The present invention relates to the infusion of fluid into a patient, and more particularly relates to a device, system and method for administration of infusions and infusion monitoring.
Infusion is the administration of a fluid-based substance into a patient, most typically this is performed directly into the venous side of the patient's vascular system but can also be performed into the arterial side of the patient's vascular system or into the subcutaneous tissue and not directly into the vascular system. For purposes of the description of the present invention, infusion shall mean any or all of the possible methods of administering fluid-based substances into a patient. The variety of aspects and embodiments of the present invention apply to all forms of infusion.
The simplest form of infusion is a syringe coupled to a hollow needle or catheter, commonly referred to as an injection. The needle is inserted through the skin into a vein, and the contents of the syringe are injected through the needle into the bloodstream. Generally, the most accessible veins are the metacarpal veins in the forearm of a patient. Typically, a tourniquet is applied to restrict the flow of blood, thus causing the veins to bulge. The needle is then inserted through the skin and into the vein and the tourniquet is removed. After the needle is inserted, it is common to draw back slightly on the syringe to see a blood return, thus verifying that the needle is within the vein and not the surrounding tissue.
Some syringes, as shown in
Infusion can be intermittent or continuous; continuous administration is most often performed directly into one of the patient's veins and is referred to as an intravenous infusion. An intravenous infusion consists of a needle or a catheter, inserted through the skin into a venous system commonly, but not always, into a peripheral vein. A peripheral vein is any vein that is not in the chest or abdomen. Part of the needle or catheter remains outside the skin, with a hub that can be connected to a syringe or an intravenous infusion line, or capped. An infusion pump may be used to provide precise control over the flow rate and total amount passed through the infusion line.
Various adverse effects can be caused by improper location of the needle or catheter within the vein or surrounding tissue, as shown in
Regular monitoring of infusion sites helps reduce the severity of adverse effects when infiltration and extravasation occurs. Based on the foregoing, it is apparent that there is a need for an automated device, system, and method for administration of infusions that provide regular monitoring of infusions.
The present invention provides a device, system, and method for monitoring infusion of fluids into a patient. The present invention may be used for either intermittent or continuous, manual or automatic infusion monitoring. The present invention may also be used while infusing a variety of medications and fluids, both vesicant and non-vesicant compounds, into a patient. The present invention may have an integral needle or catheter for infusing fluids into the patient, may operate with the addition of a standard needle or catheter familiar to those skilled in the art, or may be integrated into and/or with components forming a larger more comprehensive system.
One or more sources of fluid may connect to the proximal end of the infusion monitoring device and allow gravity “drip” type of intravenous delivery or a mechanized “pump” infusion type of delivery. The fluid flows from the source through the infusion monitoring device through the needle or catheter into the patient.
The infusion monitoring device may include a pad or other similar “region” or “features” for securing the infusion monitoring device to the patient. One skilled in the art will appreciate that this can be provided by various means such as having a self-adhesive area for allowing the infusion monitoring device to be adhered to the skin of a patient to maintain the device in place.
The infusion monitoring device also includes a variable volume chamber, which may exist in one or more forms, any or all of which will be collectively referred to herein as a variable volume chamber. The primary purpose of the variable volume chamber is to provide a method to create a negative pressure differential between the infusion monitoring device and the patient so that fluid will be drawn from the patient at the infusion site and into the infusion monitoring device for observation. The variable volume chamber is in fluidic connection with the needle or catheter. The variable volume chamber is designed and constructed such that it's volume can be increased or decreased which allows the volume of fluid contained in the intravenous injection monitoring device to increase or decrease. In one embodiment, the volume or capacity of the variable volume chamber is typically sized to match the size and volume of the catheter/needle and other fluid coupling between the variable volume chamber and the patient.
The infusion monitoring device also contains a fluid valve to interrupt and resume the flow of fluid between the infusion fluid supply and the patient and is placed between the fluid source and the variable volume chamber. One skilled in the art will appreciate that the fluid valve may be accomplished by a wide variety of means common in devices that control the flow of medical and other fluids. One skilled in the art will also appreciate that the valve may be normally closed or normally open, and may or may not require power to stay in either the open or closed position.
