WO2009006517A2

WO2009006517A2 - Medical table surface and pads

Info

Publication number: WO2009006517A2
Application number: PCT/US2008/069005
Authority: WO
Inventors: John R. Mangiardi
Original assignee: Optimus Services, Llc
Priority date: 2007-07-03
Filing date: 2008-07-02
Publication date: 2009-01-08
Also published as: WO2009006517A3

Abstract

A method of and apparatus for heating a patient, such as to maintain or restore normothermia, on an operating room table while monitoring the temperature of said apparatus for heating said patient and optionally while monitoring the temperature of said patient is disclosed.

Description

MEDICAL TABLE SURFACE AND PADS

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of the provisional application no. 60/947,752 filed 03 July 2007 and the complete content of this application is incorporated by reference. FIELD OF INVENTION This invention relates generally to a method of and apparatus for heating a patient, such as to maintain or restore normothermia, on an operating room table while monitoring the temperature of said apparatus for heating said patient and optionally while monitoring the temperature of said patient. BACKGROUND OF THE INVENTION A number of methods exist for the purpose of warming a patient during surgery or for post-operative care. US Pat. No. 6,719,780 to Salmon is a device which heats a patient by using an infrared radiant element to provide a beam of radiation. While this device discloses that the complete apparatus may be located in an unobtrusive position such that it does not interfere with the surgical team, the device is nonetheless bulky, must be orientated over the patient thereby reducing proper normal lighting of the patient and also reducing the number of lines of sight and access to the patient. Other heating means, such as the use of convection currents or central air-conditioning also have numerous drawbacks. Such means will also warm the surrounding environment excessively and result in overheating of the surgical or hospital room staff and will also result in excessive energy usage. Air convection units are also bulky and take up considerable valuable space in the operating room, requiring extended wires and heating hoses that create obstacles to free movement around the patient during surgery. Because of lack of real-time local patient temperature feedback from theses heating units, it is possible for the patient to suffer localized overheating and exposure to burn injury, for example as may occur during cross-clamping of a supplying arterial source to a limb during vascular surgical procedures.

Because of the deficiencies of the prior art, there is a need for a device that efficiently, safely, quickly, and with minimal footprint provides a means for warming a patient to normothermic temperatures. Further, there is a need for a device that maintains the strict hygiene requirements of a hospital environment, and provides real-time feedback of local skin temperatures.

SUMMARY AND OBJECTS OF THE INVENTION

As such, it is an object of this invention to overcome or minimize the abovementioned disadvantages. At least one or more of the above objects are met in whole or in part by the present invention. Additional objects are apparent by the following description and claims. The present invention is a table comprising a solid surface having pads affixed on the top of said solid surface, said pads comprising at least one surface comprising a cavity wherein at least one said cavity comprises wires adapted to transmit an electrical current such that transmittal of said electrical current through said wires raises the temperature of said wires, and wherein said pads are adapted to transmit the thermal energy created by said transmittal of said electrical current through said wires to said solid surface and to the surface of said pads. In one embodiment of the invention, the table comprising pads provides a minimal footprint.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention can best be understood in connection with the accompanying drawings. It is noted that the invention is not limited to the precise embodiments shown in the drawings, in which: FIg. 1 is cross-sectional schematic of one embodiment of the invention in which a patient is lying on a series of pads disposed on a solid surface which is disposed on or part of a table.

