Process and system for fluid management during reinjection of adipose tissue

Abstract

The invention is a process and system, consisting of a reinjection pump, connecting tubing, a reinjection cannula and a recipient site, with fluid management features including a peristaltic pump head and controls for pressure limits, flow rates and flow distribution wherein the process of controlling the reinjected fat and fluid is unique because of the control of flow rates, pressures, matching cannula hole sizes, and maintaining a closed continuous system where the harvesting and reinjection is done all together with a completely closed system. The process utilizes a method and control system to manage pressure levels during reinjection procedures of viable soft tissue. Although this case specifically relates to its use in the reinjection of adipose fat and other tissue back into the body during liposuction procedures, it can be applied to any medical procedure of introducing or re-introducing materials into the body.

Claims

1. A process and system of parts that make up a system to transfer adipose tissue with fluid management features, comprising the following: a. a container for the harvested adipose tissue, with an adequate port for removing the adipose tissue using the reinjection pump and flexible tubing b. a reinjection pump, which uses a peristaltic pump head to pump adipose tissue and a touch screen interface for controls c. flexible tubing creating fluid communication between a container, and the reinjection cannula. d. a reinjection cannula, comprised of a long, hollow metal tube with one or more openings at or near the distal end, fitted onto a hand piece, and with a tapered transition point where the flexible tubing attaches to the cannula. e. a recipient site, which is anywhere the adipose tissue goes when it leaves the reinjection cannula. f. a sensor for providing feedback of internal pressure in the flexible tubing to the reinjection pump, wherein the sensor is attached to a housing that clamps around the flexible tubing, such that the sensor is held firmly against the outside of the flexible tubing, and such that the sensor is a load cell. g. a live readout of the internal pressure is displayed on the touch screen interface h. wherein the sensor housing has a quick release locking mechanism to allow easy, quick access for installing/uninstalling the flexible tubing. i. where one or more component(s) of the housing of the sensor of claim 1e is/are permanently attached to the reinjection pump enclosure. j. where the reinjection pump allows for control of motor speed, typically in revolutions per minute. k. where the reinjection pump allows for control of flow rates. l. the internal pressure may be set as an upper limit by the user on the reinjection pump. m. the flow distribution pattern is set by the user using controls on the reinjection pump.

2. The process and system of parts of claim 1 wherein one or more component(s) of the housing of the sensor of claim 1e is/are free floating, while still allowing the firm contact of the sensor to the flexible tubing.

3. A process and system of parts that make up a system to transfer adipose tissue with fluid management features, comprising the following: a. a container for the harvested adipose tissue, with an adequate port for removing the adipose tissue using the reinjection pump and flexible tubing b. a reinjection pump, which uses a peristaltic pump head. c. flexible tubing creating fluid communication between a container, and the reinjection cannula. d. a reinjection cannula, comprised of a long, hollow metal tube with one or more openings at or near the distal end, and fitted onto a hand piece, and with a tapered transition point where the flexible tubing attaches to the cannula. e. a recipient site, which is anywhere the adipose tissue goes when it leaves the reinjection cannula. f. a sensor for providing feedback of internal pressure in the flexible tubing to the reinjection pump, such that the sensor is a transducer of any of the following types: piezoresistive strain gauge, capacitive, electromagnetic, piezoelectric, optical, potentiometric, resonant, thermal, or ionization. g. a live readout of the internal pressure is displayed on the touch screen interface h. where the reinjection pump allows for control of motor speed, typically in revolutions per minute. i. where the reinjection pump allows for control of flow rates. j. the internal pressure may be set as an upper limit by the user on the reinjection pump. k. the flow distribution pattern is set by the user using controls on the reinjection pump.

4. A process and system of parts that make up a system to transfer adipose tissue with fluid management features, comprising the following: a. a container for the harvested adipose tissue, with an adequate port for removing the adipose tissue using the reinjection pump and flexible tubing b. a reinjection pump, which uses a peristaltic pump head. c. flexible tubing creating fluid communication between a container, and the reinjection cannula. d. a reinjection cannula, comprised of a long, hollow metal tube with one or more openings at or near the distal end, and fitted onto a hand piece, and with a tapered transition point where the flexible tubing attaches to the cannula. e. a recipient site, which is anywhere the adipose tissue goes when it leaves the reinjection cannula. f. a sensor for providing feedback of internal pressure in the flexible tubing to the reinjection pump, wherein the motor is monitored for changes in loading based on changing pressures in the flexible tubing, such that the increased load of the motor is monitored using a sensor for current, voltage, torque, force or any combination of two or more of these. g. a live readout of the internal pressure is displayed on the touch screen interface h. where the reinjection pump allows for control of motor speed, typically in revolutions per minute. i. where the reinjection pump allows for control of flow rates. j. the internal pressure may be set as an upper limit by the user on the reinjection pump. k. the flow distribution pattern is set by the user using controls on the reinjection pump.

5. The flow distribution of any of the preceding claims wherein the frequency of the stop and go motion and the speed of rotation of the motor are set by the user through the reinjection pump.

6. The recipient site of any of the preceding claims wherein the recipient site is a location(s) in the patient undergoing the reinjection procedure.

