit 20 according to the present embodiment. The rotor unit 20 is supported so as to be rotatable with respect to the first shaft inside the pump sleeve 70, and abuts on the flexible tube and tightens it, and the rotor tube 20 is rotated along with the rotation of the rotor unit 20. And a roller 40 for delivering blood. The roller 40 can be moved closer to or away from the first shaft in the radial direction by the adjusting unit 30 including the adjusting motor 32.

  The adjustment unit 30 includes an adjustment screw 31, an adjustment motor 32, a roller arm 33, and sliders 34A and 34B. The adjustment motor 32 can be arbitrarily rotated in forward and reverse directions by electric power supplied from the power supply / communication unit. The adjustment motor 32 can rotate the adjustment screw 31 around the first axis via a plurality of gears having different diameters, and can move the roller 40 closer to or away from the first axis. The adjusting screw 31 is disposed so that the longitudinal direction thereof is along the first axis, and threaded portions are provided at both ends. Furthermore, the threaded portion provided at one end of the adjusting screw 31 is threaded in the opposite direction to the other end, and the central portion is thicker than both ends.

  The pair of sliders 34 </ b> A and 34 </ b> B are fitted to threaded portions on both ends of the adjustment screw 31, and are movable along the first axis to the distal end side and the proximal end side as the adjustment screw 31 rotates. The pair of sliders 34 </ b> A and 34 </ b> B in the present embodiment has a substantially tapered shape that narrows toward the center of the adjustment screw 31.

  In the present embodiment, since the threading at one end of the adjusting screw 31 is in the opposite direction to the other end, the sliders 34A and 34B are moved along the first axis as the adjusting screw 31 rotates. Can be brought close to each other or separated from each other. In addition, since the central portion of the adjusting screw 31 is thicker than both the threaded ends, the sliders 34 </ b> A and 34 </ b> B come into contact with the central portion of the adjusting screw 31 when approaching each other to a certain distance. Therefore, it is possible to prevent the sliders 34 </ b> A and 34 </ b> B from approaching too much and the contact with the roller arm 33 being eliminated.

  The roller arm 33 supports the roller 40 and is at least partially in contact with the sliders 34A and 34B. As shown in FIG. 3, in this embodiment, the roller arm 33 is configured to come into contact with the tapered surfaces of the sliders 34A and 34B. When the sliders 34A and 34B approach and separate from each other, the roller arm 33 moves accordingly. The first axis is approached and separated in the radial direction.

  In the present embodiment, the rotation of the adjustment motor 32 is configured to be transmitted to the adjustment screw 31 via three gears. The first gear 35 is a motor-side gear assembled to the adjustment motor 32 and meshes with the second gear 36. The second gear 36 is provided on the switching plate 91 and meshes with the first gear 35 and the third gear 37. The third gear 37 is a screw-side gear assembled on the tip side of the adjustment screw 31 and meshes with the second gear 36. Here, the first gear 35 has a smaller diameter than the second gear 36, and the second gear 36 has a smaller diameter than the third gear 37.

  According to the present embodiment, it is possible to arbitrarily determine the rotation speed of the adjustment screw 31 with respect to the rotation speed of the adjustment motor 32 by appropriately adjusting the gear diameter and the number of teeth. That is, the approach / separation distance of the roller arm 40 with respect to the rotation speed of the adjustment motor 32 can be arbitrarily determined. In addition, since the rotation speed of the adjustment screw 31 is reduced as compared with the rotation speed of the adjustment motor 32, when the adjustment screw 31 rotates, a torque inversely proportional to the reduction ratio can be obtained, which is more precise and stable. Occlusion adjustment is possible.

  Further, in the present embodiment, automatic occlusion adjustment and manual occlusion adjustment can be switched. The rotor unit 20 includes a switching unit 90 for switching between a first state where automatic occlusion adjustment is possible and a second state where manual occlusion adjustment is possible. The switching unit 90 includes a switching plate 91 and a switching lever 92. The substantially disc-shaped switching plate 91 is provided on the distal end side of the roller arm 33, has an opening for inserting the shaft of the adjusting motor 32 and the adjusting screw 31, and has a switching lever 92 at the outer edge. A matching notch 93 is provided. The switching lever 92 is provided with an engaging portion that engages with the notch 93. In the first state, the both engage with each other, and the switching plate 91 cannot rotate in the circumferential direction. Is disengaged, and the switching plate 91 can be rotated in the circumferential direction.

