Patent Description:
The present invention is generally directed to systems and methods for intravenous ("IV") delivery, by which fluids can be administered directly to a patient. An intravenous delivery system according to the present disclosure is used broadly herein to describe components used to deliver the fluid to the patient, for use in arterial, intravenous, intravascular, peritoneal, and/or non-vascular administration of fluid. Of course, one of skill in the art may use an intravenous delivery system to administer fluids to other locations within a patient's body.

One common method of administering fluids into a patient's blood flow is through an intravenous delivery system. In many common implementations, an intravenous delivery system may include a liquid source such as a liquid bag, a drip chamber used to determine the flow rate of fluid from the liquid bag, tubing for providing a connection between the liquid bag and the patient, and an intravenous access unit, such as a catheter that may be positioned intravenously in a patient. An intravenous delivery system may also include a Y-connector that allows for the piggybacking of intravenous delivery systems and for the administration of medicine from a syringe into the tubing of the intravenous delivery system.

During infusion with gravity sets or pumps, an unattended complete infusion can lead to a loss of patency in the catheter due to blood diffusing back through the catheter tip. The blood will begin to coagulate, which may seal off the flow in the catheter, making it unusable.

<CIT> discloses an apparatus for administering parenteral liquids from a parenteral fluid container which provides a sufficient quantity of parenteral liquid to be administered at a slower than normal rate so as to afford a keep-vein-open (KVO) means. The apparatus utilizes a first orifice to afford a faster flow rate than a second orifice spaced away from the first orifice. The preferred means for regulating different flow rates of fluid through the two orifices are the dimensions of the orifices and filters having different mesh sizes. When the parenteral liquid is maintained in the reservoir in contact with the first orifice with the faster flow rate, liquid will pass through both orifices at a predetermined regular rate. When liquid no longer contacts the first orifice, as when the fluid container is depleted of liquid, the second orifice then comes into effect to afford a slower rate of liquid until a new container can be supplied.

Preferable embodiments are further laid out in the dependent claims. In accordance with various embodiments of the present disclosure, a drip chamber insert includes an elongate body portion having an upper surface, and a base portion positioned downstream of the elongate body portion for coupling to a drip chamber. The base portion has an upper surface and a lower surface defining an outlet orifice of the drip chamber insert. The drip chamber insert further includes a first chamber disposed in the elongate body portion and fluidly coupled to the upper surface via an inlet orifice and to the outlet orifice via the base portion, an anti-run-dry membrane disposed on the upper surface of the elongate body portion extending over the inlet orifice, and a second chamber disposed in the longitudinally extending body and extending from the upper surface to the base portion. A low flowrate orifice extends from a base of the second chamber into the base portion for fluidly coupling the second chamber with the outlet orifice.

In accordance with various embodiments of the present disclosure, a drip chamber assembly includes a drip chamber including a housing having an inlet for receiving an IV fluid, an outlet for dispensing the IV fluid to a patient, and a cavity defined by an inner surface of the housing. A drip chamber insert is disposed in the cavity. The drip chamber insert includes an elongate body portion having an upper surface, and a base portion positioned downstream of the elongate body portion, the base portion. The base portion defines an outlet orifice of the drip chamber insert and may be fluidly connected to the outlet of the drip chamber. The drip chamber further includes a first chamber disposed in the elongate body portion, a second chamber disposed in the elongate body portion and extending from the upper surface to the base portion, and a low flowrate orifice extending from a base of the second chamber into the base portion for fluidly coupling the second chamber with the drip chamber outlet. The first chamber includes an inlet orifice fluidly coupling the first chamber to the upper surface of the elongate body portion, and an anti-run-dry membrane disposed on the upper surface of the elongate body portion extending over the inlet orifice. The inlet orifice is fluidly coupled to the drip chamber inlet for receiving the IV fluid in a first flow condition. The second chamber has an open proximal end for receiving at least a portion of the IV fluid in a second flow condition.

The following figures are included to illustrate certain aspects of the embodiments and should not be viewed as exclusive embodiments. The subject matter disclosed is capable of considerable modifications, alterations, combinations, and equivalents in form and function, as will occur to those skilled in the art and having the benefit of this disclosure.

