Intravenous tubing venting assembly

Provided herein is a method and apparatus for venting of intravenous tubing to remove air bubbles, and more particularly, to a venting valve that allows air bubbles to escape along a venting path while not permitting fluid passage through the venting path. An example air extraction device may include: a chamber; a fluid inlet to convey fluid from intravenous tubing into the chamber; a fluid outlet to convey fluid from the chamber to intravenous tubing for supplying to a patient; a top portion of the chamber; a branch tube extending from the top portion of the chamber, where the branch tube receives air from the fluid in the chamber; and a ball received within the chamber, where the ball is configured to rise with an influx of fluid to the chamber from the fluid inlet and to seal off the branch tube from the chamber in response to the fluid level rising to the top portion of the chamber.

TECHNOLOGICAL FIELD

The present disclosure relates to venting of intravenous tubing to remove air bubbles, and more particularly, to a venting valve that allows air bubbles to escape along a venting path while not permitting fluid passage through the venting path.

BACKGROUND

In a healthcare context, fluids are conventionally introduced to a body by way of intravenous (IV) introduction from a fluid source, such as an IV bag or syringe, through IV tubing and into a patient through an IV catheter. While the goal is to convey fluids intravenously, air bubbles within the fluid can be problematic. Air bubbles in an intravenous delivery system may be conveyed to a patient and introduced into the patient's veins. An air bubble within the veins of a patient is known as an air embolism. Air embolisms can be deadly, particularly in the most vulnerable patients, such as premature infants. Current methods to avoid introducing air embolisms into a patient include sensors, such as within an IV pump, to detect air bubbles and to cease IV delivery when an air bubble is detected. To remove air bubbles, healthcare providers will often tap or flick intravenous tubing and hardware to move bubbles back up the IV tubing away from the patient. However, this method is rudimentary and often not entirely successful.

SUMMARY

An objective of this present disclosure is to provide a mechanism to remove air bubbles from intravenous tubing using an air extraction device. Embodiments provided herein include an air extraction device including: a chamber; a fluid inlet to convey fluid from intravenous tubing into the chamber; a fluid outlet to convey fluid from the chamber to intravenous tubing for supplying to a patient; a top portion of the chamber; a branch tube extending from the top portion of the chamber, where the branch tube receives air from the fluid in the chamber; and a ball received within the chamber, where the ball is configured to rise with an influx of fluid to the chamber from the fluid inlet and to seal off the branch tube from the chamber in response to the fluid level rising to the top portion of the chamber.

According to an example embodiment, the chamber is formed of a flexible material, where fluid is pumped through the chamber in response to a squeezing and releasing of the chamber. The chamber may be configured to release airlocks in the intravenous tubing leading to the fluid inlet in response to squeezing and releasing of the chamber. The fluid inlet may include a fluid inlet tube extending into the chamber, where the fluid outlet includes a fluid outlet tube extending into the chamber, and where the fluid inlet tube extends closer to the top portion of the chamber than the fluid outlet tube. The fluid inlet tube and the fluid outlet tube each extend into the chamber from a bottom of the chamber.

According to an example embodiment of the present disclosure, the ball is buoyant relative to the fluid. In response to the ball rising in the chamber and sealing off the branch tube from the chamber, fluid is precluded from flowing from the chamber into the branch tube. In response to air bubbles received into the chamber from the fluid inlet lowering the fluid level in the chamber, air is allowed to escape from the chamber into the branch tube. The branch tube may include a first end and a second end, where the first end of the branch tube is connected to the top portion of the chamber, and the second end of the branch tube is connected to an air reservoir.

Embodiments described herein may include a clamp configured to support the air extraction device, where the clamp secures the branch tube in a clip of the clamp. The clip of the clamp pinches and prevents the flow of air through the branch tube in response to the clamp not being secured to an object. The clip of the clamp opens and permits flow of air through the branch tube in response to the clamp being secured to an object.

Embodiments provided herein include an air extraction device for removing air from intravenous tubing, the device including: a chamber; a fluid inlet tube extending into the chamber to convey fluid from the intravenous tubing into the chamber; a fluid outlet tube extending into the chamber to convey fluid from the chamber to intravenous tubing for supplying to a patient, where the fluid inlet tube extends further into the cavity than the fluid outlet tube; a to portion of the chamber; a branch tube extending from the top portion of the chamber, where the branch tube receives air from the fluid in the chamber; and a ball received within the chamber, where the ball is configured to rise with an influx of fluid to the chamber from the fluid inlet and to seal off the branch tube from the chamber in response to a level of the fluid rising to the top portion of the chamber. The fluid conveyed from the intravenous tubing into the chamber includes air bubbles, and the fluid conveyed from the fluid chamber to the intravenous tubing for supplying to a patient does not include air bubbles. The air bubbles from the fluid conveyed from the intravenous tubing into the chamber exits the chamber through the branch tube.

