Temperature-Regulation Apparatus

Abstract

The invention provides a temperature-regulation apparatus with a segmented metal-containing layer. The metal-containing layer has an electrically insulating coating and a plurality of mutually electrically insulated planar metal segments to increase insulation by reducing thermal emissivity whilst minimizing the hazards of an electrically conductive layer. The temperature-regulation apparatus may comprise a blanket which may be used to actively supply temperature regulated air for regulating the temperature of a subject, in which case it includes at least one port, or it may be used to passively maintain the temperature of a subject, or it may comprise a temperature-regulation garment.

Claims

1. A temperature-regulation apparatus comprising a sheet, the sheet comprising a metal containing layer between electrically insulating coating layers, the metal-containing layer comprising one or more metal-containing regions, the or each metal-containing region comprising a plurality of mutually electrically insulated planar metal segments.

2. A temperature-regulation apparatus according to claim 1 wherein the or each metal-containing region comprises more than 100 mutually electrically insulated planar metal segments.

3. A temperature-regulation apparatus according to claim 1 wherein the segments each have, on average (mean) an area of less than 1000 mm.sup.2 and/or wherein the segments each have on, average (mean) a thickness of less than 1 μm.

4. A temperature-regulation apparatus according to claim 1 wherein the segments are separated by at least 0.1 mm.

5. A temperature-regulation apparatus according to claim 1 wherein the segments occupy 90% or more of the surface area of the sheet.

6. A temperature-regulation apparatus according to claim 1 wherein the metal segments comprise tessellating shapes, said shapes being equally spaced.

7. A temperature-regulation apparatus according to claim 1 wherein the segments of one metal-containing region differ in size and/or spacing and/or shape from at least one or each other metal-containing region.

8. A temperature-regulation apparatus according to claim 1 wherein the apparatus is a forced air warming product.

9. A temperature-regulation apparatus according to claim 1 wherein the apparatus is a temperature-regulation blanket.

10. A temperature-regulation apparatus according to claim 9 wherein the temperature regulation apparatus comprises an underbody, configured such that a portion of the apparatus is suitable for use beneath a subject.

11. A temperature-regulation apparatus according to claim 1 wherein the temperature regulation apparatus further comprises an additional sheet, the additional sheet being sealedly attached to the said sheet, thereby defining a chamber therebetween, the temperature regulation apparatus further comprising an inlet port, wherein the additional sheet is air-permeable.

12. A temperature-regulation apparatus according to claim 1 wherein the insulating coating(s) on one or both sides of the metal containing comprises layers of polypropylene (PP), polyethylene (PE), polyurethane (PU), and/or adhesives, optionally wherein the insulating coating(s) on one or both sides of the metal containing layer are in contact with each other in the spaces between said segments.

13. A temperature-regulation apparatus according to claim 1 wherein the insulating coatings on both sides of the metal segments are in contact with each other in the spaces between said segments.

14. A temperature-regulation apparatus according to claim 1 wherein the metal segments are aluminium.

15. A temperature regulation apparatus according to claim 1 wherein the apparatus comprises a temperature-regulation garment.

16. A temperature regulation apparatus according to claim 15, wherein the garment comprises a hospital gown.

Description

DESCRIPTION OF THE DRAWINGS

[0023] An example embodiment of the present invention will now be illustrated with reference to the following Figures in which:

[0024] FIG. 1 is a plan view of an example embodiment wherein the temperature-regulation apparatus comprises a blanket;

[0025] FIG. 2 is a plan view of an example embodiment wherein the temperature-regulation apparatus comprises a blanket, with a plurality of distinct metal-containing regions;

[0026] FIG. 3 is a cross-section through a basic temperature-regulation apparatus;

[0027] FIG. 4 is a cross-section through a temperature-regulation apparatus further comprising an additional sheet sealedly attached to the temperature-regulation apparatus, thereby defining a chamber, as inflated;

[0028] FIG. 5 is a more detailed example cross-section through a temperature-regulation apparatus;

[0029] FIG. 6 is a front view of an example embodiment wherein the temperature-regulation apparatus comprises a garment; and

[0030] FIG. 7 is a back view of an example embodiment wherein the temperature-regulation apparatus comprises a garment.

DETAILED DESCRIPTION OF AN EXAMPLE EMBODIMENT

[0031] With reference to FIG. 1, a temperature-regulation apparatus according to the invention is a blanket in the form of a sheet (1). The sheet (1) has a metal-containing layer (2) with one or more distinct metal-containing regions (5) (FIG. 2 is a diagram of an example of a temperature-regulation blanket with multiple distinct regions (5)). Each region (5) has at least 100 planar metal segments (3), with spaces (4) in between adjacent segments (3). Electrically insulating coating layers (6) surround the metal containing layer (2) and these coating layers (6) are in contact with each other in the spaces (4) in between adjacent segments (3), as can be seen in FIG. 3, which is a cross-section through a basic temperature-regulation blanket.

