Abstract: A hemodialysis system includes (i) blood tubing; (ii) a peristaltic blood pump contacting the blood tubing to pump blood through the blood tubing; (iii) a dialyzer in fluid communication with the blood tubing; (iv) first and second peristaltic dialysate pumps; (v) a dialysate heater; (vi) a plurality of pinch valves; and (vii) a cassette including a rigid structure, a heating portion, first and second dialysate pumping tubes, and a plurality of incoming tubes, the rigid structure when the cassette is mounted for operation orienting (a) the heating portion adjacent to the dialysate heater so that dialysate can be heated by the dialysate heater, (b) the first and second dialysate pumping tubes adjacent to the first and second peristaltic dialysate pumps, and (c) the plurality of incoming tubes adjacent to the plurality of pinch valves to enable the tubes to be individually closed by the pinch valves.

Abstract: A tube pump comprises a rotor configured to have a roller and to hold the roller to be able to make an orbital motion along the inner circumferential surface of the cap. The rotor includes a disk part which holds the roller on a base side, and a tube press member that engages with the disk part so that the tube does not move to the base side with respect to the disk part, seals a gap formed with respect to the inner circumferential surface of the cap, and is capable of rotating along an outer circumferential part of the disk part is provided at the outer circumferential part of the disk part.

Abstract: A tube pump comprises a rotor configured to have a roller and to hold the roller to be able to make an orbital motion along the inner circumferential surface of the cap. The rotor includes a disk part which holds the roller on a base side, and a tube press member that engages with the disk part so that the tube does not move to the base side with respect to the disk part, seals a gap formed with respect to the inner circumferential surface of the cap, and is capable of rotating along an outer circumferential part of the disk part is provided at the outer circumferential part of the disk part.

Abstract: A micropump of a peristaltic type that continuously transfers a fluid through depression of an elastic tube is disclosed. The micropump includes: a tube unit that includes the tube, a tube guide frame that fixedly holds the tube, a tube individual data storage section that stores tube individual data, and a depression mechanism section for depressing the tube; a control unit that is attachable to the tube unit, and includes a control circuit section that drives and controls a motor for driving the depression mechanism section, and a tube individual data processing section including a reader/writer unit that reads the tube individual data; and a power supply that makes an electrical supply to the control unit. In the micropump, the tube individual data is used as a basis for driving.

Abstract: A rotary cam actuated linear peristaltic pump includes a plurality of cams which actuate a plurality of pistons. The cams apply a force to the piston by way of a lifter for providing mechanical advantage so that a smaller motor may be used to rotate the cam. Each piston of a plurality of pistons is sequentially raised to the extended position to squeeze a tube so as to flow fluid through the tube.

Abstract: A tube-positioning system for loading tubing into a peristaltic pump includes a holder and a first tube segment. The holder includes a shell configured to slidably fit onto an exterior of a pump and a pair of guides extending upward from opposite side walls of the shell. The first tube segment has a fixed length and extends between the pair of guides with each end of the first tube segment secured within one of the respective guides.

Abstract: A peristaltic pump is provided that is configured to facilitate safe maintenance of the pump. The pump can comprise a pump body having a pump head and a head cover and a safety switch mechanism. The safety switch mechanism can comprise one or more sensors that allow the pump to detect whether the head cover is in an open or closed position. When the pump is powered-on, the pump can be configured to enter a maintenance mode when the safety switch detects that the head cover is in the open position.

Abstract: A peristaltic pump includes a pumping mechanism cover releasably coupled to a pumping mechanism base or gear case cover and configured to enshroud components including a roller assembly and tube. Removal of the pumping mechanism cover exposes the components to facilitate maintenance. The pumping mechanism cover may be locked into a closed position using a threaded bushing or a pivoting latch. A plurality of engagement studs may be provided to secure the pumping mechanism base to the gear case housing cover. The pumping mechanism base or gear case cover is configured for releasably engaging tubing inlet and outlet fittings. Thus, tubing may be installed or removed without having to disassemble or remove any other portion of the pumping mechanism base.

Abstract: A peristaltic pump having a casing defining a tube race, a flexible tube disposed in the tube race, and a rotor with one or more rollers adapted to act against the flexible tube. The casing has a first section having the tube race and a first part of fitting means, and a second section having the rotor and a second part of the fitting means. The first and second parts of the fitting means are a releasable snap-fit together.