DETAILED DESCRIPTION

As noted above, fluid delivery to a patient intravenously through IV tubing can be challenging. Fluid delivery while removing air bubbles from the IV tubing is inefficient and sometimes ineffective. Embodiments described herein provide a device to remove air from IV tubing without interrupting fluid flow from a fluid source, such as an IV bag or syringe, to a patient. Embodiments may be employed in any setting where intravenous fluid introduction to a patient is performed using IV tubing.

According to an example embodiment provided herein, an air extraction device in-line with intravenous tubing to remove air from fluid flowing through the tubing and to carry the air to a reservoir or vent where the air is safely removed while enabling fluid flow through the IV tubing without air bubbles present after the in-line extraction device. The air extraction device described herein extracts air from IV tubing proximate a patient by establishing a branch from the IV tubing that provides a pathway for air removal from the fluid flow through the tubing. In order to prevent rapidly-infused medications from being forced into the branch tube, a ball valve is used. The fluid as described herein may be any fluid that is supplied to a patient via intravenous infusion. Fluid such as saline and/or liquid medications, for example. Fluid may also include blood infused intravenously from a reservoir or blood infused from a closed-loop dialysis system, for example.

Orientation of the air extraction device is imperative to function due to the air having a lower specific gravity than the fluid, where air rises relative to the fluid regardless of the gaseous make up of the air or the type of fluid being used in the IV. The term “air” is used herein to describe any gaseous substance found within the IV system. While atmospheric air is primarily Nitrogen and Oxygen, the air found in an intravenous system may be atmospheric air or may be air from within an IV bag, which may be anaerobic or have other chemical composition. Thus, the term “air” as used herein may be gases of any chemical composition.

Due to the air within IV tubing being lighter than the fluid flowing through the IV tubing, the orientation of the air extraction device is important for proper extraction of the air. The branch tube from which air is extracted from the IV tubing is raised relative to the IV tubing to promote air extraction. Embodiments provided herein further include a mechanism by which proper orientation of the air extraction device is maintained while also providing a mechanism to close the branch tube when the orientation of the air extraction device is improper.

FIG.1illustrates a conventional IV arrangement for which a patient100receives a fluid intravenously from an IV bag110suspended on a stand120. As shown, the fluid from the IV bag110flows through a first tubing section112to an IV pump130and out of the IV pump along second tubing section114and into an arm of the patient100at IV site116. The IV pump130is optional and not present in all situations in which a patient receives fluid intravenously. Optionally, the fluid may be fed through the IV tubing by gravity with the IV bag110suspended at sufficient height that the fluid flows through the tubing at a metered pace to the patient100. The patient100of the illustrated embodiment is in a hospital bed140with bed rails142. The hospital bed140is one conventional situation for a patient receiving intravenous fluids; however, it is not intended to be limiting.

FIG.2illustrates an IV arrangement including an air extraction device150according to example embodiments of the present disclosure. The air extraction device150is positioned along the second tubing section114of the illustrated scenario, located close to the patient100. The air extraction device150includes a branch tube152extending from the air extraction device150, where the branch tube terminates at a reservoir160that may be present to collect the air extracted from the IV fluid. The reservoir160is optional and may be present to capture and monitor a volume of air extracted by the air extraction device150. Further, the reservoir may function to maintain the IV fluid system, from the IV bag110to the patient100, a closed system such that contaminants cannot be introduced to the system.

According to the illustrated embodiment ofFIG.2, fluid flows from the IV bag110through the first tubing section112to the IV pump130, and along the second tubing section114. While air has several ways of being introduced to the tubing, air may be introduced when medications are delivered to the IV tubing via a syringe connector. A syringe injecting medicine into the IV tubing may result in some amount of air introduced to the IV tubing. This may be due to air in the syringe, which may occur due to the method of filling the syringe, or the air bubbles may form through cavitation, for instance. Regardless, air bubbles traveling along the second tubing section114encounter the air extraction device150. The air extraction device150separates the air bubbles from the fluid and expels the air along the branch tube152to the reservoir160while the IV fluid continues along the patient-side IV tubing118to the patient IV site116.

