Apparatus and methods for warming and cooling bodies

Abstract

A flexible heat exchanger is suitable for heating or cooling living subjects or objects. The heat exchanger has a volume having at least one inlet for receiving a heat exchange fluid and at least one outlet. A flexible heat exchange plate that is essentially impermeable to the heat exchange fluid is penetrated by substantially rigid thermally-conductive members. The members provide paths of high thermal conductivity through the plate. The heat exchange fluid may be water.

1 . A flexible heat exchanger comprising: 
 a volume having at least one inlet for receiving a heat exchange fluid and at least one outlet; and,    a flexible front sheet essentially impermeable to the heat exchange fluid, the front sheet carrying a plurality of substantially-rigid members, each of the members comprising an exposed thermally-conductive surface on a thermally-conductive first body on an outside of the front sheet and having a thermally-conductive portion extending from the thermally-conductive first body, through the front sheet, and into the volume,    each of the plurality of members comprising opposed gripping surfaces held firmly against opposed sides of the front sheet.    
   
   
       2 . A flexible heat exchanger according to  claim 1  wherein the volume is defined between the front sheet and a flexible rear sheet.  
   
   
       3 . A flexible heat exchanger according to  claim 2  wherein the rear sheet is shaped to provide indentations at locations that are adjacent to the substantially-rigid members and the thermally-conductive portions of the substantially-rigid members project into the indentations.  
   
   
       4 . A flexible heat exchanger according to  claim 3  wherein wherein the members are arranged in rows to provide a plurality of substantially unbroken lines of the front sheet extending between the rows of the members.  
   
   
       5 . A flexible heat exchanger according to  claim 1  wherein wherein the members are arranged in rows to provide a plurality of substantially unbroken lines of the front sheet extending between the rows of the members.  
   
   
       6 . A flexible heat exchanger according to  claim 4  wherein the members are arranged in an array such that the plurality of substantially unbroken lines of the front sheet includes first and second sets each comprising a plurality of the unbroken lines wherein the unbroken lines of the first set intersect with the unbroken lines of the second set.  
   
   
       7 . A flexible heat exchanger according to  claim 1  having drape.  
   
   
       8 . A flexible heat exchanger according to  claim 1  wherein the volume comprises a channel extending from the inlet to the outlet wherein a cross-section of the channel varies periodically along a length of the channel.  
   
   
       9 . A flexible heat exchanger according to  claim 8  wherein the thermally-conductive members are spaced apart along the channel and the channel includes constricted areas located between the thermally-conductive members.  
   
   
       10 . A flexible heat exchanger according to  claim 8  wherein the channel is a sinuous channel.  
   
   
       11 . A flexible heat exchanger according to  claim 1  wherein the thermally-conductive surface of the first body is spaced outwardly from the outside of the front sheet.  
   
   
       12 . A flexible heat exchanger according to  claim 1  wherein an area of the thermally-conductive surface of the first bodies exceeds a total cross sectional area of the thermally-conductive portions measured where the thermally-conductive portions pass through the front sheet.  
   
   
       13 . A flexible heat exchanger according to  claim 1  wherein the thermally-conductive portions project into the volume past an inside face of the front sheet by distances of at least 3 mm.  
   
   
       14 . A flexible heat exchanger according to  claim 1  wherein the thermally-conductive portions each have a thermal conductivity of at least 50 Wm −1 K −1 .  
   
   
       15 . A flexible heat exchanger according to  claim 1  wherein the thermally-conductive portions each have a thermal conductivity of at least 100 Wm −1 K −1 .  
   
   
       16 . A flexible heat exchanger according to  claim 1  wherein the thermally-conductive portions are made of metal.  
   
   
       17 . A flexible heat exchanger according to  claim 16  wherein the thermally-conductive portions are made of metals selected from the group consisting of: aluminum, copper, gold, silver, alloys of two or more of aluminum, copper, gold, or silver with one another and alloys of one or more of aluminum, copper, gold, or silver with one or more other metals.  
   
   
       18 . A flexible heat exchanger according to  claim 1  wherein the outside of the front sheet is faced with an absorbent fabric and the thermally-conductive portions of the members project through the absorbent fabric.  
   
   
       19 . A flexible heat exchanger according to  claim 1  wherein the plurality of the members covers at least 30% of an area of the outside of the front sheet.  
   
   
       20 . A flexible heat exchanger according to  claim 2  wherein the front and rear sheets are attached to one another in a pattern of attached areas to provide a sinuous channel in the volume, the sinuous channel and extending between the inlet and outlet.  
   
   
       21 . A flexible heat exchanger according to  claim 20  wherein the members are spaced apart along the channel, each of the members is located in a wider portion of the channel and the channel has a plurality of narrower portions spaced apart along the channel, the narrower portions each located between an upstream one of the members and a downstream one of the members.  
   
   
       22 . A flexible heat exchanger according to  claim 1  wherein, for each of the plurality of members, the sheet is received in a groove extending circumferentially around the member.  
   
   
       23 . A flexible heat exchanger according to  claim 1  wherein each of the plurality of members comprises a rivet having a head on the outside of the front sheet and a washer on an inside of the front sheet, the thermally-conductive body comprises a head of the rivet and the front sheet is gripped between the head of the rivet and the washer.  
   
   
       24 . A flexible heat exchanger according to  claim 1  wherein the thermally-conducting surface is either flush with or projects outwardly from an outside surface of the wall.