An optional actuator may be located in the infusion monitoring device and coupled to the variable volume chamber, for causing the variable volume chamber to expand thereby creating a negative pressure or negative pressure gradient in the injection fluid line coupled to the patient, or contract creating a positive pressure or positive pressure gradient in the injection fluid line coupled to the patient. With a fluid valve closing the path between the infusion monitoring device and the fluid supply, a negative pressure or negative pressure gradient creates a tendency for fluid from the patient to be drawn proximally through the needle or catheter into the infusion monitoring device. One skilled in the art will appreciate that the actuator may derive its motive power from screws, drive wheels, levers, pneumatic connections, fluid connections, gravity, or direct human touch, any or all of which may cause the variable volume to expand or contract. The variable volume chamber may also be actively actuated to change its volume, and then return to its original volume without active actuation. The volume of fluid in the variable volume chamber may also change as a result of the pressure in the venous system of the patient either in combination with an actuator or without the need for an actuator, as well as with or without the need for a vent.
A fluid inspection window is typically located distally to the variable volume chamber that is, between the variable volume chamber and the patient, in order to view and monitor the injection fluid within the infusion monitoring device. The window may be a clear component, positioned to allow the administrator to directly, visually view and monitor the fluid within the infusion monitoring device. Alternatively or in addition, a sensor may either replace the window or be located in proximity to the window, for sensing the presence, composition or characteristics of the fluid within the infusion monitoring device. One skilled in the art will appreciate that a variety of sensors or sensor type devices may be used to determine various conditions such as the presence, absence, composition, characteristic, flow rate or even temperature of the fluid. Such sensors include, but are not limited to ultrasonic sensors, light sensors, optical sensors, and cameras or probes of various types. The sensors or sensor type devices may perform their function with or without contacting the fluid. The sensing may also occur with the addition of a chemical marker or reagent that is added to the fluid and may or may not be removed from the infusion monitoring device for further processing.
The infusion monitoring device, system and method of the present invention allows the administrator to periodically monitor the administration of a fluid based substance to determine that the needle or catheter is in the correct position within the patient. If the distal end of the needle or catheter is not in a vein, when the infusion monitoring device draws fluid from the patient, no blood will be present in the window. The presence or absence of blood in the window may or may not be desirable depending on where the needle or catheter is supposed to be located in the patient.
The presence, composition or characteristics of the fluid in the window when the infusion monitoring device draws fluid from the patient may be viewed directly by an administrator who is present, or by a sensor that provides a signal or alarm. The signal or alarm provided by the sensor may be communicated directly by the infusion monitoring device in the form of any combination of visual, auditory or electronic indicators or remotely to one or more devices that provide any combination of visual, auditory or electronic indicators that may be present at or near the patient, or may be present at a remote location such as a nursing station. The signal or alarm provided by the sensor may be communicated from the infusion monitoring system remotely through a wire or by a wireless connection.
The infusion monitoring system may or may not provide for programming various functions or functionalities of the infusion monitoring device. Examples of user programmability include, but are not limited to: the inspection times, intervals or periods; alarm trigger thresholds; what is to be recorded; how long is recorded information to be kept; reporting format, criterion and frequency; and acceptable range of sensor values. The infusion monitoring device may or may not control, or cause to limit, or allow for the setting of limits on the volume of fluid drawn from the patient as well as setting limits on the pressure created to draw fluid from, or deliver fluid to the patient.
The infusion monitoring system may or may not have the capability to provide a back and forth fluid flow (reciprocating cycle) at the distal end of the needle or catheter. This flow can be used to prevent blood from clotting at or near the end of the needle or catheter that would occlude the fluid pathway to the patient.
The present invention contemplates several embodiments of the infusion monitoring device and system of the present invention.
In the first embodiment of the present invention, the infusion monitoring device is a simple manual device to expedite a manual, visual check. A single or multiple user actions may occlude the line and attempt to draw fluid from the patient for visual inspection.
