MEDICAL DEVICE FOR MINIMALLY INVASIVE THERAPY WITH AT LEAST TWO SEPARATE SUCTION LINES

Description

Subject of the invention

[0001] A medical device for use in minimally invasive surgery with at least two different, independently controllable suction lines. The suction lines preferably have different suction characteristics. State of the art

[0002] In minimally invasive surgery, a cavity (natural or artificially created body cavity) is often dilated by introducing a fluid which puts pressure on the cavity and thus enables the dilation. Therapeutic treatment, for example the smoothing of cartilage, is carried out using inserted medical instruments (see below). An example of such a device is shown in EP 1382291 A2. For this purpose, this fluid is suctioned out by the respective medical instrument as intended in order to ensure its function and to minimize side effects on the dilated cavity. Examples of such medical instruments are instruments with moving blades where the suction draws in the tissue to be severed and removes the tissue remnants from the cavity (shaver, morcellator) and then transports them away outside the cavity.Another example of such medical instruments are ablation devices operated with high-frequency current (HF instruments), in which the by-products of the application such as water vapor or smoke gases are sucked away. In addition, the resulting heat can be dissipated from the cavity by sucking the fluid out through the instrument body. In order to maintain the pressure and thus the expansion of the cavity, the supply of fluid to the cavity is increased accordingly by an adapted control system, i.e. by at least the additional volume sucked out. Tracking the sucked-out fluid is difficult because the quantities sucked out via the medical instruments and the times of suction can be influenced by the surgeon opening valves on the handpiece.coupled via valves on the medical device and not known to the medical device for providing fluid management via sensors. Typically, medical devices for providing fluid management only have a pressure sensor on the supply side, which can determine the pressure in the cavity via the fluid communication along the supply line ending in the cavity and base a control on this.

[0003] The disadvantage is that the fluid, which leads to a reduction in expansion through the suction on the medical instruments, can only be replenished on the basis of an indirectly connected pressure sensor. To solve this problem, the prior art approach involves detecting activation of the medical instrument connected to the suction and triggering a corresponding resupply or increase in delivery. Detection is via the power requirement (e.g. EP 2 165 720) by connecting the medical instrument directly to a supply socket of the medical device for providing fluid management. Other options for detecting the operation of the medical instrument are known. A disadvantage of this solution is the high effort required to detect the operating state without obtaining information about the extent of the leak.Therefore, in order to prevent the cavity from collapsing in the event of a sudden increase in outflow (e.g. due to the use of a shaver), the suction control must still rely on additional sensors or devices for this compensation, since although the time of the outflow is known in this way, the amount of leakage depends on the flow resistance of the medical instruments used, which are usually replaced and are not permanently connected to the control unit of the medical instruments.

[0004] Another challenge is ensuring the right amount of fluid flowing through the cavity while maintaining the most stable pressure possible. This flow rate is necessary to remove ablated tissue and ensure visibility in the cavity.

[0005] The flow rate can be kept constant and preselected by the surgeon, or it can be provided individually or additionally upon request by the surgeon at a temporarily or permanently increased rate (flush / wash). If leaks occur through openings in the expanded cavity, fluid escapes and the pressure drops. While flow is ensured due to the amount of fluid introduced, pressure may not be maintained due to an excessive outflow.

[0006] Another approach is to keep the pressure constant. This results in a very high flow rate in the event of a leak, as the outflow resistance may become very low or the cross-sectional area for drainage may become very large as soon as the situation changes, such as additional incisions and instrument removal.