Fig. 2 demonstrates one embodiment of the invention detailing an operation of a control circuit. BRIEF DESCRIPTION OF REFERENCE NUMERALS

100 Pad or Pads; 102 Solid Surface; 104 Patient; 106 Table Support; 108 Thermistor; 110

Control Circuit

DETAILED DESCRIPTION OF THE INVENTION

As can be seen in the simple schematic shown in Fig. 1, a patient 104 may be situated onto at least one pad 100. The patient may have only a specific body part resting on a pad 100 such as a head, the torso, arms, or legs while another body part or parts (not shown) may rest directly onto the solid surface 102. The solid surface 102 may comprise a single pad 100 or a series of pads 100 disposed on the solid surface. For example, in one embodiment, a single large pad 100 may be disposed throughout the entire length and width of the solid surface 102 or some lesser portion thereof. Whether a single pad or numerous pads are used, the pad or pads 100 may be disposed on the solid surface in a number of manners. For example, the pads may be affixed permanently to the solid surface. In another embodiment, the pads may be affixed using VELCRO or another fastening means such as with plugs, clips, screws, latches, and so on. In a preferred embodiment, the pads are affixed via magnets. For example, a magnet may be disposed on the four corners of a pad and be attracted to a magnetically reactive substance or substances in the solid surface. Alternatively, the magnet may be in the solid surface and the magnetically reactive substance may be in the pad. The use of a magnet is advantageous because the pads can be easily positioned onto the solid surface in a number of arrangements. Further, magnets inside the pad or solid surface are hygienic and can help maintain sterility. Also, magnets have a long life-cycle and are less prone to failure than traditional latching or securing means. The solid surface itself may be affixed or disposed on another table or support structure 106. The solid surface may be a single large slab or may comprise a number of smaller solid surfaces which are joined together. Such an arrangement is preferred for hospital room usage where the table must be adapted to allow adjustment or orientation of the patient. Small solid surfaces can be joined in numerous manners, including hinges, that allow for the free movement of one solid surface relative to another. In a preferred embodiment, the solid surface is non-porous, has a low dielectric constant (to minimize the accretion of dust and other electro-statically attracted substances), and does not promote bacterial or microbial growth. In another preferred embodiment, the table is made of an acrylic resin and may contain antibacterial substances such as titanium dioxide in order to retard, inhibit, or prevent bacterial growth. The solid surfaces may also be adjoined to another table via a variety of means including an epoxy resin or traditional joining means such as screws, latches, joints, and so on.

The pads may be filled with any type of material conducive to the transmittal of electrical current. Such materials include wire and may include wire made of metals. In one embodiment, copper, nickel, nickel and chromium blends or nickel with chromium coats, or silver wire may be used. A carbon based compound may also be used. Any of the foregoing metals or carbon compounds may also be comprised as a coat on nylon or polyester threads as a suitable pad filling and may even be integrated into the fabric weaving. The fabric weaving may also integrate computer chips and other circuitry such as light emitting diodes ("LEDs"), liquid crystal displays ("LCDs"), alpha-numeric displays, or other outputs to provide means for information processing, input/output control, and signaling.

In another embodiment, an alloy or mixture of metals and optionally non-metals may be used. Such materials may also be filamentous. Such materials may also be weaved into, through, or on the pads. Such materials may also fill the cavity of the pad. In a preferred embodiment, the pads comprise a fibrous material having a high resistance. A specific advantage of using fibrous or filamentous materials having a high resistance is that they have been found to allow maximal heat generation while requiring only minimal voltage. Such fibrous or filamentous materials are therefore preferably selected from the class of such materials having high resistance. Such materials may be admixed or comprise in part materials have a low resistance. The pad's fibrous material is adapted to receive a low voltage such that the risk of electrocution or other electrical harm is minimized and yet provide sufficient thermal output to warm a patient. A low voltage is defined as a voltage at least sufficient to provide a non-negligible warming of the pad but no higher than a voltage which would be considered unsafe if a patient were exposed to said voltage. Finally, the pads may comprise, in addition to electrically conducting materials, non-electrical conducting materials including insulation. In one embodiment, the insulation is adapted to allow maximal conduction of heat. In another embodiment, the insulation is adapted to provide support to the pad such that the pad does not unduly compress when a patient is placed thereon.