In another embodiment of the present invention, which may be entitled the basic automated device, a battery powered infusion monitoring system checks for the presence, composition or characteristics of the fluid at a predetermined interval and sounds an alarm and/or occludes the line if an infiltration or other anomalous condition exists, without remote connections. The goal of this device is to add automation to the task in the most simple way possible. This method may or may not allow manual inspections (manual override or one-touch operation). It is contemplated that this method of operation could include a range of devices that may be preset for different inspection intervals, pressures, volumes, acceptable range of sensor values, etc. This may be able to be done without software, which would greatly reduce the system complexity and regulatory requirements.
In a further embodiment of the present invention, the infusion monitoring device may be operated as a programmable device with user adjustable settings for inspection frequency, fluid pressures, volumes, acceptable range of sensor values, etc.
In yet another embodiment of the present invention, the infusion monitoring system may record and/or report the current state and history of inspections and alarms to the clinician either locally or remotely by wired or wireless transmission.
In a further contemplated embodiment of the present invention, the infusion monitoring device may be integrated with one or more other patient care devices such as those for infusion, patient monitoring, diagnostics or any other purpose. The infusion monitoring device of the present invention may operate cooperatively with these devices by sharing a power source, a user interface, alarm enunciation, control commands, data storage, or the like.
In a further contemplated embodiment of the present invention, the infusion monitoring system may monitor certain characteristics of the infusate such as ensuring that the fluid source is still providing a fluid (bag not empty); that the fluid is the correct fluid; that the fluid rate and/or temperature are as expected, and other such monitoring.
In a further contemplated embodiment of the present invention, the infusion monitoring system may monitor certain properties or characteristics of the patient's blood beyond the mere presence of blood. These properties or characteristics may include blood glucose, oxygen saturation, or any number of other properties or characteristics, that can be evaluated in situ via the window within the primary fluid path. These properties or characteristics may also include any number of other properties or characteristics that must be evaluated external to the primary flow of the device in which case the blood or fluid may be withdrawn and/or re-directed from the fluid path to be analyzed.
In any of the previously mentioned embodiments, all or part or none of the infusion monitoring device may be disposable and intended for a single use while all or part or none of the device may be reused.
Although the present invention is described in connection with one or more exemplary embodiments, any of which may be used alone or combined in whole or in part with other disclosed embodiments, this is not a limitation of the present invention which is not to be limited except by the allowed claims and their legal equivalents.
These and other features and advantages of the present invention will be better understood by reading the following detailed description, taken together with the drawings wherein:
The infusion monitoring device 15,
The infusion monitoring device 15 according to the present invention also includes a window 20 typically located between the variable volume chamber 14 and the patient 18, to allow a user, either directly or with the use of a sensor 30, to determine and/or monitor the presence, properties or characteristics of the fluid within the infusion monitoring device.
During infusion, fluid flows from the infusion supply 16 through the infusion monitoring device 15 through the catheter or needle 22 into the patient 18.
An actuator 26, which may be manual or automatic, may optionally be located in the infusion monitoring device 15 and coupled to the variable volume chamber 14, for causing the variable volume chamber 14 to expand or to contract.
With a fluid valve 12 closing the path between the infusion monitoring device 15 and the injection fluid supply 16, a pressure gradient, caused by expanding the variable volume chamber 14 and/or venous pressure in the patient's system, creates a tendency for fluid from the patient 18 to flow proximally through the needle or catheter 22 into the infusion monitoring device 15 due to the pressure differential in the line between the patient 18 and the infusion monitoring device 10 and with or without the use of a vent 27.
The presence or absence of blood in the window 20 may or may not be desirable depending on where the needle/catheter 22 is supposed to be located in the patient 18. For example, if the needle/catheter 22 is supposed to be in the patient's venous system, then blood should be present in a window 20 when the infusion monitoring device 15 of the present invention draws fluid from the patient. Alternatively, if the needle/catheter 22 is not supposed to be positioned in the patient's venous system, the presence of blood in the window 20 would indicate that the needle/catheter 22 is positioned incorrectly. Those skilled than the art will understand and appreciate how the infusion monitoring system 10 according to the present invention may be utilized as described herein.
