Patent Application
20210038799
This application relates generally to systems and methods for facilitating contact-minimized (or hands-free) connection of medical device tubing, particularly tubing used with home dialysis machines.
Medical devices such as dialysis machines are known for use in the treatment of renal disease. The two principal dialysis methods are hemodialysis (HD) and peritoneal dialysis (PD). During hemodialysis, the patient's blood is passed through a dialyzer of a hemodialysis machine while also passing dialysate through the dialyzer. A semi-permeable membrane in the dialyzer separates the blood from the dialysate within the dialyzer and allows diffusion and osmosis exchanges to take place between the dialysate and the blood stream. During peritoneal dialysis, the patient's peritoneal cavity is periodically infused with dialysate, or dialysis solution. The membranous lining of the patient's peritoneum acts as a natural semi-permeable membrane that allows diffusion and osmosis exchanges to take place between the solution and the blood stream. Automated peritoneal dialysis machines, also called PD cyclers, are designed to control the entire peritoneal dialysis process so that it can be performed at home, usually overnight, without clinical staff in attendance. Both HD and PD machines may include displays with touch screens or other user interfaces that display information of a dialysis treatment and/or enable an operator or patient to interact with the machine.
Dialysis machines may have a disposable set which has several connectors and tubing, also referred to herein as “lines,” used in connection with the dialysis treatment and through which medical fluid flows during the dialysis treatment. Home dialysis patients are required to make multiple tubing connections in the process or setting up their home dialysis machine. These tubing connections are usually made with a Luer Lock connector, having male and female compatible components, and involves twisting the tubing a quarter turn to make a clean and secure connection between tubing paths, for example, to and from disposable sets, solution bags, the patient, and a drain line.
It is important that the connectors not touch dirty surfaces and become contaminated. One of the most common medical risks faced by PD patients is infection in the form of peritonitis. Peritonitis typically occurs due to a “failure” of aseptic technique when a surface of a tubing connector handled by the patient comes in contact with a non-sterile surface. Such surfaces may include the patient's hands (if not properly cleaned), the patient's clothing, or various household objects.
A related challenge for some patients is that it can be difficult to connect tubes without increased risk of failure of aseptic technique. Underlying causes of these challenges include the fact that some patients may have tremors due to comorbidities, such as Parkinson's disease or incipient tremor, or that some patients may be handicapped with impaired use of one hand (e.g., due to arthritis or stroke) or no use of one hand (e.g., due to stroke, amputation etc.). Still other patients have issues with peripheral neuropathy leading to numbness or pain in their extremities. All of these issues can impact effectiveness of aseptic technique, and they can also lead to connections that are not entirely snug, with potential for leaks. For example, Luer Lock type connections that require twisting may be a difficult maneuver for patients with dexterity issues. This is because one hand must tightly grip on side of the tubing connection while the other hand must tightly grip the other side of the tubbing connection and make a one-quarter turn twisting motion. If the connector is not twisted enough or if the tubing on the connector is twisted such that it untwists its own connector, it will leak fluid out or leak air into the system, exposing the patient to spill hazards or air embolism. If the tubing is over-torqued, disconnecting the tubing may become a source of frustration.
One existing solution by which challenges in facilitating and maintaining aseptic technique has been addressed is the stay-safe® organizer, a device developed and distributed by Fresenius Medical Care. The organizer permits a PD user to place one end of a tubing connector into a holder thus enabling them to make connections using only one hand while one side of the tubing is held stationary in the organizer. That said, patients who have tremor and other issues are still subject to potential unintentional touching of connector surfaces because they still must use a hand to unscrew and attach the connectors, and when they move the tubing segments together with the intent of connecting them, at this point there is risk of unintentional touch contamination. It is also noted that organizer is designed for use with particular types of connection components.
Accordingly, it would be desirable to provide a system that addresses the issues noted above, including issues of inadvertent failure of aseptic technique via touch contamination and the challenges faced by patients/users who have mobility impairments impacting effective use of one or more hands.