Abstract: A fluid transportation system includes: an elastic tube; a tube frame having a tube guide groove to which the tube is attached in a circular arc; a cam driving wheel interior of the tube and having a rotational center coinciding with the center of the circular arc of the tube guide groove; a first cam fixed to a center shaft of the cam driving wheel; a second cam rotatably supported by the center shaft; and a plurality of fingers radially extending from the rotation center between the tube and the first and second cams and pressing the tube by the rotation of the first and second cams, wherein when the fluid transportation system starts to operate, the first and second cams produce a state in which the second cam is attached to the first cam and at least one of the plural fingers closes the tube.

Abstract: Disclosed are improved methods and apparatus for radiolabeling, particularly methods and apparatus for large scale in-line radiolabeling of products, such as proteins and antibodies.

Abstract: The invention provides a finger-type peristaltic pump (2) having a body (4) and a housing (6). The body contains two or more finger-type valves (16) and a processor (22) configured to operate the valves according to a predetermined temporo-spatial pattern. The housing has a passageway (18) configured to receive a conduit. The housing has a first position in which a conduit in the passageway is positioned adjacent to the valve fingers, and a second position in which a conduit in the passageway is not adjacent to the valve fingers. The invention also provides a housing for use in the pump of the invention.

Abstract: A method for operating a peristaltic pump having a molded flow channel contained on an elastomeric sheet that is bonded or mechanically attached to a rigid substrate. The pump head rollers are mounted radially from the axis of rotation of the pump motor and compress the elastomeric flow channels against the rigid substrate. During reflux, the pump head is positioned so that at least one of the rollers compresses the elastomeric flow channel at the input end of the peristaltic pump. Such an operation minimizes the amount of the elastomeric sheet that is exposed to high transient pressures.

Abstract: An apparatus and method are disclosed for the continuous treatment of the flow of a mixture containing liquids and solids. A pump provides the mixture to tube that includes a woven material. The liquid is filtered from the mixture, leaving a solids-enriched mixture in the tube. The tube may be flexed during the process, freeing solids trapped in the tube to flow through the center of the tube. A valve may be provided to the tube to generate a back-pressure in the system.

Abstract: The invention concerns a peristaltic cassette casing comprising a tube housing forming an arc, characterized in that it comprises tube fixing means arranged along said housing so as to prevent the longitudinal displacement of a tube arranged in said housing.

Abstract: A tubing holding device for a roller pump is disclosed. The tubing holding device is removable from the roller pump, slidably moveable and able to be opened to allow for easy exchange of tubing in roller pumps. The tubing holding device comprises a clamping mechanism that securely holds tubing in place. Tubing of various sizes may be used within a roller pump by selecting the appropriately sized tubing holding device, or by using a tubing holding device, such as one embodiment disclosed, which may be adjustable for different sizes of tubing. Roller pumps including the tubing holding devices, and methods of loading such roller pumps are also disclosed.

Abstract: The invention relates to a method and to a device for operating an electric peristaltic hose pump, in particular a hose pump for transporting fluids in medical-technical devices, in particular extracorporeal blood treatment devices. In order to monitor the regular operation of a hose pump, the power consumption of the pump or a physical variable in correlation with the power consumption, in particular the pump flow, is monitored. The pump flow includes a periodically non-altering direct component which is superimposed on a periodically altering alternating component. In order to monitor the regular operation of the hose pump, the alternating component of the power consumption in relation to the direct component of the power consumption is monitored as whether it increases and/or decreases during blood treatment.

Abstract: A connector assembly for a heat exchanger has a fitting and a mount to which the fitting couples. The fitting has an elongate body having a proximal portion and a distal portion. At the proximal portion there is a crossbar, and at the distal portion there are an inlet and an outlet that protrude away from the body. Two wings extend from the body in a direction opposite to that of the inlet and outlet. There is formed on each of the wings a locking protrusion. The mount has a top portion where there is a groove dimensioned to accept the crossbar of the fitting. A longitudinal channel is formed orthogonal to the groove in the mount. Two sidewalls extend from the mount each for accepting a corresponding one of the wings, when the fitting is coupled to the mount. Apertures are provided at the sidewalls at the wings.