The pads also comprise a number of thermistors. These thermistors are adapted to register the heat output of the pad at number of locations. The thermistors may be linked to the electrical system comprising the energy delivering source of the pads such that a high temperature will automatically deactivate the pad or pads. For example, a change in resistance in a thermistor will indicate a change in temperature in the vicinity of the thermistor. A control circuit which is calibrated to the temperature/resistance ratio of the thermistor will determine if the temperature of a thermistor is registering an inordinately high temperature. If so, the control circuit will deactivate heating of the pad or pads. The control circuit can also detect a low temperature and raise the temperature of the pad by increasing the voltage passing through the pad's resistive elements. Fig. 2 indicates such an arrangement. Thermistor 108 sends an electrical signal which varies according the temperature of the thermistor 108 to the control circuit 110. In the expanded view of the control circuit 110, the thermistor reading is checked against a set high temperature point. If it is high, the control circuit 110 may lower the voltage (if the temperature is sub-critical) or stop the voltage entirely (if the temperature is critically high). If the temperature is not high, then the control circuit 110 determines whether the temperature is low. If the temperature is low, the control circuit can raise the voltage directed to the heating elements in the pad to raise the temperature of the pads.

In another embodiment of the invention, some thermistors may be adapted to detect the heat temperature of a pad and transmit such a signal to a readout. Such a readout could be used to read the temperature of the pad. In another embodiment of the invention, some thermistors may be adapted to detect the heat temperature of the outer surface of the pad wherein a patient's body part may rest. The detected heat temperature would be transmitted to a readout which would inform persons of the temperature of that region of the patient. Such a readout may be calibrated to determine the temperature of the patient as a whole. For example, a number of thermistors could detect the temperature of the patient at various points and the collected data temperature could be transformed into a single averaged or calibrated temperature of the patient.

The patient may be human or non-human including mammals. In the foregoing description, certain terms and visual depictions are used to illustrate the preferred embodiment. However, no unnecessary limitations are to be construed by the terms used or illustrations depicted, beyond what is shown in the prior art, since the terms and illustrations are exemplary only, and are not meant to limit the scope of the present invention. It is further known that other modifications may be made to the present invention, without departing the scope of the invention, as noted in the appended claims.

Claims

I claim:

1. A table comprising a solid surface having pads affixed on the top of said solid surface, said pads comprising at least one surface comprising a cavity wherein at least one said cavity comprises wires adapted to transmit an electrical current such that transmittal of said electrical current through said wires raises the temperature of said wires, and wherein said pads are adapted to transmit the thermal energy created by said transmittal of said electrical current through said wires to said solid surface and to the surface of said pads.

2. The table of claim 1 in which a patient has a specific body on at least one said pad.

3. The table of claim 1 in which said solid surface has a single pad disposed on said solid surface.

4. The table of claim 3 in which said single pad extends no more than the entire width and length of the solid surface.

5. The table of claim 1 in which the pads are permanently affixed to said solid surface.

6. The table of claim 1 in which the pads are affixed to said solid surface by a fastening means.

7. The table of claim 6 in which the pads are affixed to said solid surface by magnets.

8. The table of claim 7 in which said magnets are in said solid surface.

9. The table of claim 7 in which said magnets are in at least one said pad.

10. The table of claim 9 in which said magnets are disposed on the four corners of the pad.

11. The table of claim 1 in which said solid surface is disposed on a second table.

12. The table of claim 1 in which said solid surface is affixed on a second table.

13. The table of claim 1 in which said solid surface is comprised of a number of smaller solid surfaces.

14. The table of claim 13 in which said smaller solid surfaces are affixed to at least one other smaller solid surface.

15. The table of claim 14 in which said smaller surfaces are movable relative to at least one other smaller solid surface.

16. The table of claim 13 in which said smaller solid surfaces are adjoined by hinges.

17. The table of claim 1 in which said solid surface is non-porous, has a low dielectric constant, and does not promote bacterial or microbial growth.