It is to be understood that the present disclosure includes examples of the subject technology falling within the scope of the appended claims. Various aspects of the subject technology will now be disclosed according to particular, but non-limiting, examples.

During infusion with gravity sets or a pump that does not have a keep-vein-open (KVO) function, an unattended complete infusion can lead to a loss of patency in the catheter due to blood diffusing back through the catheter tip. The blood will begin to coagulate, which will seal off the flow in the catheter, making it unusable. If infusion is to continue, the clinician must remove the catheter and re-insert a new one into the patient, which is costly, painful to the patient, and time consuming.

Some gravity sets attempt to address the above issue by employing a device that utilizes the patient's blood pressure to flow out through an injection site into a container with a plunger. The device is used mainly for keeping the vein open during the infusion of contrast media. The plunger is driven back with the blood pressure and can be driven with a motor to help draw out blood if the blood pressure is not enough to drive the plunger.

The present description relates in general to drip chambers, and in particular to a drip chamber including a drip chamber insert capable of slowing down the flow rate of the final volume of fluid in the drip chamber towards completion of infusion to allow the patient's vein to stay open until a clinician can tend to the completed infusion.

According to various embodiments of the present disclosure, the drip chamber assembly may be fluidly coupled to a catheter which may be inserted into a vein of a patient for infusion of an IV fluid and/or blood draw. In some embodiments, the drip chamber assembly includes a drip chamber having an additional component mounted or otherwise affixed therein. The additional component may be welded, glued, or otherwise similarly affixed to a base portion of the drip chamber. In some embodiments, the additional component may be a drip chamber insert that is affixed (for example, but not limited to welded or glued) into the drip chamber with the capability of slowing down the flow of the final volume (for example, but not limited to the final <NUM>-<NUM> milliliters (ml)) of IV fluid remaining in the drip chamber after depletion of the IV fluid in the IV fluid bag. The slowing of the flow rate of the IV fluid at completion of the infusion advantageously allows a patient's vein to stay open longer until a clinician can tend to the completed infusion.

In some embodiments, the drip chamber insert splits or otherwise partitions the drip chamber into two chambers: (i) a first chamber having an inlet orifice (also referred to herein as a normal flow orifice) for normal, unrestricted flow of the IV fluid, and (ii) a second chamber with a small orifice at a bottom or base of the second chamber that allows for a greatly reduced keep-vein-open (KVO) flow rate of the IV fluid. In some embodiments, an anti-run-dry filter or membrane may be attached to an upper surface of drip chamber insert extending over the top of the normal flow orifice to ensure that when the IV fluid in the drip chamber falls below the predetermined threshold value, the anti-run-dry membrane may restrict or otherwise block the remaining IV fluid from entering the normal fluid pathway in the first chamber. Accordingly, the remaining IV fluid in the drip chamber will flow through the path of less fluid flow resistance; the KVO fluid pathway delivers fluid to the patient at the greatly reduced flowrate via the low flowrate orifice.

For example, in some embodiments, the normal fluid pathway delivers the fluid at a flow rate ranging from about <NUM> milliliters/hour (ml/hr) to about <NUM>/hr, in some instances ranging from about <NUM>/hr to <NUM>/hr, more typically from about <NUM>/hr to <NUM>/hr, and in some embodiments approximately <NUM>/hr. In contrast, in some embodiments, the KVO fluid pathway delivers the fluid at a reduced flow rate ranging from about <NUM>/hr to about <NUM>/hr, in some instances ranging from about <NUM>/hr to <NUM>/hr, more typically from about <NUM>/hr to <NUM>/hr, and in some embodiments approximately <NUM>/hr. Accordingly, towards completion of infusion, the IV fluid is dispensed to the patient via the low flowrate orifice to allow the patient's vein to stay open until a clinician can tend to the completed infusion.

Though recited in terms of certain ranges, it will be understood that all ranges from the lowest of the lower limits to the highest of the upper limits are included, including all intermediate ranges or specific angles, within this full range or any specifically recited range.

