Apparatus for gravitational IV flow sensing via mass change sensor and droplet counting device

Abstract

An apparatus for gravity IV flow sensing via a mass change sensor and a droplet counting device is disclosed, in particular, an infusion control system capable of controlling and monitoring medical fluid administration of gravity-based medical fluid infusion, where the gravity infusion control system may be coupled with an intravenous administration kit to control the infusion of gravity-based medical fluid. And may include a mass change sensor and a droplet counter.

Description

Background Art

[0001] The present disclosure relates generally to the administration of medical fluids, such as intravenous (IV) medical fluid therapy, and more particularly to devices, systems and methods for controlling and monitoring gravity-based medical fluid administration. Flow sensing capabilities, such as mass change sensors used in conjunction with drop counting devices, allow for higher precision flow rates and wider ranges of control (e.g., about 2 mL / hr to over 15,000 mL / hr).

[0002] IV fluid delivery systems are used to deliver or infuse medical fluids to a patient at a controlled rate. Several such IV fluid delivery systems exist, including gravity-based systems that utilize gravity pressure to direct the medical fluid from an IV bag through tubing to the patient, and pump-based systems that use a mechanical pump that can engage tubing to direct the medical fluid from the IV bag to the patient.

[0003] A gravity-based infusion system can include an IV dosing set that includes an IV bag, a drip chamber, an infusion line, and a flow control device. The flow of the medical fluid to the patient is controlled by a flow control device, such as a roller clamp, a pinch clamp, or a flow valve. Typically, the patient will receive the full volume of the medical fluid from the IV bag unless the flow is interrupted, such as when the patient or a caregiver blocks the infusion line or disconnects the infusion line from the patient. A pump-based infusion system includes similar components to a gravity-based infusion system; however, an infusion pump can be used instead of the flow control device used in a gravity-based infusion system to control the flow and volume of the drug directed to the patient. Summary of the invention

[0004] Although pump-based infusion systems can provide the ability to control and monitor the administration of medical fluids, such as by controlling the fluid flow rate and volume of the medical fluid directed to the patient, pump-based infusion systems may be more complex and more expensive relative to gravity-based infusion systems. In addition, both gravity-based and pump-based infusion systems require a caregiver or user to assemble and configure the system, including ensuring that each component is prepared and properly connected together, and ensuring that the infusion and fluid flow parameters are set as expected. Some systems, such as gravity-based infusion systems, may require a caregiver or user to prime the fluid pathway and maintain and / or adjust the fluid flow parameters throughout the infusion. In addition, some infusion systems may not provide notification if a complication or error is encountered, such as air in the fluid pathway or the system is accidentally disconnected from the patient.

[0005] According to at least some embodiments disclosed herein, it is recognized that although gravity-based infusion systems may provide a lower cost alternative to pump-based infusion systems, pump-based and gravity-based infusion systems require caregivers to set up, maintain, and monitor several aspects of medical fluid administration. Therefore, the use of gravity-based infusion systems may expose patients to several potential complications and errors, which may result in patient injury or inadequate care.

[0006] Thus, the present disclosure addresses the operational challenges encountered in existing systems and methods for administering medical fluids using gravity-based infusion systems, and provides a device for controlling and monitoring the administration of medical fluids that can protect patients from complications during infusion therapy, improve clinician and caregiver workflow, maintain patient mobility, reduce medication administration errors, improve medication safety, improve drug delivery accuracy and rate stability, reduce costs, and improve documentation efficiency, as well as prevent, detect, and resolve complications such as occlusions, extravasation, and air in the fluid pathway.

[0007] Features of the present embodiment may provide a gravity infusion control system that may allow control of any of the aspects including, but not limited to, fluid flow, dose volume, priming of an IV dosing set, and automatic stopping and / or starting of an infusion. Additionally, aspects of the present disclosure may provide monitoring of aspects of the fluid pathway of an IV dosing set, including, but not limited to, pressure, fluid flow, occlusions, presence of air, fluid flow, leaks, infiltration, and potential occurrence of tampering with the IV dosing set.

[0008] Embodiments of the present disclosure provide a gravity infusion control system, which includes: a drip chamber containing an infusate configured to be fluidically coupled to a patient through an IV tube extending therebetween; a mass change sensor configured to detect any one of a weight change or movement of the infusate in the drip chamber; and a drop detector configured to detect drops of the infusate falling from the drip chamber. In some embodiments, the gravity infusion control system also includes a user interface that controls the flow rate of the gravity infusion system. In some embodiments, the mass change sensor is a weighing sensor or a weight. In some embodiments, the drip chamber is coupled to the mass change sensor by an arm, a hook, or a clamp. In some embodiments, the infusate fluid flow is directed through the IV tube by gravity pressure. In some embodiments, the drop detector is an infrared light emitter and receiver.

