Stand-alone blood warmer

Abstract

Systems, methods, and devices for warming and delivering blood and plasma to a patient may include a body, an infusion sleeve coupled to the body and surrounding a volume, and a control panel disposed on the body. A power source is in electronic communication with the control panel, and the power supply may be a battery located external to the body. A heater is in electronic communication with the battery and is disposed adjacent an interior surface of the infusion sleeve. The heater includes a plurality of heating elements and a plurality of temperature sensors configured to measure a temperature from each of the plurality of heating elements. The power delivered to each heating element may be adjustable in response to the temperature of the heating element or an estimated temperature of a blood or plasma bag.

Description

[0001] Cross - Reference to Related Applications

[0002] This application claims the benefit of U.S. Provisional Patent Application No. 63 / 408,779, filed Sep. 21, 2022, which is incorporated herein by reference in its entirety.

[0003] Government Licensing Rights

[0004] This invention was made with government support under FA8629-20-C-5023 awarded by the U.S. Air Force, Air Force Life Cycle Management Center (“AFLCMC”). The government has certain rights in the invention. Technical Field

[0005] The present disclosure relates to thermal management for the transport and administration of blood perfusion and, more particularly, to warming blood. Background Art

[0006] Medical conditions may not always occur under ideal conditions, and when they do, there may not be a hospital nearby. In the field, patients may encounter situations that require emergency treatment with advanced technologies that are typically only available in hospitals or treatment facilities. An injured individual may be treatable by blood perfusion, for example, in a hospital or other facility capable of maintaining donor blood.

[0007] However, due to temperature, climate, or other environmental factors, some technologies of modern medicine may not be available in the field. Blood is temperature sensitive. During transport prior to perfusion, refrigeration systems are typically used to preserve blood. However, frozen blood is too cold to be used for perfusion.

[0008] Prior to transfusing blood to a patient, the blood is typically warmed to a suitable temperature. Available warmers tend to be disposable, which requires complete or partial replacement after warming a single dose of donor blood. Other warmers may be bulky and suitable for use in hospitals or other fixed locations. Still other warmers tend to warm the blood unevenly, resulting in inconsistent temperatures of the overall warmed blood. Summary of the Invention

[0009] Various embodiments relate to blood warming and delivery devices. The blood and plasma warming device of the present disclosure may include a body, an infusion sleeve coupled to the body and enclosing a volume, and a control panel disposed on the body. A power source is in electronic communication with the control panel. A heater may be in electronic communication with a battery and disposed adjacent an inner surface of the infusion sleeve. The heater includes a plurality of heating elements and a plurality of temperature sensors configured to measure the temperature of each of the plurality of heating elements.

[0010] Various embodiments include an electronic controller configured to control the voltage, current, or power delivered to a heating element in response to the measured temperature of the heating element from the plurality of heating elements. The electronic controller may be configured to control the voltage delivered to a heating element from the plurality of heating elements in response to the estimated temperature of the bag in the volume. The manifold may be in fluid communication with the infusion sleeve and include an inlet for receiving a hose. The manifold may deliver air from the hose into the infusion sleeve to inflate the infusion sleeve. The battery may be located outside the body. The pressure sensor may be in electronic communication with the control panel and configured to measure the air pressure in the infusion sleeve.

[0011] Various embodiments of the warming device include an infusion sleeve surrounding a volume, wherein the infusion sleeve is inflatable to reduce the volume. The heater may be disposed adjacent to the inner surface of the infusion sleeve and may include a plurality of heating elements. A plurality of temperature sensors may be configured to measure the temperature of each heating element from the plurality of heating elements.

[0012] In various embodiments, a heating element from the plurality of heating elements is disposed adjacent to the volume and includes a thermistor trace disposed adjacent to the inner surface of the infusion sleeve. The electronic controller may be configured to control the voltage delivered to the heating element in response to the temperature of the heater measured by the thermistor trace. The electronic controller may also be configured to control the voltage delivered to the heating element in response to the estimated temperature of the bag disposed in the volume. The estimated temperature may be based on the temperature of the heater measured by the thermistor trace. The pressure sensor may be configured to measure the air pressure in the infusion sleeve. The infusion balloon may be in fluid communication with the infusion sleeve.