  As shown in FIG. 7, in the first state, the first gear 35, the second gear 36, and the third gear 37 are meshed with each other, and the driving force of the adjustment motor 32 is the first to third. It is supplied to the adjusting screw via a gear, and automatic occlusion adjustment becomes possible. When the switching lever 92 is operated to release the engagement with the notch 93 and the switching plate 91 is rotated in the circumferential direction, the meshing between the first gear 35 and the second gear 36 is released. This is the second state shown. In the second state, the second gear 36 meshes with the third gear 37 and an inner peripheral gear 43 provided on the inner peripheral surface of the adjustment knob 42. The medical staff can rotate the adjustment screw 31 via the second gear 36 and the third gear 37 by rotating the adjustment knob 42 in an arbitrary direction to perform manual occlusion adjustment.

  The adjustment knob 42 is provided on the tip side of the switching plate 91, and an inner peripheral gear 43 that meshes with the second gear 36 in the second state is provided on the inner peripheral surface thereof. In such a case, when the adjustment knob 42 is rotated in the second state, the second gear 36 is also rotated. Thereby, since the adjustment screw 31 rotates via the 3rd gearwheel 37, a medical worker can obtain appropriate capping degree by rotating the adjustment knob by a desired amount.

  In the present embodiment, the roller pump 10 includes a power supply / communication unit 60 that supplies power to the control unit 80 and the adjustment motor 32 and delivers a signal to the control unit 80 that controls the adjustment motor 32. Here, the power feeding / communication unit 60 includes a power feeding coil 61, a power receiving coil 62, and signal communications 63A and 63B. Electric power can be supplied to the adjustment motor 32 in a non-contact manner using electromagnetic induction or the like between the power feeding coil 61 and the power receiving coil 62. Further, a signal generated from the control unit 80 is exchanged between the signal paths 63A and 63B.

  The control unit 80 controls the adjustment unit 30 based on the pressure in the tube lumen of the extracorporeal circuit measured by the pressure detection means 6. The pressure of the tube lumen measured by the pressure detection means 6 is input to the control unit 80, and when the pressure deviates from a predetermined range, the adjustment unit 30 is controlled via the signal paths 63A and 63B. Thus, the roller 40 is moved closer to or away from the first shaft. Thereby, the pressure of the tube lumen can be maintained within a predetermined range while maintaining the state in which the pump motor 50 is driven.

  As a specific example of the control by the control unit 80, when the pressure in the tube lumen, particularly the pressure in the tube lumen on the downstream side of the roller pump 10 is abnormally increased due to the blockage of the extracorporeal circuit, etc., the first As a step, the roller 40 is moved closer to the first axis.

  By continuing to drive the pump motor 50 with the extracorporeal circuit closed, if the pressure in the extracorporeal circuit, particularly the pressure on the downstream side of the roller pump 10, rises abnormally, the tube is automatically tightened by the roller 40. The closed pressure is released and the roller pump 10 enters an idle state where no further blood is delivered. Therefore, without stopping the pump motor 50, an abnormal pressure increase in the extracorporeal circuit is suppressed, and unintentional disconnection between the tube and each device, and damage to the hollow fiber such as an artificial lung or a dialyzer can be prevented. It becomes possible.

  After the execution of the first step, when the pressure is lower than the pressure that triggered the first step and becomes a normal value, the roller 40 is separated from the first shaft as the second step. In this way, the abnormal pressure rise is eliminated, and when the pressure in the tube lumen returns to the normal range, it is immediately readjusted to an appropriate pressure closure degree and the extracorporeal circulation can be resumed.