[0009] In some embodiments, the infusion fluid flow is configured to provide a flow rate of about 50 mL / hour, about 100 mL / hour, about 150 mL / hour, about 200 mL / hour, about 250 mL / hour, about 300 mL / hour, about 350 mL / hour, about 400 mL / hour, about 450 mL / hour, or about 500 mL / hour. In some embodiments, the infusion fluid flow is configured to provide a flow rate of about 2 mL / hr, about 5 mL / hr, about 10 mL / hr, about 15 mL / hr, about 20 mL / hr, about 25 mL / hr, about 30 mL / hr, about 35 mL / hr, about 40 mL / hr, about 55 mL / hr, or about 5 mL / hr. In some embodiments, the infusion fluid flow is greater than 500 mL / hr. In some embodiments, the gravity infusion control system also includes one or more of an air detector in the pipeline, a leak detector, an external pressure module, an anti-tampering module, an information and control module, and a connection module.

[0010] Embodiments of the present disclosure provide a gravity infusion control system, which includes an intravenous administration kit coupled to a medical fluid reservoir and a flow sensor coupled to the intravenous administration kit, the gravity infusion control system being configured so that the flow sensor can detect any change in the mass or movement of the medical fluid reservoir. In some embodiments, the flow sensor includes a mass change sensor and a drop detector. In some embodiments, the flow sensor is configured to detect any one of a weight change or movement of the medical fluid reservoir of the intravenous administration kit. In some embodiments, the mass change sensor is a weighing sensor or a weight. In some embodiments, the drop detector is an infrared light transmitter and receiver.

[0011] Embodiments of the present disclosure provide a method for providing a gravity infusion control system, comprising coupling a medical fluid reservoir of an intravenous administration kit to a flow detection interface, wherein the flow detection interface includes a flow sensor configured to detect any of a mass change or movement of the medical fluid reservoir, and selecting a flow rate through the intravenous administration kit using a processor, wherein the processor is coupled to the flow detection interface and the flow control interface so that the processor receives data from the flow sensor to determine the presence of fluid flow through the tube of the intravenous administration kit. In some embodiments, the selected flow rate is about 50 mL / hour, about 100 mL / hour, about 150 mL / hour, about 200 mL / hour, about 250 mL / hour, about 300 mL / hour, about 350 mL / hour, about 400 mL / hour, about 450 mL / hour, or 500 mL / hour. In some embodiments, the selected flow rate is about 2 mL / hr, about 5 mL / hr, about 10 mL / hr, about 15 mL / hr, about 20 mL / hr, about 25 mL / hr, about 30 mL / hr, about 35 mL / hr, about 40 mL / hr, about 55 mL / hr, or about 5 mL / hr. In some embodiments, the selected flow rate is greater than 500 mL / hr; in some embodiments, the flow sensor includes a mass change sensor and a droplet detector.

[0012] Additional features and advantages of the subject technology will be set forth in the following description, and in part will be apparent from the description, or may be learned by practicing the subject technology. The advantages of the subject technology will be realized and obtained through the structures particularly pointed out in its written description and embodiments and the accompanying drawings.

[0013] It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the subject technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Various features of exemplary embodiments of the present invention are described below with reference to the accompanying drawings. The illustrated embodiments are intended to illustrate but not limit the present invention. The accompanying drawings include the following figures:

[0015] Figure 1 A gravity infusion control system for use with an IV drug administration set coupled to a patient is shown in accordance with aspects of the present disclosure.

[0016] Figure 2 A gravity infusion control system for use with an IV administration set including a mass change sensor is shown in accordance with aspects of the present disclosure.

[0017] Figure 3 A gravity infusion control system for use with an IV administration kit including a mass change sensor and a drop counter is shown in accordance with aspects of the present disclosure.

[0018] Figure 4 is a graph showing a calibration curve providing the average drop weight at a specific drop rate.

[0019] Figures 5A-5C Different infusate droplet sizes resulting from different drip rates are shown.

[0020] Figure 6 is a calibration curve showing normal infusion rate.

[0021] Figure 7 is a graph showing the signal-to-noise ratio of a mass change sensor during a keep vein open (KVO) infusion.

[0022] Figure 8 is a graph showing a calibration curve for rapid infusion rate.

[0023] Fig. 9 Potential access points for infusate theft are shown. DETAILED DESCRIPTION

[0024] In the following detailed description, many specific details are set forth to provide a comprehensive understanding of the subject technology. It should be understood that the subject technology can be practiced without some of these specific details. In other cases, well-known structures and technologies are not shown in detail to avoid obscuring the subject technology.