According to various embodiments of the present disclosure, the IV set including the drip chamber and drip chamber insert mainly rely on gravity or suction from a pump for flow of the IV fluid. Once flow above the drip chamber stops (e.g., upon depletion of the IV fluid in the IV bag), the IV fluid in the drip chamber will continue to flow into the IV tubing to the patient. When the IV fluid level in the drip chamber drops to a predetermined threshold level, for example, a level corresponding to the height of the anti-run-dry membrane, the normal fluid path is blocked by the anti-run-dry membrane, thereby causing the remaining IV fluid to proceed through the KVO path and to the patient via the low flowrate orifice. The small orifice significantly lowers the flow rate of the remainder of the IV fluid.

Accordingly, the various embodiments of the present disclosure are advantageous in providing a drip chamber assembly capable of dispensing the last few milliliters of IV fluid to a patient at a reduced flow rate in order to keep the vein open once the IV fluid in the IV bag is depleted. The drip chamber assembly with drip chamber insert of the various embodiments described herein is further advantageous as it does not require modifications to the existing drip chamber other than affixing the drip chamber insert therein, thus only minimal change to the currently existing IV sets is necessary. As can be appreciated, no modifications to the pump are required. Further advantageously, the drip chamber insert does not require complex electronics or other technology in order to be integrated into the currently existing drip chamber. The drip chamber insert accomplishes the described function as a mechanical device with a mechanical connection. Additionally, the drip chamber assembly with the drip chamber insert of the various embodiments described herein is advantageous in that no additional training is required to use it. Further advantages are realized in time savings with respect to infusion therapy time for the medical personnel by eliminating the need to reinsert the catheter due to blood coagulation, which is commonly associated with gravity sets or pumps that do not have a keep-vein-open (KVO) function. Furthermore, since the catheter does not need to be reinserted, this has the effect of reducing or otherwise eliminating pain to the patient associated with reinserting the catheter.

<FIG> illustrates a multiple line IV extension set <NUM> that includes a drip chamber assembly <NUM> in accordance with some embodiments of the present disclosure. The drip chamber assembly <NUM> may be fluidly coupled to a catheter <NUM> which may be inserted into a vein of a patient for infusion of an IV fluid and/or blood draw. As depicted, IV set <NUM> includes a primary fluid system <NUM> and a secondary fluid system <NUM>. An IV pump (not shown) receives fluid from primary fluid system <NUM> and secondary fluid system <NUM> via a primary IV fluid line <NUM> and a secondary IV fluid line <NUM>, and may control and dispense the fluids therefrom to a patient <NUM>.

In some embodiments, primary fluid system <NUM> may include a primary fluid source or container such as a primary intravenous (IV) fluid bag <NUM>, which may include or contain a first medical fluid, for example, saline solution or other medicinal fluid or drug to be administered to the patient. As illustrated, IV tubing <NUM> may carry flow from the drip chamber assembly <NUM> to a Y-connector <NUM>. Check valve <NUM> may be disposed in tube <NUM> upstream from the Y-connector <NUM> and enables flow from fluid bag <NUM> to the IV pump (not illustrated) while preventing reverse flow (backflow) of fluid from auxiliary fluid system <NUM> toward fluid bag <NUM>.

In accordance with some embodiments, secondary fluid system <NUM> may include a secondary fluid source or container such as a secondary IV fluid bag <NUM>, which may contain a second medical fluid, for example, drugs or other secondary fluid to be supplied to the patient <NUM> for treatment via the catheter <NUM>. A secondary fluid line <NUM> carries flow from a drip chamber <NUM> to the Y-connector <NUM>.

In some embodiments, the second medical fluid may be different from the first medical fluid. However, the various embodiments of the present disclosure are not limited to the aforementioned configuration. In other embodiments, the first and second fluids may be the same.

According to various embodiments of the present disclosure, as illustrated in <FIG>, primary IV fluid bag <NUM>, which holds a primary fluid, may be positioned at a lower axial position or height than the secondary IV fluid bag <NUM>. For example, the primary IV fluid bag <NUM> may be hung on a suspension system or hanger and then the secondary IV fluid bag <NUM> may be hung above the primary IV fluid bag <NUM> and may be coupled to the secondary fluid line <NUM>, which may be connected to the primary fluid line <NUM> via a connector (e.g., a y-site connector).