[0013] Various embodiments include a method of warming blood or plasma using a warming device. The method may include the step of inserting a bag of a cooled product into a volume defined by the infusion sleeve. The heater may be disposed around the inner surface of the infusion sleeve. The infusion sleeve is inflated to a first pressure to press the heater against the bag. Heat is applied to the bag by the heater to warm the cooled product. The method further includes inflating the infusion sleeve to a second pressure to push the warmed product out of the bag.

[0014] The embodiment includes the step of coupling the infusion hose to the bag after applying heat to the bag and before inflating the infusion sleeve to push the warmed product out of the bag. The first pressure may be in the range from 150 mmHg to 300 mmHg. The heater may be powered by a battery that is in electronic communication with the heater. The method may automatically adjust the voltage delivered to the heater in response to the temperature measured at the heater. The method may also adjust the voltage delivered to the heater in response to the estimated temperature of the cooled product. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The subject matter of the present disclosure is particularly pointed out and distinctly claimed at the end of the specification. However, a more complete understanding of the present disclosure may be best obtained by reference to the detailed description and claims in conjunction with the accompanying drawings, in which like numerals designate like elements.

[0016] Figure 1A and 1B FIG. 1 illustrates a perspective view of a blood warming and delivery device according to various embodiments.

[0017] Figure 2 FIG. 2 illustrates a control panel of a blood warming and delivery device according to various embodiments.

[0018] Figure 3 FIG. 3 illustrates a perspective sectional view of a blood warming and delivery device according to various embodiments.

[0019] Figure 4 FIG. 4 illustrates a side sectional view of a blood warming and delivery device defining a heating volume according to various embodiments.

[0020] Figure 5 FIG. 5 illustrates a schematic view of a heater of a blood warming and delivery device according to various embodiments.

[0021] Figure 6 FIG. 6 illustrates an arrangement of heating elements and sensors of a blood warming and delivery device according to various embodiments. DETAILED DESCRIPTION

[0022] The following detailed description is intended to provide several examples that will illustrate the broader concepts set forth herein, but is not intended to limit the invention or its application. Additionally, the invention is not intended to be bound by any theory presented in the foregoing background or the following detailed description.

[0023] The present disclosure relates to battery-powered portable blood and plasma warming devices. These devices are suitable for military or civilian use. The warming devices of the present disclosure can operate without water for melting. An infusion kit can be used in the warming device for sterile delivery. The single-unit blood warmer (SUBW) of the present disclosure can repeatedly warm plasma or blood bags with reusable electronics, which is different from devices that operate with disposable electronics.

[0024] In various embodiments, the blood warming device of the present disclosure is a blood warming and plasma melting device that includes an integrated pressure infuser. The blood warmer of the present disclosure warms blood products before infusion to prevent the recipient from experiencing hypothermia. The SUBW device is suitable for use by healthcare professionals in hospital, clinic, field, and transport environments. The SUBW is capable of operating in harsh environments exposed to rain, dust, rough handling, and extreme temperatures and humidity.

[0025] The SUBW device can use multiple heaters to achieve rapid and uniform heating applications. A sensor array can be arranged around the SUBW device to enable independent evaluation and control of the heaters. The sensors can indirectly measure the temperature of the heaters or the blood bags.

[0026] Reference Figure 1A and 1B show the SUBW 100 according to various embodiments. Figure 1A includes a depiction of the device 100 including the protective layer 103, and Figure 1B a depiction of the device 100 with the protective layer 103 removed. The SUBW 100 includes an infusion sleeve 102 coupled to a body 104. The body can act as a housing for holding and protecting electronics and pneumatics and as a rigid support member for maintaining the shape of the flexible infusion sleeve 102. The infusion sleeve 102 holds the blood bag 108. The blood bag 108 can be inserted into the infusion sleeve 102 by sliding in from the top or bottom of the infusion sleeve 102. The heater 106 is arranged around the inside of the infusion sleeve 102. The heater 106 can be close to or in contact with the blood bag 108 to transfer heat from the heater 106 to the blood bag 108. The heater 106 can be flexible and can include thermally conductive materials such as copper, polyimide, flexible circuits, multi-layer flexible circuits, or other flexible materials and combinations of materials capable of transferring heat. The heater 106 generally generates resistive heat by dissipating electrical energy. The infusion sleeve 102 can be inflatable to apply pressure to the blood bag 108 or to push the heater 106 closer to the blood bag 108. For example, the infusion sleeve 102 can be pressurized to 150 mmHg - 300 mmHg to facilitate heating.

