Patent Description:
The disclosure relates generally to medical devices, systems, and/or methods for dampening pressure fluctuations within a medical fluid management system.

In some fluid management systems, peristaltic or membrane pumps may be used which cause a pulsatile or non-continuous flow of fluid into (infusion) and/or out of (suction) a medical device and/or a body cavity or lumen. Peristaltic or membrane pumps may have certain desirable qualities depending upon the procedure being performed. However, the pressure fluctuations that result from the use of peristaltic or membrane pumps may be undesirable in some situations. There is an ongoing need to provide alternative components of fluid management systems to reduce pressure fluctuations of an inflow of fluid and/or an outflow of fluid through the fluid management system.

Relevant prior art is for instance disclosed in documents <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT> and <CIT>.

A fluid management system according to the present invention comprises the technical features as defined in independent claim <NUM>.

In a first aspect, a fluid management system may comprise a fluid pump capable of generating a pulsatile flow of fluid; a fluid pathway for transporting the pulsatile flow of fluid from a fluid source through the fluid pump to a medical device; a dampening element in fluid communication with the fluid pathway, the dampening element comprising one or more barrels, each barrel including a movable seal member disposed within the barrel and a biasing member disposed within the barrel and engaged with the movable seal member, the dampening element being responsive to pressure fluctuations of the pulsatile fluid flow to actively dampen the pressure fluctuations and smoothen the pulsatile fluid flow; and a fluid flow sensor disposed along the fluid pathway between the dampening element and the medical device to measure a flow rate of the smoothened pulsatile fluid flow in both flow directions of the fluid pathway.

In addition or alternatively, the dampening element may be capable of actively dampening the pressure fluctuations in both flow directions.

In addition or alternatively, the biasing member may be an elastic element.

In addition or alternatively, the elastic element may be a spring.

In addition or alternatively, the elastic element may be in compression.

In addition or alternatively, the elastic element may be in tension.

In addition or alternatively, the biasing member may be a gas, such as a gas at atmospheric pressure (e.g., atmospheric air) or a compressed gas.

In addition or alternatively, the biasing member may be a vacuum or a partial vacuum.

In addition or alternatively, the movable seal member may include at least one sealing element extending around a perimeter of the movable seal member.

In addition or alternatively, the fluid management system may further comprise a pressure relief port.

In addition or alternatively, the pressure relief port may be opened by axial translation of the movable seal member.

In addition or alternatively, each barrel may include an adjustable cap configured to adjust a working length of its barrel.

In addition or alternatively, each adjustable cap may threadably engage its respective barrel.

In addition or alternatively, a fluid management system may comprise a fluid pump capable of generating a pulsatile flow of fluid; a fluid pathway for transporting the pulsatile flow of fluid from a fluid source through the fluid pump to a medical device; a dampening element in fluid communication with the fluid pathway, the dampening element comprising a first barrel and a second barrel, the dampening element being responsive to pressure fluctuations of the pulsatile fluid flow to actively dampen the pressure fluctuations and smoothen the pulsatile fluid flow. The first barrel may include a first movable seal member disposed within the first barrel and a first biasing member disposed within the first barrel and engaged with the first movable seal member. The second barrel may include a second movable seal member disposed within the second barrel and a second biasing member disposed within the second barrel and engaged with the second movable seal member.

In addition or alternatively, the first barrel dampens the pulsatile fluid flow in a distal direction.

In addition or alternatively, the second barrel dampens the pulsatile fluid flow in a proximal direction.

In addition or alternatively, the first barrel may be independent of the second barrel.

In addition or alternatively, the first barrel and the second barrel may be formed within a single monolithic structure.

In addition or alternatively, a fluid management system may comprise a fluid pump capable of generating a pulsatile flow of fluid; a fluid pathway for transporting the pulsatile flow of fluid from a fluid source through the fluid pump to a medical device; a dampening element in fluid communication with the fluid pathway, the dampening element comprising a first barrel and a second barrel, the dampening element being responsive to pressure fluctuations of the pulsatile fluid flow to actively dampen the pressure fluctuations and smoothen the pulsatile fluid flow; and a fluid flow sensor disposed along the fluid pathway between the dampening element and the medical device to measure a flow rate of the pulsatile fluid flow in both flow directions of the fluid pathway. The first barrel may include a first movable seal member disposed within the first barrel and a first biasing member disposed within the first barrel and engaged with the first movable seal member, the first barrel being configured to dampen the pressure fluctuations in a distal direction. The second barrel may include a second movable seal member disposed within the second barrel and a second biasing member disposed within the second barrel and engaged with the second movable seal member, the second barrel being configured to dampen the pressure fluctuations in a proximal direction. The first barrel and the second barrel may both be positioned between the fluid pump and the fluid flow sensor.

While aspects of the disclosure are amenable to various modifications and alternative forms, specifics thereof have been shown by way of example in the drawings and will be described in detail. It should be understood, however, that the intention is not to limit aspects of the disclosure to the particular embodiments described.

The following description should be read with reference to the drawings, which are not necessarily to scale, wherein like reference numerals indicate like elements throughout the several views. The detailed description and drawings are intended to illustrate but not limit the present disclosure.

The detailed description and drawings illustrate example embodiments of the claimed invention. However, in the interest of clarity and ease of understanding, while every feature and/or element may not be shown in each drawing, the feature(s) and/or element(s) may be understood to be present regardless, unless otherwise specified. As such, in any given figure, some features may not be shown, or may be shown schematically, for simplicity. Additional details regarding some components, configurations, and/or embodiments may be illustrated in other figures in greater detail.

The term "extent" may be understood to mean a greatest measurement of a stated or identified dimension, unless the extent or dimension in question is preceded by or identified as a "minimum", which may be understood to mean a smallest measurement of the stated or identified dimension. For example, "outer extent" may be understood to mean an outer dimension, "radial extent" may be understood to mean a radial dimension, "longitudinal extent" may be understood to mean a longitudinal dimension, etc. Each instance of an "extent" may be different (e.g., axial, longitudinal, lateral, radial, circumferential, etc.) and will be apparent to the skilled person from the context of the individual usage. Generally, an "extent" may be considered a greatest possible dimension measured according to the intended usage, while a "minimum extent" may be considered a smallest possible dimension measured according to the intended usage. In some instances, an "extent" may generally be measured orthogonally within a plane and/or cross-section, but may be, as will be apparent from the particular context, measured differently - such as, but not limited to, angularly, radially, circumferentially (e.g., along an arc), etc..

The terms "monolithic" and "unitary" shall generally refer to an element or elements made from or consisting of a single structure or base unit/element. A monolithic and/or unitary element shall exclude structure and/or features made by assembling or otherwise joining multiple discrete structures or elements together.

<FIG> is a schematic view of a fluid management system. The fluid management system may include a fluid reservoir, such as a fluid source <NUM>. The fluid source <NUM> may include a filtering element <NUM> sized and configured to filter impurities, debris, or other unwanted elements from a fluid <NUM> so that filtered fluid <NUM> may be recirculated through the fluid management system. In some instances, the filtering element <NUM> may be located in the fluid reservoir to filter fluid returning to the reservoir. In other instances, the filtering element <NUM> may be arranged in the fluid pathway of fluid returning to the fluid source <NUM>. The fluid management system may include a fluid pump <NUM> capable of generating a non-continuous or pulsatile flow of fluid. In some instances, the fluid pump <NUM> may be a roller or peristaltic pump, or a membrane pump, for example. In at least some embodiments, the fluid pump <NUM> may be capable of generating a pulsatile flow of fluid in both a distal direction (i.e., fluid inflow from the pump to a patient) and a proximal direction (i.e., fluid outflow from a patient to the pump).

According to the invention as claimed, the fluid management system includes a fluid pathway for transporting the pulsatile flow of fluid from the fluid source <NUM> through the fluid pump <NUM> to a medical device <NUM>, such as an endoscope, a tissue resection device, etc. In some embodiments, the fluid pathway may include an inflow or infusion line <NUM> disposed between the fluid source <NUM> and/or the filtered fluid and the fluid pump <NUM>. The infusion line <NUM> may be configured for single-direction and/or flow of fluid in a distal direction (e.g., infusion, positive pressure, etc.) from the fluid source <NUM> to the fluid pump <NUM>. In some embodiments, the infusion line <NUM> may include a one-way valve configured to prevent retrograde or proximal flow of fluid back toward and/or into the fluid source <NUM>. In some embodiments, the one-way valve may be disposed within the infusion line <NUM>, at a proximal end or a distal end of the infusion line <NUM>, within the fluid source <NUM>, and/or within the fluid pump <NUM>. In some embodiments, the fluid pathway may include an outflow or return line <NUM> disposed between the fluid source <NUM> and the fluid pump <NUM>. The return line <NUM> may be configured for single-direction and/or flow of fluid in a proximal direction (e.g., suction, negative pressure, etc.) from the fluid pump <NUM> to the fluid source <NUM>. In some embodiments, the return line <NUM> may include a one-way valve configured to prevent distal flow of fluid back toward and/or into the fluid pump <NUM>. In some embodiments, the one-way valve may be disposed within the return line <NUM>, at a proximal end or a distal end of the return line <NUM>, within the fluid source <NUM>, and/or within the fluid pump <NUM>.

In some embodiments, the fluid pathway may include a first segment <NUM> disposed between the fluid pump <NUM> and a dampening element <NUM> disposed between the fluid pump <NUM> and the medical device <NUM>. The first segment <NUM> of the fluid pathway may be configured for fluid flow in both the distal direction and the proximal direction depending on the control of the fluid pump <NUM>, such as the rotational direction of the fluid pump <NUM>. The fluid pathway may include a second segment <NUM> disposed between the dampening element <NUM> and the medical device <NUM>. The second segment <NUM> of the fluid pathway may be configured for fluid flow in both the distal direction and the proximal direction depending on the control of the fluid pump <NUM>, such as the rotational direction of the fluid pump <NUM>. In some embodiments, additional segments may be included between individual elements and/or structures of the fluid management system. In some embodiments, the fluid pathway may optionally include a connector <NUM> configured to attach, couple, and/or assemble various elements of the fluid management system. The connector <NUM> (and/or multiple connectors <NUM>) may permit the addition of and/or the interchangeability of multiple elements of the fluid management system. For example, the dampening element <NUM> may be attached, coupled, and/or assembled to the first segment <NUM> of the fluid pathway with a first connector <NUM> disposed therebetween. Similarly, a second connector <NUM> (e.g., <FIG>) may be disposed between the dampening element <NUM> and the second segment <NUM> of the fluid pathway. In some embodiments, the dampening element <NUM> may include the first connector <NUM> and/or the second connector <NUM>. For example, in some embodiments, the connector <NUM> (the first and/or the second connector(s) <NUM> discussed above) may be incorporated into and/or monolithically formed with the dampening element <NUM> such that lengths of tubing, defining the fluid pathways from the dampening element <NUM>, may be attached to the dampening element <NUM> and extend therefrom. Other arrangements and/or configurations are also contemplated.