[0025] In addition, although the present description sets forth specific details of various embodiments, it should be understood that the present description is illustrative only and should not be construed as limiting in any way. In addition, it is contemplated that although specific embodiments of the present disclosure may be disclosed or illustrated in the context of an IV administration kit, these embodiments may also be used in other fluid delivery systems. In addition, various applications of such embodiments and modifications thereof that may occur to a person skilled in the art are also included in the general concepts described herein.

[0026] According to some embodiments, the present disclosure discusses various features and advantages of a gravity infusion control system. A gravity infusion control system can be provided for providing numerous improvements in controlling and monitoring the administration of medical fluids. A gravity infusion control system can monitor and control various aspects of the administration of medical fluids using an IV administration kit, and can prevent, detect, and resolve potential or actual complications associated with the administration of medical fluids.

[0027] The gravity infusion control system includes a user interface, a flow detection interface, and a flow sensing interface. The user interface allows a user to set and / or adjust the operating characteristics of the gravity infusion control system, including but not limited to the dose and / or volume of the medical fluid to be directed to the patient, the flow rate of the drug, the start and / or stop parameters of the medical fluid administration, and the priming of the fluid pathway of the medical fluid. In some embodiments of the present disclosure, the user interface may include a graphical user interface.

[0028] The flow sensing device described herein is implemented with two input signals. These signals are the mass change of the infusate storage container, and the detection of a drop of fluid falling from a controlled diameter (e.g., a drip chamber). Flow sensing is critical to the performance of a gravity infusion control system to ensure that the proper rate is achieved and that all derived parameters for the user are correct (e.g., estimated time until infusion is complete).

[0029] The flow sensing interface allows a gravity infusion control system to couple to a medical fluid reservoir or container and detect the occurrence of flow from or through the medical fluid reservoir.

[0030] The flow detection interface includes an IV administration kit coupler configured to engage or retain a portion of an IV administration kit that forms a medical fluid reservoir, such as an IV bag or a drip chamber. The flow detection interface also includes a flow sensor configured to detect any of a mass change or movement of the medical fluid reservoir to determine the occurrence of flow from or through the medical fluid reservoir. In some embodiments of the present disclosure, the flow sensor may include any of a drop sensor, a weight change sensor, and / or an optical sensor.

[0031] In some embodiments of the present disclosure, the flow detection interface is configured with one or more IV administration kit couplers having a structure for coupling with an IV bag and / or a drip chamber. The structure of the IV bag can be formed as an arm, a hook, a clamp, or another mechanism configured to hang an IV bag.

[0032] The flow control interface allows a gravity infusion control system to couple with a portion of an IV administration set, form an internal passage for fluid flow, and control the flow of fluid through the internal passage. The flow control interface includes another IV administration set coupler configured to engage or retain a portion of an IV administration set, such as an IV tube, that forms the internal passage.

[0033] refer to Figure 1, shows an embodiment of a gravity infusion control system 100 for use with an IV administration kit coupled to a patient 1. The gravity infusion control system 100 includes a user interface 110, a flow detection interface, and a flow control interface. The flow detection interface includes a first IV administration kit coupler and a second IV administration kit coupler. In addition, the flow control interface includes a third IV administration kit coupler of the gravity infusion control system.

[0034] The gravity infusion control system 100 is coupled to an IV administration set having an IV bag 12 and a drip chamber 14, which are fluidly coupled together by an IV tube 16 extending therebetween. A flow control device 20 is coupled to a section of IV tube 18 extending between the drip chamber 14 and the patient 1. The IV tube is coupled to the patient intravenously via a catheter 22.

[0035] The IV administration kit and gravity infusion control system 100 are arranged with an IV bag 12 coupled to a first IV administration kit coupler, a drip chamber 14 coupled to a second IV administration kit coupler, and a flow control device 120 coupled to a third IV administration kit coupler. After coupling the IV tube 18 of the IV administration kit to the patient, the user interface 110 can be used to initiate an infusion process. Initiating an infusion process can include inputting operating parameters, such as a fluid flow rate of the medical fluid and a volume of the medical fluid to be administered.

[0036] Reference now Figure 2 , shows an embodiment of a gravity infusion control system 200, including a mass change sensor 201 as a flow detection interface, a drip chamber 13, a user interface 110, an IV tube 18, and a roller clamp 140. For example, the mass change sensor 201 can be a weighing sensor or a weight. In some embodiments, the mass change sensor 201 is coupled to the drip chamber 13. The structure that couples the mass change sensor 201 to the drip chamber 13 can be formed as an arm, a hook, a clamp, or another mechanism configured to suspend the drip chamber 13.