According to the system described herein, a tubing connection device comprises a first tubing holder that receives a first tubing connector and a second tubing holder that is movable and receives a second tubing connector that is connectable to the first tubing connector. A drive mechanism drives movement of the second tubing holder toward the first tubing holder and drives a motion of the second tubing holder that enables connection of the first tubing connector with the second tubing connector after contact of the first tubing connector and the second tubing connector. The drive mechanism further includes a torque controller that controls an amount of torque that is exerted between the first tubing connector and the second tubing connector when the first tubing connector and the second tubing connector are in contact with each other and engaged in a connection operation. In various implementations, the drive mechanism may include a mechanically actuated drive mechanism and/or a motor driven drive mechanism. The second tubing holder may be driven in a rotation motion to enable connection of the first tubing connector and the second tubing connector. The first tubing holder may include an automatic grip device that automatically grips the first tubing connector. The automatic grip device may include a motor, a processor and at least one sensor, and data from the at least one sensor may be used by the processor to control, via the motor, a gripping action of the automatic grip device of the first tubing connector. The sensor may include one or more of a touch sensor, an optical sensor and/or a voice-actuated sensor. The first tubing connector and the second tubing connector may be compatible Luer Lock connectors.
According further to the system described herein, a dialysis tubing connection system comprises a first tubing set having a first tubing connector, a disposable tubing set that is couplable to a dialysis machine and that includes a second tubing connector, and a tubing connection device. The tubing connection device comprises a first tubing holder that receives a first tubing connector and a second tubing holder that is movable and receives a second tubing connector that is connectable to the first tubing connector. A drive mechanism drives movement of the second tubing holder toward the first tubing holder and drives a motion of the second tubing holder that enables connection of the first tubing connector with the second tubing connector after contact of the first tubing connector and the second tubing connector. The drive mechanism further includes a torque controller that controls an amount of torque that is exerted between the first tubing connector and the second tubing connector when the first tubing connector and the second tubing connector are in contact with each other and engaged in a connection operation. In various implementations, the drive mechanism may include a mechanically actuated drive mechanism and/or a motor driven drive mechanism. The second tubing holder may be driven in a rotation motion to enable connection of the first tubing connector and the second tubing connector. The first tubing holder may include an automatic grip device that automatically grips the first tubing connector. The automatic grip device may include a motor, a processor and at least one sensor, and data from the at least one sensor may be used by the processor to control, via the motor, a gripping action of the automatic grip device of the first tubing connector. The sensor may include one or more of a touch sensor, an optical sensor and/or a voice-actuated sensor. The first tubing connector and the second tubing connector may be compatible Luer Lock connectors.
According further to the system described herein, a method for facilitating tubing connections comprises positioning a first tubing connector in a first tubing holder and positioning a second tubing connector in a second tubing holder that is movable. The method further comprises driving, via a driving mechanism, movement of the second tubing holder toward the first tubing holder, and driving, via the driving mechanism, a motion of the second tubing holder that enables connection of the first tubing connector with the second tubing connector after contact of the first tubing connector and the second tubing connector. The method further comprises controlling, via a torque controller, an amount of torque that is exerted between the first tubing connector and the second tubing connector when the first tubing connector and the second tubing connector are in contact with each other and engaged in a connection operation. The second tubing connector may be a connector at an end of a disposable tubing set that is couplable to a dialysis machine.
Embodiments and features of the system described herein are explained with reference to the several figures of the drawings, which are briefly described as follows.
The system described herein provides for a device by which patients or others seeking to make connections between tubing sets, particularly for a home medical device, can make those connections without having to hold each tube in each hand or, in some implementations, without having to touch any tube during the time of attachment. The system provides for facilitating a consistent secure connection of the tubing connectors.