[0007] Another situation where such suction is used requires balancing the amount of fluid introduced and removed. This serves to estimate the exposure of the patient, whose cavity is dilated, to the absorbed fluid. For this purpose, the portions flowing out of the patient are collected via pads connected to a vacuum vessel and funnel, and the fluid from the floor below the treatment site is collected into a vacuum vessel using a floor suction device. This vacuum vessel is connected to a suction unit that creates the vacuum necessary for transport to the vacuum vessel.If one of the supply lines is not filled with fluid—where the fluid in this specific case is a liquid—but is open to the atmosphere, the negative pressure collapses very quickly, and other vessels also connected to this negative pressure source cannot transport the fluid, as the negative pressure is preferentially equalized via the path of least resistance, which here is created between the negative pressure vessel and the atmosphere by the transport of air. In such a situation of negative pressure equalizing in the negative pressure branch, a connected medical instrument is therefore not controlled via the suction line to the negative pressure vessel and supplied with the required amount of fluid, but only via the fluid driven through by the pressure of the expansion.If the medical device uses moving blades where the suction draws the tissue to be severed (shaver, morcellator), its function is impaired. One solution is to disconnect the suction line from the atmosphere or to close a valve built into it, thus preventing negative pressure compensation. However, this distorts the balance due to the temporary accumulation of the fluid not suctioned, at least until the connection is reestablished. Overall, this places a significant burden on the surgeon.

[0008] Furthermore, the fluid pump used for suction is equipped with specific characteristics based on its technical design. Using a peristaltic pump, the flow characteristics (pressure and flow rate) are more easily controllable, and blockages in the suction lines due to tissue debris can be detected more effectively and quickly. The pumping device itself is smaller and produces less noise than a Venturi or diaphragm pump. The peristaltic pump can be considered a flow sink and is advantageous when a precise and very defined flow is required.

[0009] Advantages of the Venturi or diaphragm pump include a pressure surge-free, uniform flow and a very fast rise time. In the context of the invention, the Venturi or diaphragm pump is typically used in minimally invasive surgery to generate a vacuum by conveying gaseous fluid. It requires a rigid vacuum container for suction, in which the suctioned fluid is collected. Other applications are conceivable, but in these cases the pump comes into contact with the suctioned fluid and must be designed as a disposable product or cleaned. The Venturi or diaphragm pump can be considered a pressure sink and is advantageous in conditions of high flow resistance. This type of pump is referred to as a vacuum-generating pump device.

[0010] The peristaltic pump can pump the extracted fluid directly through the inserted tubing into an open container. However, due to its operating principle of squeezing a section of tubing by rolling, it also acts as a barrier against an applied vacuum. Thus, the peristaltic pump can also be connected with its discharge side to the suction side of another pump (e.g., a vacuum container).

[0011] A concept with two different pumping devices is known from WO93 / 17729. WO93 / 17729 discloses a solution comprising a coupled large and small vacuum container, each with a different pumping device connected to it, for use as a suction and irrigation instrument in intraocular therapy. These pumping devices are used alternatively and are connected via the vacuum container to a suction and irrigation instrument with only one suction line. The use of only one instrument, as described in WO93 / 17729 with different suction pump characteristics, is the essential difference from the situation underlying this invention. The situation underlying this invention places different demands on the suction lines, as these are each connected to different medical instruments.WO93 / 17729 describes a suction and irrigation instrument whose properties are known and which is permanently connected to the hose cassette. In the situation underlying this invention, multiple configurations for the use of individual suction lines are advantageous, and the properties of the connected medical instruments are not previously known to the medical device for providing fluid management.

[0012] A prior art device is disclosed in WO2017 / 095679A1. Inventive solution

[0013] The solution according to the invention for a medical device for providing fluid management for flushing a cavity consists in a device with at least one pump device for supplying fluid and two suction devices which can be controlled separately from one another, as defined in claim 1.

[0014] The invention therefore relates to a medical device for flushing cavities in minimally invasive surgery, comprising (i) storage container (1) for the rinsing liquid, (ii) supply line (2) for supplying rinsing liquid into the body cavity (11), (iii) controlled pump (3) for supplying liquid (iv) controlled first vacuum pump (4) (v) controlled second vacuum pump (5) (vi) first medical instrument (6) with a first suction line (7) (vii) second medical instrument (8) with a second suction line (9) (viii) waste container (10), connected to the first suction line (7) and to the second suction line (9).

[0015] In a particular embodiment of the invention, the waste container (10) is connected to the first suction line (7), to the second suction line (9) and to the controlled second vacuum pump (5) through the line (12).

[0016] Further embodiments of the invention are described below.

