Heating / cooling unit for an oxygenator

Abstract

A system for extracorporeal blood circulation, with an oxygenator (10) comprising a heat exchanger (11) designed to heat or cool blood from a patient's extracorporeal blood circulation; a reservoir (20) designed to store a heat exchange medium and connected to the heat exchanger (11); and a thermoelectric heating / cooling device (14); wherein the thermoelectric heating / cooling device (14) is connected to the reservoir (20) by means of a further heat exchanger (23) and is designed to heat or cool the heat exchange medium in the reservoir (20) by means of the further heat exchanger (23).

Description

Field of invention

[0001] The present invention relates to a device by means of which an oxygenator, for example an oxygenator of a heart-lung machine, can heat or cool blood from an extracorporeal blood circulation of a patient. Background of the invention

[0002] Oxygenators are devices used for the extracorporeal enrichment of blood with oxygen. Such oxygenators are used, for example, in heart-lung machines or extracorporeal membrane oxygenation (ECMO) devices. Membrane oxygen generators are commonly used, which can largely prevent embolisms. The transfer of oxygen and carbon dioxide can be reliably controlled using gas mixers and flow meters.

[0003] In addition to oxygenation, the oxygenator also warms or cools the patient's extracorporeal blood. Hypothermia is particularly important for reducing the patient's oxygen consumption. The oxygenator incorporates a heat exchanger to warm or cool the extracorporeal blood. A heat transfer fluid flows through the heat exchanger, transferring heat to the blood (warming) or absorbing heat from the blood (cooling). This fluid is typically supplied to the heat exchanger by a pump and, after heat exchange with the blood, is removed by another pump. The heat transfer fluid, for example, water, is first heated or cooled in a heating / cooling unit (a hypothermia device) before being directed to the heat exchanger.Due to its size and complex structure, the heating / cooling system is designed separately from, for example, the heart-lung machine.

[0004] The heating / cooling system can become internally contaminated with germs if it is not carefully maintained and disinfected. This poses a risk of contaminating equipment and the atmosphere in the operating room, potentially leading to germs entering the patient's bloodstream. Furthermore, state-of-the-art heating / cooling systems are relatively complex and therefore prone to malfunction.

[0005] German patent DE 10 2014 116 601 A1 and US patent 2013 / 0280692 A1 describe a medical device for extracorporeal blood circulation that includes an oxygenator with a heat exchanger. US patent 2014 / 0208654 A1 describes an organ perfusion device with an oxygenator connected to a heat exchanger. US patent 2017 / 0216509 describes a portable medical device for extracorporeal blood circulation that includes an oxygenator with an integrated heat exchanger. German patent DE 20 2011 004 944 U1 teaches a device for the thermal treatment of a patient that includes a heat exchanger on one side of a Peltier element and another heat exchanger on the other side of the Peltier element. DE 10 2004 023598 A1 teaches a hypothermia treatment device with heat exchangers with Peltier elements.DE 10 2016 200 917 A1 teaches a thermal treatment system for treating a patient's neck area, which in particular includes a flow-through temperature control unit with a heat exchanger for cooling water in a circuit, wherein the heat exchanger includes a water tank.

[0006] The present invention is therefore based on the objective of providing a heating / cooling device for an oxygenator that operates reliably, as smoothly and hygienically as possible. Description of the invention

[0007] The aforementioned problem is solved by a system according to claim 1. This system provides an extracorporeal blood circulation system comprising an oxygenator including a heat exchanger configured to heat or cool blood from a patient's extracorporeal circulation, a reservoir configured to store a heat exchange medium and connected to the heat exchanger, and a thermoelectric heating / cooling device. The thermoelectric heating / cooling device is connected to the reservoir via a further heat exchanger and is configured to heat or cool the heat exchange medium in the reservoir using the further heat exchanger.

[0008] Here and in the embodiments described below, the system can be or comprise a heart-lung machine, an extracorporeal membrane oxygenation (ECMO) device, or a miniaturized extracorporeal circulation (MECC) device. Here and in the embodiments described below, the thermoelectric heating / cooling device can comprise at least one Peltier element. In particular, a plurality of Peltier elements operating in parallel can be provided. Several Peltier elements can be connected in series.