7. The process and system of parts of any of the preceding claims wherein the flexible tubing is made from one continuous piece.

8. The tubing of claim 7 wherein the peristaltic pump is able to pump on any section of the tubing.

9. The tubing of claim 7 wherein the external transducer for measuring internal pressure can be sensed on any section of the tubing.

10. The process and system of parts of any of the preceding claims wherein the flexible tubing is made from one or more sections of tubing.

11. The tubing of claim 10 wherein each section may vary in material, diameter and size.

12. The tubing of claim 10 wherein the peristaltic pump head is required to pump on a specific section of the tubing.

13. The tubing of claim 10 wherein the external transducer for measuring internal pressure is required to be sensed on a specific section of the tubing.

14. The pressure limit of any of the preceding claims wherein the monitoring of internal pressure extends to the recipient site, since any given internal pressure of the flexible tubing is also the pressure of the fluid just exiting the cannula into the recipient site.

15. The pressure monitoring of claim 14 wherein the surgeon may control, observe and gain insight into the pressure at the recipient site through the live readout of pressure displayed by the reinjection pump, including interstitial pressure of the recipient site, tissue type of the recipient site, overfilling of adipose tissue due to holding the reinjection cannula in one place too long, patient discomfort from pressure limit too high.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0041] FIG. 1: A basic overview of the entire reinjection system

[0042] FIG. 2: A perspective overview of the reinjection pump

[0043] FIG. 3: A front view of the peristaltic pump head action with tubing installed

[0044] FIG. 4a: A side view representation of the open external sensor with tubing

[0045] FIG. 4b: A side view representation of the closed external sensor with tubing

[0046] FIG. 5: A graphical representation of the flow pattern feature.

[0047] FIG. 6: A pictorial diagram and cross-sectional of a typical cannula

DETAILED DESCRIPTION OF THE INVENTION

[0048] The present invention consists of a process and system of parts that together form a reinjection system and process for transferring adipose tissue and providing fluid management. The process and system of parts consists of a canister or container (1), reinjection pump (3), flexible tubing (2), a reinjection cannula (4) and a recipient site (5). It includes the specific novel features of this process not previously utilized in the prior art. FIG. 1 shows an overview of the setup of the apparatus. Adipose tissue that has been harvested is collected in a container (1), which will have a port or entry to allow the adipose tissue to be drawn out. One end of the flexible tubing (2) is attached to the port of the container while the flexible tubing (2) is run through the reinjection pump (3). A reinjection cannula (4) is connected to the other end of the flexible tubing (2), and is used to reinject adipose tissue to the recipient site (5). The container (1) is located on the negative pressure side of the pump (6), in which the negative pressure draws adipose tissue into the flexible tubing (2). The positive pressure side of the pump (7) is located after the reinjection pump (3) and is what pushes the adipose tissue through the flexible tubing (2), the reinjection cannula (4), and ultimately into the recipient site (5). The recipient site (5) includes the patient, however it encompasses anywhere that the adipose tissue goes when it leaves the reinjection cannula (4).

[0049] FIG. 2 shows the perspective view of the reinjection pump (3). It has an enclosure (22), typically made from multiple pieces of formed metal that are fastened together, but it can be made from any kind of molded plastic or polymer. This enclosure (22) holds all the power components that make up the reinjection pump (3), as well as the major components. These include the peristaltic pump head (9), the external mounted to a DC motor that can rotate in both clockwise and counter clockwise directions. The external pressure sensor (10) is made of several components, of which the base (14) may be permanently mounted to the enclosure (22), or it may be free floating. Either way, the purpose is to monitor the internal pressure (21) in the tubing and provide feedback to the reinjection pump (3). The sensor for measuring pressure may even be a free standing device that is separate to the reinjection pump (3), however this is still under the patented idea as long as the freestanding device provides feedback of internal pressure (21) to the reinjection pump (3) in the form of an electrical signal. The touch screen (8) allows the user to set variables and settings of the reinjection pump (3). These settings include, but are not limited to the revolutions per minute of the motor, the pressure limit, and the number of pulses per minute.

[0050] The setting for revolutions per minute is referred hereafter as the speed of the motor. The speed is also the revolutions per minute of the peristaltic pump head (9), since the motor shaft is directly coupled to the peristaltic pump head (9) shaft. Control of the speed is very important for reinjecting adipose tissue because the tissue can only flow so fast through the flexible tubing (2) and the reinjection cannula (4). The main flow restriction is the small inner lumen of the reinjection cannula (4). If the speed setting is too high, the adipose tissue will be pushed into the flexible tubing (2) faster than it is leaving. This will increase the pressure and may trigger the upper pressure limit of the reinjection pump (3). The reinjection cannula (4) has a machined taper (23) where the flexible tubing (2) connects to the reinjection cannula (4). This taper (23) acts as a down to the smaller inner diameter of the reinjection cannula (4).