In some embodiments, the fluid management system may include a fluid flow sensor <NUM> disposed along the fluid pathway between the dampening element <NUM> and the medical device <NUM> to measure a flow rate of the pulsatile fluid flow in the distal direction (i.e. fluid inflow), in the proximal direction (i.e., fluid outflow), and/or in both flow directions (e.g., in the distal direction and the proximal direction). In one example, there is a single fluid pathway which carries flow in both the distal direction and the proximal direction, and the fluid flow sensor <NUM> is capable of measuring the flow rate of the pulsatile fluid flow in either flow direction or in both flow directions of the fluid pathway. Other arrangements and/or configurations are also contemplated.

According to the invention as claimed, the fluid management system includes a controller <NUM>. The controller <NUM> is operatively connected to and/or in communication with the fluid flow sensor <NUM> and the fluid pump <NUM>. The fluid flow sensor <NUM> may output a signal to the controller <NUM> indicative of the flow rate of the pulsatile fluid flow through the second segment <NUM> of the fluid pathway. The controller <NUM> may be configured to adjust and/or control the fluid pump <NUM> in order to adjust and/or control the pulsatile fluid flow to a desired flow rate. In some embodiments, if the flow rate of the pulsatile fluid flow is outside of a predetermined range, the controller <NUM> may stop the fluid pump <NUM> and/or terminate the pulsatile fluid flow.

In some embodiments, the fluid management system may include one or more, or a plurality of pressure sensors in the fluid pathway for measuring the pressure of the fluid therein. The pressure sensor(s) may output a signal to the controller <NUM> indicative of the pressure of the pulsatile fluid flow through the fluid pathway. The controller <NUM> may be configured to adjust and/or control the fluid pump <NUM> in order to adjust and/or control the pulsatile fluid flow based on the sensed fluid pressure. In some embodiments, if the pressure of the pulsatile fluid flow is outside of a predetermined range, the controller <NUM> may stop the fluid pump <NUM> and/or terminate the pulsatile fluid flow.

In some instances the fluid pump <NUM> and the controller <NUM> may be capital equipment intended for multiple uses, whereas the dampening element <NUM>, flow sensor <NUM> and associated tubing forming the fluid pathway may be part of a disposable tubing set intended to be disposed of after use. Thus, a new tubing set, including a new dampening element <NUM>, flow sensor <NUM> and associated tubing may be used for each medical procedure, while the fluid pump <NUM> and controller <NUM> are reused.

<FIG> illustrates a graph of positive fluid flow Q (e.g., infusion) versus time T over one cycle of the fluid pump <NUM> with and without the dampening element <NUM>. Without the dampening element <NUM>, the graph has a pronounced curve showing fluctuations in fluid pressure and/or fluid flow through the cycle. A pulsatile pressure cycle C may have positive and negative slopes indicated by the solid line Q1 - which represents flow without the dampening element <NUM>. The pulsatile pressure cycle C, if undampened, causes the fluid flow rate to increase above and fall below the dotted line Q2 - which represents desired smoothened flow with the dampening element <NUM>. With the dampening element <NUM> in place, a portion of the fluid volume (+dv) is "stored" within the dampening element <NUM>, as will be discussed herein, as the flow rate rises above the dotted line Q2, thereby limiting the flow rate past the dampening element <NUM> to the dotted line Q2. The stored fluid volume (+dv) may be returned to the fluid flow when the pulsatile pressure cycle C decreases below the dotted line Q2, which would otherwise create a negative volume (-dv), if not dampened by the dampening element <NUM>. The use of the dampening element <NUM> allows the "stored" fluid volume (+dv) to be "given back" to the fluid pathway and negate the negative volume (-dv) to smoothen the flow rate at or near the desired flow rate represented by the dotted line Q2. Accordingly, the dampening element <NUM> permits the fluid flow Q to be maintained at a more consistent level with pressure and/or fluid flow fluctuations that are reduced in quantity and/or magnitude.

When a positive pressure pulse (e.g., distal flow) is created during infusion, fluid enters one or more barrels of the dampening element <NUM>, displacing fluid volume within the one or more barrels to move a movable seal member and/or a biasing member, thereby storing fluid to compensate for the positive volume (+dv) with respect to the desired flow Q2. When the positive pulsatile fluid pressure and/or flow decreases below the desired flow Q2, the biasing member of the dampening element <NUM> pushes fluid out of the one or more barrels of the dampening element <NUM> and back into the fluid pathway, thereby releasing stored fluid to compensate for the negative volume (-dv) with respect to the desired flow Q2. The discharge will create a smoother and/or steady fluid flow at the fluid flow sensor <NUM> downstream of the dampening element <NUM>. The biasing member (via the movable seal member) responds to an increased state of the pulsatile fluid flow in the fluid pathway by deflecting and permitting the movable seal member to move away from its initial state or position, and later returns the movable seal member to its initial state or position in a decreased state of the pulsatile fluid flow in the fluid pathway.

<FIG> illustrates a graph of negative fluid flow Q (e.g., suction) versus time T over one cycle of the fluid pump <NUM> with and without the dampening element <NUM>. Without the dampening element <NUM>, the graph has a pronounced curve showing fluctuations in fluid pressure and/or fluid flow through the cycle. A pulsatile pressure cycle C may have negative and positive slopes indicated by the solid line Q1' - which represents flow without the dampening element <NUM>. The pulsatile pressure cycle C, if undampened, causes the fluid flow rate to increase above and fall below the dotted line Q2' - which represents desired smoothened flow with the dampening element <NUM>. With the dampening element <NUM> in place, a portion of the fluid volume (+dv) is "stored" within the dampening element <NUM>, as will be discussed herein, as the flow rate rises above the dotted line Q2' and then returned to the fluid flow when the pulsatile pressure cycle C decreases below the dotted line Q2', which would otherwise create a negative volume (-dv). The dampening element <NUM> may be configured to release a portion of the stored fluid volume into the fluid flow path to compensate for the negative fluid volume (-dv) with respect to the desired flow Q2', thereby maintaining the flow rate distal of the dampening element <NUM> to the dotted line Q2'. With the dampening element <NUM> in place, a portion of the fluid volume (+dv) is "stored" within the dampening element <NUM>, and then allow the "stored" fluid volume (+dv) to be "given back" or released to the fluid pathway to offset and/or compensate for the negative volume (-dv) to smoothen the flow rate at or near the desired flow rate represented by the dotted line Q2'. Accordingly, the dampening element <NUM> permits the fluid flow Q to be maintained at a more consistent level with pressure and/or fluid flow fluctuations that are reduced in quantity and/or magnitude.

When the negative pulsatile fluid pressure and/or flow increases (e.g., the negative slope) during aspiration or suction (e.g., proximal flow), fluid is drawn out of one or more barrels of the dampening element <NUM> and back into the fluid pathway, thereby releasing stored fluid to compensate for the negative volume (-dv) with respect to the desired flow Q2'. The release will create a smoother and/or steady fluid flow at the fluid flow sensor <NUM> downstream of the dampening element <NUM>. When a negative pressure pulse (e.g., proximal flow) during aspiration or suction subsides (e.g., negative pressure diminishes), fluid enters the one or more barrels of the dampening element <NUM>, filling the fluid volume within the one or more barrels as a biasing member displaces a movable seal member away from the fluid pathway, thereby storing fluid to later compensate for the negative volume (-dv) with respect to the desired flow Q2' as negative pressure increases. The biasing member (via the movable seal member) responds to a decreased state of the negative pulsatile fluid flow in the fluid pathway by urging the movable seal member to move away from the fluid pathway, and later permits the movable seal member to be drawn toward the fluid pathway in an increased state of the pulsatile fluid flow in the fluid pathway.

The dampening element <NUM> may be capable of actively dampening the pressure fluctuations of the pulsatile fluid flow in the distal direction (e.g., inflow or infusion), in the proximal direction (e.g., outflow or aspiration), and/or in both flow directions (e.g., in the distal direction and the proximal direction), depending upon the configuration of the dampening element <NUM> used.

<FIG> illustrates a partial cross-sectional view of one example of the dampening element <NUM>. The dampening element <NUM> may be positioned and/or disposed between the first segment <NUM> of the fluid pathway and the second segment <NUM> of the fluid pathway. The dampening element <NUM> may be in fluid communication with the fluid pathway, and in some instances the dampening element <NUM> may be provided as a disposable tubing set with tubing extending from the dampening element <NUM> defining the first segment <NUM> and/or the second segment <NUM>, which may be removably engaged with the fluid pump <NUM> for moving fluid therethrough. The dampening element <NUM> may comprise one or more chambers, such as cylinders or barrels <NUM> having an opening or port (such as a single opening or port) in fluid communication with the fluid pathway, each barrel <NUM> including a movable seal member <NUM> disposed within the barrel <NUM> (and/or a lumen defined by an inner surface of the barrel <NUM>), a biasing member <NUM> disposed within the barrel <NUM> (and/or the lumen defined by the barrel <NUM>) and engaged with the movable seal member <NUM>, and a cap <NUM> secured to the barrel <NUM> opposite the fluid pathway. The lumen of the barrel <NUM> may be a cylindrical lumen with the movable seal member <NUM> sealingly engaged with the cylindrical inner surface defining the lumen. The cap <NUM> may be selectively lockable onto the barrel <NUM> and/or removable from the barrel. As mentioned above, in some embodiments, the dampening element <NUM> may include the first connector <NUM> and/or the second connector <NUM> for connecting the dampening element <NUM> with tubing of the tubing set. In the example of <FIG>, the first connector <NUM> may couple proximal tubing to the dampening element <NUM> and extend proximally therefrom to the pump <NUM> and the second connector <NUM> may couple distal tubing to the dampening element and extend distally therefrom to the medical device <NUM>. Although the first connector <NUM> and the second connector <NUM> are illustrated, this is not intended to be limiting. Some suitable, but non-limiting, examples of materials for the dampening element <NUM>, the one or more barrels <NUM>, the movable seal member <NUM>, the biasing member <NUM>, and/or the cap <NUM> are discussed below.