[0027] The infusion sleeve 102 can be made of a flexible material. For example, the infusion sleeve can be made of plastic or rubber. The infusion sleeve 102 can be surrounded by or can include a protective layer 103, which includes a protective material disposed around the outer surface of the infusion sleeve to protect the infusion sleeve 102 from being punctured, cut, worn, or other damage that may inhibit operation. The protective material of the protective layer 103 can include wear-resistant or cut-resistant fabric, canvas, synthetic fiber, aramid fiber, rubber, plastic, woven metal, or other materials suitable for protecting the infusion sleeve 102. The infusion sleeve 102 defines an airtight cavity to facilitate inflation through a pneumatic channel leading into the body 104. The body 104 can hold the edge of the infusion sleeve 102. A valved manifold or a valved pipe fitting can be held in the body 104 to facilitate inflation and deflation of the infusion sleeve 102.

[0028] In various embodiments, the body 104 can be rigid or semi-rigid to hold electronic devices and pneumatic components. The body 104 can thus be made of plastic, metal, rubber, or other materials suitable for holding electronic devices and pneumatic components. The body 104 includes a control panel 110, which can further include input and output mechanisms for outputting data and controlling the operation of the SUBW 100. The body 104 houses a battery and a power input 112 for receiving a charging device to charge the battery in some embodiments. In some embodiments, the battery is located outside the body 104. The SUBW 100 can be compatible with a 120V or 240V charging device, which adapts the electrical output in the form of alternating current to suitable direct current for charging. For example, an adapter can deliver 24 volts of direct current from an alternating current power supply to the SUBW 100 for charging or operation. In another example, the SUBW 100 can receive power between 12VDC and 30VDC at the power input 112.

[0029] In various embodiments, the SUBW can be compatible with an infusion kit to facilitate infusion from a blood bag 108 within the SUBW 100. A hose 122 can be coupled to the body 104 through a mating interface 124. An infusion balloon 120 is coupled to the hose 122 to deliver pressurized air through the hose 122 into the pneumatic components housed in the body 104 and into the infusion sleeve 102 to inflate the infusion sleeve 102. The infusion sleeve can apply a compressive force to the blood bag 108 in response to inflation. The compressive force applied by the infusion sleeve 102 can push the warmed blood from the blood bag 108 through the hose 126 to the patient.

[0030] Now refer to Figure 2, showing a control panel 110 according to various embodiments. The control panel 110 includes a display 200 for printing operation-related information. The display 200 can be an LED, LCD, OLED, or other type of screen suitable for outputting information about the operation of the SUBW 100. The display 200 can be configured to display the temperature of the heater 106, the temperature of the blood bag 108 (of FIG. 1), the pressure of the infusion sleeve 102, the remaining time of the heating operation, the remaining time of the infusion operation, or other information related to warming and delivering blood or plasma.

[0031] In various embodiments, the control panel 110 can include one or more buttons 202. The buttons 202 enable control of the SUBW 100. The buttons 202 can cycle through the operation settings or display settings of the SUBW 100. The buttons 202 can open and close the power delivery circuit that delivers electricity to the heater 106, which can use a resistive heating element to convert electricity into heat. The bridge 212 can house traces or electrodes that selectively deliver power to the heating element in the heater 106.

[0032] In various embodiments, the control panel 110 can also include indicator lights. The indicator lights can display battery charge level, errors, power status, or other information. The SUBW can include a speaker for generating an audible alarm in response to detecting an abnormal operating condition. Alarms and warnings can be silenced for 120 seconds at startup to allow the SUBW 100 to reach its nominal operating condition without issuing false alarms or warnings. Abnormal operating conditions can include low battery power, unacceptable high or low temperature detected on the heater 106, charging failure, or other abnormal operating conditions typical of battery-operated devices.