[0037] Reference now Figure 3, shows an embodiment of a gravity infusion control system 300, including a mass change sensor 201 as a flow detection interface, a drop detector 301 as a flow sensor, a drip chamber 13, a user interface 110, an IV tube 18, and a roller clamp 140. The gravity infusion control system 300 is similar to the gravity infusion system 200 described above, but with the addition of a drop detector 301. In some embodiments, the drop detector 301 is an infrared light transmitter and receiver. For example, the mass change sensor 201 can be a weighing sensor or a weight. In some embodiments, the mass change sensor 201 is coupled to the drip chamber 13. The structure that couples the mass change sensor 201 to the drip chamber 13 can be formed as an arm, a hook, a clamp, or another mechanism configured to suspend the drip chamber 13.

[0038] The flow sensor may include any sensor for detecting movement or weight changes of a medical fluid reservoir. In some embodiments, the flow sensor may be an optical sensor configured to detect changes in liquid volume in a medical fluid reservoir.

[0039] The gravity infusion control system of the present disclosure can further provide functions that can improve the safety and security associated with drug administration. In some embodiments, the gravity infusion control system can provide a system or subsystem to identify and verify the identity of a patient. The identification and verification of the patient's identity can be performed using a user interface, a scanner, or other device, such as a smart phone that can communicate with a processor of the gravity infusion control system and / or a patient data system. The identification of the patient can include capturing a photographic record of the patient or scanning a bar code on an identification band coupled to the patient.

[0040] Additional features of a gravity infusion control system that can improve safety and security associated with medication administration include the ability to identify tampering with a medication associated with an infusion. The gravity infusion control system can include a weight sensor configured to monitor the weight of a fluid reservoir to also identify tampering with a medical medication.

[0041] The gravity infusion control system of the present disclosure can provide functionality for detecting potential or actual complications associated with the infusion process. In some embodiments, the gravity infusion control system can provide a system or subsystem configured to identify potential complications associated with the fluid pathway, including but not limited to occlusion, air in the fluid pathway, leakage or extravasation of the fluid pathway, and instability in the flow of medical fluid. To detect potential or actual complications, the gravity infusion control system can include sensors such as air-in-line sensors, weight sensors, and / or pressure sensors.

[0042] In some embodiments of the present disclosure, the gravity infusion control system is configured to be coupleable with one or more subsystems or modules, such as an in-line air subsystem, an anti-tamper subsystem, a permeation subsystem, a leak detection subsystem, a pressurization subsystem, and / or a patient data subsystem.

[0043] The gravity infusion control system can provide a workflow with higher efficiency and reliability relative to other infusion systems. The workflow associated with the gravity infusion control system may include, but is not limited to, a preparation phase, a priming phase, an infusion phase, an infusion maintenance phase, and an infusion end phase. It should be understood that one or more phases may occur simultaneously or sequentially.

[0044] In the preparation phase of the workflow, the caregiver can scan the patient's wristband to identify and verify the patient. During the pre-filling phase, the caregiver can place the IV administration kit in the gravity infusion control system and initiate the pre-filling of the fluid pathway. The pre-filling phase can also include indicating that there are no complications, such as air in the fluid pathway, through the gravity infusion control system. During the infusion phase, the caregiver can enter the drip rate and initiate or start the infusion process. The infusion phase or any other phase can initiate the preservation of documentation or data associated with the infusion process. During the infusion maintenance phase, the gravity infusion control system can provide one or more notifications, such as the presence of occlusion, air in the pipeline, tampering, leakage and / or penetration. In addition, during the infusion maintenance phase, the gravity infusion control system can automatically maintain the fluid flow rate. During the end of the infusion phase, the gravity infusion control system can automatically clamp or block the fluid pathway of the IV tube, thereby preventing further delivery of medical fluids or accidental leakage of medical fluids during the disconnection of the IV administration kit from the patient.

[0045] Subject Technology as a Description of the Terms

[0046] For example, the subject technology is shown according to the various aspects described below. For convenience, various examples of various aspects of the subject technology are described as numbered clauses (1, 2, 3, etc.). These are provided only as examples and do not limit the subject technology. It should be noted that any dependent clauses can be combined in any combination and placed in the corresponding independent clauses, such as clause 1 or clause 5. Other clauses can be presented in a similar manner.

[0047] Item 1: A gravity infusion control system comprising: a drip chamber containing an infusate configured to be fluidly coupled to a patient via an IV tube extending therebetween; a mass change sensor configured to detect any one of a change in weight or movement of the infusate in the drip chamber; and a drop detector configured to detect drops of the infusate falling from the drip chamber.