[0051] The pressure limit of the reinjection pump is the maximum internal pressure (21) desired inside the flexible tubing (2). If the external pressure sensor (10) detects a pressure that exceeds the limit, it will immediately stop the motor, which begin pumping in reverse until the internal pressure (21) is reduced to near zero. The zero pressure is simply the internal pressure (21) when the sensor is zeroed before the procedure, and is typically atmospheric pressure. The user will have to release and press the footswitch again to resume normal forward pumping. The pressure limit feature using the external pressure sensor (10) automatically limits the pressure, and allows the surgeon to focus on more important matters, such as placement of reinjected tissue.

[0052] The ability to set a number of pulses per minute allows the user to create a pattern to the flow. Pulses are created by rotating the peristaltic pump head (9) forward quickly a small amount, stopping, and moving forward again quickly a small amount. When set correctly, the pulses propagate through the fluid in the flexible tubing (2), with the effect that the fluid exits the end of the reinjection cannula (4) in small boluses, or droplets, automatically. This can eliminate the back and forth motion of the hand during reinjection by automatically placing a segmented array of boluses with a straight movement of the cannula end. Controlling the bolus size is an important factor in maintaining adipose tissue viability by spacing out the agglomerates and maximizing vascularization.

[0053] FIG. 3 shows a side view of the peristaltic pump head (9) with the flexible tubing (2) installed. The peristaltic pump uses positive displacement to move material, and this is created using multiple rollers (11). As the DC motor turns the rollers (11), a roller pushes the tubing against the surface of the pump head creating a seal by compression (12). As the roller moves past the compressed area, the flexible tubing (2) goes back to its original shape. This creates the negative pressure side of the pump (6) and draws in more fluid. The fluid trapped before the compression (12) point is forced forward and creates a positive pressure side of the pump (7). Before the first roller releases the compression (12) section, the roller behind it initiates a new compression (12) section and the process repeats. Thus the rollers (11) act as both the pumping mechanism, and a valve to separate the positive and negative pressure sides.

[0054] FIG. 4a shows a side view of the preferred embodiment of the external pressure sensor (10). When the locking mechanism (19) is released, the top hinge (18) opens to allow the tubing to be installed. Both the base (14) and the top hinge (18) have a tubing channel (17) that matches the outer diameter of the flexible tubing (2). The transducer/load cell (13) is rigidly attached (15) to the base (14) with the sensing component (16) of the transducer/load cell (13) protruding into the tubing channel (17). The flexible tubing (2) is placed into the tubing channel (17), the top hinge (18) is closed, and the locking mechanism (19) is engaged. The locking mechanism (19) simply prevents the top hinge (18) from moving and creates a rigid support for the flexible tubing (2) to press against. The spring (20) is used simply to hold open the top hinge (18) when the locking mechanism (19) is not engaged. The spring (20) also provides a force to keep the locking mechanism (19) engaged when the external pressure sensor (10) is closed with no flexible tubing (2).

[0055] FIG. 4b shows the same side view as FIG. 4a, but with the external pressure sensor (10) in the closed position with flexible tubing (2) installed. This figure shows a representation of the deformation of the flexible tubing (2) when it is pressed against the sensing component (16). With the transducer/load cell (13) rigidly attached (15) to the base (14), the only part that can move is the sensing component (16) as it deforms the internal structure of the transducer/load cell (13) containing the strain gauge. The flexible tubing (2) is confined by the tubing channel (17) and will not expand in any direction except towards the sensing component (16). This ensures that the expansion of the flexible tubing (2) from the force caused by the internal pressure (21) is focused towards the sensing component (16). This force, which is defined as a force over a specific area, varies directly with the internal pressure (21) in the tubing, and thus an accurate relationship is made between the electrical signal from the transducer/load cell (13) and the internal pressure (21). A major benefit to this sensor is that it is external, and does not need any direct contact with the adipose tissue inside. This makes maintaining sterility very easy, and the entire external pressure sensor (10) is reusable. Reusability increases the accuracy and ease of use by eliminating repeated calibration steps.

[0056] FIG. 5 shows a representation of the flow distribution pattern and how it is controlled using the pulse feature. The pulses can be set using two variables, the rate of the stop and go motion, and the speed of the motor during each go motion. The purpose of the pulse function is to create separate, segmented boluses of adipose tissue that exit the reinjection cannula (4). The rate of the stop and go motion can be described as the number of pulses per minute, and can be attributed to the number of droplets per minute. The amount of rotation during each pulse affects the size of each droplet. A higher speed means the motor rotates farther during each pulse, and pushes a larger volume of fluid each time. This type of flow distribution is important to maximize vascularization to the adipose tissue. Distributing the agglomerates of adipose tissue by spacing them out gives each agglomerate the largest chance of finding a blood supply.

[0057] The present invention includes a focus on maintaining a constant, smooth, continuous lumen throughout the entire system. This means that after the adipose tissue leaves the container (1), the inner diameter of the flexible tubing (2) and all connections are to be maintained through all processes, until it reaches the reinjection cannula (4). This helps the adipose tissue move gently along the flexible tubing (2) path by removing choke points and small orifices to squeeze through, such as luer lock fittings and one way valves. The system contains only one component that has an active role in contacting the adipose tissue, the flexible tubing (2). This flexible tubing (2) comes in disposable, pre-sterilized packs to allow a sterile environment for the adipose tissue.