Dialysate bags 122 may be suspended from the sides of the cart 104, and a heater bag 124 may be positioned in the heater tray 116. Hanging the dialysate bags 122 may improve air management as any air is disposed by gravity to a top portion of the dialysate bag 122. Valves may be attached to a bottom portion of the dialysate bags 122 so fluid is drawn out and air delivery is minimized. Dialysate from the dialysate bags 122 may be transferred to the heater bag 124 in batches. For example, a batch of dialysate may be transferred from the dialysate bags 122 to the heater bag 124, where the dialysate is heated by the heating element. When the batch of dialysate has reached a predetermined temperature (e.g., approximately 98°-100° F., 37° C.), the batch of dialysate may be flowed into the patient. The dialysate bags 122 and the heater bag 124 may be connected to the cartridge via dialysate bag lines 126 and a heater bag line 128, respectively. As illustrated, for example, each bag line, such as a dialysate bag line 126, may include a disposable tubing and connector set 126a coupled to a bag tubing and connector set 126b. The dialysate bag lines 126 may be used to pass dialysate from dialysate bags 122 to the cartridge during use, and the heater bag line 128 may be used to pass dialysate back and forth between the cartridge and the heater bag 124 during use. In addition, a patient line 130 and a drain line 132 may be connected to the cartridge. The patient line 130 may be connected to a patient's abdomen via a catheter and may be used to pass dialysate back and forth between the cartridge and the patient's peritoneal cavity during use. The drain line 132 may be connected to a drain or drain receptacle and may be used to pass dialysate from the cartridge to the drain or drain receptacle during use.
The touch screen 118 and the control panel 120 may allow a user to input various treatment parameters to the dialysis machine 102 and to otherwise control the dialysis machine 102. In addition, the touch screen 118 may serve as a display. The touch screen 118 may function to provide information to the patient and the operator of the PD system 100. For example, the touch screen 118 may display information related to a dialysis treatment to be applied to the patient, including information related to a prescription. In various embodiments, the control panel 120 may also include audio and video component capabilities, including speakers, microphones and/or cameras.
The dialysis machine 102 may include a processing module 101 that resides inside the dialysis machine 102, the processing module 101 being configured to communicate with the touch screen 118 and the control panel 120. The processing module 101 may be configured to receive data from the touch screen 118 the control panel 120 and sensors, e.g., temperature and pressure sensors, and control the dialysis machine 102 based on the received data. For example, the processing module 101 may adjust the operating parameters of the dialysis machine 102.
The dialysis machine 102 may be configured to connect to a network 110. The connection to network 110 may be via a wireless connection, or in some cases a wired connection, as further discussed elsewhere herein. The dialysis machine 102 may include a connection component 111 configured to facilitate the connection to the network 110 along with the processing module 101. The connection component 111 may be a transceiver for wireless connections and/or other signal processor for processing signals transmitted and received over a wired connection. In the case of a wired connection, the connection component 111 may be a port enabling a physical connection to a network component, such as a network modem. Other medical devices (e.g., other dialysis machines) or components may be configured to connect to the network 110 and communicate with the dialysis machine 102.
Although the present disclosure is discussed herein principally in connection with a peritoneal dialysis machine, the system described herein may be used and implemented in connection with other configurations of PD machines, as well as other types of medical devices, including home hemodialysis machines, that require tubing connections.
The cassette interface 109 includes a surface having holes formed therein. The PD machine 102 includes pistons 133A, 133B with piston heads 134A, 134B attached to piston shafts (not explicitly shown). The piston shafts can be actuated to move the piston heads 133A, 133B axially within piston access ports 136A, 136B formed in the cassette interface 109. The pistons 133A, 133B are sometimes referred to herein as pumps. In some embodiments, the piston shafts can be connected to stepper motors that can be operated to move the pistons 133A, 133B axially inward and outward such that the piston heads 134A, 134B move axially inward and outward within the piston access ports 136A, 136B. The stepper motors drive lead screws, which move nuts inward and outward on the lead screws. The stepper motors can be controlled by driver modules. The nuts, in turn, are connected to the piston shafts, which cause the piston heads 134A, 134B to move axially inward and outward as the stepper motors drive the lead screws. Stepper motor controllers provide the necessary current to be driven through the windings of the stepper motors to move the pistons 133A, 133B. The polarity of the current determines whether the pistons 133A, 133B are advanced or retracted. In some embodiments, to the stepper motors require 200 steps to make a full rotation, and this corresponds to 0.048 inches of linear travel of the piston heads 134A, 134B.