[0048] Clause 2: The gravity infusion control system of clause 1 further comprises a user interface for controlling the flow of the gravity infusion system.

[0049] Clause 3: The gravity infusion control system of clause 1, wherein the mass change sensor is a load cell or a weight.

[0050] Clause 4: The gravity infusion control system of clause 1, wherein the drip chamber is coupled to the mass change sensor via an arm, hook or clamp.

[0051] Clause 5: The gravity infusion control system of clause 1, wherein the infusate fluid flow is directed through the IV tube by gravity pressure.

[0052] Item 6: The gravity infusion control system of Item 1, wherein the droplet detector is an infrared light emitter and receiver.

[0053] Item 7: The gravity infusion control system of Item 5, wherein the infusate fluid flow is configured to provide a flow rate of about 50 mL / hour, about 100 mL / hour, about 150 mL / hour, about 200 mL / hour, about 250 mL / hour, about 300 mL / hour, about 350 mL / hour, about 400 mL / hour, about 450 mL / hour, or about 500 mL / hour.

[0054] Item 8: The gravity infusion control system of Item 5, wherein the infusate fluid flow is configured to provide a flow rate of about 2 mL / hr, about 5 mL / hr, about 10 mL / h, about 15 mL / hr, about 20 mL / hr, about 25 mL / hr, about 30 mL / hr, about 35 mL / hr, about 40 mL / hr, about 55 mL / hr, or about 5 mL / hr.

[0055] Clause 9: The gravity infusion control system of clause 5, wherein the infusate fluid flow is greater than 500 mL / hr.

[0056] Clause 10: The gravity infusion control system of Clause 1 further comprises one or more of an in-line air detector, a leak detector, an external pressure module, an anti-tampering module, an information and control module, and a connection module.

[0057] Clause 11: A gravity infusion control system comprising an intravenous administration set coupled to a medical fluid reservoir and a flow sensor coupled to the intravenous administration set, the gravity infusion control system being configured so that the flow sensor can detect any change in mass or movement of the medical fluid reservoir.

[0058] Clause 12: The gravity infusion control system of clause 11, wherein the flow sensor comprises a mass change sensor and a droplet detector.

[0059] Clause 13: The gravity infusion control system of clause 11, wherein the flow sensor is configured to detect any of a change in weight or a movement of a medical fluid reservoir of the intravenous administration set.

[0060] Clause 14: The gravity infusion control system of clause 12, wherein the mass change sensor is a load cell or a weight.

[0061] Clause 15: The gravity infusion control system of clause 12, wherein the droplet detector is an infrared light emitter and receiver.

[0062] Item 16: A method for providing a gravity infusion control system, comprising coupling a medical fluid reservoir of an intravenous administration kit to a flow sensing interface, wherein the flow sensing interface includes a flow sensor configured to detect any of a mass change or movement of the medical fluid reservoir, selecting a flow rate through the intravenous administration kit using a processor, wherein the processor is connected to the flow sensing interface and the flow control interface such that the processor receives data from the flow sensor to determine the presence of fluid flow through the tubing of the intravenous administration kit.

[0063] Item 17: The method of Item 14, wherein the selected flow rate is about 50 mL / hour, about 100 mL / hour, about 150 mL / hour, about 200 mL / hour, about 250 mL / hour, about 300 mL / hour, about 350 mL / hour, about 400 mL / hour, about 450 mL / hour, or about 500 mL / hour.

[0064] Clause 18: The method of clause 14, wherein the selected flow rate is about 2 mL / hr, about 5 mL / h, about 10 mL / hr, about 15 mL / hr, about 20 mL / h, about 25 mL / h, about 30 mL / h, about 35 mL / h, about 40 mL / h, about 55 mL / h or about 5 mL / h.

[0065] Clause 19: The method of clause 14, wherein the selected flow rate is greater than 500 mL / hr.

[0066] Clause 20: The method of clause 14, wherein the flow sensor comprises a mass change sensor and a droplet detector.

[0067] Further considerations

[0068] In some embodiments, any clause herein may be subordinate to any independent clause or any dependent clause. In one aspect, any clause (e.g., dependent clause or independent clause) may be combined with any other one or more clauses (e.g., dependent clause or independent clause). In one aspect, a claim may include some or all words (e.g., steps, operations, means or parts) narrated in a clause, sentence, phrase or paragraph. In one aspect, a claim may include some or all words narrated in one or more clauses, sentences, phrases or paragraphs. In one aspect, some words of each in a clause, sentence, phrase or paragraph may be deleted. In one aspect, additional words or elements may be added to a clause, sentence, phrase or paragraph. In one aspect, the subject technology may be implemented without utilizing some parts, elements, functions or operations described herein. In one aspect, the subject technology may be implemented utilizing additional parts, elements, functions or operations.