In some embodiments, a first end <NUM> of each of the one or more barrels <NUM> (and/or each of the lumens defined by the one or more barrels <NUM>) may include a port in fluid communication with the fluid pathway, and the cap <NUM> may be secured to an opposing second end <NUM> of the barrel <NUM> (and/or the lumen defined by the barrel <NUM>). The movable seal member <NUM> may be disposed within the barrel <NUM> (and/or the lumen defined by the barrel <NUM>) between the port leading to the fluid pathway and the cap <NUM>. The movable seal member <NUM> may be configured to sealingly engage an inner surface and/or an inner wall of the barrel <NUM>. In some embodiments, the movable seal member <NUM> may include at least one sealing element <NUM> extending around a perimeter of the movable seal member <NUM> and configured to sealingly engage the inner surface and/or the inner wall of the barrel <NUM>. For example, in some embodiments, the at least one sealing element <NUM> may include at least one O-ring (e.g., one O-ring, two O-rings, three O-rings, etc.) extending around the movable seal member <NUM> and configured to sealingly engage the inner surface and/or the inner wall of the barrel <NUM>. Some suitable, but non-limiting, examples of materials for the at least one sealing element <NUM> include but are not limited to thermoset elastomers, silicone rubbers, butyl rubbers, and/or polyisoprene.

The movable seal member <NUM> may be configured to translate axially within the one or more barrels <NUM> and/or within the lumen defined by the one or more barrels <NUM>. In some embodiments, using two or more sealing elements <NUM> may help to prevent tilting, cocking, and/or wedging of the movable seal member <NUM> within the barrel <NUM> and/or the lumen defined by the barrel <NUM>. The dampening element <NUM> may be configured to be responsive to pressure fluctuations of the pulsatile fluid flow to actively dampen the pressure fluctuations and smoothen the pulsatile fluid flow. In the example of <FIG>, the biasing member <NUM> may be an elastic element. In some embodiments, the elastic element may be a spring (e.g., compression spring), a compressible member, or other similar structure or element. In the example of <FIG>, the elastic element may be secured in compression or equilibrium within the barrel <NUM> between the movable seal member <NUM> and the cap <NUM>. Accordingly, the dampening element <NUM> may be configured to actively dampen pressure fluctuations of the pulsatile fluid flow in the distal direction (e.g., positive flow; during infusion). The biasing member <NUM> may bias and/or urge the movable seal member <NUM> toward and/or into an initial position proximate the first end <NUM> or otherwise position the movable seal member <NUM> toward the first end <NUM>. The movable seal member <NUM>, in the initial position, may be at the first end <NUM> of the barrel <NUM> immediately adjacent to the port of the barrel <NUM> in fluid communication with the fluid pathway and/or the first segment <NUM> and/or the second segment <NUM>.

As fluid flow and/or pressure increases, fluid may flow into the barrel <NUM> through the port and apply a force against the movable seal member <NUM>, thereby urging the movable seal member <NUM> away from the fluid pathway and/or away from the initial position at the first end <NUM> and toward the second end <NUM> of the barrel <NUM> when the force exceeds the biasing force of the biasing member <NUM>, and the biasing member <NUM> may be compressed. This permits a portion of the fluid volume to be stored within the one or more barrels <NUM> of the dampening element <NUM> to compensate for the positive volume (+dv), which results in a reduced peak pressure and/or flow rate through the fluid pathway downstream of the dampening element <NUM>. The fluid volume that may be "stored" within the dampening element <NUM> may be calculated as the product of the cross-sectional area of the lumen of the barrel <NUM> and the axial displacement, length, or distance the movable seal member <NUM> is moved away from the initial position (e.g., dv = A * L). The biasing force exerted by the elastic element (e.g., the biasing member <NUM>) may be calculated using Hooke's law (e.g., F = -kx; where k is the rate or spring constant and x is the displacement length of the elastic element from its equilibrium position).

In at least some embodiments wherein the biasing member <NUM> includes the elastic element, the cap <NUM> may include a vent fluidly connecting the interior of the barrel <NUM> (e.g., the lumen defined by the barrel <NUM>) with outside atmosphere to prevent compressed gas from modifying or influencing the biasing force of the elastic element. For example, a portion of the barrel <NUM> and/or the lumen defined by the barrel <NUM> further defined by a side of the movable seal member <NUM> opposite the fluid pathway and/or the at least one sealing element <NUM> axially farthest away from the fluid pathway may be excluded from the fluid pathway and/or may not be fluidtight. Alternatively, in some embodiments, the cap <NUM> may include a seal member rendering the portion of the barrel <NUM> and/or the lumen defined by the barrel <NUM> further defined by the side of the movable seal member <NUM> opposite the fluid pathway and/or the at least one sealing element <NUM> axially farthest away from the fluid pathway fluidtight, and any trapped gas within the barrel <NUM> may add to the biasing force of the elastic element as the elastic element and the trapped gas within the barrel <NUM> are compressed by axial translation of the movable seal member <NUM> toward the second end <NUM>.

<FIG> illustrates a partial cross-sectional view of another example of the dampening element <NUM>. The dampening element <NUM> may be positioned and/or disposed between the first segment <NUM> of the fluid pathway and the second segment <NUM> of the fluid pathway. The dampening element <NUM> may be in fluid communication with the fluid, and in some instances the dampening element <NUM> may be provided as a disposable tubing set with tubing extending from the dampening element <NUM> defining the first segment <NUM> and/or the second segment <NUM>, which may be removably engaged with the fluid pump <NUM> for moving fluid therethrough. The dampening element <NUM> may comprise one or more chambers, such as cylinders or barrels <NUM> having an opening or port (such as a single opening or port) in fluid communication with the fluid pathway, each barrel <NUM> including a movable seal member <NUM> disposed within the barrel <NUM> (and/or a lumen defined by an inner surface of the barrel <NUM>), a biasing member <NUM> disposed within the barrel <NUM> (and/or the lumen defined by the barrel <NUM>) and engaged with the movable seal member <NUM>, and a cap <NUM> secured to the barrel <NUM> opposite the fluid pathway. The lumen of the barrel <NUM> may be a cylindrical lumen with the movable seal member <NUM> sealingly engaged with the cylindrical inner surface defining the lumen. The cap <NUM> may be selectively lockable onto the barrel <NUM> and/or removable from the barrel. As mentioned above, in some embodiments, the dampening element <NUM> may include the first connector <NUM> and/or the second connector <NUM> for connecting the dampening element <NUM> with tubing of the tubing set. In the example of <FIG>, the first connector <NUM> may couple proximal tubing to the dampening element <NUM> and extend proximally therefrom to the pump <NUM> and the second connector <NUM> may couple distal tubing to the dampening element and extend distally therefrom to the medical device <NUM>. Although the first connector <NUM> and the second connector <NUM> are illustrated, this is not intended to be limiting. Some suitable, but non-limiting, examples of materials for the dampening element <NUM>, the one or more barrels <NUM>, the movable seal member <NUM>, the biasing member <NUM>, and/or the cap <NUM> are discussed below.

In some embodiments, the first end <NUM> of each of the one or more barrels <NUM> (and/or each of the lumens defined by the one or more barrels <NUM>) may include a port in fluid communication with the fluid pathway, and the cap <NUM> may be secured to the opposing second end <NUM> of the barrel <NUM> (and/or the lumen defined by the barrel <NUM>). The movable seal member <NUM> may be disposed within the barrel <NUM> (and/or the lumen defined by the barrel <NUM>) between the port leading to the fluid pathway and the cap <NUM>. The movable seal member <NUM> may be configured to sealingly engage the inner surface and/or the inner wall of the barrel <NUM>. In some embodiments, the movable seal member <NUM> may include at least one sealing element <NUM> extending around the perimeter of the movable seal member <NUM> and configured to sealingly engage the inner surface and/or the inner wall of the barrel <NUM>. For example, in some embodiments, the at least one sealing element <NUM> may include at least one O-ring (e.g., one O-ring, two O-rings, three O-rings, etc.) extending around the movable seal member <NUM> and configured to sealingly engage the inner surface and/or the inner wall of the barrel <NUM>. Some suitable, but non-limiting, examples of materials for the at least one sealing element <NUM> include but are not limited to thermoset elastomers, silicone rubbers, butyl rubbers, and/or polyisoprene.

The movable seal member <NUM> may be configured to translate axially within the one or more barrels <NUM> and/or within the lumen defined by the one or more barrels <NUM>. In some embodiments, using two or more sealing elements <NUM> may help to prevent tilting, cocking, and/or wedging of the movable seal member <NUM> within the barrel <NUM> and/or the lumen defined by the barrel <NUM>. The dampening element <NUM> may be configured to be responsive to pressure fluctuations of the pulsatile fluid flow to actively dampen the pressure fluctuations and smoothen the pulsatile fluid flow. In the example of <FIG>, the biasing member <NUM> may be an elastic element. In some embodiments, the elastic element may be a spring (e.g., compression spring), a compressible member, or other similar structure or element. In the example of <FIG>, the elastic element may be secured in compression or equilibrium within the barrel <NUM> between the movable seal member <NUM> and first end <NUM> of the barrel <NUM>. Accordingly, the dampening element <NUM> may be configured to actively dampen pressure fluctuations of the pulsatile fluid flow in the proximal direction (e.g., negative flow; during suction). The biasing member <NUM> may bias and/or urge the movable seal member <NUM> toward and/or into an initial position proximate the second end <NUM> or otherwise position the movable seal member <NUM> toward the second end <NUM>. The movable seal member <NUM>, in the initial position, may be at the second end <NUM> of the barrel <NUM> immediately adjacent to and/or in contact with the cap <NUM>.

During pulsatile fluid flow in the distal direction (e.g., positive flow; during infusion) and/or during periods of low flow and low suction in the proximal direction (e.g., negative flow; during suction), fluid may flow into and/or be stored within the barrel <NUM> and/or the lumen defined by the barrel <NUM> between the first end <NUM> and the movable seal member <NUM>. As the suction or negative pressure increases in magnitude to a point where the suctioning force exceeds the biasing force of the biasing member <NUM>, fluid may be drawn out of the barrel <NUM>, thereby "pulling" the movable seal member <NUM> away from the cap <NUM> and/or away from the initial position at the second end <NUM> and toward the first end <NUM> of the barrel <NUM>, and the biasing member <NUM> may be compressed. This permits a portion of the fluid volume to be released from the one or more barrels <NUM> of the dampening element <NUM> to compensate for the negative volume (-dv), which results in a smoothened pressure and/or flow rate through the fluid pathway.

In at least some embodiments wherein the biasing member <NUM> includes the elastic element, the cap <NUM> may include a vent fluidly connecting the interior of the barrel <NUM> (e.g., the lumen defined by the barrel <NUM>) with outside atmosphere to prevent compressed gas from modifying or influencing the biasing force of the elastic element. For example, the portion of the barrel <NUM> and/or the lumen defined by the barrel <NUM> further defined by the side of the movable seal member <NUM> opposite the fluid pathway and/or the at least one sealing element <NUM> axially farthest away from the fluid pathway may be excluded from the fluid pathway and/or may not be fluidtight. Alternatively, in some embodiments, the cap <NUM> may include a seal member rendering the portion of the barrel <NUM> and/or the lumen defined by the barrel <NUM> further defined by the side of the movable seal member <NUM> opposite the fluid pathway and/or the at least one sealing element <NUM> axially farthest away from the fluid pathway fluidtight, and any gas (or lack thereof) trapped within the barrel <NUM> may add to the biasing force of the elastic element as the elastic element and the trapped gas within the barrel <NUM> is expanded and/or subjected to vacuum by axial translation of the movable seal member <NUM> toward the first end <NUM>.