<FIG> illustrates a perspective view of the drip chamber assembly <NUM>, in accordance with some embodiments of the present disclosure. According to various embodiments of the present disclosure, a drip chamber assembly <NUM> includes a drip chamber <NUM> and a drip chamber insert <NUM>. The drip chamber <NUM> may include a housing <NUM> having an inlet <NUM> for receiving an IV fluid, an outlet <NUM> for dispensing the IV fluid to a patient, and a cavity <NUM> defined by an inner surface <NUM> of the housing <NUM>. As depicted, the drip chamber insert <NUM> is disposed in the cavity <NUM> of the drip chamber housing <NUM>.

<FIG> illustrates a perspective view of the drip chamber <NUM> and drip chamber insert <NUM> of the drip chamber assembly <NUM> of <FIG>, in accordance with some embodiments of the present disclosure. In some embodiments, the drip chamber insert <NUM> includes a longitudinally extending or elongate body portion <NUM> having an upper surface <NUM> and a base portion <NUM> disposed downstream or at a distal end of the elongate body portion <NUM>. The base portion <NUM> define an outlet orifice <NUM> of the drip chamber insert <NUM> and be fluidly connected to the outlet <NUM> of the drip chamber <NUM>. In some embodiments, the drip chamber insert <NUM> includes a first chamber <NUM> and a second chamber <NUM> disposed in the elongate body portion <NUM>. The first chamber may include an inlet orifice <NUM> for receiving an IV fluid. An anti-run-dry membrane <NUM> may be disposed on the upper surface <NUM> of the elongate body portion <NUM> extending over the inlet orifice <NUM>. In some embodiments, the anti-run-dry membrane <NUM> is positioned at the inlet such that the IV fluid <NUM>, flowing from the IV fluid source (e.g., IV bag <NUM>), passes through the anti-run-dry membrane <NUM>. The anti-run-dry membrane <NUM> may have a plurality of pores, through which the IV fluid <NUM> flows, and may be formed of a hydrophilic material that resists passage of air through the pores while allowing liquid to pass through the pores.

In some embodiments, the inlet orifice <NUM> is fluidly coupled to the drip chamber inlet <NUM> for receiving the IV fluid <NUM> in a first flow condition (illustrated in <FIG>). The first flow condition as defined herein refers to a condition or state in which IV fluid flows in a regular or normal manner from the IV tubing into the drip chamber insert <NUM> and out through the drip chamber outlet <NUM> without otherwise being blocked, slowed down, reduced, or impeded by the drip chamber insert <NUM>.

As depicted, the second chamber <NUM> is disposed in the elongate body portion <NUM> and extend from the upper surface <NUM> to the base portion <NUM>. The second chamber <NUM> has an open proximal end <NUM> for receiving at least a portion of the IV fluid <NUM> in a second flow condition (illustrated in <FIG>). The second flow condition as defined herein refers to a keep-vein-open condition or state in which the flow rate of the final milliliters (ml) (for example, but not limited to the last <NUM>-<NUM>) of IV fluid in the drip chamber <NUM> exiting the drip chamber assembly <NUM> via the drip chamber assembly outlet orifice <NUM> is slowed down, reduced, or impeded so as to keep a vein of the patient open upon depletion of the IV fluid in the IV fluid bag <NUM>. To this effect, in some embodiments, the drip chamber insert <NUM> further includes a low flowrate orifice <NUM> extending from a distal end <NUM> of the second chamber <NUM> into the base portion <NUM> for fluidly coupling the second chamber <NUM> with the drip chamber outlet <NUM>. In some embodiments, the low flowrate orifice <NUM> may have a shape configured to slow down or otherwise reduce the rate at which the IV fluid passes from the drip chamber assembly into the drip chamber assembly outlet orifice <NUM>. For example, in some embodiments, the low flowrate orifice <NUM> may have a conical shape which tapers or otherwise reduces in diameter or cross-section distally into the base portion <NUM>, towards the outlet <NUM>.