[0069] The present disclosure is provided to enable those skilled in the art to practice the various aspects described herein. The present disclosure provides various examples of the subject technology, and the subject technology is not limited to these examples. Various modifications to these aspects will be apparent to those skilled in the art, and the general principles defined herein may be applied to other aspects.

[0070] Unless otherwise specified, elements presented in the singular do not mean "one and only one" but rather "one or more." Unless otherwise specified, the word "some" refers to one or more. Masculine pronouns (such as his) include feminine and neuter pronouns (such as her and its) and vice versa. Headings and subheadings, if any, are used for convenience only and do not limit the invention.

[0071] The word "exemplary" as used herein means "serving as an example or illustration." Any aspect or design described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other aspects or designs. In one aspect, the various alternative configurations and operations described herein may be considered to be at least equivalent.

[0072] Phrases such as "aspects" do not mean that the aspect is essential to the subject technology, nor do they mean that the aspect applies to all configurations of the subject technology. The disclosure related to an aspect can apply to all configurations, or one or more configurations. An aspect can provide one or more examples. Phrases such as aspects can refer to one or more aspects, and vice versa. Phrases such as "embodiments" do not mean that such embodiments are essential to the subject technology, nor do they mean that such embodiments are applicable to all configurations of the subject technology. The disclosure related to an embodiment can apply to all embodiments, or one or more embodiments. An embodiment can provide one or more examples. Phrases such as embodiments can refer to one or more embodiments, and vice versa. Phrases such as "configurations" do not mean that such configurations are essential to the subject technology, nor do they mean that such configurations are applicable to all configurations of the subject technology. The disclosure related to a configuration can apply to all configurations, or one or more configurations. A configuration can provide one or more examples. Phrases such as configurations can refer to one or more configurations, and vice versa.

[0073] In one aspect, unless otherwise indicated, all measurements, values, ratings, positions, amplitudes, dimensions and other specifications set forth in this specification (including the appended claims) are approximate and not exact. In one aspect, they are intended to have a reasonable range consistent with the functions to which they are related and the customary practices in the art to which they belong.

[0074] In one aspect, the term "coupled" or the like may refer to a direct coupling. In another aspect, the term "coupled" or the like may refer to an indirect coupling.

[0075] The terms "top", "bottom", "front", "back", etc. used in this disclosure should be understood to refer to an arbitrary reference system, not the ordinary gravitational reference system. Thus, the top surface, bottom surface, front surface, and back surface can extend upward, downward, diagonally, or horizontally in the gravitational reference system.

[0076] Various items can be arranged differently (e.g., arranged in different orders, or partitioned in different ways), all of which do not depart from the scope of the subject technology. All structural and functional equivalents of the elements of various aspects described in the entire disclosure known or to be known by a person of ordinary skill in the art are expressly incorporated herein by reference and are intended to be covered by the claims. In addition, regardless of whether such disclosure is explicitly described in the claims, anything disclosed herein is not intended to be dedicated to the public. Any claim element should not be interpreted according to the provisions of the sixth paragraph of 35 U.S.C. § 112, unless the phrase "means for..." is explicitly used to describe the element, or in the case of a method claim, the phrase "step for..." is used to describe the element. In addition, within the scope of using terms such as "include", "have", etc., such terms are intended to be included in a manner similar to the term "comprise", because "include" is interpreted as including when used as a transitional word in the claims.

[0077] The title, background, overview, brief description of the drawings, and abstract of the present disclosure are hereby incorporated into the present disclosure and are provided as illustrative examples of the present disclosure rather than as limiting descriptions. It should be understood when submitted that they will not be used to limit the scope or meaning of the claims. In addition, in the detailed description, it can be seen that the description provides illustrative examples and that various features are grouped together in various embodiments in order to simplify the present disclosure. This method of disclosure should not be interpreted as reflecting an intention that the claimed subject matter requires more features than those explicitly stated in each claim. On the contrary, as reflected in the following claims, the inventive subject matter lies in less than all features of a single disclosed configuration or operation. The following claims are hereby incorporated into the detailed description, and each claim itself exists independently as a separately claimed subject matter.

[0078] The claims are not intended to be limited to the aspects described herein, but rather should be given the full scope consistent with the language of the claims and encompassing all legal equivalents. Nevertheless, no claim is intended to encompass subject matter that does not satisfy the requirements of 35 U.S.C. §101, 102, or 103, nor should they be interpreted in such a manner.