<FIG> illustrates a partial cross-sectional view of another example of the dampening element <NUM>. The dampening element <NUM> may be positioned and/or disposed between the first segment <NUM> of the fluid pathway and the second segment <NUM> of the fluid pathway. In some instances the dampening element <NUM> may be provided as a disposable tubing set with tubing extending from the dampening element <NUM> defining the first segment <NUM> and/or the second segment <NUM>, which may be removably engaged with the fluid pump <NUM> for moving fluid therethrough. Similar to other embodiments herein, the dampening element <NUM> may comprise one or more barrels <NUM>, each barrel <NUM> including the movable seal member <NUM> disposed within the barrel <NUM> (and/or a lumen defined by the barrel <NUM>), the biasing member <NUM> disposed within the barrel <NUM> (and/or the lumen defined by the barrel <NUM>) and engaged with the movable seal member <NUM>, and the cap <NUM> secured to the barrel <NUM> opposite the fluid pathway. The lumen of the barrel <NUM> may be a cylindrical lumen with the movable seal member <NUM> sealingly engaged with the cylindrical inner surface defining the lumen. The first end <NUM> of each of the one or more barrels <NUM> (and/or each of the lumens defined by the one or more barrels <NUM>) may include a port in fluid communication with the fluid pathway, and the cap <NUM> may be secured to the opposing second end <NUM> of the barrel <NUM> (and/or the lumen defined by the barrel <NUM>). The movable seal member <NUM> may be disposed within the barrel <NUM> (and/or the lumen defined by the barrel <NUM>) between the port leading to the fluid pathway and the cap <NUM>. The movable seal member <NUM> may be configured to sealingly engage an inner surface and/or an inner wall of the barrel <NUM>. In some embodiments, the movable seal member <NUM> may include at least one sealing element <NUM> extending around the perimeter of the movable seal member <NUM> and configured to sealingly engage the inner surface and/or the inner wall of the barrel <NUM>. For example, in some embodiments, the at least one sealing element <NUM> may include at least one O-ring (e.g., one O-ring, two O-rings, three O-rings, etc.) extending around the movable seal member <NUM> and configured to sealingly engage the inner surface and/or the inner wall of the barrel <NUM>.

The movable seal member <NUM> may be configured to translate axially within the one or more barrels <NUM> and/or within the lumen defined by the one or more barrels <NUM>. In some embodiments, using two or more sealing elements <NUM> may help to prevent tilting, cocking, and/or wedging of the movable seal member <NUM> within the barrel <NUM> and/or the lumen defined by the barrel <NUM>. The dampening element <NUM> may be configured to be responsive to pressure fluctuations of the pulsatile fluid flow to actively dampen the pressure fluctuations and smoothen the pulsatile fluid flow. In the example of <FIG>, the biasing member <NUM> may be a trapped gas within the barrel <NUM> and/or the lumen defined by the barrel <NUM>. In some embodiments, the trapped gas may be a compressed gas (i.e., a gas at a pressure greater than <NUM> psi) or a gas at atmospheric pressure (<NUM> psi), such as atmospheric air. In the example of <FIG>, the biasing member <NUM> (i.e., the trapped gas) may be disposed in within the barrel <NUM> between the movable seal member <NUM> and the cap <NUM>. In some embodiments the volume may be filled with atmospheric air during assembly and then trapped when the cap <NUM> is secured to the barrel <NUM>. Accordingly, the dampening element <NUM> may be configured to actively dampen pressure fluctuations of the pulsatile fluid flow in the distal direction (e.g., positive flow; during infusion). The biasing member <NUM> may bias and/or urge the movable seal member <NUM> toward and/or into an initial position proximate the first end <NUM>. The movable seal member <NUM>, in the initial position, may be at the first end <NUM> of the barrel <NUM> immediately adjacent to the port of the barrel <NUM> in fluid communication with the fluid pathway and/or the first segment <NUM> and/or the second segment <NUM>.

As fluid flow and/or pressure increases, fluid may flow into the barrel <NUM> through the port and apply a force against the movable seal member <NUM>, thereby urging the movable seal member <NUM> away from the fluid pathway and/or away from the initial position at the first end <NUM> and toward the second end <NUM> of the barrel <NUM>, and the biasing member <NUM> (i.e., the trapped gas) exerts a biasing force against the movable seal member <NUM>. For example, the compressed gas may be further compressed between the movable seal member <NUM> and the cap <NUM> as the volume of trapped air decreases to apply the biasing force, or the atmospheric air may increase in pressure greater than atmospheric pressure as the volume of trapped air decreases to apply the biasing force. This permits a portion of the fluid volume to be stored within the one or more barrels <NUM> of the dampening element <NUM> to compensate for the positive volume (+dv), which results in a reduced peak pressure and/or flow rate through the fluid pathway downstream of the dampening element <NUM>. The fluid volume that may be "stored" within the dampening element <NUM> may be calculated as the product of the cross-sectional area of the lumen of the barrel <NUM> and the axial displacement, length, or distance the movable seal member <NUM> is moved away from the initial position (e.g., dv = A * L). The relationship between the "stored" fluid volume (dv) and pressure change can be calculated using Boyle's law (Po*Vo) = (Pf*Vf), wherein Po = original pressure of compressed gas, Pf = final pressure of compressed gas, Vo = original volume of compressed gas, and Vf = final volume of compressed gas. The volume of stored fluid can be calculated using the equation: dv = Vo*(Pf-Po)/Pf.

In at least some embodiments wherein the biasing member <NUM> includes a trapped gas, the cap <NUM> may include a seal member rendering the portion of the barrel <NUM> and/or the lumen defined by the barrel <NUM> further defined by the side of the movable seal member <NUM> opposite the fluid pathway and/or the at least one sealing element <NUM> axially farthest away from the fluid pathway fluidtight, thereby permitting compression of the trapped gas therein as the fluid volume is stored in the dampening element <NUM>. The biasing force of the compressed gas trapped within the barrel <NUM> may be increased by axial translation of the movable seal member <NUM> toward the second end <NUM>, which reduces the volume of the trapped gas.

<FIG> illustrates a partial cross-sectional view of another example of the dampening element <NUM>. The dampening element <NUM> may be positioned and/or disposed between the first segment <NUM> of the fluid pathway and the second segment <NUM> of the fluid pathway. In some instances the dampening element <NUM> may be provided as a disposable tubing set with tubing extending from the dampening element <NUM> defining the first segment <NUM> and/or the second segment <NUM>, which may be removably engaged with the fluid pump <NUM> for moving fluid therethrough. Similar to other embodiments herein, the dampening element <NUM> may comprise one or more barrels <NUM>, each barrel <NUM> including the movable seal member <NUM> disposed within the barrel <NUM> (and/or the lumen defined by the barrel <NUM>), the biasing member <NUM> disposed within the barrel <NUM> (and/or the lumen defined by the barrel <NUM>) and engaged with the movable seal member <NUM>, and the cap <NUM> secured to the barrel <NUM> opposite the fluid pathway. The first end <NUM> of each of the one or more barrels <NUM> (and/or each of the lumens defined by the one or more barrels <NUM>) may include a port in fluid communication with the fluid pathway, and the cap <NUM> may be secured to the opposing second end <NUM> of the barrel <NUM> (and/or the lumen defined by the barrel <NUM>). The movable seal member <NUM> may be disposed within the barrel <NUM> (and/or the lumen defined by the barrel <NUM>) between the port leading to the fluid pathway and the cap <NUM>. The movable seal member <NUM> may be configured to sealingly engage the inner surface and/or the inner wall of the barrel <NUM>. The lumen of the barrel <NUM> may be a cylindrical lumen with the movable seal member <NUM> sealingly engaged with the cylindrical inner surface defining the lumen. In some embodiments, the movable seal member <NUM> may include at least one sealing element <NUM> extending around the perimeter of the movable seal member <NUM> and configured to sealingly engage the inner surface and/or the inner wall of the barrel <NUM>. For example, in some embodiments, the at least one sealing element <NUM> may include at least one O-ring (e.g., one O-ring, two O-rings, three O-rings, etc.) extending around the movable seal member <NUM> and configured to sealingly engage the inner surface and/or the inner wall of the barrel <NUM>.

The movable seal member <NUM> may be configured to translate axially within the one or more barrels <NUM> and/or within the lumen defined by the one or more barrels <NUM>. In some embodiments, using two or more sealing elements <NUM> may help to prevent tilting, cocking, and/or wedging of the movable seal member <NUM> within the barrel <NUM> and/or the lumen defined by the barrel <NUM>. The dampening element <NUM> may be configured to be responsive to pressure fluctuations of the pulsatile fluid flow to actively dampen the pressure fluctuations and smoothen the pulsatile fluid flow. In the example of <FIG>, the biasing member <NUM> may be a gas at atmospheric pressure (<NUM> psi), such as atmospheric air, or a vacuum or a partial vacuum trapped within the barrel <NUM> and/or the lumen defined by the barrel <NUM>. In the example of <FIG>, the biasing member <NUM> may be disposed within the barrel <NUM> between the movable seal member <NUM> and the cap <NUM>. In some embodiments the volume may be filled with atmospheric air during assembly and then trapped when the cap <NUM> is secured to the barrel <NUM>. Accordingly, the dampening element <NUM> may be configured to actively dampen pressure fluctuations of the pulsatile fluid flow in the proximal direction (e.g., negative flow; during suction). The biasing member <NUM> may bias and/or urge the movable seal member <NUM> toward and/or into an initial position proximate the second end <NUM> or otherwise position the movable seal member <NUM> toward the second end <NUM>. The movable seal member <NUM>, in the initial position, may be at the second end <NUM> of the barrel <NUM> immediately adjacent to and/or in contact with the cap <NUM>.

During pulsatile fluid flow in the distal direction (e.g., positive flow; during infusion) and/or during periods of low flow and low suction in the proximal direction (e.g., negative flow; during suction), fluid may flow into the barrel <NUM> and/or the lumen defined by the barrel <NUM> between the first end <NUM> and the movable seal member <NUM>. The volume of gas forming the biasing element <NUM> generates a biasing force (i.e. vacuum or partial vacuum) as the movable seal member <NUM> is pulled toward the port leading to the fluid pathway. As the suction or negative pressure increases in magnitude to a point where the suctioning force exceeds the biasing force of the biasing member <NUM>, fluid may be drawn out of the barrel <NUM>, thereby "pulling" the movable seal member <NUM> away from the cap <NUM> and/or away from the initial position at the second end <NUM> and toward the first end <NUM> of the barrel <NUM>. This permits a portion of the fluid volume to be released from the one or more barrels <NUM> of the dampening element <NUM> to compensate for the negative volume (-dv), which results in a smoothened pressure and/or flow rate through the fluid pathway.