In some embodiments, the PD system 100 also includes encoders (e.g., optical quadrature encoders) that measure the rotational movement and direction of the lead screws. The axial positions of the pistons 133A, 133B can be determined based on the rotational movement of the lead screws, as indicated by feedback signals from the encoders. Thus, measurements of the position calculated based on the feedback signals can be used to track the position of the piston heads 134A, 134B of the pistons 133A, 133B.
When the cassette 112 is positioned within the cassette compartment 114 of the PD machine 102 with the door 108 closed, the piston heads 134A, 134B of the PD machine 102 align with the pump chambers 138A, 138B of the cassette 112 such that the piston heads 134A, 134B can be mechanically connected to dome-shaped fastening members of the cassette 112 overlying the pump chambers 138A, 138B. As a result of this arrangement, movement of the piston heads 134A, 134B toward the cassette 112 during treatment can decrease the volume of the pump chambers 138A, 138B and force dialysate out of the pump chambers 138A, 138B. Retraction of the piston heads 134A, 134B away from the cassette 112 can increase the volume of the pump chambers 138A, 138B and cause dialysate to be drawn into the pump chambers 138A, 138B.
The cassette 112 also includes pressure sensor chambers 163A, 163B. When the cassette 112 is positioned within the cassette compartment 114 of the PD machine 102 with the door 108 closed, pressure sensors 151A, 151B align with the pressure sensor chambers 163A, 163B. Portions of a membrane that overlies the pressure sensor chambers 163A, 163B adhere to the pressure sensors 151A, 151B using vacuum pressure. Specifically, clearance around the pressure sensors 151A, 151B communicates vacuum to the portions of the cassette membrane overlying the pressure sensing chambers 163A, 163B to hold those portions of the cassette membrane tightly against the pressure sensors 151A, 151B. The pressure of fluid within the pressure sensing chambers 163A, 163B causes the portions of the cassette membrane overlying the pressure sensor chambers 163A, 163B to contact and apply a force to the pressure sensors 151A, 151B. The pressure sensors 151A, 151B can be any sensors that are capable of measuring the fluid pressure in the pressure sensor chambers 163A, 163B. In some embodiments, the pressure sensors are solid state silicon diaphragm infusion pump force/pressure transducers.
In an implementation, the line connector tool 200 may include a first line holder 210, e.g. the bag line holder for holding a line connector from the dialysate bag, a second line holder 220, e.g., a disposable line holder for holding a line connector from a disposable set of the PD machine 102 to be connected to the dialysate bag, and a drive mechanism 230 for driving connection of the tubes in the holders. As illustrated, the drive mechanism 230 may be implemented as mechanical actuation mechanism, such as a rotating crank mechanism using, for example, a threaded screw rod configuration and rotational crank. In other implementations involving mechanical actuation, which are illustrated as alternatives in the figure in the dashed-line box, other types of drive mechanisms may include a ratchet mechanism 231 and/or a squeeze action mechanism 232 having a grip handle that drives gearing inside the body of the mechanism 230, and which may also include spring-loading components for reversal. The line connector tool 200 may include a base 205 that remains stationary when the line connector tool 200 is in use, which in various implementations may be achieved by sufficient weight to not move significantly or by clamping or adhering (e.g. suction cups, hook-and-loop fasteners, etc.) to a surface.