Abstract: A liquid-dispensing device includes a liquid-containing unit, a flexible tube, a nozzle, and a cam mechanism. The flexible tube is connected to the liquid-containing unit. The nozzle is connected to the flexible tube. The cam mechanism includes first and second cams, and first and second cam followers. The first and second cams are co-rotatable. Each of the first and second cam followers is driven by a respective one of the first and second cams to move to a squeezing position, where each of the first and second cam followers exerts a squeezing force on the flexible tube.

Abstract: An infusion pump uses an improved shuttle mechanism to more reliably pump liquids in low volumes for medical and other purposes. The improved shuttle uses linear translation and wider, symmetric jaws to grasp infusate tubing and pump liquid infusate through the tubing. Adjustment of the linear motion allows a user to also adjust a pumping volume of the infusion pump. Other shuttles with wider jaws may also pump infusate using a rotary motion. In addition, more than one shuttle, such as two or three shuttles, may be used to approximate continuous pumping. A series of several smaller linear shuttles with sequential actuation may be used as a linear peristaltic pump for general peristaltic pump applications.

Abstract: A peristaltic pump for dispensing liquid includes a front casing portion, a rear casing snap-fitted together with the front casing portion, a rotor confined between the front casing portion and the rear casing portion, a plurality of rollers mounted in the rotor, and a flexible tube compressed at equally spaced intervals by the plurality of rollers. The pump is resistant to constant torques and vibrations caused by a machine to which it is attached so that the pump does not become loose and fall apart. In a first embodiment for low torque and low vibration operations, the pump is screwless. In a second embodiment for high torque and high vibration operations, two screws secure a synchronous gear motor to the pump.

Abstract: The invention relates to a roller pump consisting of a stator with a pump bed formed therein and a rotor for acting on a hose inserted into the pump bed in arcuate form. In accordance with the invention, the ends of the tube guided out of the pump bed cross.

Abstract: A pumping apparatus has a peristaltic drive device for pumping a medium through a line that has a compressible portion. The pump contains a one-piece shaft with offset cam segments and lamellae. The shaft may or may not include a core shaft or a continuous core region for an increase in stability. The continuous core region has cam segments offset with respect to one another and contiguous to one another. The ratio between the height and stroke of the lamellae is about 4:1 or less.

Abstract: The present invention provides an addressable multi-channel peristaltic pump. According to the invention, this pump design allows for selection and operation of one or more pump heads on a drive shaft, while locking other non-selected pump heads in a stationary position. It is possible to operate the multi-channel pump using a limited number of motors, preferably two motors: a selector motor and a dispense motor. Thus, the pump provides for pumping or dispensing of one or more fluids without the need for multiple pumps. Likewise, compared with typical single motor multi-channel systems, where all pump heads on the drive shaft must rotate at the same time, the present invention provides for selective dispensing of one or more fluids. The pumps of the present invention are suitable for any multiple fluid transfer application, including in automated multi-channel reagent dispensing systems, such as nucleic acid purification systems.

Abstract: A dialysis machine valve manifold assembly includes a plurality of pneumatic valves; a plate including a first side and a second side, the plurality of pneumatic valves mounted to the first side of the plate, the second side of the plate defining a plurality of pneumatic flow paths; and a port header mounted removably to the plate, the port header including a plurality of ports configured to connect sealingly to pneumatic tubing, the ports in fluid communication with the pneumatic valves via the pneumatic flow paths defined in the plate.

Abstract: A peristaltic pump for dispensing liquid is described and includes a front housing and a rear housing snap-fitted together to define a chamber having a recessed area and a rotor confined therein, a plurality of rollers mounted in the rotor, and a flexible tube compressed at equally spaced intervals by the plurality of rollers. The rotor undergoes a gradual increase in torque as a benefit of the recessed area, rather than an immediate high-torque load at the start of each pump cycle. Further, the pump is resistant to constant torques and vibrations caused by a machine to which it is attached so that the pump does not become loose and fall apart.

Abstract: An improved peristaltic pump whereby the elastomeric tubing communicates with the peristaltic pump in a way that allows for axial movement of the tubing thereby extending the flex life of the pump tubing. A tubing element is fitted with a flange that allows tension to be applied to the tubing in a way that changes depending upon the location of the rotor at any given time. The tension can be applied via an elastic material located between the flange and the housing or between the housing and a device that communicates with the flange. The dynamic tension reduces the amount of stress on the tubing material when the rollers first engage the tubing on the suction side of the pump and when they depart the tubing on the discharge side of the pump. The invention is particularly useful for materials that have limited axial flexibility and for those with very large axial flexibility.