[0079] Example

[0080] Example 1: Droplet Calibration

[0081] It is known that the droplet size through a normal drip chamber (e.g., 20 drops / mL) is affected by the droplet velocity and fluid properties (e.g., density and surface tension). Therefore, it is desirable to determine the droplet size for a specific infusate type and at different velocities. The following scheme provides a method for determining the average droplet weight at different velocities for a given infusate:

[0082] Step 1: Start the Gravity Infusion Control System from the Off Position

[0083] Step 2: The gravity infusion control system opens the flow restriction subsystem to open rate 1 for a specified period of time or a specified number of drops. Rate 1 is intended to be a very slow position (~20 drops per minute). The gravity infusion control system records the drip rate (r1), number of drops (n1), and mass change (dM1)

[0084] Step 3: The gravity infusion control system turns the flow restriction subsystem on to open rate 2 for a specified period of time or a specified number of drops. Rate 2 is intended to be a faster position (~400 drops per minute). The gravity infusion control system records the drip rate (r2), number of drops (n2), and mass change (dM2)

[0085] Step 4: Using the data generated in Steps 2 & 3, the gravity infusion control system can create a linear calibration curve for the infusion fluid. The calibration curve provides the average drop weight at a specific drip rate. This calibration curve is shown in Figure 4 shown. Figures 5A-5C Three different droplet sizes produced at three different droplet rates are shown.

[0086] In principle, the process can be modified to add as many calibration points as desired.

[0087] Example 2: Density Estimation

[0088] This article describes options for estimating the density of infusates.

[0089] Option 1: For a saline-like fluid, assume the fluid density is approximately equal to 0.9% saline (~1.0049 g / mL)

[0090] Option 2: For fluids like saline, assume that the volume of 1 drop at low velocity is 0.05 mL (for a drip chamber of 20 drops per mL). Allow a specified number of drops to pass and measure the mass change (as in step 2 or step 3 of the drop calibration). Density = (mass change) / [(number of drops) * (0.05 mL)]

[0091] Option 3: Store a library of fluid densities on the gravity infusion control system. When the nurse scans a medication or enters a medication type, the gravity infusion control system selects the appropriate density value.

[0092] Example 3: Normal Infusion

[0093] Normal infusion is approximately 50-500 mL / hour. Two options for sensing flow during a normal infusion are provided below. Figure 6 is a graph showing an example of an infusion rate of 200 mL / hr.

[0094] Option 1. Mass change as the primary factor: During normal infusion, flow rate can be sensed by the change in mass over time divided by an assumed or given fluid density.

[0095] Option 2. Calibrated drops as primary factor: During normal infusion, flow can be sensed by counting the number of drops and adjusting their assumed mass based on a linear calibration curve and an assumed or given fluid density.

[0096] Example 4: Keeping the vein open (KVO) infusion

[0097] KVO infusion is typically 2-50 mL / hr. In principle, KVO infusion control can be similar to normal infusion as described, except for the following challenges:

[0098] 1. At KVO rates, the time between drops becomes very long (1-2 minutes between drops), making the response time for the system to reach the correct flow very long if based on the drip rate.

[0099] 2. The signal-to-noise ratio of the mass change sensor becomes very large because the mass change is very small, causing noise effects such as drift to have a more significant impact on the change in total mass over time. Figure 7 shown.

[0100] To overcome these challenges during KVO infusion, the change in mass signal is used to create the initial rate set point, since changes in mass are detectable as droplets form. This approach results in a radically faster response time than relying solely on a drop counter. Additionally, a drop counter is used to track the total volume during the KVO infusion, since drop counters are less susceptible to drift and other potential effects than mass change sensors.

[0101] In this way, the two sensors work together, in theory, to enable a gravity-fed infusion control system to reach the desired flow rate more quickly and to provide an accurate measurement of the total volume infused during a KVO infusion.

[0102] Example 5: Rapid Infusion

[0103] Rapid infusions are usually greater than 500 mL / hr. Figure 8 is a graph showing an example of a bolus infusion rate. In principle, bolus infusion control can be similar to normal infusion as described, except for the following challenges:

[0104] The droplets begin to coalesce together into a steady stream, and the droplet sensor is no longer effective in measuring volume changes over time.

[0105] To overcome this challenge during rapid infusions, a mass change sensor is made the primary sensor for measuring flow (option 1 for normal infusions). For these rates, the change in mass will be very large relative to the noise effects.

[0106] Example 6: Mechanical Noise on a Load Cell

[0107] The mass change sensor is sensitive to events such as drift, environmental vibration, shock or collision to the IV pole, movement of the IV pole (during transport or walking), possible line tension (for example, during setup, the clinician may inadvertently connect the IV set, thereby increasing line tension and creating a steady external force on the mass change sensor), and other similar events.