18. The table of claim 17 in which said solid surface comprises titanium dioxide.

19. The table of claim 18 in which said solid surface comprises titanium dioxide dispersed evenly throughout said solid surface.

20. The table of claim 17 in which said solid surface is made from acrylic.

21. The table of claim 17 in which said solid surface is adjoined by adjoining means to another table.

22. The table of claim 1 in which the pads are filled with material adapted to transmit said electrical current such that transmittal of said electrical current produces maximal heat generation at low voltage.

23. The table of claim 22 in which said material comprises copper, silver, nickel, nickel and chromium, carbon, and compound mixtures thereof.

24. The table of claim 23 in which said materials are coated onto polyester or nylon.

25. The table of claim 22 in which said material is fibrous.

26. The table of claim 22 in which said material comprises filaments.

27. The table of claim 22 in which said material comprises an alloy.

28. The table of claim 22 in which said material comprises a mixture of metals.

29. The table of claim 28 in which said material further comprises at least one non-metal.

30. The table of claim 22 in which said material is woven into the pads.

31. The table of claim 22 in which said material is surrounded by insulation adapted to provide conduction of heat and also adapted to provide support to the pads.

32. The table of claim 22 in which said material is woven into the pads and packed into the pads.

33. The table of claim 32 further comprising integrated circuits and output devices into said woven material.

34. The table of claim 22 in which said material has a high electrical resistance.

35. The table of claim 22 in which said material is adapted to receive either alternating or direct current.

36. The table of claim 1 in which said pads comprise at least one thermistor.

37. The table of claim 36 in which said pads also comprise a control box adapted to receive a signal from at least one thermistor. 37. The table of claim 37 in which said control box determines whether the temperature of the pad is too high or too low and adjusts the voltage to said pads to compensate.

38. The table of claim 37 in which said control box is adapted to signal average or calibrate a number of thermal readings from at least one pad to output a signal comprising a measurement of the temperature of a patient.

39. The table of claim 1 in which (a) a patient has a specific body on at least one said pad; (b) the pads are affixed to said solid surface by a fastening means; (c) said solid surface is comprised of a number of smaller solid surfaces; (d) the pads are filled with material conducive to the transmittal of electrical current; (e) said smaller surfaces are movable relative to at least one other smaller solid surface; (f) said solid surface is non-porous, has a low dielectric constant, and does not promote bacterial or microbial growth; (g) said material is woven into the pads and packed into the pads and said material is surround by an insulating material adapted to provide conduction of heat and support to the pad; (h) said material has a high electrical resistance; (i) said material is adapted to receive a low voltage such that the risk of electrical harm is minimized and such that the pads provide a non-negligible thermal output; Q) said pads comprise at least one thermistor; (k) said pads also comprise a control box adapted to receive a signal from at least one thermistor; and (1) said control box determines whether the temperature of the pad is too high or too low and adjusts the voltage to said pads to compensate.

40. The table of claim 39 in which said control box is adapted to signal average or calibrate a number of thermal readings from at least one pad to output a signal comprising a measurement of the temperature of a patient.

41. The table of claim 39 in which the pads are affixed to said solid surface by magnets.

42. The table of claim 39 in which said solid surface comprises titanium dioxide.

43. The table of claim 39 in which said solid surface is made from acrylic .

44. A method of using the table of claim 1 comprising the steps of:

(a) placing a patient on top of at least one of said pads;

(b) allowing a control box to adjust the temperature of at least one of said pads to a predetermined set-point; and

(c) allowing said control box to regulate the temperature of at least one of said pads.

45. The method of claim 44 in which an operator reads an output derived from a temperature signal sent from a thermistor and thereby determines the temperature of said patient.

46. A method of using the table of claim 39 comprising the steps of:

(a) placing a patient on top of at least one of said pads;

(b) allowing said control box to adjust the temperature of at least one of said pads to a predetermined set-point; and

(c) allowing said control box to regulate the temperature of at least one of said pads thereby regulating the temperature of said patient.