For example, in some embodiments, the normal fluid pathway may deliver the fluid at a flow rate ranging from about <NUM> milliliters/hour (ml/hr) to about <NUM>/hr, in some instances ranging from about <NUM>/hr to <NUM>/hr, more typically from about <NUM>/hr to <NUM>/hr, and in some embodiments approximately <NUM>/hr. In contrast, in some embodiments, the KVO fluid pathway may deliver the fluid at the reduced or slowed-down flow rate ranging from about <NUM>/hr to about <NUM>/hr, in some instances ranging from about <NUM>/hr to <NUM>/hr, more typically from about <NUM>/hr to <NUM>/hr, and in some embodiments approximately <NUM>/hr. As a further example, in some embodiments, the KVO fluid pathway may deliver the fluid at a slower or reduced rate in the range of about <NUM>% to <NUM>% of the flow rate through the normal fluid pathway, in some instances in the range of about <NUM>% to <NUM>% of the flow rate through the normal fluid pathway, more typically from about <NUM>% to <NUM>% of the flow rate through the normal fluid pathway, and in some embodiments approximately <NUM>% of the flow rate through the normal fluid pathway. Though recited in terms of certain ranges, it will be understood that all ranges from the lowest of the lower limits to the highest of the upper limits are included, including all intermediate ranges or specific angles, within this full range or any specifically recited range.

According to various embodiments of the present disclosure, the elongate body portion <NUM> may further include a sidewall <NUM> longitudinally extending between the upper surface <NUM> and the base portion <NUM>. In particular, the sidewall <NUM> may extend from the upper surface <NUM> to a proximal end <NUM> of the base portion <NUM>. As depicted, the elongate body portion <NUM> may further include a fluid bypass orifice <NUM> disposed in the sidewall <NUM>. The fluid bypass orifice <NUM> may be fluidly coupled to the drip chamber outlet <NUM> via the low flowrate orifice <NUM> and the drip chamber insert outlet orifice <NUM>.

<FIG> illustrates a perspective view of the drip chamber <NUM> and drip chamber insert <NUM> of <FIG> in the first flow condition, in accordance with some embodiments of the present disclosure. As depicted, the inlet orifice <NUM>, the first chamber <NUM>, the drip chamber insert outlet orifice <NUM> and the drip chamber outlet <NUM> are fluidly coupled to define a first fluid pathway <NUM>. In operation, IV fluid <NUM> flows from the fluid source (e.g., the primary intravenous (IV) fluid bag <NUM>) into the drip chamber <NUM>. So long as the fluid in the drip chamber <NUM> remains above a predetermined fluid level, the first flow condition is activated and the IV fluid <NUM> exits the drip chamber assembly <NUM> via the first fluid pathway <NUM>. In some embodiments, the predetermined fluid level may be greater than or equal to <NUM>. However, the various embodiments of the present disclosure are not limited to this configuration. For example, in some embodiments, the predetermined fluid level may range from about <NUM>-<NUM>, in some instances range from about <NUM>-<NUM>, in other instances from about <NUM>-<NUM>, and in some embodiments approximately <NUM>. In some embodiments, a volume of the drip chamber insert <NUM> may range from about <NUM>-<NUM>. In yet other embodiments, where a burette may be used in place of the drip chamber insert, a volume capacity of the burette may be as high as up to <NUM>. Though recited in terms of certain ranges, it will be understood that all ranges from the lowest of the lower limits to the highest of the upper limits are included, including all intermediate ranges or specific angles, within this full range or any specifically recited range.

In accordance with various embodiments of the present disclosure, in the first flow condition where IV fluid in the drip chamber <NUM> is above a predetermined level, the IV fluid flowing from the IV bag <NUM> into the drip chamber assembly <NUM> passes through the anti-run-dry membrane <NUM> and enters the first chamber <NUM> via the inlet orifice <NUM>. In some embodiments, the predetermined level may be defined as the height at which the anti-run-dry membrane <NUM> is positioned. As depicted in <FIG>, in the first flow condition, the IV fluid flows in the first fluid pathway <NUM> in a uniform continuous unrestricted/unconstrained manner through the first chamber <NUM> and into the IV tubing <NUM> via the drip chamber insert outlet orifice <NUM> and out of the drip chamber outlet <NUM>. Accordingly, the IV fluid may be timely and continuously infused to a patient for example in the first flow condition (e.g., a standard infusion operation). In operation, as the infusion of the IV fluid continues, the IV fluid in the IV bag <NUM> may be depleted thereby causing a corresponding decrease of the level of IV fluid in the drip chamber <NUM> as the fluid continues to be dispensed into the IV tubing <NUM>. When the level of the IV fluid in the drip chamber <NUM> falls below the predetermined level, for example, but not limited to between <NUM> to <NUM>, the anti-run-dry membrane <NUM> as positioned over the inlet orifice <NUM> may enable a fluid column of significant length to be maintained within the first chamber <NUM> and the IV tubing <NUM> after cessation of flow of the IV fluid <NUM> from the IV bag <NUM> into drip chamber <NUM>, without permitting further IV fluid <NUM> to flow into the first chamber <NUM>.