[0108] If a gravity infusion control system encounters these events, the primary means of detecting flow can be temporarily or permanently switched from Option 1 (mass change as the primary factor) to Option 2 (calibrated drop count as the primary factor).

[0109] Example 7: Theft or leakage of infusion fluid

[0110] If the flow rate determined by option 1 (mass change as the main factor) is significantly greater than the flow rate determined by option 2 (calibrated droplets as the main factor), it can be inferred that a major leak or possible theft of the infusate has occurred. Fig. 9 Potential access points for infusate theft are shown.

Claims

1. A gravity infusion control system, comprising: a drip chamber containing an infusion configured to be fluidly coupled to a patient via an IV tube extending therebetween; a mass change sensor configured to detect any one of a change in weight or a movement of the infusion fluid in the drip chamber; as well as A drop detector is configured to detect a drop of the infusion fluid falling from the drip chamber.

2. The gravity infusion control system of claim 1, further comprising a user interface for controlling the flow rate of the gravity infusion control system.

3. The gravity infusion control system according to claim 1, wherein: The mass change sensor is a load cell or a weight.

4. The gravity infusion control system according to claim 1, wherein: The drip chamber is coupled to the mass change sensor via an arm, hook or clamp.

5. The gravity infusion control system according to claim 1, wherein: The infusate fluid flow is directed through the IV tubing by gravity pressure.

6. The gravity infusion control system according to claim 1, wherein: The droplet detector is an infrared light emitter and receiver.

7. The gravity infusion control system according to claim 5, wherein: The infusate fluid flow is configured to provide a flow rate of about 50 mL / hour, about 100 mL / hour, about 150 mL / hour, about 200 mL / hour, about 250 mL / hour, about 300 mL / hour, about 350 mL / hour, about 400 mL / hour, about 450 mL / hour, or about 500 mL / hour.

8. The gravity infusion control system according to claim 5, wherein: The infusate fluid flow is configured to provide a flow rate of about 2 mL / hr, about 5 mL / hr, about 10 mL / hr, about 15 mL / hr, about 20 mL / hr, about 25 mL / hr, about 30 mL / hr, about 35 mL / hr, about 40 mL / hr, about 55 mL / hr or about 5 mL / hr.

9. The gravity infusion control system according to claim 5, wherein: The infusate fluid flow is greater than 500 mL / hr.

10. The gravity infusion control system of claim 1, further comprising one or more of an in-line air detector, a leak detector, an external pressure module, an anti-tamper module, an information and control module, and a connection module.

11. A gravity infusion control system, comprising: an intravenous administration kit coupled to a medical fluid reservoir; as well as A flow sensor is coupled to the intravenous administration set, the gravity infusion control system being configured such that the flow sensor can detect any mass change or movement of the medical fluid reservoir.

12. The gravity infusion control system of claim 11, wherein: The flow sensor includes a mass change sensor and a drop detector.

13. The gravity infusion control system of claim 11, wherein: The flow sensor is configured to detect any of a change in weight or a movement of the medical fluid reservoir of the intravenous administration set.

14. The gravity infusion control system of claim 12, wherein: The mass change sensor is a load cell or a weight.

15. The gravity infusion control system of claim 12, wherein: The droplet detector is an infrared light emitter and receiver.

16. A method for providing a gravity infusion control system, comprising: coupling a medical fluid reservoir of an intravenous administration kit to a flow detection interface, wherein the flow detection interface includes a flow sensor configured to detect any one of a mass change or a movement of the medical fluid reservoir; A flow rate through the IV set is selected using a processor, wherein the processor is coupled to the flow sensing interface and the flow control interface such that the processor receives data from the flow sensor to determine the presence of fluid flow through tubing of the IV set.

17. The method according to claim 14, wherein: The selected flow rate is about 50 mL / hour, about 100 mL / hour, about 150 mL / hour, about 200 mL / hour, about 250 mL / hour, about 300 mL / hour, about 350 mL / hour, about 400 mL / hour, about 450 mL / hour, or about 500 mL / hour.

18. The method according to claim 14, wherein: The selected flow rate is about 2 mL / hr, about 5 mL / hr, about 10 mL / hr, about 15 mL / hr, about 20 mL / hr, about 25 mL / hr, about 30 mL / hr, about 35 mL / hr, about 40 mL / hr, about 55 mL / hr or about 5 mL / hr.

19. The method according to claim 14, wherein: The selected flow rate is greater than 500 mL / hr.

20. The method according to claim 14, wherein: The flow sensor includes a mass change sensor and a drop detector.

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