In at least some embodiments wherein the biasing member <NUM> includes a gas at atmospheric pressure or the vacuum or the partial vacuum, the cap <NUM> may include a seal member rendering the portion of the barrel <NUM> and/or the lumen defined by the barrel <NUM> further defined by the side of the movable seal member <NUM> opposite the fluid pathway and/or the at least one sealing element <NUM> axially farthest away from the fluid pathway fluidtight, and the biasing force of the vacuum or partial vacuum trapped within the barrel <NUM> may be increased by axial translation of the movable seal member <NUM> toward the first end <NUM>.

<FIG> illustrates a partial cross-sectional view of one example of the dampening element <NUM> that effectively combines the examples of <FIG> and <FIG>. The dampening element <NUM> may be positioned and/or disposed between the first segment <NUM> of the fluid pathway and the second segment <NUM> of the fluid pathway such that the dampening element <NUM> is in fluid communication with the fluid pathway. Similar to other embodiments described herein, the dampening element <NUM> may comprise one or more barrels <NUM>, each barrel <NUM> including the movable seal member <NUM> disposed within the barrel <NUM> (and/or a lumen defined by the barrel <NUM>), the biasing member <NUM> disposed within the barrel <NUM> (and/or the lumen defined by the barrel <NUM>) and engaged with the movable seal member <NUM>, and the cap <NUM> secured to the barrel <NUM> opposite the fluid pathway. The first end <NUM> of each of the one or more barrels <NUM> (and/or each of the lumens defined by the one or more barrels <NUM>) may include a port in fluid communication with the fluid pathway, and the cap <NUM> may be secured to the opposing second end <NUM> of the barrel <NUM> (and/or the lumen defined by the barrel <NUM>). The movable seal member <NUM> may be disposed within the barrel <NUM> (and/or the lumen defined by the barrel <NUM>) between the fluid pathway and the cap <NUM>. The movable seal member <NUM> may be configured to sealingly engage an inner surface and/or an inner wall of the barrel <NUM>. The lumen of the barrel <NUM> may be a cylindrical lumen with the movable seal member <NUM> sealingly engaged with the cylindrical inner surface defining the lumen. In some embodiments, the movable seal member <NUM> may include at least one sealing element <NUM> extending around the perimeter of the movable seal member <NUM> and configured to sealingly engage the inner surface and/or the inner wall of the barrel <NUM>. For example, in some embodiments, the at least one sealing element <NUM> may include at least one O-ring (e.g., one O-ring, two O-rings, three O-rings, etc.) extending around the movable seal member <NUM> and configured to sealingly engage the inner surface and/or the inner wall of the barrel <NUM>.

The movable seal member <NUM> may be configured to translate axially within the one or more barrels <NUM> and/or within the lumen defined by the one or more barrels <NUM>. In some embodiments, using two or more sealing elements <NUM> may help to prevent tilting, cocking, and/or wedging of the movable seal member <NUM> within the barrel <NUM> and/or the lumen defined by the barrel <NUM>. The dampening element <NUM> may be configured to be responsive to pressure fluctuations of the pulsatile fluid flow to actively dampen the pressure fluctuations and smoothen the pulsatile fluid flow. In the example of <FIG>, the biasing member <NUM> may be a trapped gas occupying a volume of space within the barrel <NUM> and/or the lumen defined by the barrel <NUM> at equilibrium, such as at atmospheric pressure (<NUM>. <NUM> psi). In some embodiments the volume may be filled with atmospheric air during assembly and then trapped when the cap <NUM> is secured to the barrel <NUM>. In the example of <FIG>, the volume of trapped gas forming the biasing member <NUM> may be disposed in within the barrel <NUM> between the movable seal member <NUM> and the cap <NUM>. Accordingly, the dampening element <NUM> may be configured to actively dampen pressure fluctuations of the pulsatile fluid flow in the distal direction (e.g., positive flow; during infusion), in the proximal direction (e.g., negative flow; during suction), and/or in both flow directions during operation of the pump. The movable seal member <NUM> may translate axially within the barrel <NUM> in either direction, depending on whether the system is experiencing positive pressure and/or flow spikes or negative pressure and/or flow spikes. As the movable seal member <NUM> translates axially within the barrel <NUM>, the characteristics of the biasing member <NUM> and/or the trapped gas within the barrel <NUM> may be altered, resulting in compression of the trapped gas (as a consequence of decreasing the volume of trapped gas) or generating a vacuum or partial vacuum as a consequence of increasing the volume of trapped gas. For example, as the movable seal member <NUM> is displaced or translates axially toward the second end <NUM>, the trapped gas is compressed, thereby generating a biasing force urging the movable seal member <NUM> towards the first end <NUM> and/or the initial position, and as the movable seal member <NUM> is displaced or translates axially toward the first end <NUM>, the trapped gas is expanded and/or subjected to a vacuum or partial vacuum, thereby generating a biasing force urging the movable seal member <NUM> towards the second end <NUM> and/or the initial position.

As the fluid flow and/or pressure increases, fluid may flow into the barrel <NUM> through the port and apply a force against the movable seal member <NUM>, thereby urging the movable seal member <NUM> away from the fluid pathway and/or away from the initial, equilibrium position (intermediate the first end <NUM> and the second end <NUM>) and toward the second end <NUM> of the barrel <NUM>, and the biasing member <NUM> (i.e., the gas) may be compressed between the movable seal member <NUM> and the cap <NUM> exerting a biasing force against the movable seal member <NUM>. This permits a portion of the fluid volume to be stored within the one or more barrels <NUM> of the dampening element <NUM> to compensate for the positive volume (+dv), which results in a reduced peak pressure and/or flow rate through the fluid pathway downstream of the dampening element <NUM>. The fluid volume that may be "stored" within the dampening element <NUM> may be calculated as the product of the cross-sectional area of the lumen of the barrel <NUM> and the axial displacement, length, or distance the movable seal member <NUM> is moved away from the initial position (e.g., dv = A * L). The relationship between the "stored" fluid volume (dv) and pressure change can be calculated using Boyle's law (Po*Vo) = (Pf*Vf), wherein Po = original pressure of compressed gas, Pf = final pressure of compressed gas, Vo = original volume of compressed gas, and Vf = final volume of compressed gas. The volume of stored fluid can be calculated using the equation: dv = Vo*(Pf-Po)/Pf.

As the suction and/or the negative pressure increases in magnitude with fluid flow in the proximal direction, fluid may be suctioned out of the barrel <NUM>, thereby "pulling" the movable seal member <NUM> away from the cap <NUM> and/or away from the initial position and toward the first end <NUM> of the barrel <NUM>. This permits a portion of the fluid volume to be released from the one or more barrels <NUM> of the dampening element <NUM> to compensate for the negative volume (-dv), which results in an increased minimum pressure and/or flow rate through the fluid pathway. The biasing force of the vacuum or partial vacuum trapped within the barrel <NUM> may be increased by axial translation of the movable seal member <NUM> toward the first end <NUM>.

<FIG> illustrates a partial cross-sectional view of one example of the dampening element <NUM>. The dampening element <NUM> may be positioned and/or disposed between the first segment <NUM> of the fluid pathway and the second segment <NUM> of the fluid pathway such that the dampening element <NUM> is in fluid communication with the fluid pathway. Similar to other embodiments described herein, the dampening element <NUM> may comprise one or more barrels <NUM>, each barrel <NUM> including a movable seal member <NUM> disposed within the barrel <NUM> (and/or a lumen defined by the barrel <NUM>), a biasing member <NUM> disposed within the barrel <NUM> (and/or the lumen defined by the barrel <NUM>) and engaged with the movable seal member <NUM>, and a cap <NUM> secured to the barrel <NUM> opposite the fluid pathway. The first end <NUM> of each of the one or more barrels <NUM> (and/or each of the lumens defined by the one or more barrels <NUM>) may include a port in fluid communication with the fluid pathway, and the cap <NUM> may be secured to an opposing second end <NUM> of the barrel <NUM> (and/or the lumen defined by the barrel <NUM>). The movable seal member <NUM> may be disposed within the barrel <NUM> (and/or the lumen defined by the barrel <NUM>) between the fluid pathway and the cap <NUM>. The movable seal member <NUM> may be configured to sealingly engage an inner surface and/or an inner wall of the barrel <NUM>. The lumen of the barrel <NUM> may be a cylindrical lumen with the movable seal member <NUM> sealingly engaged with the cylindrical inner surface defining the lumen. In some embodiments, the movable seal member <NUM> may include at least one sealing element <NUM> extending around a perimeter of the movable seal member <NUM> and configured to sealingly engage the inner surface and/or the inner wall of the barrel <NUM>. For example, in some embodiments, the at least one sealing element <NUM> may include at least one O-ring (e.g., one O-ring, two O-rings, three O-rings, etc.) extending around the movable seal member <NUM> and configured to sealingly engage the inner surface and/or the inner wall of the barrel <NUM>.

The movable seal member <NUM> may be configured to translate axially within the one or more barrels <NUM> and/or within the lumen defined by the one or more barrels <NUM>. In some embodiments, using two or more sealing elements <NUM> may help to prevent tilting, cocking, and/or wedging of the movable seal member <NUM> within the barrel <NUM> and/or the lumen defined by the barrel <NUM>. The dampening element <NUM> may be configured to be responsive to pressure fluctuations of the pulsatile fluid flow to actively dampen the pressure fluctuations and smoothen the pulsatile fluid flow. In the example of <FIG>, the biasing member <NUM> may be an elastic element that is axially compressible and axially extendable. In some embodiments, the elastic element may be a spring, an expandable/compressible member, or other similar structure or element. In the example of <FIG>, the spring may be secured in equilibrium within the barrel <NUM> between the movable seal member <NUM> and the first end <NUM> of the barrel <NUM>. Additionally, in some embodiments, the dampening element <NUM> may include a second biasing member. The second biasing member may be a trapped gas disposed between the movable seal member <NUM> and the cap <NUM> at equilibrium. In some embodiments, the second biasing member may be compressed gas acting against the spring. Accordingly, the dampening element <NUM> may be configured to actively dampen pressure fluctuations of the pulsatile fluid flow in the proximal direction (e.g., negative flow; during suction) and the distal direction (e.g., positive flow; during infusion). The biasing member <NUM> and/or the second biasing member may position the movable seal member <NUM> at an initial, equilibrium position intermediate the first end <NUM> and the second end <NUM> of the barrel <NUM>. In some embodiments, when the movable seal member <NUM> is at the initial position, the biasing member <NUM> may be in equilibrium, but able to axially compress and axially elongate when subjected to a force acting on the movable seal member <NUM> that moves the movable seal member <NUM> within the barrel <NUM>. As the movable seal member <NUM> translates axially toward the second end <NUM>, the spring may be stretched in tension, generating a biasing force biasing the movable seal member <NUM> towards the initial position. As the movable seal member <NUM> translates axially toward the first end <NUM>, the spring may be compressed in compression generating a biasing force biasing the movable seal member <NUM> towards the initial position.