In particular, in operation, once the IV fluid <NUM> stops flowing into the drip chamber <NUM>, for example, due to depletion of the IV fluid <NUM> in the IV fluid bag <NUM>, and the level of IV fluid in the drip chamber <NUM> falls below the predetermined level (e.g., the height at which the anti-run-dry membrane <NUM> is positioned), the anti-run-dry membrane <NUM> may act to restrict motion of IV fluid <NUM> into the inlet orifice <NUM>. For example, the anti-run-dry membrane <NUM> may have a plurality of pores, each of which has a size that causes the formation of a meniscus of the IV fluid <NUM> underneath the anti-run-dry membrane <NUM>. Each meniscus may, via capillary action, contribute to the support of a column of the IV fluid <NUM> in the first chamber <NUM> and IV tubing <NUM>. The anti-run-dry membrane <NUM> may thus be designed to facilitate support of the column of the IV fluid <NUM> within the first chamber <NUM>. In some embodiments, the anti-run-dry membrane may become saturated by means of the capillary action. In this condition, the pores of the anti-run-dry membrane <NUM> may become filled with fluid thereby providing increased resistance to flow of the IV fluid remaining in the drip chamber <NUM> into the first fluid pathway <NUM>. Accordingly, in this second flow condition the anti-run-dry membrane <NUM> may serve to block the first fluid pathway <NUM> to the IV fluid remaining in the drip chamber <NUM>.

<FIG> illustrates a perspective view of the drip chamber <NUM> and drip chamber insert <NUM> of <FIG> in the second flow condition, in accordance with some embodiments of the present disclosure. As depicted, the open proximal end <NUM> of the second chamber <NUM>, the low flowrate orifice <NUM>, the drip chamber insert outlet orifice <NUM>, and the drip chamber outlet <NUM> are fluidly coupled to define a second fluid pathway <NUM>. As further depicted, a third fluid pathway <NUM> may be defined longitudinally between the sidewall <NUM> of the elongate body portion <NUM> and the inner surface <NUM> of the drip chamber <NUM>, through the fluid bypass orifice <NUM>, and into the drip chamber insert outlet orifice <NUM> and the drip chamber outlet <NUM> via the low flowrate orifice <NUM>. In some embodiments, a fourth fluid pathway <NUM> may be defined longitudinally between the sidewall <NUM> of the elongate body portion <NUM> and the inner surface <NUM> of the drip chamber <NUM>, and circumferentially along an upper surface <NUM> of the base portion <NUM> between the sidewall <NUM> of the elongate body portion <NUM> and the inner surface <NUM> of the drip chamber <NUM>, through the fluid bypass orifice <NUM>, and into the outlet orifice <NUM> via the low flowrate orifice.

According to various embodiments of the present disclosure, the second, third, and fourth fluid pathways <NUM>, <NUM> and <NUM> may collectively define a keep-vein-open fluid path in the second flow condition. In particular, as described above, when the IV fluid in the drip chamber falls below the predetermined level (e.g., the height at which the anti-run-dry membrane <NUM> is positioned) the anti-run-dry membrane <NUM> may prevent the remaining IV fluid from flowing into the drip chamber assembly outlet orifice <NUM> via the inlet orifice such that the remaining IV fluid flows through the second, third, and fourth fluid pathways <NUM>, <NUM> and <NUM> defining the keep-vein-open fluid path having less resistance to flow than the obstructed first fluid pathway.