  The pressure increase in the tube lumen that is the trigger for starting the first step can be set to an arbitrary value of preferably 100 mmHg or more, more preferably 200 mmHg, and even more preferably 300 mmHg or more, for example, 100 mmHg, 200 mmHg, or 300 mmHg. be able to. The start trigger of the second step can be an arbitrary value of preferably 50 mmHg or more, for example, 50 mmHg as a decrease from the pressure that is the start trigger of the first step. Note that the pressure increase as the start trigger of the first step is a value increased from the reference with reference to the pressure of the tube lumen when the occlusion adjustment is performed and the driving of the rotor pump 10 is started.

  The specific numerical value of the moving amount of the roller 40 in the first step can be determined in consideration of various parameters. For example, the distance between the roller 40 and the pump sleeve 70 is compared with a state in which the occlusion adjustment is performed. Then, the roller 40 can be moved closer to the first axis so as to expand by 0.08 mm or more.

  The control unit 80 can record various parameters for obtaining an appropriate pressure closing degree. If it is set as such an aspect, the readjustment of the position of the roller 40 in a 2nd step will become easy. For example, referring to the current value, electrical resistance value, etc. of the adjustment motor 32 recorded in the control unit 80 at the time of appropriate occlusion adjustment, the roller 40 is moved relative to the first axis until the corresponding value is reached. By separating in the radial direction, it is possible to readjust to an appropriate pressure closing degree.

  In the roller pump 10 of this embodiment, since the pump motor 50 is not stopped during the readjustment of the roller 40, the extracorporeal circulation can be resumed without a time lag for restarting the pump motor 50. Furthermore, since all the series of schemes can be performed automatically, the burden on medical staff can be greatly reduced.

  It should be noted that the pressure of the tube lumen that is the trigger for starting the first step, that is, the value of the pressure of the tube lumen when the tube 40 is loosened by releasing the tightening of the tube by the roller 40 is determined by medical personnel such as an extracorporeal circulation engineer. The person may be able to set as appropriate. For example, it is possible to appropriately set the timing for releasing the pressure closure in the range of 10 mmHg to 500 mmHg. However, when the pressure in the tube lumen is 300 mmHg or more in gauge pressure, there is a risk that the connection between the tube and the device is broken and the hollow fibers such as an artificial lung and a dialyzer are damaged. For this reason, when it becomes at least 300 mmHg, it is preferable to make it the structure which loosens the tightening of a tube and releases pressure. Also, the pressure in the tube lumen that becomes the activation trigger in the second step may be appropriately set by a medical worker such as an extracorporeal circulation engineer.

  On the other hand, when a blood removal cannula that draws blood from the human body to the extracorporeal circuit or a blood removal cannula that draws blood from the surgical field sticks to a body tissue such as a blood vessel wall due to negative pressure during suction. In some cases, the pressure in the extracorporeal circuit, particularly the pressure on the upstream side of the roller pump 10, may become abnormally low. Even in this case, the pressure of the tube lumen can be maintained within a predetermined range without stopping the pump motor 50 by adjusting the position of the roller 40 by the controller 80.

  Even when the pressure becomes abnormally low, the roller 40 is moved closer to the first shaft as the first step. As a result, the roller pump 10 is in an idle state in which no further blood is delivered, and it is possible to suppress hemolysis and the like associated with abnormal pressure reduction in the extracorporeal circuit and generation of negative pressure. After the first step, when the pressure rises higher than the pressure that is the trigger for starting the first step and becomes a normal value, the roller 40 is separated from the first shaft as the second step. As a result, blood circulation can be resumed immediately.

  The pressure drop in the tube lumen serving as the activation trigger in the first step can be set to an arbitrary value of, for example, 50 mmHg or more, and the pressure increase in the tube lumen serving as the activation trigger in the second step is set to, for example, 50 mmHg. The above arbitrary values can be set. Note that the pressure drop that becomes the start trigger of the first step is a value that is reduced from the reference, based on the pressure of the tube lumen when the occlusion adjustment is performed and the driving of the rotor pump 10 is started.

  It is also known that red blood cell hemolysis occurs when the negative pressure exceeds -90 mmHg. For this reason, from the viewpoint of avoiding hemolysis, the starting trigger of the first step can be set to a value such as −50 mmHg, −70 mmHg, or −90 mmHg as a gauge pressure.

