Infusion systems and methods for introducing fluids into the body within a desired temperature range

Abstract

The invention provides systems and methods for infusing a fluid into a patient. In one exemplary embodiment, a system comprises a volume of fluid and a temperature altering device in close proximity to the volume of fluid. The temperature altering device is employed to heat or cool the volume of fluid to a desired temperature. A positive pressure device is provided to place the volume of fluid under positive pressure while at the desired temperature. A transfer member is further provided to transfer at least some of the fluid into the patient while at the desired temperature.

What is claimed is:  
     
         1 . A system for infusing a fluid into a patient, the system comprising: 
 a volume of fluid;    a temperature altering device in close proximity to the volume of fluid to heat or cool the volume of fluid to a desired temperature;    a positive pressure device to place the volume of fluid under positive pressure while at the desired temperature; and    a transfer member to transfer at least some of the fluid into the patient while at the desired temperature.    
     
     
         2 . A system as in  claim 1 , wherein the temperature altering device comprises a heater, and wherein the desired temperature is within the range from about 36° C. to about 42° C.  
     
     
         3 . A system as in  claim 1 , wherein the temperature altering device comprises a cooler, and wherein the desired temperature is within the range from about 0° C. to about 35° C.  
     
     
         4 . A system as in  claim 1 , further comprising a reservoir for holding the volume of fluid, wherein the transfer member is operably connected to the reservoir, and further comprising a flow regulator to regulate the flow of the fluid from the reservoir and into the transfer member.  
     
     
         5 . A system as in  claim 4 , wherein the flow regulator comprises a controller which regulates the application of pressure from the positive pressure device.  
     
     
         6 . A system as in  claim 5 , wherein the flow regulator regulates both the rate and the volume of fluid removed from the reservoir.  
     
     
         7 . A system as in  claim 4 , wherein the reservoir comprises a compressible bag.  
     
     
         8 . A system as in  claim 1 , wherein the transfer member comprises a length of tubing.  
     
     
         9 . A system as in  claim 1 , further comprising a controller to monitor the temperature of the volume of fluid and to control actuation of the temperature altering device.  
     
     
         10 . A system as in  claim 1 , wherein the temperature altering device comprises a housing having inner walls which define a chamber, wherein the fluid is held within the chamber, and wherein the housing includes temperature altering elements to heat or cool the inner walls of the housing to alter the temperature of the fluid.  
     
     
         11 . A system as in  claim 10 , wherein the temperature altering elements are selected from the group of elements consisting of electrical resistors, chemicals, frozen liquids, heated liquids, heated gases, radio frequency electrodes, and thermoelectric crystals.  
     
     
         12 . A system as in  claim 1 , wherein the positive pressure device comprises a plate and a compressor for moving the plate against the volume of fluid to compress the fluid.  
     
     
         13 . A system as in  claim 11 , wherein the compressor is selected from the group of compressors consisting of springs, hydraulics, and solenoids.  
     
     
         14 . A system as in  claim 1 , wherein the positive pressure device comprises a bladder and a pressure source to expand the bladder against the volume of fluid.  
     
     
         15 . A system as in  claim 1 , wherein the volume of fluid is selected from the group of fluids consisting of blood, saline solutions, drugs, and solutes.  
     
     
         16 . A method for infusing a fluid into a patient, the method comprising: 
 providing a volume of liquid which is at an initial temperature;    altering the temperature of the fluid until the fluid is at a desired temperature; and    pressurizing the fluid while at the desired temperature to introduce the fluid into the patient at the desired temperature.    
     
     
         17 . A method as in  claim 16 , further comprising regulating the pressure applied to the fluid to introduce the fluid into the patient at a predetermined rate and volume.  
     
     
         18 . A method as in  claim 16 , further comprising flowing the pressurized liquid through a tube which is intravenously inserted to the patient to introduce the fluid into the patient.  
     
     
         19 . A method as in  claim 16 , further comprising heating the fluid to the desired temperature which is within the range from about 36° C. to about 42° C.  
     
     
         20 . A method as in  claim 16 , further comprising cooling the fluid to the desired temperature which is within the range from about 0° C. to about 35° C.  
     
     
         21 . A method as in  claim 16 , wherein the temperature altering step comprises placing the volume of fluid into a housing having inner walls which define and chamber and heating or cooling the inner walls to alter the temperature of the fluid.  
     
     
         22 . A method as in  claim 16 , wherein the pressurizing step comprises compressing the volume of liquid with a plate.  
     
     
         23 . A method as in  claim 16 , wherein the pressurizing step comprises inflating a bladder which presses against the volume of fluid.  
     
     
         24 . A method as in  claim 16 , wherein the volume of fluid is selected from the group of fluids consisting of blood, saline solutions, drugs, and solutes.  
     
     
         25 . A method as in  claim 16 , wherein the volume of fluid is held within a compressible bag, and wherein the temperature of the fluid is altered while within the bag.