[0033] In various embodiments, the body 104 can include a mating interface 204 to hold the infusion sleeve 102. The depicted mating interface 204 includes ridges 208 that extend parallel to the edge of the body 104. The protrusions 206 can be oriented perpendicular to the ridges 208 to increase the rigidity and strength of the mating interface 204. The mating interface 124 firmly receives and firmly holds the mating edge 210 of the infusion sleeve 102. The mating interface 124 can be a clamp, channel, groove, or other mating interface suitable for coupling and holding the infusion sleeve 102 relative to the body 104 in place. Electronic and pneumatic components can thus be transferred from the body 104 to the infusion sleeve 102 and held in a substantially fixed position relative to the infusion sleeve 102. The body 104 defines an opening 114 for hanging the SUBW 100. A hanger, belt, hook, rod, or other hanging device can pass through the opening 114 to support the SUBW 100 in a hanging position. In embodiments having a protective layer 103, the opening 114 can be defined by the protective layer 103.

[0034] Reference Figure 3 , SUBW 100 is shown with the body 104 sectioned to expose the electronic and pneumatic components. The body 104 holds the manifold 300 via a valve member 302 that extends into the infusion sleeve 102. The manifold can deliver or release air relative to the infusion sleeve 102 to inflate or deflate the infusion sleeve. A hose 122 is in fluid communication with the manifold to deliver pressurized air (e.g., from a manual pump) into the infusion sleeve 102. The electronics 304 coupled to the manifold 300 can include valve controls, valves, pressure sensors, and other mechanical or electrical components that interface with the air delivery and release system.

[0035] In various embodiments, the body 104 can hold a printed circuit board 306 that interacts with electronic components such as a battery, sensors, processors, memory, or a control panel 110. A substrate 307 can be disposed within the body 104 substantially parallel to the printed circuit board 306. In some embodiments, the substrate 307 can be a printed circuit board, memory, or other electronic device. The control panel 110 can include indicator lights 308 and 310 that can indicate battery charge level, errors, power status, or other information.

[0036] Reference Figure 4 And continuing with reference Figure 3 , the bridge 212 can carry electrical power from a battery in the body 104 through conduits such as traces, wires, or electrical terminals in the printed circuit board 306 or substrate 307 to the heater 106. The bridge 212 can thus include a pair of electrodes or traces for each independently controllable heating element of the heater 106. The heater 106 can be disposed around the inner diameter of the infusion sleeve 102. In other words, the heater 106 can be disposed on opposing inner surfaces of the infusion sleeve 102. The infusion sleeve 102 can include an end 406 that is welded, coupled, fixed, or otherwise constrained to enclose a volume 312 that has an open top and bottom to receive the blood bag 108 (of FIG. 1).

[0037] In various embodiments, the manifold 300 includes an air inlet 404 adapted to mate with the hose 122. The air inlet 404 receives air for delivery through the valve member 302 into the infusion sleeve 102. Although in many embodiments, the inflation balloon 120 (of FIG. 1) contains a check valve in fluid communication with the air inlet 404, the valve member 302 can include a check valve in fluid communication with the air inlet 404 to restrict air from escaping through the air inlet 404. A pressure relief valve can be in fluid communication with the manifold 300 to selectively release air from the infusion sleeve 102. In some embodiments, the pressure relief valve is coupled to or integrally formed with the manifold (e.g., at Figure 3in the valve member 302). The overpressure valve discharges air in response to high pressure in the infusion bag 102. The overpressure valve can be actuated mechanically or electronically by manual user selection, by the electronic control 408, or by mechanical configuration.

[0038] Now referring to Figure 5 , a heater 106 according to various embodiments is shown. The heater 106 can include a plurality of heating elements 504 (numbered 21 to 40). Each heating element can have a negative lead 500 and a positive lead 502. The leads can be traces embedded in or disposed on the heater 106. Although any number of independently controllable heating elements can be used, the heater 106 is depicted as having 20 independently controllable heating elements.

[0039] In various embodiments, the SUBW 100 can include two heaters 106. For example, a SUBW using two heaters 106 can have forty independently controllable heating elements. Each heating element can include a thermistor for measuring the temperature at the heating zone. The heat measured from the thermistor can be used to reduce or increase power delivery via the positive lead 502 and negative lead 500 corresponding to the thermistor.