As the fluid flow and/or pressure increases, fluid may flow into the barrel <NUM> through the port and apply a force against the movable seal member <NUM>, thereby urging the movable seal member <NUM> away from the fluid pathway and/or away from the initial, equilibrium position (intermediate the first end <NUM> and the second end <NUM>) and toward the second end <NUM> of the barrel <NUM>. This permits a portion of the fluid volume to be stored within the one or more barrels <NUM> of the dampening element <NUM> to compensate for the positive volume (+dv), which results in a reduced peak pressure and/or flow rate through the fluid pathway downstream of the dampening element <NUM>. The fluid volume that may be "stored" within the dampening element <NUM> may be calculated as the product of the cross-sectional area of the lumen of the barrel <NUM> and the axial displacement, length, or distance the movable seal member <NUM> is moved away from the initial position (e.g., dv = A * L). The biasing force exerted by the elastic element (e.g., the biasing member <NUM>) may be calculated using Hooke's law (e.g., F = -kx; where k is the rate or spring constant and x is the displacement length of the elastic element from its equilibrium position).

As the suction and/or the negative pressure increases in magnitude with fluid flow in the proximal direction, fluid may be suctioned out of the barrel <NUM>, thereby "pulling" the movable seal member <NUM> away from the initial position and toward the first end <NUM> of the barrel <NUM>. This permits a portion of the fluid volume to be released from the one or more barrels <NUM> of the dampening element <NUM> to compensate for the negative volume (-dv), which results in an increased minimum pressure and/or flow rate through the fluid pathway.

<FIG> illustrates a partial cross-sectional view of another example of the dampening element <NUM> similar to the embodiment of <FIG>, except the biasing member <NUM> (e.g., spring) is arranged between the movable seal member <NUM> and the cap <NUM> of the barrel <NUM>. In the example of <FIG>, the spring may be secured in equilibrium within the barrel <NUM> between the movable seal member <NUM> and the second end <NUM> of the barrel <NUM>. Accordingly, the dampening element <NUM> may be configured to actively dampen pressure fluctuations of the pulsatile fluid flow in the proximal direction (e.g., negative flow; during suction) and the distal direction (e.g., positive flow; during infusion). The biasing member <NUM> may position the movable seal member <NUM> at an initial, equilibrium position intermediate the first end <NUM> and the second end <NUM> of the barrel <NUM>. In some embodiments, when the movable seal member <NUM> is at the initial position, the biasing member <NUM> may be in equilibrium, but able to axially compress and axially elongate when subjected to a force acting on the movable seal member <NUM> that moves the movable seal member <NUM> within the barrel <NUM>. As the movable seal member <NUM> translates axially toward the first end <NUM>, the spring may be stretched in tension, generating a biasing force biasing the movable seal member <NUM> towards the initial position. As the movable seal member <NUM> translates axially toward the second end <NUM>, the spring may be compressed in compression generating a biasing force biasing the movable seal member <NUM> towards the initial position.

<FIG> illustrates a partial cross-sectional view of another example of the dampening element <NUM>. The example illustrated in <FIG> is substantially the same as that illustrated in <FIG>, with an additional feature added. However, it will be appreciated that the additional feature of <FIG> may work equally well in any and/or all embodiments and/or examples of the dampening element <NUM> disclosed herein - including, but not limited to, the examples of <FIG>. Likewise, the additional feature of <FIG> may be included in any and/or all of the examples that follow <FIG>. The dampening element <NUM> illustrated in <FIG> further includes a pressure relief port <NUM> in fluid communication with the barrel <NUM> and/or the lumen defined by the barrel <NUM>. As may be appreciated, the pressure relief port <NUM> may be opened or closed when the fluid pressure within the barrel <NUM> and/or the lumen defined by the barrel <NUM> exceeds a pressure threshold.

In the example of <FIG>, the biasing member <NUM> may be positioned within the barrel <NUM> between the movable seal member <NUM> and the cap <NUM>. Accordingly, the dampening element <NUM> may be configured to actively dampen pressure fluctuations of the pulsatile fluid flow in the distal direction (e.g., positive flow; during infusion). The biasing member <NUM> may bias and/or urge the movable seal member <NUM> toward and/or into the initial position proximate the first end <NUM>. In the initial position, and/or during any axial translation of the movable seal member <NUM>, the at least one sealing element <NUM> disposed closest to the second end <NUM> of the barrel <NUM> may form a fluidtight seal between the pressure relief port <NUM> and the cap <NUM> (and/or the second end <NUM> of the barrel <NUM>). For example, the pressure relief port <NUM> and/or the fluid pathway may be fluidly and completely sealed off from the second end <NUM> of the barrel <NUM> and/or the cap <NUM>. In some embodiments, the at least one sealing element <NUM> disposed closest to the second end <NUM> of the barrel <NUM> may always be disposed between the pressure relief port <NUM> and the second end <NUM> of the barrel <NUM> and/or the cap <NUM>, and the at least one sealing element <NUM> disposed closest to the first end <NUM> of the barrel <NUM> may be disposed between the pressure relief port <NUM> and the first end <NUM> of the barrel <NUM>, except when a fluid pressure exceeding the pressure threshold causes axial translation of the movable seal member <NUM> toward the second end <NUM> of the barrel <NUM> a sufficient distance to place the fluid in the fluid pathway in fluid communication with the pressure relief port <NUM>.

As the fluid flow and/or pressure increases, fluid may flow into the barrel <NUM> from the fluid pathway and apply a force against the movable seal member <NUM>, thereby urging the movable seal member <NUM> away from the fluid pathway and/or away from the initial, equilibrium position at the first end <NUM> and toward the second end <NUM> of the barrel <NUM>, and the biasing member <NUM> may be compressed. This permits a portion of the fluid volume to be stored within the one or more barrels <NUM> of the dampening element <NUM> to compensate for the positive volume (+dv), which results in a reduced peak pressure and/or flow rate through the fluid pathway downstream of the dampening element <NUM>. Additionally, as the movable seal member <NUM> translates toward the cap <NUM> and/or the second end <NUM> of the barrel <NUM>, the end of the movable seal member <NUM> (and/or the at least one sealing element <NUM>) closest to the first end <NUM> may translate axially past the pressure relief port <NUM> when the fluid exceeds a threshold pressure level, thereby placing the fluid in fluid communication with the pressure relief port <NUM>. The pressure relief port <NUM> may include a pressure relief valve that may open at a threshold pressure (which may be less than, equal to, or greater than the threshold pressure necessary to move the movable seal member <NUM> sufficiently to place the fluid in fluid communication with the pressure relief port <NUM>) and permitting a portion of the fluid flowing into the barrel <NUM> to flow out of the pressure relief port <NUM>. As the fluid pressure and/or flow is reduced below the threshold, the movable seal member <NUM> translates toward the first end <NUM> of the barrel <NUM>, and the end of the movable seal member <NUM> (and/or the at least one sealing element <NUM>) closest to the first end <NUM> may translate axially past the pressure relief port <NUM>, thereby closing the pressure relief port <NUM> and isolating the fluid in the fluid pathway from the pressure relief port <NUM>.

<FIG> illustrates a partial cross-sectional view of another example of the dampening element <NUM>. The example illustrated in <FIG> is substantially the same as that illustrated in <FIG>, with an additional feature added. However, it will be appreciated that the additional feature of <FIG> may work equally well in any and/or all embodiments and/or examples of the dampening element <NUM> disclosed herein - including, but not limited to, the examples of <FIG>. Likewise, the additional feature of <FIG> may be included in any and/or all of the examples that follow <FIG>. The dampening element <NUM> illustrated in <FIG> further includes an adjustment mechanism, such as an adjustable cap <NUM> for adjusting the biasing force and/or amount of translation of the movable seal member <NUM> permitted. In some embodiments, each of the one or more barrels <NUM> may include an adjustable cap <NUM>. In some configurations, one or more barrels <NUM> may include an adjustable cap <NUM>, and one or more barrels <NUM> may include the non-adjustable cap <NUM> (not shown in <FIG>), in varying combination(s). As may be appreciated, the adjustable cap <NUM> may be configured to adjust a working length of the barrel <NUM> and/or the biasing force of the biasing member <NUM>. In at least some embodiments, some and/or each adjustable cap <NUM> may be configured to threadably engage its respective barrel <NUM>, wherein rotation of the adjustable cap <NUM> relative to the barrel <NUM> translates the adjustable cap <NUM> axially to adjust the working length of the barrel <NUM> and/or the biasing force of the biasing member <NUM>. Alternatively, in some embodiments, the adjustable cap <NUM> may be configured to engage its respective barrel <NUM> using a camming mechanism, or other suitable engagement means. As may be appreciated, translating the adjustable cap <NUM> towards the first end <NUM> of the barrel <NUM> may further compress the biasing member <NUM>, may increase the bias toward the first end of the barrel <NUM>, and/or may increase the bias force applied to the movable seal member <NUM> by the biasing member <NUM> at an initial position. Similarly, translating the adjustable cap <NUM> away from the first end <NUM> of the barrel <NUM> and/or towards the second end <NUM> of the barrel <NUM> may decompress the biasing member <NUM>, may decrease the bias toward the first end of the barrel <NUM>, and/or may decrease the bias force applied to the movable seal member <NUM> by the biasing member <NUM> at an initial position. Thus, a user may adjust the adjustment cap <NUM>, or other adjustment mechanism, to provide a desired responsiveness of the dampening element <NUM> to pressure and/or flow fluctuations during a medical procedure.