[0017] A preferred pumping device for fluid supply consists of a roller pump, as described in countless variants in the prior art. The device according to the invention uses a pump capable of delivering a fluid flow of 2.5 l / min and generating a pressure of 300 mmHg. Alternatively, another positive displacement pump, such as a diaphragm pump or an impeller pump, can be used for fluid supply, provided they can generate the same fluid flow and pressure.

[0018] Roller pumps, Venturi pumps, or diaphragm pumps can be used for the suction device. All types of piston compressors, screw compressors, and turbo compressors are also suitable for the invention. Roller pumps were already described above in the prior art. In diaphragm pumps, a separating diaphragm is mechanically moved to cyclically enlarge and reduce the size of a chamber. Two valves arranged at the inlet and outlet of the chamber ensure that the fluid flow can only be unidirectional. For the purpose of the invention, the diaphragm is driven by a brushless DC electric motor. In Venturi pumps (also called jet pumps), a motive jet is used to generate the pumping action. The motive jet can consist of liquid (preferably water) or gas (e.g., air or nitrogen). For the purpose of the invention, air is preferably used as the motive jet.

[0019] In any case, the pump used in the suction device must be capable of generating a vacuum of 450 mmHg and a fluid flow of 1.5 l / min. Roller impeller and diaphragm pumps have the advantage of being very precisely controllable. In comparison, Venturi pumps are less precisely controllable.

[0020] Improvements in controllability can be achieved through valve control.

[0021] The device according to the invention has two different types of pumps for the suction, e.g. a roller wheel pump and a Venturi pump or a roller wheel pump and a diaphragm pump or a Venturi pump and a diaphragm pump.

[0022] Particularly preferably, the device according to the invention for the suction comprises a roller wheel pump and a Venturi pump or a roller wheel pump and a diaphragm pump.

[0023] A particular embodiment of the invention has at least two roller wheels that pressurize a tube in the manner of a peristaltic pump, and at least one pumping device for generating a vacuum according to the Venturi principle or as a diaphragm pump. One roller wheel (inflow) is used to pressurize the cavity to be expanded with a fluid. The inflow roller wheel has a sensor for the rotational speed. A pressure sensor is coupled to the tubing set via a membrane or a similar solution. The pressure sensor indirectly detects the cavity pressure. The rotational speed indirectly detects the flow rate. A second roller wheel (outflow) can also have a sensor for the rotational speed and is used to suction the fluid out of the cavity using at least one tube.

[0024] A vacuum pumping device, either based on the Venturi principle or as a diaphragm pump, is used to suction fluid from the tube via a vacuum reservoir. This can occur simultaneously or independently of the suction through the outflow roller wheel.

[0025] With a device according to the invention, in the simplest case, the constant fluid flow required for rinsing (flow rate) can be met via one suction line, and an increased fluid flow required for additional rinsing can be met via at least one further suction line. In the simplest case, no valves are necessary for this, as the peristaltic pump is leak-tight and the vacuum-generating pumping device can be reduced to such an extent that nothing is sucked out. The advantage over a pure double-roller pump arises from the simple generation of a high pre-pressure for suction through a high flow resistance and the avoidance of slippage on the roller wheel at high speeds, which would cause the flow rates to fluctuate uncontrollably. The high speeds become necessary when a high pre-pressure must be generated for suction. In this case, pre-pressure refers to the vacuum at the pumping device, which is achieved by suction with the vacuum pump.Due to the pressure gradient between the joint cavity and the vacuum container, a flow rate results that depends on the flow resistance of the instrument used.

[0026] The basic function of flow at stable pressure in the cavity can be achieved in one embodiment by combining an inflow roller wheel with suction via the vacuum pump. Here, the specified pressure in the cavity is regulated according to the state of the art as the input for the control. As input for the control, a sensor detects the fluid pressure via a diaphragm in fluid contact with the cavity. This sensor is positioned in the fluid path behind the inflow roller wheel. A constant flow is generated by coupling this inflow roller wheel with the volume discharged by the generated negative pressure. If inflow and outflow are equal, a flow at a stable cavity pressure results. Further actions are required by the operator, such as requesting a higher flow or opening additional suction lines.For example, the outflow roller wheel can be used to generate a corresponding (additional) negative pressure in another suction line that is also connected to the vacuum vessel. This negative pressure generated by the outflow roller wheel is directly compensated for by the inflow roller wheel, for example, by increasing the speed of the inflow roller wheel by the speed of the outflow roller wheel. Other solutions that better approximate the delivered volume flow are also conceivable. The volume delivered per unit of time (volume flow) can change depending on the hose diameter and thickness of the hose wall, as well as the material used. The direct volume increase on the inflow side in response to the activation of the outflow roller wheel effectively prevents a pressure drop caused by a larger withdrawal of fluid from the cavity.