Abstract: A system for delivering blood, cardioplegia solution, and other medications or fluids in a pulsatile flow pattern to a patient during cardiopulmonary bypass is disclosed. In a preferred embodiment, a pumping apparatus having at least one chamber is utilized in which a pumping action is achieved by compressing one of the chambers with a piston mechanism, while allowing the other chamber to fill with fluid via retracting its respective piston. The instantaneous flow rate of either of the chambers is determined by the speed of the piston. In a preferred embodiment, a pulsatile flow of fluid is achieved by cyclically alternating the velocity of the piston between two different speeds. A desired average flow rate and/or delivery pressure and/or constant pulse pressure is maintained by adjusting the alternating velocities at the desired frequency and duty cycle. The calculations necessary to obtain a desired average flow rate are performed by a microprocessor, which also controls the movement of the pistons.

Abstract: A tube pump includes tubes, hooks, tube receivers, three or more fingers, and a drive mechanism. The tubes each include intermediate tubes, connectors, and end tubes. The tubes are attached by engaging the connectors with the hooks provided on upper and lower sides. The intermediate tubes are provided along the tube receivers. Tube press portions of the fingers are provided between the intermediate tubes. The fingers are driven by the drive mechanism so that the tube press portions are reciprocated between a position where one of the intermediate tubes is squeezed and a position where the other of the intermediate tubes is squeezed.

Abstract: A tube pump includes: an elastic tube (14); a circular arc-shaped guiding member (16) for guiding the tube (14); and at least one pressing member (15) for pressing the tube (14) against the guide member (16). The tube pump is characterized by being provided with a recessed portion (17) in a portion of the guiding member (16), in which the tube (14) is not pressurized by the pressing member (15) and can be recessed. Thus, there can be provided a tube pump in which a negative pressure inside an ink supply passage (7) can be eliminated and air can be readily prevented from entering the ink supply passage (7) when the main tank (5) is replaced, and an ink jet recording device using the tube pump.

Abstract: A medical pump includes a chassis having a fixed seat, and a main carriage having a carriage footing for receiving a fluid delivery device and restricting its movement. An actuator automatically moves the main carriage between open and closed positions to engage the fluid delivery device to the seat. The seat establishes the position of both the main carriage and fluid delivery device in the closed position. The actuator is connected to the main carriage by a rear carriage assembly having a manual release element for disengaging the actuator from rear carriage assembly and thereby from the main carriage. A processing unit detects jam conditions by processing carriage position data and electrical load data from the actuator.

Abstract: Rotary axial peristaltic pumps, related methods and components. The rotary axial peristaltic pump generally comprises a platen having a platen surface, a tube positioned adjacent to the platen surface, cam that rotates about a rotational axis and has a cam surface that is spaced apart from the platen surface and a plurality of tube compressing fingers. The fingers move axially back and forth in sequence to sequentially compress segments or regions of the tube against the platen surface, thereby causing peristaltic movement of fluid through the tube. The fingers move back and forth on axes that are substantially parallel to the axis about which the cam rotates.

Abstract: A roller pump includes a stator with a pump bed formed therein, and a rotor for acting on a hose inserted into the pump bed in arcuate form. The ends of the hose are guided out of the pump bed in a crossed configuration.

Abstract: A peristaltic pump includes a removable carrier against which a flexible tube is pressed by rollers. The carrier includes an intermediate deformable section having an internal cylindrical surface whose axis coincides with the main axis of rotation of the rollers and lateral rigid arms arranged on both sides of the intermediate section. The free ends of the lateral arms include guides. The pump case is provided with paths on which the guides are slidable. The path directions are predefined in order to constrain the displacement of the free ends of the lateral arms and to deform the intermediate section in such a way that the radius of the internal face is modified keeping the axis thereof coinciding with the main axis, thereby making it possible to use a tube having variable characteristics.

Abstract: A peristaltic pump having a plurality of pressors which compress a tube portion according to an orderly sequence. The pump is capable of determining a fluid flow inside the tube portion. The pressors are balancing or tilting pressors pivoted around a mutual axis and operated by corresponding motion means, which push the pressors against a plane or reaction element, contrasting the pressure of the same pressors on the tube containing the fluid to be pumped.