[0040] For example, the SUBW 100 using 40 heating elements and 40 sensors can include two heaters 106 arranged as shown in Figure 5 to selectively deliver power to the heating elements. The SUBW 100 can deliver more power to the raised portion of the infusion sleeve 102. An accelerometer or position sensor can be used to determine the orientation of the SUBW 100 and the infusion sleeve 102. A thermistor can also be used to detect the lowest position of the infusion sleeve 102 to detect the coldest part of the blood bag 108, since the coldest part is the lowest relative to gravity during heating. The SUBW 100 can use the heaters 106 to maintain the desired heat level at each heating zone.

[0041] Although an example of 20 heating elements 504 per heater 106 is given, each heater 106 can have any number of heating elements 504. The SUBW 100 can use the heating elements 504 to keep the entire heating plate at a substantially uniform temperature. Compared to a heater using a single heating element, multiple independently controllable heating elements can enable the SUBW 100 to more evenly maintain the desired temperature across the heater 106. For example, the heating elements 504 can be maintained at 45°C, 46°C, 47°C, 48°C, 49°C, 50°C, 51°C, or 52°C.

[0042] In various embodiments, ( Figure 4The electronic control 408 can test whether the circuit system and traces are operating properly. Each heating element 504 and its corresponding positive trace 502 and negative trace 500 can be tested to ensure that current flows through each heating element as expected in response to an applied voltage, current, or power. The voltage or current control circuit system can be tested by determining whether the temperature change of the heating element 504 matches the expected change that occurs in response to the selected amount of energy delivered to the heating element 504. An alarm or error can be issued in response to detecting a malfunctioning electronic device.

[0043] The heater 106 rapidly warms the blood or plasma bag 108 because the heating elements 504 are arranged in a grid on each side of the bag 108. The SUBW 100 can deliver different amounts of energy to each heater element 504 (i.e., each section of the grid). The amount of energy delivered is based on the convection detected in the bag, which is measured by the temperature change measured by the thermistors located on each heating element 504 (i.e., at each section of the grid). The SUBW 100 sends more heat to the cooler parts of the bag 108 and thus warms the bag 108 faster than a single heater.

[0044] Now refer to Figure 6 , a diagram showing a heating configuration 600 used in a blood warmer according to various embodiments. The heating configuration 600 includes heating elements 602 disposed on opposite sides of the cooled blood. The heating elements 602 include heater traces 604 disposed on the inner surface of the heating elements 602. The inner surface of the heating elements 602 can be adjacent to the blood bag 108 and oriented to face the blood bag. The heater traces can thus be disposed between the blood bag 108 and the heating elements 602.

[0045] In various embodiments, a thermal sensor can be disposed on the outer surface of the heating element 602. The outer surface of the heating element 602 can be oriented to face away from the blood bag 108. In this regard, the outer surface of the heating element 602 can be adjacent to the inner surface of the infusion sleeve 102 (not shown) and oriented to face the inner surface. The heating element 602 receives current carried along the heater trace and generates heat. The heat generated by the heating element 602 penetrates inwardly towards the blood bag 108 and outwardly towards the thermistor trace 606 and the infusion sleeve 102. The thermistor trace 606 measures the temperature on the outward-facing surface of the heating element 602. A separate thermistor trace 606 and heater trace 604 can be added for each heating element (as Figure 5 shown).

[0046] In various embodiments, the inflatable bladder 610 of the infusion sleeve 102 (of FIG. 1) is inflatable to urge the heater 602 toward the blood bag 108. A thin layer 612 of plastic, rubber, or other flexible material may be disposed between the heater 602 and the blood bag 108. The thin layer 612 is typically coupled to or integrally formed with the inflatable bladder 610 of the infusion sleeve 102. The infusion sleeve 102 may thus define a plurality of chambers that include the inflatable bladder 610 and the region between the thin layer 612 and the inflatable bladder 610 for the heater 106. The thin layer 612 protects the heater 602 from environmental conditions and tends to hold the heater 602 in place around the Figure 3 volume 312 of). The thin layer 612 is thin such that heat can be transferred across the thin layer 612 into the bag 108.