[0027] Other embodiments with at least 2 suction lines as individually controllable peristaltic pumps, or with at least 2 suction lines with separately controllable diaphragm or Venturi pumps or other combinations are also according to the invention. Examples of implementation

[0028] The present invention is further illustrated by the following examples, without being intended to be limiting. Those skilled in the art can develop further embodiments of the invention based on the present descriptions and their experience in the field without having to resort to inventiveness.

[0029] One possible configuration of the pumping devices and the cavity can be such that the inflow pump is connected to the endoscope via a supply line for viewing the cavity, and both an HF instrument and a medical instrument with moving blades (e.g., a shaver) are connected to the outflow roller wheel on the negative pressure side. The latter can be controlled via a clamping device or a valve for the individual tube. The negative pressure-generating pump device is connected directly to the cavity via the negative pressure container (third suction line, see end of paragraph). The outflow roller wheel is also connected to the negative pressure container on the positive pressure side. This container serves as a collection container and can be designed so that it does not need to be changed or emptied during a typical procedure.The suction branch on the roller wheel is closed during operation and when not in operation, so that the negative pressure is not affected by the operating state of the roller wheel. The two suction lines on the outflow roller wheel can be individually occluded using clamping devices, so that the states... 1-0 (vacuum pump open - outflow roller wheel stopped), 0-1 (vacuum pump closed - outflow roller wheel in motion), 1-1 (vacuum pump open - outflow roller wheel in motion) via clamping device and the state 0-0 (vacuum pump closed - outflow roller wheel stopped), can be generated by the roller wheel being at a standstill.

[0030] The condition of the third suction line can be controlled by controlling the vacuum pump.

[0031] It is advantageous to position the clamping device between the outflow roller wheel and the medical instrument and to control it via a trigger device accessible to the surgeon. This solution allows the device to detect the status of the clamping device and incorporate it into the pressure and flow control for fluid management.

[0032] Example 1:In the embodiment outlined above, in-outflow management can be achieved when using medical instruments (e.g. shaver or HF), without being dependent on recording the operating states of the medical instruments. The outflow roller wheel pump provided in the device concept for providing fluid management and the vacuum-generating pump device can be controlled separately to provide the required vacuums and flow rates for the suction lines, i.e. the fluid connections from the cavity to the device. Both pump devices are adjustable, with the outflow roller wheel being able to, for example, provide greater suction from the medical instrument (e.g. shaver / HF), and the vacuum-generating pump device ensuring a continuous flow. A major advantage for the surgeon is that there is no longer any need to unplug or change the hoses.Closing the tap on the trocar, the sleeve typically used for inserting the endoscope.

[0033] In this example, rapid pressure changes are avoided in the arthroscopy scenario. This is because, with prior art solutions, the pressure drop at the sensor on the inflow roller wheel when opening the suction lines to a medical instrument (e.g., shaver / HF) creates a high demand for additional fluid delivery. This pressure drop can only be counteracted relatively late. This pressure peaks result in greater extravasation of the fluid than with the inventive solution. This extravasation leads to adverse swelling in the area surrounding the expanded cavity. This embodiment of the inventive solution enables, for the first time, "low-pressure arthroscopy" with a cavity pressure of slightly over 30 mmHg in the joint. This is because, with prior art devices, the pressure fluctuations are too great, causing the cavity to collapse.

[0034] Example 2: In the embodiment outlined above, a medical instrument with a high flow rate requirement (e.g., a shaver, morcellator, or other devices that cut and / or suction tissue pieces) can be connected directly to the outlow roller wheel, which pumps into the vacuum reservoir. A medical instrument with high flow resistance (e.g., an HF instrument) can be connected to the vacuum-generating pump device and, via the same suction line, to the cavity. The medical instrument with high flow resistance is clamped off via a valve, and the suction line is only opened upon activation.