Abstract: A peristaltic pump, for propelling liquid through a flexible pump tube, includes an outer casing having a guiding channel wherein an operating portion of the pump tube extends along the guiding channel. The peristaltic pump further includes at least two pressuring rollers supported at the outer casing in a radially movable manner which can move outwardly to press against the operating portion of the pump tube. A center driving mechanism is supported at a center portion of the outer casing to radially push the pressure rollers and to drive the pressuring rollers to concurrently rotate such that the pressuring rollers roll against the operating portion of the pump tube for continuously propelling the fluid in the pump tube in the direction of rotation.

Abstract: A peristaltic pump comprising a pump housing, a compressible pump tube positioned between rotatable occluding members and a pump tube track in the housing, where there is an opening in the pump tube track between a first occluding member and a second occluding member such that when the second occluding member has exited occlusion of the pump tube at the opening, a third occluding member completes occlusion of the pump tube thus capturing a compensating volume of fluid between the first and third occluding members, and when the second occluding member reenters occlusion at the end of the opening, it displaces the compensating volume towards the outlet of the pump tube, thus maintaining fluid velocity in the outlet stream.

Abstract: The present invention discloses a finer-type peristaltic infusion pump comprising a ribbed anvil. More specifically, a finger-type peristaltic pump, comprising a plurality of pressing-fingers, infusion-tube, and a passive interfacing mechanism is disclosed. The passive interfacing mechanism comprises of means for accommodating said flexible infusion tube and mounting the tube in a location suitable for the pressing-fingers to apply an approximated perpendicular force on said tube to squeeze it; a ribbed anvil rigidly supporting the tube on opposite side to the pressing fingers when it is pressed by said finger; said anvil comprising a plurality of ribs selected from one or more ribs of a group including a plurality of ribs oriented to face said fingers' tip, a plurality of ribs located in between said fingers, or any combination thereof.

Abstract: A peristaltic microfluidic pump. The pump comprises a pumping chamber positioned between an inlet and an outlet; a plurality of moveable fingers positioned in a wall of the pumping chamber, the fingers being arranged in a row along the wall; and a plurality of thermal bend actuators. Each actuator is associated with a respective finger such that actuation of the thermal bend actuator causes movement of the respective finger into the pumping chamber. The pump is configured to provide a peristaltic pumping action in the pumping chamber via movement of the fingers.

Abstract: A plurality of pump cassettes are connected through distribution tubing to a single inlet tube such that the inlet tube is shared by the pump cassettes through the distribution tubing. The plurality of pump cassettes may be symmetrically attached to the distribution tubing. A four-port coupling may be inserted in the distribution tubing for making connection to the inlet tube and a middle one of the pump cassettes when the number of cassettes is an odd number.

Abstract: A peristaltic pump, for propelling liquid through a flexible pump tube, includes an outer casing having a guiding channel wherein an operating portion of the pump tube extends along the guiding channel. The peristaltic pump further includes at least two pressuring rollers supported at the outer casing in a radially movable manner which can move outwardly to press against the operating portion of the pump tube. A center driving mechanism is supported at a center portion of the outer casing to radially push the pressure rollers and to drive the pressuring rollers to concurrently rotate such that the pressuring rollers roll against the operating portion of the pump tube for continuously propelling the fluid in the pump tube in the direction of rotation.

Abstract: A centrifugal fluid separation system is disclosed for centrifugally separating a composite fluid into components thereof. This centrifugal separation system includes at least a centrifugal rotor which has a composite fluid containment area, a fluid flow channel/tubing and at least one separated component collection area defined therein. A composite fluid to be separated is delivered to the fluid containment area where under centrifugal forces the composite fluid is separated into components and then from which a component travels through an outlet channel to a respective separated component fluids flowing therethrough. A centrally disposed pump is also provided to move the separated component(s) to the collection area(s). Optical sensing of the interface of the separated fluid components may be used with a clamp to stop flow. A disposable bag and tubing system is also disclosed for use with reusable rotor devices.

Abstract: A peristaltic roller pump includes a rotor carrying a pumping roller on one end and an occluding roller on the other end. Occluding roller has a number of protrusions designed to only occlude the tubing section that is located under that roller as it moves over it in order to prevent any back flow through that section of the tube. Occluding roller is designed to not cause any pumping of fluid through the section of the tubing under that roller. Such design is useful in a single-needle dialysis system and in other alternating pumping systems in which during a first phase of the pumping the fluid is moved in one direction and during the second phase of operation the fluid is moved in the opposite direction.