  The amount of movement of the roller 40 in the first step can be set to be separated by 0.02 mm or more, for example, compared to a state in which the distance between the roller 40 and the pump sleeve 70 is adjusted to occlusion.

  It is also possible to control as follows. When the pressure in the tube lumen of the extracorporeal circuit is reduced by 50 mmHg, as a sub-step 1 of the first step, the control unit 80 adjusts the adjustment motor 32 so that the sliders 34A and 34B fitted to the adjustment screw 31 are separated from each other. To drive the roller 40 closer to the first axis in the radial direction of the rotor unit 20. Thereafter, when the pressure in the tube lumen is further reduced by 20 mmHg (decrease by 70 mmHg from the initial value), the same control as in substep 1 is performed as substep 2 of the first step. Further, when the pressure in the tube lumen further decreases by 20 mmHg (decreases by 90 mmHg from the initial value), as substep 3 of the first step, the same control as substep 1 is continuously performed.

  The amount of movement of the roller 40 in the sub-step 1 can be set to be, for example, 0.02 mm or more apart from the state in which the distance between the roller 40 and the pump sleeve 70 is adjusted to occlusion. In sub-step 2, the distance between roller 40 and pump sleeve 70 is controlled to be further separated by 0.02 mm or more from sub-step 1, and in sub-step 3, the distance between roller 40 and pump sleeve 70 is the sub-step. Further, it can be separated from 2 by 0.02 mm or more.

  In addition, the change value of the pressure used as a trigger, the moving amount | distance of the roller 40, etc. can be suitably changed as needed. Also, instead of three sub-steps, there may be two sub-steps or four or more sub-steps.

  With such control, when the blood removal hole of the blood removal cannula sticks to a body tissue such as a blood vessel wall due to the negative pressure at the time of suction, the pressure on the upstream side of the roller pump 10 becomes abnormally low. In particular, the tightening of the tube by the roller 40 is loosened to release the pressure closure, and the roller pump 10 can be made idle. Therefore, it is possible to suppress hemolysis or the like accompanying abnormal pressure reduction or negative pressure generation in the extracorporeal circuit.

  The adjustment of the position of the rotor 40 when the abnormality is eliminated can be performed with reference to the current value, electric resistance value, etc. of the adjustment motor 32 recorded in the control unit 80 at the time of appropriate occlusion adjustment, for example. In this way, the readjustment of the pressure closing degree can be automatically performed while the pump motor 50 is driven, and the extracorporeal circulation can be resumed only by the readjustment of the pressure closing degree. Moreover, all the series of schemes can be performed automatically, and the medical staff can be freed from complicated work for re-driving the pump.

  In addition, the roller pump 10 of the present embodiment can cope with a case where the pressure in the tube lumen is increased by a post-load caused by contraction of a peripheral blood vessel or the like of a patient during surgery or an increase in blood viscosity. The control unit 80 controls the adjustment unit 30 in advance to maintain the pressure in the tube lumen within a predetermined range and a predetermined delivery amount while the pump motor 50 is driven, and blood corresponding to the afterload. Can be obtained.

  Specifically, for example, as a first step, the controller 80 causes the roller 40 to approach the first axis so that the pressure in the tube lumen of the extracorporeal circuit is 150 mmHg and the delivery amount is 4000 L / min. The pump motor 50 is driven. More specifically, the radial direction of the rotor unit 20 is set so that the roller 40 is separated from the first axis by 0.01 mm or more so that the distance between the roller 40 and the pump sleeve 70 is separated by 0.01 mm or more compared to the state in which the occlusion is adjusted. It is preferable to approach. In this case, since the cross-sectional area of the tube lumen is increased by about 5% to 10% compared to the state in which the occlusion is adjusted, the blood delivered from the roller pump 10 is not a steady flow, but depends on the magnitude of the afterload. Therefore, the delivery amount becomes appropriate, and the delivery amount can be adjusted by adjusting the pump motor 50. If the pump motor 50 is not adjusted during fluctuations in the afterload, the delivery amount is restored to the predetermined amount when the afterload is removed. However, it is also possible to adjust the pump motor 50 during the fluctuation of the afterload and readjust when the afterload is removed.