[0035] The advantage is rapid suction on the medical instrument with high flow resistance, very stable cavity pressure, and a flow rate that can be adjusted independently of the cavity pressure. This example also offers the surgeon the advantage of eliminating the need to unplug or close the stopcock on the trocar.

[0036] Example 3:In the embodiment outlined above, the outflow roller wheel can be connected directly to the cavity, and the vacuum-generating pump device can be connected to a medical instrument with moving blades (e.g., a shaver, morcellator, or other devices that separate and / or aspirate tissue pieces). This allows the cavity pressure to be well controlled, and the inflow and outflow can be well regulated. When the medical instrument with moving blades is activated, the pumping principle prevents pressure fluctuations, thus ensuring a stable cavity wall. This is particularly helpful in cavities with very flexible walls, such as the uterus.

[0037] Example 4:In the embodiment outlined above, the outflow roller wheel and the inflow roller wheel can be connected directly to an endoscope with separate channels for inflow and outflow, which is located in the cavity to create a continuous flow. The vacuum-generating pump unit can be connected to a suction instrument or, via a valve, additionally to the endoscope. In urology, during stone removal in the area of ​​the ureter or renal calyx, the stone is fixed with an instrument that grasps the stone (stone catcher basket). The grasping process can be promoted by activating the suction line with the vacuum-generating pump unit, whereby the additional suction positions the stone in the instrument.This pulsed increase in suction is very advantageous because it does not change the situation in the cavity, creating only additional suction toward the suction opening, the effect of which can be compensated for by increased inflow. Due to the length and diameter of the tube (i.e., flow resistance), an enormous pre-pressure is required, which is best achieved using the vacuum-generating pumping principle. During normal operation, precise pressure control over the smallest volumes is required (risk of damage to the renal calyx region), which is best achieved with peristaltic pumps. However, these cannot generate the necessary pre-pressure quickly enough for a suction pulse, or would be far oversized if they did. List of reference symbols

[0038] (1) Storage container for the rinsing liquid, (2) Supply line for supplying rinsing liquid into the body cavity (11) (3) Controlled pump for supplying liquid (4) Controlled first vacuum pump (5) Controlled second vacuum pump (6) First medical instrument (7) First suction line on the first medical instrument (8) Second medical instrument (9) Second suction line on the second medical instrument (10) Waste container (11) Body cavity (12) Line from waste container to the controlled second vacuum pump.

Claims

1. A medical device for rinsing cavities during minimally invasive surgery, comprising: (i) a reservoir (1) for the rinsing liquid, (ii) a feed line (2) for feeding rinsing liquid into the body cavity (11), (iii) a controlled pump (3) for feeding liquid, (iv) a controlled first vacuum pump (4), (v) a controlled second vacuum pump (5), (vi) a first medical instrument (6) with a first suction line (7), (vii) a second medical instrument (8) with a second suction line (9), (viii) a waste container (10) connected to the first suction line (7) and the second suction line (9), characterized in that the controlled first vacuum pump (4) and the controlled second vacuum pump (5) are different.

2. The medical device according to Claim 1, characterized in that the waste container (10) is connected to the first suction line (7), the second suction line (9), and the controlled second vacuum pump (5) through a line (12).

3. The medical device according to Claim 1 or 2, characterized in that the controlled pump (3) for feeding liquid is a roller wheel pump.

4. The medical device according to Claim 1, 2, or 3, characterized in that the controlled first vacuum pump (4) and / or the controlled second vacuum pump (5) is a roller wheel pump.

5. The medical device according to at least one of the Claims 1 to 4, characterized in that the controlled first vacuum pump (4) is a roller wheel pump and the controlled second vacuum pump (5) is a Venturi pump.

6. The medical device according to at least one of the Claims 1 to 4, characterized in that the controlled first vacuum pump (4) is a roller wheel pump and the controlled second vacuum pump (5) is a diaphragm pump.