The aforementioned configuration of the drip chamber assembly having the drip chamber insert as described above is advantageous in that drip chamber insert <NUM> may be fixed (for example, welded or glued) into the drip chamber <NUM> functions to slow down the final milliliters (for example, but not limited to, the last <NUM>-<NUM>) of IV fluid in the drip chamber <NUM>. This slowing towards the end of the infusion allows the patient's vein to stay open longer until a clinician can tend to the finished infusion. The drip chamber insert <NUM> splits the drip chamber into two chambers; the first chamber for normal flow, and the second chamber with the low flowrate orifice at the bottom that allows for a greatly reduced flow rate as compared to the flowrate through the first chamber in the first flow condition (i.e., standard infusion flow). The anti-run-dry filter <NUM> attached to the top of the inlet orifice <NUM> (also referred to herein as the normal flow orifice) ensures that when the IV fluid in the drip chamber is low enough, the first fluid pathway <NUM> is stopped and the KVO fluid pathway <NUM>, <NUM>, and <NUM> has less resistance to fluid flow, thereby allowing the IV fluid to be administered to the patient via the outlet <NUM> at low flow rates sufficient to just keep the vein open.

Accordingly, the various embodiments of the present disclosure are advantageous in providing a drip chamber assembly capable of dispensing the last few milliliters of IV fluid to a patient at a reduced flow rate in order to keep the vein open once the IV fluid in the IV bag is depleted. The drip chamber assembly with drip chamber insert of the various embodiments described herein is further advantageous as it does not require modifications to the existing drip chamber other than affixing the drip chamber insert therein, thus only minimal change to the currently existing IV sets is made. As can be appreciated, no modifications to the pump are required. Further advantageously, the drip chamber insert does not require complex electronics or other technology in order to be integrated into the currently existing drip chamber. The drip chamber insert is a mechanical device with mechanical connection. Additionally, the drip chamber assembly with drip chamber insert of the various embodiments described herein is advantageous in that no additional training required to use it. Further advantages are realized in time savings with respect to infusion therapy time for the medical personnel by eliminating the need to reinsert the catheter due to blood coagulation, which is commonly associated with gravity sets or pumps that do not have a keep-vein-open (KVO) function. Furthermore, since the catheter does not need to be reinserted, the drip chamber insert can reduce or otherwise eliminate pain to the patient associated with reinserting the catheter.

It is understood that the specific order or hierarchy of steps, or operations in the processes or methods disclosed are illustrations of exemplary approaches. Based upon implementation preferences or scenarios, it is understood that the specific order or hierarchy of steps, operations or processes may be rearranged. Some of the steps, operations or processes may be performed simultaneously. In some implementation preferences or scenarios, certain operations may or may not be performed. Some or all of the steps, operations, or processes may be performed automatically, without the intervention of a user. The accompanying method claims present elements of the various steps, operations or processes in a sample order, and are not meant to be limited to the specific order or hierarchy presented.

Furthermore, to the extent that the term "include," "have," or the like is used, such term is intended to be inclusive in a manner similar to the term "comprise" as "comprise" is interpreted when employed as a transitional word in a claim.

Claim 1:
A drip chamber insert (<NUM>), comprising:
an elongate body portion (<NUM>) comprising an upper surface (<NUM>), and a base portion (<NUM>) positioned downstream of the elongate body portion for coupling to a drip chamber, the base portion (<NUM>) having an upper surface (<NUM>), and a lower surface (<NUM>) defining an outlet orifice (<NUM>) of the drip chamber insert;
a first chamber (<NUM>) disposed in the elongate body portion (<NUM>) and fluidly coupled to the upper surface (<NUM>) of the elongate body portion via an inlet orifice (<NUM>) and to the outlet orifice (<NUM>) via the base portion (<NUM>);
an anti-run-dry membrane (<NUM>) disposed on the upper surface (<NUM>) of the elongate body portion extending over the inlet orifice (<NUM>), and configured to allow a liquid to pass therethrough;
a second chamber (<NUM>) disposed in the elongate body portion (<NUM>) and extending through the upper surface (<NUM>) of the elongate body portion to the base portion (<NUM>), the second chamber (<NUM>) having an open proximal end (<NUM>) configured to receive at least a portion of the liquid into the second chamber (<NUM>); and
a low flowrate orifice (<NUM>) extending from a base of the second chamber into the base portion (<NUM>) for fluidly coupling the second chamber (<NUM>) with the outlet orifice (<NUM>).