FIG.3illustrates a diagram of features of the air extraction device150ofFIG.2shown in greater detail. As shown, the air extraction device150includes a fluid inlet214where the second tubing section114enters chamber200. The fluid202in the chamber flows out through fluid outlet218to patient-side IV tubing118. The fluid202fills the chamber200to a fluid level204. A ball206floats at the fluid level204. The ball206density may be chosen based on the type of fluid that is to be intravenously provided to a patient; however, the density is generally such that the ball remains buoyant on the fluid while only partially submerged below the fluid level204. A less dense ball206may be more responsive to fluctuations in fluid; however, a less dense ball may also be subject to premature closing of the ball valve while a more dense ball, while still remaining buoyant in the fluid, may respond more slowly. A more dense ball206may permit fluid flow into the branch tube152in response to a sudden influx of fluid into the chamber200.

The chamber200includes at a top portion208that narrows to meet the branch tube152. The narrowing top portion208may be frustoconical or frusto-pyramidal whereby as the fluid level204of the fluid202rises, the ball206floats up. As the fluid level204continues to rise, the ball206is guided by the narrowing top portion208to close off or seal the branch tube152. This ball valve functionality prevents or reduces the likelihood of fluid flow into the branch tube152, and allows the fluid202to continue to flow from the chamber200through fluid outlet218along the patient-side IV tubing118. As will be described further below, this ball valve functionality does not enable air flow through the air extraction device150to the patient despite being able to close off the branch tube152in response to a high fluid level204.

FIG.4illustrates the air extraction device during operation, while fluid202is flowing in through the fluid inlet214and out through fluid outlet218of the chamber200. As shown, when fluid is received at the chamber200with air bubbles230, the air bubbles230float up within the chamber200due to the top portion208being elevated relative to the inlet214and the air being lighter than the fluid202. The air bubbles230crest the fluid level204and the air is carried up the branch tube152as illustrated by arrows232. Maintaining fluid level204results in any air introduced into the chamber200further pushing air in the chamber up through the branch tube152. Fluid202, with air bubbles230having escaped, then flows through fluid outlet218to the patient-side IV tubing118as shown by arrows234for delivery to the patient100.

The illustration ofFIG.4demonstrates the primary functional purpose of the air extraction device150whereby air is separated from the fluid202and allowed to escape from the IV tubing by way of the branch tube152without disrupting the fluid flow from the IV bag110to the patient100. This extraction of the air from the fluid reduces the chances of an air embolism thereby improving the safety of intravenous fluid infusion. The fluid inlet214is elevated within the chamber200relative to the fluid outlet218to further discourage air from exiting through the fluid outlet218as the air accumulates in the top portion208of the chamber as described above.

In some situations, fluid may flow rapidly through the IV fluid system illustrated inFIG.2. Such situations include where rapid rehydration or medication absorption is needed by a patient. In these situations, it remains imperative to extract air from the fluid flow while also precluding fluid from escaping from the system through the branch tube152.FIG.4illustrates an example embodiment in which fluid is flowing rapidly through fluid inlet214into the chamber200. When this begins to happen, the fluid level204will rise quickly. When the fluid level204rises, the ball206is carried by the fluid into the top portion208of the air extraction device150where the ball206plugs the exit of the chamber to the branch tube152. The fluid202is thus precluded from flowing through the branch tube152and away from the patient. The fluid is instead forced to exit the chamber200through the fluid outlet218along the patient-side IV tubing118to the patient100for delivery of the rapidly flowing fluid.

While the branch tube152is plugged during rapid fluid flow, the air extraction device150continues to function.FIG.6illustrates that if air bubbles are received while fluid is flowing rapidly through the air extraction device150, the bubbles will rise in the chamber200and accumulate in the top portion108of the chamber around the ball206. When a sufficient amount of air bubbles have been received, the fluid level204descends and opens a pathway for the air to escape through the branch tube152. During rapid fluid flow, the fluid level204may rise to close the branch tube152with ball206, and periodically sufficient air bubbles may be received in the chamber to lower the fluid level204sufficiently to enable air to escape through the branch tube152whereupon the fluid level204may rise again to close the branch tube152with the ball206. Thus, even during rapid fluid flow, the air extraction device150continues to function to extract air from the fluid and expel the air along the branch tube152.

FIG.7illustrates a perspective view of the air extraction device with dimensions of an example embodiment. As shown, an air extraction device150of an example embodiment may have a width of 20 millimeters and a height of 60 millimeters. The shape of the chamber200may be cylindrical with a frustoconical top portion208. Optionally, the chamber200may be of a flexible membrane with no structural shape, whereby the chamber200is relatively flat when empty, but inflates with fluid as intravenous fluid enters the chamber through fluid inlet214. Even if the chamber200includes a structural shape, the chamber may be constructed of a flexible material, such as the same material as the intravenous tubing or of a silicone, for example. Embodiments in which the chamber is flexible provide an advantage that the chamber200can be used as a pump to remove airlocks from the intravenous tubing.