<FIG> illustrates a partial cross-sectional view of another example of the dampening element <NUM>. The example illustrated in <FIG> is substantially the same as that illustrated in <FIG>, with an additional feature added. However, it will be appreciated that the additional feature of <FIG> may work equally well in any and/or all embodiments and/or examples of the dampening element <NUM> disclosed herein - including, but not limited to, the examples of <FIG>. Likewise, the additional feature of <FIG> may be included in any and/or all of the examples that follow <FIG>. The dampening element <NUM> illustrated in <FIG> further includes an adjustment mechanism, such as an adjustable cap <NUM> for adjusting the biasing force and/or amount of translation of the movable seal member <NUM> permitted. In some embodiments, each of the one or more barrels <NUM> may include an adjustable cap <NUM>. In some configurations, one or more barrels <NUM> may include an adjustable cap <NUM>, and one or more barrels <NUM> may include the non-adjustable cap <NUM> (not shown in <FIG>), in varying combination(s). As may be appreciated, the adjustable cap <NUM> may be configured to adjust a working length of the barrel <NUM> and thus the volume of the trapped gas in the initial position. In at least some embodiments, some and/or each adjustable cap <NUM> may be configured to threadably engage its respective barrel <NUM>, wherein rotation of the adjustable cap <NUM> relative to the barrel <NUM> translates the adjustable cap <NUM> axially to adjust the working length of the barrel <NUM> and thus the volume of the trapped gas in the initial position. Alternatively, in some embodiments, the adjustable cap <NUM> may be configured to engage its respective barrel <NUM> using a camming mechanism, or other suitable engagement means. As may be appreciated, translating the adjustable cap <NUM> towards the first end <NUM> of the barrel <NUM> may further compress the biasing member <NUM> (e.g., the trapped gas), may increase the bias toward the first end of the barrel <NUM>, and/or may increase the bias force applied to the movable seal member <NUM> by the biasing member <NUM>. For example, translating the adjustable cap <NUM> towards the first end <NUM> of the barrel <NUM> may reduce the volume and thus compress and increase the pressure of the trapped gas within the barrel <NUM>. Similarly, translating the adjustable cap <NUM> away from the first end <NUM> of the barrel <NUM> and/or towards the second end <NUM> of the barrel <NUM> may increase the volume and thus decompress the biasing member <NUM> (e.g., the trapped gas), may decrease the bias toward the first end of the barrel <NUM>, and/or may decrease the bias force applied to the movable seal member <NUM> by the biasing member <NUM>. For example, translating the adjustable cap <NUM> towards the second end <NUM> of the barrel <NUM> may decompress and decrease the pressure of the trapped gas within the barrel <NUM>. Alternatively and/or additionally, the adjustable cap <NUM> may be used in embodiments and/or examples where the biasing member <NUM> is a vacuum or partial vacuum disposed and/or trapped within the barrel <NUM>.

<FIG> illustrates a partial cross-sectional view of another example of the dampening element <NUM>. The example illustrated in <FIG> combines selected features of the examples illustrated in <FIG> and <FIG>. However, it will be appreciated that the example of <FIG> may work equally well in and/or with features from any and/or all embodiments and/or examples of the dampening element <NUM> disclosed herein. Similarly, additional arrangements and/or combinations of features are also contemplated.

The dampening element <NUM> may be positioned and/or disposed between the first segment <NUM> of the fluid pathway and the second segment <NUM> of the fluid pathway. The dampening element <NUM> may be in fluid communication with the fluid pathway, and in some instances the dampening element <NUM> may be provided as a disposable tubing set with tubing extending from the dampening element <NUM> defining the first segment <NUM> and/or the second segment <NUM>, which may be removably engaged with the fluid pump <NUM> for moving fluid therethrough. The dampening element <NUM> may comprise a plurality of barrels <NUM>, each barrel <NUM> including a movable seal member <NUM> disposed within the barrel <NUM> (and/or a lumen defined by the barrel <NUM>), a biasing member <NUM> disposed within the barrel <NUM> (and/or the lumen defined by the barrel <NUM>) and engaged with the movable seal member <NUM>, and a cap <NUM> (not shown in <FIG>) secured to the barrel <NUM> opposite the fluid pathway. The cap <NUM> may be selectively lockable onto the barrel <NUM>. Alternatively, some of and/or each barrel <NUM> may comprise an adjustable cap <NUM> as described herein.

In the example illustrated in <FIG>, the plurality of barrels <NUM> may include and/or comprise a first barrel <NUM> and a second barrel <NUM>. In at least some embodiments, the first barrel <NUM> and the second barrel <NUM> are both positioned between the fluid pump <NUM> and the fluid flow sensor <NUM> and/or the medical device <NUM>. Other arrangements and/or configurations, including but not limited to three barrels, four barrels, five barrels, or more barrels, are also contemplated. The first barrel <NUM> may include a first movable seal member <NUM> disposed within the first barrel <NUM> (and/or the lumen defined by the first barrel <NUM>) and a first biasing member <NUM> disposed within the first barrel <NUM> (and/or the lumen defined by the first barrel <NUM>) and engaged with the first movable seal member <NUM>. The second barrel <NUM> may include a second movable seal member <NUM> disposed within the second barrel <NUM> (and/or the lumen defined by the second barrel <NUM>) and a second biasing member <NUM> disposed within the second barrel <NUM> (and/or the lumen defined by the second barrel <NUM>) and engaged with the second movable seal member <NUM>. In some embodiments, the first barrel <NUM> and the second barrel <NUM> may be formed as a unified housing. In some embodiments, the first barrel <NUM> may be structurally and/or functionally independent of the second barrel <NUM>. As such, multiple first barrels and/or multiple second barrels may be utilized and/or included within the dampening element <NUM>. In some embodiments, the fluid volume(s) desired to be accommodated by the one or more barrels <NUM> may be divided into several barrels placed in series with each other, thereby providing an additive configuration capable of accommodating a greater volume of fluid and/or a higher pressure pulse.

In should be noted that the orientation and positioning of the first barrel <NUM> and the second barrel <NUM> relative to each other and/or relative to the fluid pathway may be varied while maintaining the desired function(s) and/or benefits of the dampening element <NUM>. In the view illustrated, the first barrel <NUM> and the second barrel <NUM> both extend upward from the fluid pathway and/or the first segment <NUM> and the second segment <NUM>. In some embodiments, one of the first barrel <NUM> or the second barrel <NUM> may extend upward from the fluid pathway and/or the first segment <NUM> and the second segment <NUM> and the other of the first barrel <NUM> or the second barrel <NUM> may extend downward from the fluid pathway and/or the first segment <NUM> and the second segment <NUM>. Alternatively, one of the first barrel <NUM> or the second barrel <NUM> may extend at a non-zero angle (e.g., <NUM> degrees, <NUM> degrees, <NUM> degrees, <NUM> degrees, <NUM> degrees, <NUM> degrees, etc.) relative to the other of the first barrel <NUM> or the second barrel <NUM>. Other arrangements and/or configurations are also contemplated. For example, in some embodiments, positioning of the first barrel <NUM> and the second barrel <NUM> may be interchanged while retaining their respective functions. In some embodiments, the dampening element <NUM>, the first barrel <NUM>, and/or the second barrel <NUM> may be positioned in any orientation relative to the fluid pathway and/or the first segment <NUM> and the second segment <NUM> while retaining its respective function(s). For example, the dampening element <NUM>, the first barrel <NUM>, and/or the second barrel <NUM> may be positioned on its side, upside down, etc. This arrangement is equally applicable to all other embodiments described and contemplated within the context of this application.

The example illustrated in <FIG> includes adjustable caps <NUM>, but this is not intended to be limiting, and the cap <NUM> and/or the adjustable cap <NUM> may be used in varying combinations as described herein. Additionally, as mentioned above, in some embodiments, the dampening element <NUM> may include the first connector <NUM> and/or the second connector <NUM> and/or multiples thereof.

In some embodiments, a first end <NUM> of each of the one or more barrels <NUM> (and/or each of the lumens defined by the one or more barrels <NUM>) may include a port in fluid communication with the fluid pathway, and the cap <NUM> and/or the adjustable cap <NUM> may be secured to an opposing second end <NUM> of the barrel <NUM> (and/or the lumen defined by the barrel <NUM>). The movable seal member <NUM> may be disposed within the barrel <NUM> (and/or the lumen defined by the barrel <NUM>) between the port leading to the fluid pathway and the cap <NUM> and/or the adjustable cap <NUM>. The movable seal member <NUM> may be configured to sealingly engage an inner surface and/or an inner wall of the barrel <NUM>. In some embodiments, the movable seal member <NUM> may include at least one sealing element <NUM> extending around a perimeter of the movable seal member <NUM> and configured to sealingly engage the inner surface and/or the inner wall of the barrel <NUM>. For example, in some embodiments, the at least one sealing element <NUM> may include at least one O-ring (e.g., one O-ring, two O-rings, three O-rings, etc.) extending around the movable seal member <NUM> and configured to sealingly engage the inner surface and/or the inner wall of the barrel <NUM>.

The movable seal member <NUM> may be configured to translate axially within the one or more barrels <NUM> and/or within the lumen defined by the one or more barrels <NUM>. In some embodiments, using two or more sealing elements <NUM> may help to prevent tilting, cocking, and/or wedging of the movable seal member <NUM> within the barrel <NUM> and/or the lumen defined by the barrel <NUM>. The dampening element <NUM> may be configured to be responsive to pressure fluctuations of the pulsatile fluid flow to actively dampen the pressure fluctuations and smoothen the pulsatile fluid flow.

In the example of <FIG>, the first biasing member <NUM> (e.g., spring) may be secured in compression or equilibrium within the first barrel <NUM> between the first movable seal member <NUM> and the cap <NUM> and/or the adjustable cap <NUM>. Accordingly, the dampening element <NUM> and/or the first barrel <NUM> may be configured to actively dampen pressure fluctuations of the pulsatile fluid flow in the distal direction (e.g., positive flow; during infusion). The first biasing member <NUM> may bias and/or urge the first movable seal member <NUM> toward and/or into an initial position proximate the first end <NUM> or otherwise position the movable seal member <NUM> toward the first end <NUM>. The first movable seal member <NUM>, in the initial position, may be at the first end <NUM> of the first barrel <NUM> immediately adjacent to the port of the first barrel <NUM> in fluid communication with the fluid pathway and/or the first segment <NUM> and/or the second segment <NUM>. The first dampening element <NUM> may function similar to the dampening element <NUM> of <FIG> to be responsive to pressure fluctuations of the pulsatile fluid flow in a distal direction (e.g., positive pressure) to actively dampen the pressure fluctuations and smoothen the pulsatile fluid flow.

Furthermore, the second biasing member <NUM> (e.g., spring) may be secured in compression or equilibrium within the second barrel <NUM> between the second movable seal member <NUM> and the first end <NUM> of the second barrel <NUM>. Accordingly, the dampening element <NUM> and/or the second barrel <NUM> may be configured to actively dampen pressure fluctuations of the pulsatile fluid flow in the proximal direction (e.g., negative flow; during suction). The second biasing member <NUM> may bias and/or urge the second movable seal member <NUM> toward and/or into an initial position proximate the second end <NUM> or otherwise position the movable seal member <NUM> toward the second end <NUM>. The second movable seal member <NUM>, in the initial position, may be at the second end <NUM> of the second barrel <NUM> immediately adjacent to and/or in contact with the cap <NUM> and/or the adjustable cap <NUM>. The second dampening element <NUM> may function similar to the dampening element <NUM> of <FIG> to be responsive to pressure fluctuations of the pulsatile fluid flow in a proximal direction (e.g., negative pressure) to actively dampen the pressure fluctuations and smoothen the pulsatile fluid flow.