[0009] The heating / cooling unit, or the Peltier elements, can directly heat or cool the heat exchanger (depending on the selected current direction of the Peltier elements). If the heat exchanger is cooled to a temperature below the blood temperature by the thermoelectric heating / cooling unit (Peltier elements), the blood is cooled; conversely, if the heat exchanger is heated to a temperature above the blood temperature, the blood is warmed. This allows for a completely "dry" system for supplying heat to the oxygenator's heat exchanger, which is virtually maintenance-free and significantly reduces the risk of contamination if not carefully maintained and disinfected (see description above).

[0010] As in conventional prior art systems, a circulation of a heat exchange medium can be provided for cooling or heating the patient's blood; however, the cooling or heating of the heat exchange medium is carried out using the heating / cooling device according to the invention.

[0011] The claimed system comprises a further heat exchanger connected to the said reservoir, wherein the heating / cooling device is connected to the further heat exchanger for the exchange of a quantity of heat.

[0012] Furthermore, the system can include a device for delivering a fluid to the patient's blood, in particular a cardioplegia solution, wherein the heating / cooling device is connected to the fluid delivery device and is configured to heat or cool the fluid, for example, the cardioplegia solution. Thus, in addition to the task of heat exchange with the oxygenator's heat exchanger and therefore heating or cooling the patient's blood, the heating / cooling device can also perform the task of heating or cooling other fluids (such as a cardioplegia solution) used, for example, in a heart-lung machine.

[0013] In all the training systems described above, the heating / cooling unit can comprise a cooling module with multiple Peltier elements and a heating module without Peltier elements. The heating module can, in particular, include a heating coil. Since the efficiency of Peltier elements is limited, they can only be used for cooling. A heat exchanger fluid stored in a reservoir (see above) can be pre-cooled or pre-heated using the cooling module or the heating module, respectively, before the actual operation.

[0014] The following section describes comparative examples that are not part of the invention but are helpful for understanding it, and embodiments of a device according to the invention. The described embodiments are to be regarded in every respect as merely illustrative and not as limiting, and various combinations of the features mentioned are included in the invention. Fig. Figure 1 shows a system according to an example that is not part of the present invention, comprising an oxygenator including a heat exchanger and a thermoelectric heating / cooling device with Peltier elements. Fig. Figure 2 shows a system according to an example that is not part of the present invention, comprising an oxygenator including a heat exchanger and a thermoelectric heating / cooling device with Peltier elements that heats or cools a heat exchange medium stored in a reservoir via a thermal connecting element. Fig. Figure 3 shows a system according to an embodiment of the present invention with an oxygenator comprising a heat exchanger and a thermoelectric heating / cooling device with Peltier elements, which heats or cools a heat exchange medium stored in a reservoir via a heat exchanger.

[0015] In Fig. Figure 1 shows an example of a system not according to the invention. The system shown comprises an oxygenator 10 with a heat exchanger 11. A patient's blood is circulated via the lines 12 and the oxygenator 10 by means of a pump device 13. The blood is enriched with oxygen in the oxygenator 10 and cooled or heated as desired by means of the heat exchanger 11. The oxygen in the Fig. The system shown can be part of a heart-lung machine, an extracorporeal membrane oxygenation (ECMO) device, or a miniaturized extracorporeal circulation (MECC) device, which may include numerous other elements as known in the prior art. The oxygenator 10 can be a membrane oxygenator.

[0016] A thermoelectric heating / cooling device 14 is connected to the heat exchanger 11 via a thermal connection element (contact element) 15. The thermal connection element 15 can comprise a highly thermally conductive metal. Heat transfer between the heat exchanger 11 of the oxygenator 10 and the heating / cooling device 14 occurs directly via the thermal connection element 15, without the need for a liquid heat exchange medium.

[0017] In the Fig. In the example shown, the heating / cooling device 14 features Peltier elements 14a, which allow for essentially maintenance-free operation.

[0018] Another example, which is not part of the present invention, and exemplary embodiments are described in the Fig. 2 or 3 shown. Same elements as in the one in Fig. The example shown in point 1 is labelled with the same reference numerals. The example in the Fig. 2 and Fig. The system shown in Figure 3 comprises an oxygenator 10 with a heat exchanger 11. The oxygenator 10 can be a membrane oxygenator with membranes made, for example, of polypropylene or polyethylene. The heat exchanger 11 can comprise a stainless steel coil or a plurality of hose sections.