[0047] The thermistor trace 606 is disposed external to the blood bag 108. The temperature measured at the thermistor trace 606 can be used to estimate the temperature of the blood or plasma 608 within the blood bag 108. The thermistor trace 606 is in electronic communication with the thermistor 607 to measure the temperature. The temperature measurement of the blood bag 108 can be based on the thermal resistance of the blood bag 108, the thermal resistance of the thin layer 612, the energy in the heating element 602, and the temperature measured by the thermistor 607. For example, the blood temperature b can be estimated as b = t – cv 2 rp, where t is the temperature at the thermistor trace 606, v is the heater voltage, p is the pulse width modulation (PWM) rate, r is the resistance, and c is a constant. The constant c can be determined based on the air loss and the thermal resistance of the plastic material of the blood bag 108.

[0048] The SUBW 100 can control the power delivered to the heating element 602 in response to the estimated temperature of the blood 608 near the heating element 602. For example, the SUBW 100 (of FIG. 1) can maintain the voltage across the heating element 602 to achieve the desired blood temperature b. The SUBW can maintain the voltage v = sqrt((t – b) / (crp)), where sqrt is the square root function. The voltage corresponding to the measured temperature t can also be held in a look-up table stored in an EPROM, RAM, or other memory suitable for access by a processor in the SUBW100 (of FIG. 1) or Figure 4 other electronic control 408 of). In this regard, Figure 4 the electronic control 408 of) can calculate or look up the voltage to be delivered to the heating element 602 based on the temperature measured at the thermistor trace 606.

[0049] In various embodiments, the SUBW 100 can operate in harsh pre-hospital environments and during air and ground transportation because the SUBW 100 can continuously monitor blood or plasma temperature and can be adjusted to hot or cold environments. For example, the SUBW 100 can operate in environments from -10°C to 40°C, from -15°C to 45°C, or from -20°C to 50°C. The SUBW 100 can also operate from 0 to 5000 meters, from -1000 meters to 6000 meters, or from -2000 meters to 7000 meters relative to sea level.

[0050] The blood warmer and SUBW device of the present disclosure can operate without disposable electronics and infusion bags. The devices of the present disclosure can thus continuously warm blood or plasma as long as sufficient power is available. Relative to some competing products, the devices of the present disclosure are also portable, where the SUBW 100 weighs only up to 1 pound. The weight can be further reduced by using lightweight materials and manufacturing techniques.

[0051] The blood warmer and SUBW device of the present disclosure can also work in any orientation, which enables reliable use in a bumpy ambulance. The user does not need to spend valuable time checking the device orientation before warming and delivering the blood. The devices of the present disclosure also heat blood or plasma faster than competing devices, where the SUBW 100 warms a bag in about 10 minutes. The SUBW 100 also supports faster infusion flow rates and heats the blood before infusion for faster treatment. Blood and plasma can be warmed using the SUBW 100 before administration, and the SUBW 100 can support rapid bolus infusion of all warmed products to increase the chances of survival. The SUBW 100 effectively warms both blood and plasma for delivery to the patient.

[0052] Benefits, other advantages, and solutions to problems have been described herein with respect to specific embodiments. Additionally, the connecting lines shown in the various figures contained herein are intended to represent exemplary functional relationships and / or physical couplings between various elements. It should be noted that many alternative or additional functional relationships or physical connections may exist in an actual system. However, the benefits, advantages, solutions to problems, and any element that may cause any benefit, advantage, or solution to occur or become more pronounced should not be considered a critical, essential, or fundamental feature or element of the invention.

[0053] Accordingly, the scope of the present invention will not be limited by anything other than the appended claims, and references in the appended claims to an element in the singular are not intended to mean "one and only one" (unless expressly so stated), but rather "one or more." Further, in instances where the phrase "A, B, or C" is used in the claims, it is intended that the phrase be interpreted to mean that A may exist alone in an embodiment, B may exist alone in an embodiment, C may exist alone in an embodiment, or any combination of elements A, B, and C may exist in a single embodiment; for example, A and B, A and C, B and C, or A and B and C.

[0054] References to "one embodiment," "an embodiment," "an example embodiment," etc., indicate that the embodiment described may include a particular feature, structure, or characteristic, but every embodiment may not necessarily include the particular feature, structure, or characteristic. Moreover, such phrases do not necessarily refer to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is submitted that it is within the knowledge of one of ordinary skill in the art to implement such feature, structure, or characteristic in connection with other embodiments, whether or not explicitly described. After reading this specification, one of ordinary skill in the relevant art will know how to implement the present disclosure in alternative embodiments.