The connector 251a that is on the tubing 251b from the bag 250 is held in place in the first (bag) line holder 210 and cannot rotate or move. It can be placed using only one hand. The connector 252a on the disposable set tubing 252b from the cycler disposable set may be positioned on the second (disposable set) line holder 220. The positioning of the connectors 251a, 252a on the line connector tool 200 may enable the user to remove the connector caps from each of the lines, but uncapped surfaces of the connectors subject to aseptic technique should not touch the line connector tool 200. After placement of the connectors 251a, 252a, the drive mechanism 230 is engaged. For example, the drive mechanism 230 may be engaged by circular motion (e.g. arrow 261) of the rotating crank mechanism to cause rectilinear motion (e.g. arrow 262) of the line holder 220 towards the bag line holder 210 to a point where the connectors 251a, 252a make contact. As discussed herein, other implementations of the drive mechanism 230 and concomitant motion techniques are possible and contemplated.
The disposable line holder 220 has the ability to rotate but only after engagement with the connector in the bag line holder 210. That is, after the two connectors 251, 252a make full contact, the drive mechanism 230 provides for the disposable line holder 220 to rotate (e.g. arrow 263) the connector 252a clockwise until a “thumb tight” connection is established. In an embodiment, the thumb tight connection may be established by a torque controller 240, e.g. torque limited gearing of the drive mechanism 230 and/or other appropriate torque limiter or disconnect mechanisms, e.g. gearsets, friction plates, magnetic mechanisms etc., at which point the rotational movement of the disposable set line holder 220 is ended. The disposable set line holder 220 may then be disengaged from the connector 252a, leaving the user free to pull the now connected lines from the bag line holder 210. This connection process may be reversible, in that a user may have the disposable set line holder 220 fully extended, then put the connectors into place in each holder and be able to disconnect the lines by moving the disposable set line holder 220 in reverse, causing it to counter rotate to unscrew the connection to the bag 250.
Implementations discussed herein may be combined with each other in appropriate combinations in connection with the system described herein. Additionally, in some instances, the order of steps in the flow diagrams, flowcharts and/or described flow processing may be modified, where appropriate. The system may further include a display and/or other computer components for providing a suitable interface with a user and/or with other computers. Aspects of the system described herein may be implemented or controlled using software, hardware, a combination of software and hardware and/or other computer-implemented or computer-controlled modules or devices having described features and performing described functions. Data exchange and/or signal transmissions to, from and between components of the system may be performed using wired or wireless communication. This communication may include use of one or more transmitter or receiver components that securely exchange information via a network, such as the Internet, and may include use of components of local area networks (LANs) or other smaller scale networks, such as Wi-Fi, Bluetooth or other short range transmission protocols, and/or components of wide area networks (WANs) or other larger scale networks, such as mobile telecommunication networks.
Software implementations of aspects of the system described herein may include executable code that is stored in a computer-readable medium and executed by one or more processors. The computer-readable medium may include volatile memory and/or non-volatile memory, and may include, for example, a computer hard drive, ROM, RAM, flash memory, portable computer storage media, an SD card, a flash drive or other drive with, for example, a universal serial bus (USB) interface, and/or any other appropriate tangible or non-transitory computer-readable medium or computer memory on which executable code may be stored and executed by a processor. The system described herein may be used in connection with any appropriate operating system. The meanings of any method steps of the invention(s) described herein are intended to include any suitable method of causing one or more parties or entities to perform the steps unless a different meaning is expressly provided or otherwise clear from the context.
As used herein, an element or operation recited in the singular and preceded with the word “a” or “an” should be understood as not excluding plural elements or operations, unless such exclusion is explicitly recited. References to “one” embodiment or implementation of the present disclosure are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features. Furthermore, a description or recitation in the general form of “at least one of [a], [b] or [c],” or equivalent thereof, should be generally construed to include [a] alone, [b] alone, [c] alone, or any combination of [a], [b] and [c].
Implementations of the invention will be apparent to those skilled in the art from a consideration of the specification or practice of the invention disclosed herein. It is intended that the specification and examples be considered as exemplary only, with the true scope and spirit of the invention being indicated by the following claims.
