Device for the Extravascular Recirculation of Liquid in Body Cavities

Abstract

Biocompatible liquid is pumped into a body cavity (e.g., subarachnoid space, peritoneum, mediastinum, pleural space) by means of one pump and removed from it by means a second pump, preferably via a double-barreled catheter is used for insertion and removal of the liquid. An optional secondary catheter removes liquid from a distal area of the body cavity. Temperature and pressure are sensed within the cavity and can be controlled by adjusting liquid flow rates. While outside the body, the liquid can be ultraviolet-sterilized, foam fractionated to remove contaminants, oxygenated and pH balanced, cooled or warmed, and augmented with exogenous liquid that may contain drugs.

1 . Apparatus for modulating introduction and removal of a liquid within a cavity of a patient's body, the cavity comprising a cavity outside of blood vessels, the apparatus comprising:
 a catheter configured for insertion into the cavity and introduction and removal of liquid from the cavity;   one or more sensors positionable in the patient's body so as to sense a condition of tissue in the cavity; and   a controlled pumping system operatively coupled to both the catheter and the one or more sensors, the controlled pumping system configured to control introduction and removal of liquid from the cavity so as to maintain a selected tissue condition value.   
     
     
         2 . The apparatus of  claim 1 , the catheter comprising a first lumen for introducing liquid into the cavity and a second lumen for removing fluid from the cavity. 
     
     
         3 . The apparatus of  claim 1 , wherein the one or more sensors are positioned on the catheter. 
     
     
         4 . The apparatus of  claim 1 , wherein the one or more sensors are positioned separate from the catheter and positionable at a location separate from the catheter. 
     
     
         5 . The apparatus of  claim 1  wherein the condition is pressure of surrounding tissues in the cavity. 
     
     
         6 . The apparatus of  claim 1  wherein the condition is tissue temperature. 
     
     
         7 . The apparatus of  claim 1  wherein the catheter comprises a dual lumen catheter. 
     
     
         8 . The apparatus of  claim 1 , further comprising a first receptacle for storing liquid to be introduced into the patient's cavity and a second receptacle for collecting liquid removed from the patient's cavity. 
     
     
         9 . The apparatus of  claim 8 , wherein the first receptacle and second receptacle are coupled so as to allow recirculation of liquid. 
     
     
         10 . The apparatus of  claim 1  further comprising a second catheter configured for removal of liquid from the cavity. 
     
     
         11 . A method of maintaining a liquid condition parameter within a body cavity other than a blood vessel within a patient's body, the method comprising:
 pumping liquid into the cavity;   pumping liquid out of the cavity;   monitoring a parameter of tissue within the body from a sensor disposed within the patient's body; and   controlling at least one of liquid temperature, liquid pressure, and liquid flow rate in response to a tissue condition value measured in the monitoring step.   
     
     
         12 . The method of  claim 11  wherein the monitoring step comprises monitoring temperature of tissue within the body. 
     
     
         13 . The method of  claim 11  wherein the monitoring step comprises monitoring pressure of tissue within the body. 
     
     
         14 . The method of  claim 11  wherein the steps of pumping liquid into the cavity and pumping liquid out of the cavity comprises pumping liquids into and out of the cavity through a single catheter. 
     
     
         15 . The method of  claim 14  wherein the catheter comprises a dual lumen catheter. 
     
     
         16 . The method of  claim 11  wherein the step of pumping liquid out of the cavity comprises pumping liquid out of the cavity through an outflow catheter disposed remote from an inflow catheter through which liquid is pumped into the cavity. 
     
     
         17 . The method of  claim 14  further comprising periodically reversing a flow direction of the liquid to clear the catheter of debris. 
     
     
         18 . A method of controlling fluid flow within a body cavity other than a blood vessel within a patient's body, the method comprising:
 pumping liquid into the cavity with a catheter;   pumping liquid out of the cavity with the catheter;   detecting a blockage at the catheter; and   clearing the blockage from the catheter.   
     
     
         19 . The method of  claim 18  wherein the detecting step further comprises detecting a blockage at an inflow lumen of the catheter. 
     
     
         20 . The method of  claim 19  wherein the clearing step further comprises reversing a flow direction of the inflow lumen of the catheter. 
     
     
         21 . The method of  claim 18  wherein the detecting step further comprises detecting a blockage at an outflow lumen of the catheter. 
     
     
         22 . The method of  claim 21  wherein the clearing step further comprises reversing a flow direction of the outflow lumen of the catheter. 
     
     
         23 . The method of  claim 18  wherein the detecting step further comprises detecting a blockage at both an inflow and an outflow lumen of the catheter. 
     
     
         24 . The method of  claim 18  further comprising monitoring a change in pressure in the cavity, the detecting step further comprising detecting the blockage at the catheter when an expected change in pressure does not occur. 
     
     
         25 . The method of  claim 24  wherein the expected change in pressure comprises a rise in pressure when liquid is pumped into the cavity. 
     
     
         26 . The method of  claim 24  wherein the expected change in pressure comprises a fall in pressure when liquid is pumped out of the cavity. 
     
     
         27 . The method of  claim 18 , the detecting step further comprising monitoring a change in pressure outside preset limits. 
     
     
         28 . The method of  claim 27  wherein the change in pressure is a change in cavity pressure. 
     
     
         29 . A method of inducing therapeutic hypothermia in a patient, the method comprising:
 pumping liquid into a peritoneum; and   maintaining a constant volume of liquid in the peritoneum by continuing to pump liquid into the peritoneum at a rate of approximately 100-150 ml/h to account for absorption of liquid by the peritoneum.   
     
     
         30 . Apparatus for modulating introduction and removal of a liquid within a cavity of a patient's body, the cavity comprising a cavity outside of blood vessels, the apparatus comprising:
 a catheter configured for insertion into the cavity and introduction and removal of liquid from the cavity;   one or more sensors configured to sense a temperature of liquid removed from the cavity; and   a controlled pumping system operatively coupled to both the catheter and the one or more sensors, the controlled pumping system configured to control introduction and removal of liquid from the cavity based on the temperature of the removed liquid.