The present invention contemplates that the valve 12, variable volume chamber 14, actuator 26 and window 20 may be integrated to form a device hereinafter referred to as the “simple manual device” 15 that may or may not also include a vent 27 and needle or catheter 22. It is further contemplated that the infusion monitoring system 10 of the present invention may include additional elements and functionality to automate the sensing and reporting of the presence, properties, composition or characteristics of the fluid in the infusion monitoring device 15 as will be described below in connection with a system.
In the present invention, the presence, properties or characteristics of the fluid in the infusion monitoring system 10 may be determined by the administrator or by a sensor 30 that provides a signal or alarm 32 to indicate the readings of the sensor and/or the presence of a potential problem.
The infusion monitoring system 10 may be powered by a battery 36 (AC current—not shown) or be powered by some other source via a remote connection 34.
The infusion monitoring system 10 may include a user interface 42 to allow for programming and other information input and output that may be desired. The user interface 42 may be accessed either locally or by wired or wireless transmission 34.
The infusion monitoring system 10 may have the addition of the ability to record 44 and/or report 34 the current state and history of inspections to the clinician either locally or by wired or wireless transmission 34.
The signal or alarm 32 provided by the sensor 30 may be communicated directly by the infusion monitoring device in the form of any combination of visual, auditory or electronic indicators. The signal or alarm 32 provided by the sensor 30 may be communicated from the infusion monitoring device remotely 34 to one or more devices that provide any combination of visual and auditory indicators that may be present at or near the patient, or may be present at a remote location such as a nursing station. The signal or alarm 32 provided by the sensor 30 may be communicated from the infusion monitoring device remotely 34 through a wire or by a wireless transmission.
It is further contemplated that the alarm 32, remote connection 34, battery 36, user interface 42 and recorder 44 may be integrated to form a device 40 hereinafter referred to as the “controller” 40 to connect with or to the simple manual device 15. The controller 40 may include a memory, processor and user inputs and outputs as described herein. It is further contemplated that the controller 40 may be a separate, stand-alone device or may be part of or incorporated with the simple manual device 15 to form the infusion monitoring system 10.
It is further contemplated that the simple manual device 15 and/or controller 40 may be operated in connection with or integrated with other patient care devices such as those for infusion (infusion pumps for example), patient monitoring, diagnostics or any other purpose via remote connection 34.
Contemplated physical embodiments of the infusion monitoring device 15 according to the invention are shown in
The infusion monitoring device may also provide a shaped or flat adhesive surface 46,
The series of acts 100,
The infusion monitoring system 10 waits for a predetermined or programmed time, act 106.
The next action, 108, determines if there is a signal from the optical sensor determining a change in the fluid in the “window” (i.e. there is or is not blood in the window depending on what the device is looking for), act 108.
If act 108 is “yes”, branch 109 is followed and valve 12 is opened, act 110, and the infusion is continued, act 112. The variable volume chamber 14 returns to its original state and forces fluid back through the needle of catheter 22 into the patient's vein. The infusion of fluid from the supply continues until another specified check of the infusion.
If act 108 determines that there is no signal from the optical sensor or a manual determination of no change in the fluid in the “window” (i.e. there is something other than blood in the window), the “no” branch 114 is taken, and an alarm may be sounded and additional actions may be put into motion, act 116, and may include the occlusion algorithm,
The occlusion algorithm,
According to another aspect of the present invention, the system may be operated in an embodiment to keep the infusion needle or catheter open (referred to herein as KVO). The KVO algorithm,
Although the present invention has been described in connection with one or more exemplary embodiments, any of which may be used alone or combined in whole or in part with other disclosed embodiments, this is not a limitation of the present invention which is not to be limited except by the allowed claims and their legal equivalents. In addition, modifications and substitutions by one of ordinary skill in the art are considered to be within the scope of the present invention.
This application is a divisional of prior U.S. patent application Ser. No. 11/436,110, filed May 17, 2006, which is related to and claims priority from U.S. Provisional Application No. 60/682,527, filed May 17, 2005, entitled Intravenous Detection System which are both incorporated fully herein by reference.
Number | Date | Country | |
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60682527 | May 2005 | US |
Number | Date | Country | |
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Parent | 11436110 | May 2006 | US |
Child | 13373781 | US |