Abstract: Methods and apparatus for pumping and dispensing are provided in which a peristaltic pump (16, 64) pumps liquid from a package (12), and may be integrated in a dispenser (10). The peristaltic pump (64) is adapted for improved accuracy, cleaning, and maintenance. Also provided are improved tubes (18) for peristaltic pumping that are coupled to self-sealing dispensing valves (92, 104, 110, 120).

Abstract: Rotary axial peristaltic pumps, related methods and components. The rotary axial peristaltic pump generally comprises a platen having a platen surface, a tube positioned adjacent to the platen surface, cam that rotates about a rotational axis and has a cam surface that is spaced apart from the platen surface and a plurality of tube compressing fingers. The fingers move axially back and forth in sequence to sequentially compress segments or regions of the tube against the platen surface, thereby causing peristaltic movement of fluid through the tube. The fingers move back and forth on axes that are substantially parallel to the axis about which the cam rotates.

Abstract: A peristaltic pump is able to deliver accurate volumes over the life of a pump set that is operated on by the pump to drive the flow of fluid. The pump delivers fluid in small volumes or aliquots. In order to deliver fluid at any particular selected flow rate, the pump determines how often the rotor will rotate. The pump is able to calculate aliquot volume based on selected flow rate, but also on a factor that compensates for changes in the dimensions of the pump set over its life.

Abstract: A dispensing device for supplying measured quantities of batter to baking containers, and a method of operating such device use a peristaltic pump driven by a servo-motor drive. The peristaltic pump has a flexible conduit with a first end connected to a supply container for receiving batter and a second end from which the batter is dispensed. A movable pump element precisely moves batter through the flexible conduit from the first end toward the second end. A shut-off valve adjacent the second end of the flexible conduit closes the conduit when the measured quantity of batter has been dispensed. A conveyor is positioned beneath the second end of the flexible conduit for moving baking containers into position therebeneath for deposit of batter. The movable pump element has a peristaltic driver including a plurality of rollers, a drive shaft to rotate the peristaltic driver such that the rollers apply pressure to the flexible conduit, pressing the flexible conduit against a curved pressure surface of a shoe.

Abstract: The invention relates to a roller pump which comprises an abutment (31, 52), at least one roller (51) and a casing (2, 3, 6). A pump hose (42) is squeezed between the roller (51) and the abutment (31, 52). A hinge (5) connects the abutment (31, 52) and the casing (2, 3, 6) pivotably, the axis of the hinge (5) being parallel to the plane of the pump hose (42). The invention further relates to a roller pump which comprises a resilient roll member (52) which is fixed to the abutment (31, 52). The pump hose (42) is pressed against the resilient roll member (52). The invention additionally relates to a roller pump which comprises two roller gears (37; 162). Each roller gear being torque-proof connected to one of the two rollers (51; 169). The two roller gears (37; 162) engage with another gear (33; 161, 160) for ensuring zero relative velocity of the portion of the rollers (35; 142) squeezing the pump hose (42) with respect to the squeezed portions of the pump hose (42).

Abstract: A micropump that includes: a tube frame including an elastic tube, and a tube guide groove for attachment of the tube in the form of an arc; a cam drive wheel whose rotation center is the same as an arc center of the tube guide groove, and moves in response to a motor that can be rotated in forward and reverse directions; a first cam that is axially fixed to a center axis of the cam drive wheel, and is provided with a finger depression section at a circumferential portion thereof; a second cam that is pivotally supported by the center axis of the cam drive wheel to be able to rotate, and is provided with a finger depression section at a circumferential portion thereof; and a plurality of fingers provided between the tube and the respective finger depression sections of the first and second cams radially from the rotation center.

Abstract: A single piece of extruded peristaltic roller pump tubing may have an inside diameter and outside diameter and wall thickness that may vary from one segment to next along its length. The tube may be formed with an atrial segment having an OD that is larger than the ventricular OD. Also, the arterial segment wall can be distensible and may be fluted. A peristaltic pump head assembly may have a C-shaped tube-holder which has no moving parts; secures the tubing 10 in pump assembly without the clamps, flanges or other tube-attaching devices; and provides a safer method for inserting the tubing into the pump head assembly. The inner diameter of the C-shaped tube-holder may be smaller than the OD of the atrial segment such that the atrial segment becomes snuggly wedged in the holder and prevents the incremental migration of the tubing through the roller raceway in the direction of the pump roller assembly rotation.