[0019] A patient's blood is circulated via lines 12 and the oxygenator 10 using a pump 13. The blood is oxygenated in the oxygenator 10 and cooled or heated as desired using the heat exchanger 11. The blood in the Fig. The system shown in Figure 1 can be part of a heart-lung machine, an extracorporeal membrane oxygenation (ECMO) device, or a miniaturized extracorporeal circulation (MECC) device. The oxygenator 10 can be a membrane oxygenator.

[0020] A heat exchange medium is supplied from a reservoir 20 to the heat exchanger 11 of the oxygenator 10 via lines 21 using a pump device 22. After heat exchange with the patient's extracorporeal blood circulation, the heat exchange medium is returned to the reservoir 20. The heat exchange medium can be, for example, water or glycerin. A thermoelectric heating / cooling device 14 is integrated into the Fig. In the embodiment shown in Figure 2, the heating / cooling device 14 is directly connected to the reservoir 20 for heating or cooling the heat exchange medium. For example, the heating / cooling device 14 can be arranged in or on the reservoir 20. The [description of the] Fig. The embodiment shown in 3 differs from the one shown in Fig. In the example shown in Figure 2, a further heat exchanger 23 is used to heat or cool the heat exchange medium stored in reservoir 20. This heat exchanger is connected to a heating / cooling device 14 via a thermal connection 24. In the Fig. In the embodiment shown in Figure 3, the heating / cooling device 14 comprises a cooling module with Peltier elements 14a and a heating module with a heating coil. These modules can also be arranged in the configurations shown in the Fig. 1 and Fig. The two examples shown are provided for.

[0021] The in Fig.The embodiment shown in Figure 3 can be obtained by retrofitting existing conventional systems or can be entirely newly constructed. Advantageously, this embodiment features thermoelectric heating / cooling devices 14, in particular with Peltier elements, thereby enabling reliable operation with virtually no maintenance required for the heating / cooling device 14. Indeed, prior art held the misconception that the heat exchanger 11 of the oxygenator 10 could only be operated via a heat exchange medium. However, it has been shown that direct heat transfer via a thermal connection element without the use of a heat exchange medium is possible to reliably cool or heat the blood of an extracorporeal blood circulation system.

[0022] It should also be mentioned that the heating / cooling device 14 of the embodiment described above can be used to heat or cool other fluids besides the patient's blood. For example, a cardioplegia solution administered to protect or immobilize the heart muscle can be heated or cooled using the heating / cooling device 14.

Claims

[1] A system for extracorporeal blood circulation, with an oxygenator (10) comprising a heat exchanger (11) designed to heat or cool blood from a patient's extracorporeal blood circulation; a reservoir (20) designed to store a heat exchange medium and connected to the heat exchanger (11); and a thermoelectric heating / cooling device (14); wherein the thermoelectric heating / cooling device (14) is connected to the reservoir (20) by means of a further heat exchanger (23) and is designed to heat or cool the heat exchange medium in the reservoir (20) by means of the further heat exchanger (23). [2] System according to claim 1, wherein the reservoir (20) is connected to the heat exchanger (11) via hoses and / or pipes (21). [3] System according to claim 2, further comprising a pump (22) connected to the hoses and / or pipes (21). [4] System according to one of the preceding claims, in which the thermoelectric heating / cooling device (14) comprises at least one Peltier element (14a) and / or at least one heating coil (14b). [5] System according to one of the preceding claims, in which the heating / cooling device (14) comprises a cooling module with a plurality of Peltier elements (14a) and a heating module with at least one heating coil (14b). [6] System according to one of the preceding claims, further comprising a device for supplying a fluid to the patient's blood, in particular a cardioplegia solution, and wherein the heating / cooling device (14) is connected to the device for supplying the fluid and is configured to heat or cool the fluid, for example the cardioplegia solution. [7] System according to any of the preceding claims, wherein the system is or comprises a heart-lung machine, an extracorporeal membrane oxygenation (ECMO) device or a miniaturized extracorporeal circulation (MECC) device.

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