[0032] Each metal segment (3) covers, on average, an area of less 1000 mm, is less than 0.05 μm thick, and is separated from adjacent segments (3) by at least 0.2 mm. Combined, the metal segments (3) cover at least 90% of the total surface area of the blanket. The segments (3) tessellate (they are rhomboid in shape) and are evenly spaced apart.

[0033] The metal-containing layer (2) of the blanket is thermally insulating in use because it reflects heat back towards a subject. In this way the temperature of the subject can be passively maintained. The spaces (4) between the segments (3) ensure that each segment (3) is electrically insulated from the segments (3) adjacent to it. The segments (3) themselves are each small enough that the capacitive charge imparted to a segment (3) during a defibrillation procedure is too small to overcome the permeability of the coatings (6), thus preventing any uncontrolled discharge.

[0034] Suitable dimensions for the planar metal segments are found according to the following equation, in which A.sub.segment is the area of an individual segment (3), A.sub.impact is the area of a potential burn due to an uncontrolled discharge, p is the energy density of such an uncontrolled discharge, d is the thickness of the insulating coatings (6), ε is the permittivity of free space, K is the relative permittivity and V is the voltage applied during a defibrillation procedure.

[00001]$A_{\mathrm{segment}}=\frac{2A_{\mathrm{impact}}\rho d}{\mathrm{.Math.}\kappa V^2}$

[0035] Further to this, suitable dimensions for the spaces (4) between adjacent planar metal segments (3) may be found according to the following equation, in which δ is the spacing between adjacent segments (3), V is the voltage applied during a defibrillation procedure and h is the dielectric strength of the insulating coatings (6).

[00002]$\delta =\frac{V}{h}$

[0036] For example, in a typical defibrillation procedure a voltage, V, of 5000 V is used. In an example case where the insulating coatings (6) have a dielectric strength, h, this would imply the choice of a distance, δ, of at least 5000/h, between adjacent segments (3). For example, if such a temperature regulation blanket were intended for use during a 5000 V defibrillation procedure, and the dielectric strength of the coatings was 20 MV/m, the distance between adjacent metal segments would be at least 0.25 mm.

[0037] The metal in the metal-containing layer (2) is aluminium and is sheet transferred onto a plastic surface such as a polypropylene (PP) (11), polyethylene (PE) (13) or polyurethane (PU) (17) substrate. The insulating coatings (6) are made up of multiple layers of PP (11), PE (13) and PU (17) and are joined to each other, and to the metal-containing layer (2), with adhesives (16). One skilled in the art will appreciate that other electrically insulating materials may be used in place of PP (11), PE (13) and/or PU (17).

[0038] Because of the coatings (6) the blanket cannot conduct electricity through its plane and because of the spaces (4) between the segments (3) the blanket cannot conduct electricity across its plane. As a result, the blanket is safer than other known blankets with a metal containing region that do not feature either insulating coatings or mutually insulated metal segments, since the risks of fire, burning and/or electrocution are reduced when the blanket is used around electrical appliances or defibrillation equipment.

[0039] With reference to FIG. 4, which shows a cross-section through a temperature-regulation blanket of the general type shown in FIG. 3, the blanket also has an additional sheet (9). This additional sheet (9) is attached to the first sheet (1), to form a chamber (8). The two sheets are held together via fastening means (10) and the first sheet (1) has an inlet port (7). In this configuration, the temperature-regulation blanket can be used as a forced-air temperature-regulation blanket. The fastening means may be welds between the first sheet and the additional sheet.

[0040] The chamber (8) can be filled with temperature-regulated air via the inlet port (7) (which has a port connector for the attachment of a hose, for example, for supplying temperature-regulated air). The temperature-regulated air can slowly leave the chamber (8) via the additional sheet (9), which is porous and thus air-permeable.

[0041] This configuration of the temperature-regulation blanket allows active control of the temperature of a subject (8) by regulating the temperature of the air which is supplied into the chamber and which is forced through the porous additional sheet towards the subject. This is advantageous in the treatment of hypo- or hyperthermia. The additional sheet (9) may in some embodiments be detachable from the temperature-regulation blanket, should active control of the subject's temperature not be necessary.

[0042] FIG. 5 is a more detailed example cross-section through a temperature-regulation blanket of the general type shown in FIG. 3. Here it can be seen that the insulating coating (6) has layers of PU (17), PP (11) and PE (13), as well as adhesive (16), a sealing treatment (12) and a binding treatment (18). It can also be seen that the additional sheet (9) has layers of PE (13) and PP (11) as well as a binding treatment (14). These layers combine to make an electrically insulating coating layer (6) that has a dielectric strength great enough to prevent the flow of electricity through or across the blanket, as well as preventing uncontrolled discharge.

[0043] In a further example embodiment, the temperature-regulation apparatus (1) comprises a garment, as shown in FIG. 6. In such an example, the garment takes the form of a hospital gown for a subject to wear. The gown has sleeves (18), an access panel for use during surgery (19) and fastening means (20), as shown in FIG. 7, such as ties or buttons. The temperature of a subject wearing the gown could be passively controlled while the subject moved around, or, if the subject was stationary and the inlet ports (7) were in use for the supply of temperature regulated air, the temperature of the subject could be actively controlled.