[0055] Moreover, no element, component, or method step in this disclosure is intended to be dedicated to the public, whether or not the element, component, or method step is expressly recited in the claims. The claim elements herein are not to be construed under the provisions of 35 U.S.C. 112(f) unless the element is expressly recited using the phrase "means for." As used herein, the term "comprises," "comprising," or any other variation thereof is intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

Claims

1. A warming device, which comprises: a main body; an infusion sleeve, which is coupled to the main body and encloses a volume; a control panel, which is disposed on the main body; a power source, which is in electronic communication with the control panel; a heater, which is in electronic communication with a battery and is disposed adjacent to an inner surface of the infusion sleeve, wherein the heater comprises a plurality of heating elements; and a plurality of temperature sensors, which are configured to measure the temperature of each heating element from the plurality of heating elements.

2. The warming device according to claim 1, which further comprises an electronic control, which is configured to control the voltage delivered to the heating element in response to the measured temperature of the heating element from the plurality of heating elements.

3. The warming device according to claim 1, which further comprises an electronic control, which is configured to control the voltage delivered to the heating element from the plurality of heating elements in response to the estimated temperature of a bag in the volume.

4. The warming device according to claim 1, which further comprises a manifold, which is in fluid communication with the infusion sleeve and comprises an inlet for receiving a hose.

5. The warming device according to claim 4, wherein the manifold delivers air from the hose into the infusion sleeve to inflate the infusion sleeve.

6. The warming device according to claim 4, wherein the power source comprises a battery located outside the main body.

7. The warming device according to claim 4, which further comprises an overpressure valve for selectively releasing air from the infusion sleeve.

8. The warming device according to claim 1, which further comprises a pressure sensor in electronic communication with the control panel, the pressure sensor being configured to measure the air pressure in the infusion sleeve.

9. A warming device, which comprises: an infusion sleeve, which encloses a volume, wherein the infusion sleeve is inflatable to reduce the volume; a heater, which is disposed adjacent to an inner surface of the infusion sleeve, wherein the heater comprises a plurality of heating elements; and a plurality of temperature sensors, which are configured to measure the temperature of each heating element from the plurality of heating elements.

10. The warming device according to claim 9, wherein the heating element from the plurality of heating elements is disposed adjacent to the volume and comprises a thermistor trace disposed adjacent to the inner surface of the infusion sleeve.

11. The warming device according to claim 10, which further comprises an electronic control, which is configured to control the voltage delivered to the heating element in response to the temperature of the heater measured by the thermistor trace.

12. The warming device according to claim 10, which further comprises an electronic control, which is configured to control the voltage delivered to the heating element in response to the estimated temperature of a bag disposed in the volume, wherein the estimated temperature is based on the temperature of the heater measured by the thermistor trace.

13. The heating device according to claim 9, further comprising a pressure sensor configured to measure the air pressure in the infusion sleeve.

14. The heating device according to claim 9, further comprising an infusion balloon in fluid communication with the infusion sleeve.

15. A method of using a heating device, which comprises: inserting a bag of a cooled product into a volume defined by an infusion sleeve, wherein a heater is disposed around an inner surface of the infusion sleeve; inflating the infusion sleeve to a first pressure to press the heater against the bag; applying heat to the bag through the heater to warm the cooled product; and inflating the infusion sleeve to a second pressure to push the warmed product out of the bag.

16. The method according to claim 15, further comprising coupling an infusion hose to the bag after applying heat to the bag and before inflating the infusion sleeve to push the warmed product out of the bag.

17. The method according to claim 15, wherein the first pressure is in the range of from 150 mmHg to 300 mmHg.

18. The method according to claim 15, wherein the heater is powered by a battery in electronic communication with the heater.

19. The method according to claim 15, further comprising automatically adjusting the voltage delivered to the heater in response to a temperature measured at the heater.

20. The method according to claim 15, further comprising automatically adjusting the voltage delivered to the heater in response to an estimated temperature of the cooled product.

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