The flexible nature of the chamber200of some embodiments is counterintuitive to a chamber that includes a ball check valve as disclosed herein. This is due to a conventional ball check valve having a rigid enclosure to enable the ball to move consistently and repeatably. However, applicant has developed a chamber200that can be flexible while including a ball206of a check valve to prevent fluid flow through the branch tube152. According to example embodiments described herein, the ball206only needs to close the branch tube152in response to the chamber filling with fluid. When the chamber200fills with fluid, the chamber volume becomes substantially the maximum volume possible for the chamber, thus establishing the shape defined by the flexible material in an expanded position. As the ball206is only employed for function when the chamber200is filled, the chamber is substantially the same repeatable, and defined shape whenever the ball206is used. Thus, while the chamber may be of a flexible and pliable material that can be used for pumping of fluid as detailed herein, the ball206valve sealing retains full functionality despite the flexible nature of the chamber.

Airlocks occur in intravenous tubing where air bubbles exist in the tubing and preclude fluid flow or the flow of the air bubbles through the tubing. Historically these airlocks have been removed by tapping or flicking the IV tubing to drive the air up the tubing to an IV bag. However, embodiments described herein can pump fluid through the chamber200while simultaneously expelling air through the branch tube152by squeezing the chamber. This pumping action may draw the airlock into the chamber200through the fluid inlet214where the air passes through the branch tube while the fluid continues to flow through the fluid outlet218. This pumping action does not preclude functionality of the air extraction device150and instead benefits the air extraction device by providing additional functionality of being a fluid/air pump that pulls fluid and air through the inlet214and expels the fluid and air through different outlets while preventing air from flowing to a patient.

In order for the air extraction device150to properly function, the chamber200should be maintained at the height of the patient or lower such that air does not enter the patient-side IV tubing118from the chamber. The arrangement of the air extraction device150below the IV bag110enables flow of fluid to the air extraction device150by gravity feeding or by IV pump130. Further, maintaining the reservoir at the height of the patient's IV site116or lower does not allow air to enter the patient-side IV tubing118. To help maintain this arrangement, embodiments described herein may employ a clip from which the air extraction device150is hung. The clamp may include a normally-closed clip that closes down on the branch tube152to preclude flow of any fluid or air through the branch tube152while the clamp is not attached to an object.

FIG.8illustrates an example clamp300that may be used to close the branch tube152while the clamp is not attached to an object, and to open the branch tube152when attached to an object, such as a bed rail320of a hospital bed. The clamp300of the illustrated embodiment includes two primary components of a first part302and a second part304. In the closed position, whereby the branch tube152is closed, a spring biases the second part304toward the first part302, closing a clip308formed by the two parts. This pinches the branch tube152as shown in the top view closed illustration. When the clamp is attached to an object such as a bed rail320of a hospital bed, the first part302is pushed away from the second part304compressing the spring310against element306while opening the clip308. Thus, when the clamp is attached to an object, as to be done by a nurse or attending caregiver, the air extraction device150is ensured to be in the correct orientation with the branch tube152extending upward from the chamber200. If the clamp were not clamped to an object, as shown in the “closed” position ofFIG.8, the orientation of the air extraction device150is not ensured, such that the branch tube152is closed.

Embodiments of the air extraction device described herein may be positioned anywhere between the IV fluid source (e.g., the IV bag110) and the patient100provided the air extraction device150is positioned at an appropriate elevation with respect to the fluid source and the patient. However, according to embodiments in which the air extraction device150is located downstream of an IV pump130as shown inFIG.2, the air extraction device may substantially eliminate any air bubbles from the IV tubing. IV pumps130may include air bubble detection means to detect when air exists in the IV tubing. When air is detected in the IV tubing, the IV pump130may cease operation until the issue is rectified by a medical professional, and/or the air detection means may cause an alarm to sound to alert an attending medical professional of the detected air in the IV tubing. When employing the air extraction device150as described herein, the air bubble detection means of an IV pump may be turned off since air bubbles passing through the IV pump will be mitigated downstream by the air extraction device. The turning off of the air bubble detection means and associated alarm reduces the time an attending medical professional has to spend dealing with alarms, both false alarms and legitimate alarms, such that the efficiency and efficacy of the medical professionals can be improved.