In addition or alternatively, the dampening element <NUM> may be constructed with more than one barrel configured as the first barrel or as the second barrel. For example, the dampening element <NUM> may be configured with two or more "first" barrels each configured to actively dampen pressure fluctuations of the pulsatile fluid flow in the distal direction (e.g., positive flow; during infusion). Each of the "first" barrels may be configured with a different biasing force (e.g., spring constant, etc.) to provide a desired responsiveness to the pulsatile fluid flow. Additionally or alternatively, the dampening element <NUM> may be configured with two or more "second" barrels each configured to actively dampen pressure fluctuations of the pulsatile fluid flow in the proximal direction (e.g., negative flow; during suction). Each of the "second" barrels may be configured with a different biasing force (e.g., spring constant, etc.) to provide a desired responsiveness to the pulsatile fluid flow. Varying combinations of multiple barrels are also contemplated.

In should be noted that the orientation of the first barrel <NUM> and the second barrel <NUM> relative to each other and/or relative to the fluid pathway may be varied while maintaining the desired function(s) and/or benefits of the dampening element <NUM>. In the view illustrated, the first barrel <NUM> and the second barrel <NUM> both extend upward from the fluid pathway and/or the first segment <NUM> and the second segment <NUM>. In some embodiments, one of the first barrel <NUM> or the second barrel <NUM> may extend upward from the fluid pathway and/or the first segment <NUM> and the second segment <NUM> and the other of the first barrel <NUM> or the second barrel <NUM> may extend downward from the fluid pathway and/or the first segment <NUM> and the second segment <NUM>. Alternatively, one of the first barrel <NUM> or the second barrel <NUM> may extend at a non-zero angle (e.g., <NUM> degrees, <NUM> degrees, <NUM> degrees, <NUM> degrees, <NUM> degrees, <NUM> degrees, etc.) relative to the other of the first barrel <NUM> or the second barrel <NUM>. Other arrangements and/or configurations are also contemplated. For example, in some embodiments, positioning of the first barrel <NUM> and the second barrel <NUM> may be interchanged while retaining their respective functions. In some embodiments, the dampening element <NUM>, the first barrel <NUM>, and/or the second barrel <NUM> may be positioned in any orientation relative to the fluid pathway and/or the first segment <NUM> and the second segment <NUM> while retaining its respective function(s). For example, the dampening element <NUM>, the first barrel <NUM>, and/or the second barrel <NUM> may be positioned on its side, upside down, etc. This arrangement is equally applicable to all other embodiments described and contemplated within the context of this application.

The movable seal member <NUM> may be configured to translate axially within the one or more barrels <NUM> and/or within the lumen defined by the one or more barrels <NUM>. In some embodiments, using two or more sealing elements <NUM> may help to prevent tilting, cocking, and/or wedging of the movable seal member <NUM> within the barrel <NUM> and/or the lumen defined by the barrel <NUM>. The dampening element <NUM> may be configured to be responsive to pressure fluctuations of the pulsatile fluid flow to actively dampen the pressure fluctuations and smoothen the pulsatile fluid flow. In the example of <FIG>, the biasing member <NUM> may be a trapped gas and/or a vacuum or partial vacuum trapped within the barrel <NUM> and/or the lumen defined by the barrel <NUM>. In some embodiments, the trapped gas may be a compressed gas (i.e., a gas at a pressure greater than <NUM> psi) or a gas at atmospheric pressure (<NUM> psi), such as atmospheric air. In the example of <FIG>, the biasing member <NUM> (i.e., the trapped gas) may be disposed in within the barrel <NUM> between the movable seal member <NUM> and the cap <NUM>.

Accordingly, the dampening element <NUM> may be configured to actively dampen pressure fluctuations of the pulsatile fluid flow in the distal direction (e.g., positive flow; during infusion). The first biasing member <NUM> may bias and/or urge the first movable seal member <NUM> toward and/or into an initial position proximate the first end <NUM>. The first movable seal member <NUM>, in the initial position, may be at the first end <NUM> of the barrel <NUM> immediately adjacent to the port of the first barrel <NUM> in fluid communication with the fluid pathway and/or the first segment <NUM> and/or the second segment <NUM>. The first dampening element <NUM> may function similar to the dampening element <NUM> of <FIG> to be responsive to pressure fluctuations of the pulsatile fluid flow in a distal direction (e.g., positive pressure) to actively dampen the pressure fluctuations and smoothen the pulsatile fluid flow.

Furthermore, the second biasing member <NUM> may be a gas at atmospheric pressure (<NUM> psi), such as atmospheric air, or a vacuum or a partial vacuum trapped within the second barrel <NUM> and/or the lumen defined by the second barrel <NUM>. In the example of <FIG>, the second biasing member <NUM> may be disposed within the second barrel <NUM> between the second movable seal member <NUM> and the cap <NUM> and/or the adjustable cap <NUM>. Accordingly, the dampening element <NUM> may be configured to actively dampen pressure fluctuations of the pulsatile fluid flow in the proximal direction (e.g., negative flow; during suction). The second biasing member <NUM> may bias and/or urge the second movable seal member <NUM> toward and/or into an initial position proximate the second end <NUM>. The second movable seal member <NUM>, in the initial position, may be at the second end <NUM> of the second barrel <NUM> immediately adjacent to and/or in contact with the cap <NUM> and/or the adjustable cap <NUM>. The second dampening element <NUM> may function similar to the dampening element <NUM> of <FIG> to be responsive to pressure fluctuations of the pulsatile fluid flow in a proximal direction (e.g., negative pressure) to actively dampen the pressure fluctuations and smoothen the pulsatile fluid flow.

In addition or alternatively, the dampening element <NUM> may be constructed with more than one barrel configured as the first barrel or as the second barrel. For example, the dampening element <NUM> may be configured with two or more "first" barrels each configured to actively dampen pressure fluctuations of the pulsatile fluid flow in the distal direction (e.g., positive flow; during infusion). Each of the "first" barrels may be configured with a different biasing force (e.g., gas pressure, etc.) to provide a desired responsiveness to the pulsatile fluid flow. Additionally or alternatively, the dampening element <NUM> may be configured with two or more "second" barrels each configured to actively dampen pressure fluctuations of the pulsatile fluid flow in the proximal direction (e.g., negative flow; during suction). Each of the "second" barrels may be configured with a different biasing force (e.g., gas or vacuum pressure, etc.) to provide a desired responsiveness to the pulsatile fluid flow. Varying combinations of multiple barrels are also contemplated.

As may be readily appreciated, while not explicitly illustrated, combinations of the configurations and/or features shown in <FIG> and <FIG> are also contemplated, including but not limited to multiple barrels configured as the first barrel and/or the second barrel, as well as configurations of the first barrel and/or the second barrel including different types of biasing members (e.g., elastic element, gas, vacuum, etc.).

<FIG> illustrates a partial cross-sectional view of another example of the dampening element <NUM>. The example illustrated in <FIG> combines selected features of the examples illustrated in <FIG> and <FIG>. However, it will be appreciated that the example of <FIG> may work equally well in and/or with features from any and/or all embodiments and/or examples of the dampening element <NUM> disclosed herein. For example, in some embodiments, the example of <FIG> may be constructed using selected features of the examples illustrated in <FIG> and <FIG>. Similarly, additional arrangements and/or combinations of features are also contemplated.

Compared to <FIG>, <FIG>, and <FIG> above, the example of <FIG> includes one or more barrels <NUM> formed as and/or within a single monolithic structure or housing. In some embodiments, the first barrel <NUM> and the second barrel <NUM> are formed as and/or within a single monolithic structure or housing. In some embodiments, the single monolithic structure may include two "first" barrels or two "second" barrels. Embodiments including additional barrels formed as and/or within the single monolithic structure are also contemplated.

Furthermore, in some embodiments, the dampening element <NUM> may include multiple instances of one or more barrels <NUM> being formed as and/or within a single monolithic structure. For example, the dampening element <NUM> may include two or more monolithic structures joined together using connectors <NUM>. In some embodiments, the dampening element <NUM> may include one monolithic structure including two or more "first" barrels, and one monolithic structure including two or more "second" barrels coupled together along the fluid pathway. Other arrangements and/or configurations are also contemplated.

The materials that can be used for the various components of the fluid management system, the dampening element, the connectors, the one or more barrels, the movable seal member, the biasing member, the cap and/or the adjustable cap, the fluid flow sensor, etc. (and/or other systems or components disclosed herein) and the various elements thereof disclosed herein may include those commonly associated with medical devices. In some embodiments, the fluid management system, the dampening element, the connectors, the one or more barrels, the movable seal member, the biasing member, the cap and/or the adjustable cap, the fluid flow sensor, etc., and/or components thereof may be made from a metal, metal alloy, polymer (some examples of which are disclosed below), a metal-polymer composite, ceramics, combinations thereof, and the like, or other suitable material. Some examples of suitable metals and metal alloys include stainless steel, mild steel, nickel-titanium alloy such as linear-elastic and/or super-elastic nitinol, or any other suitable materials. Some examples of suitable polymers may include polytetrafluoroethylene (PTFE), ethylene tetrafluoroethylene (ETFE), fluorinated ethylene propylene (FEP), polyoxymethylene (POM), polyether block ester, polyurethane, polypropylene (PP), polyvinylchloride (PVC), polyether-ester, polyamide, polyether block amide (PEBA), ethylene vinyl acetate copolymers (EVA), silicones, polyethylene (PE), and other suitable materials.

Claim 1:
A fluid management system (<NUM>), comprising:
a fluid pump (<NUM>) capable of generating a pulsatile flow of fluid;
a fluid pathway (<NUM>, <NUM>) for transporting the pulsatile flow of fluid from a fluid source through the fluid pump to a medical device;
a dampening element (<NUM>) in fluid communication with the fluid pathway, the dampening element comprising one or more barrels (<NUM>), each barrel including a movable seal member (<NUM>) disposed within the barrel and a biasing member (<NUM>) disposed within the barrel and engaged with the movable seal member, the dampening element being responsive to pressure fluctuations of the pulsatile fluid flow to actively dampen the pressure fluctuations and smoothen the pulsatile fluid flow;
a fluid flow sensor (<NUM>) disposed along the fluid pathway between the dampening element and the medical device to measure a flow rate of the smoothened pulsatile fluid flow; and
a controller (<NUM>) operatively connected to and/or in communication with the fluid flow sensor (<NUM>) and the fluid pump (<NUM>);
characterized in that
the fluid flow sensor (<NUM>) is a flow sensor for measuring a flow rate of the smoothened pulsatile fluid flow in both flow directions of the fluid pathway.