  In the present embodiment, the example in which the threaded portion provided at one end of the adjusting screw 31 of the adjusting unit 30 and the other end are threaded in the opposite direction has been described, but the present invention is not limited to such an embodiment. . The adjustment unit 30 only needs to be configured so that the roller 40 provided in the rotor unit 20 can be approached and separated in the radial direction with respect to the first shaft. On the other hand, it can be set as the structure provided with the spring member etc. urged | biased in the direction which approaches / separates to radial direction.

  In addition, although the example in which the pair of sliders 34 </ b> A and 34 </ b> B has a substantially tapered shape that narrows toward the center of the adjustment screw 31 has been described, the present invention is not limited to such an embodiment. The pair of sliders 34 </ b> A and 34 </ b> B may be configured such that when the adjustment screw 31 rotates, the roller arm 33 moves closer to and away from the first shaft in the radial direction.

  Furthermore, although the example which performs transmission of the driving force from the adjustment motor 32 to the adjustment screw 31 with three gears was shown, it is not limited to such an aspect. Transmission of the driving force from the adjusting motor 32 to the adjusting screw 31 can be performed via at least two gears having different diameters. Two gears, that is, a gear connected to the adjusting motor 32 and a gear connected to the adjusting screw 31 may be used, or four or more gears may be used.

1: Blood circuit, 10: Roller pump, 20: Rotor unit, 30: Adjustment unit, 40: Roller, 50: Pump motor, 60: Power supply / communication unit, 70: Pump sleeve, 80: Control unit, 90: Switching unit

Claims (8)

A pump sleeve to which a tube constituting a blood circuit can be attached;
A rotor unit rotatably supported with respect to a first shaft inside the pump sleeve;
A roller provided in the rotor unit so that the distance to the first shaft can be changed;
A pump motor for rotating the rotor unit;
A roller pump comprising: a controller that adjusts a distance between the roller and the first shaft when the pressure in the tube lumen deviates from a predetermined range.   When the pressure in the tube lumen rises by 100 mmHg or more, the controller causes the roller to approach the first axis, and the pressure in the tube lumen causes the roller to approach the first axis. The roller pump according to claim 1, wherein the roller is separated from the first shaft when the pressure is reduced by 50 mmHg or more from the pressure at the time.   When the pressure in the tube lumen drops by 50 mmHg or more, the control unit causes the roller to approach the first shaft, and the pressure in the tube lumen causes the roller to move away from the first shaft. The roller pump according to claim 1, wherein the roller is separated from the first shaft when the pressure increases by 50 mmHg or more.   An adjustment screw for moving the roller closer to or away from the first shaft, an adjustment motor for rotating the adjustment screw, and at least two gears having different diameters for transmitting force from the adjustment motor to the adjustment screw The roller pump according to claim 1, further comprising an adjustment unit. The at least two gears include a motor side gear attached to the adjustment motor and a screw side gear attached to the adjustment screw;
The roller pump according to claim 4, wherein the motor side gear has a smaller diameter than the screw side gear.   A pump sleeve to which a tube constituting a blood circuit can be attached, a rotor unit rotatably supported with respect to the first shaft inside the pump sleeve, and a distance between the first shaft and the first shaft can be changed. In a roller pump comprising a roller provided in the rotor unit and a pump motor that rotates the rotor unit, the pressure of the tube lumen deviates from a predetermined range without stopping the pump motor, A method for controlling a roller pump, comprising a step of changing a position of a roller. The step of changing the position of the roller includes:
A first step of causing the roller to approach the first axis when the pressure in the tube lumen rises by 100 mmHg or more;
And a second step of separating the roller from the first shaft when the pressure in the tube lumen is reduced by 50 mmHg or more from the pressure at the time of performing the first step after the first step. The control method of the roller pump of Claim 6. The step of changing the position of the roller includes:
A first step of causing the roller to approach the first shaft when the pressure in the tube lumen is reduced by 50 mmHg or more;
And a second step of separating the roller from the first shaft when the pressure in the tube lumen is increased by 50 mmHg or more from the pressure at the time of performing the first step after the first step. The control method of the roller pump of Claim 6.