Apparatus and method for reducing interstitial fluid pressure and enhancing delivery of a therapeutic agent

Abstract

An apparatus, system, and method are provided for reducing interstitial fluid pressure in tissue, particularly in tumors. The apparatus includes an aspiration probe with at least one slit along its body to provide fluid communication between the aspiration probe and the tissue. Suction in the chamber of the aspiration probe generated by a suction source reduces the interstitial fluid pressure. Compared to prior art devices, the geometry of the slit of the aspiration probe is less likely to become blocked. The present invention also includes a cleaning obturator to unclog the slit and a blocking obturator to prevent accumulation of tissue in the aspiration probe chamber when suction is off. The blocking obturator can be made of a number of biocompatible materials, including a material impregnated with a pharmacological agent. In order to enhance delivery of the pharmacological agent or any drug, the present invention also includes a conducting obturator made of an electrically conductive material to serve as an electroporation electrode. In one embodiment, at least a portion of the aspiration probe is made of an electrically conductive material and serves as an electroporation electrode.

What is claimed is:  
     
         1 . An interstitial fluid pressure reducing apparatus comprising: 
 an aspiration probe having a body with an open proximal end and a closed distal end, an interior chamber defined by the body and proximal and distal ends, and at least one elongated slit running along the length of the body and providing fluid communication between the chamber of the aspiration probe and tissue upon insertion of at least a portion of the aspiration probe in tissue;    wherein the proximal end is configured and dimensioned for coupling to a suction source for generating suction in the chamber of the aspiration probe upon connection with the aspiration probe to thereby reduce interstitial fluid pressure of the tissue.    
     
     
         2 . An apparatus as in  claim 1 , further comprising a connection member having a first end configured and dimensioned for removably connecting with the proximal end of the aspiration probe and a second end configured and dimensioned for removably connecting with the suction source.  
     
     
         3 . An apparatus as in  claim 1 , wherein the aspiration probe has a suture ring at the proximal end for securing the aspiration probe to tissue.  
     
     
         4 . An apparatus as in  claim 3 , wherein at least one hole is defined in the suture ring shaped to receive a suture.  
     
     
         5 . An apparatus as in  claim 1 , further comprising a cleaning obturator configured and dimensioned for sliding movement into the chamber through the proximal end of the aspiration probe and having at least one fin engaging the at least one slit upon insertion of the cleaning obturator into the chamber for removing any debris from the slit.  
     
     
         6 . An apparatus as in  claim 1 , further comprising a blocking obturator configured and dimensioned to fit within the chamber to block the at least one slit thereby blocking the fluid communication between the chamber of the aspiration probe and tissue for preventing accumulation of tissue in the chamber.  
     
     
         7 . An apparatus as in  claim 6 , wherein the blocking obturator includes at least one rib configured and dimensioned to block one of the at least one slit.  
     
     
         8 . An apparatus as in  claim 1 , further comprising a conducting obturator configured and dimensioned for sliding movement into the chamber and made of an electrically conductive material for serving as an electrode for electroporation.  
     
     
         9 . An apparatus as in  claim 1 , wherein at least a portion of the aspiration probe is made of an electrically conductive material for serving as an electrode for electroporation.  
     
     
         10 . An interstitial fluid pressure reducing apparatus comprising: 
 an aspiration probe having a body with an open proximal end and a closed distal end, an interior chamber defined by the body and proximal and distal ends, and a plurality of apertures along the body providing fluid communication between the chamber of the aspiration probe and tissue upon insertion of at least a portion of the aspiration probe in tissue, the proximal end being configured and dimensioned for coupling with a suction source for generating suction in the chamber of the aspiration probe upon connection with the aspiration probe to thereby reduce interstitial fluid pressure of the tissue; and    a cleaning obturator configured and dimensioned for sliding movement into the chamber through the proximal end of the aspiration probe and having at least one protrusion engaging the plurality of apertures upon insertion of the cleaning obturator into the chamber for removing any debris from the plurality of apertures.    
     
     
         11 . An interstitial fluid pressure reducing apparatus comprising: 
 an aspiration probe having a body with an open proximal end and a closed distal end, an interior chamber defined by the body and proximal and distal ends, and a plurality of apertures along the body providing fluid communication between the chamber of the aspiration probe and tissue upon insertion of at least a portion of the aspiration probe in tissue, the proximal end being configured and dimensioned for coupling with a suction source for generating suction in the chamber of the aspiration probe upon connection with the aspiration probe to thereby reduce interstitial fluid pressure of the tissue; and    a blocking obturator configured and dimensioned to fit within the chamber to block the plurality of apertures thereby blocking the fluid communication between the chamber of the aspiration probe and tissue for preventing accumulation of tissue in the chamber.    
     
     
         12 . An apparatus as in  claim 11 , wherein the blocking obturator is impregnated with a therapeutically effective amount of a pharmacological agent.  
     
     
         13 . An apparatus as in  claim 12 , wherein the blocking obturator is made of a biocompatible polymer.  
     
     
         14 . An apparatus as in  claim 13 , wherein the polymer is polymethyl methacrylate.  
     
     
         15 . An apparatus as in  claim 12 , wherein the pharmacological agent includes an antibiotic.  
     
     
         16 . An apparatus as in  claim 11 , wherein at least a portion of the blocking obturator is made of an electrically conductive material for serving as an electrode for electroporation.  
     
     
         17 . A system for reducing interstitial pressure of tissue comprising: 
 at least two aspiration probes, each having a body with an open proximal end and a closed distal end, an interior chamber defined by the body and proximal and distal ends, and at least one elongated slit along the body providing fluid communication between the chamber of the aspiration probe and tissue upon insertion of at least a portion of the aspiration probe in tissue;    a suction source for generating suction in the chamber of each of the aspiration probes upon connection with the respective aspiration probe to thereby reduce interstitial fluid pressure of the tissue;    a plurality of connection members, each having a first end configured and dimensioned for removably connecting with the proximal end of one of the aspiration probes and a second end configured and dimensioned for removably connecting with the suction source; and    a manifold having a suction source port for removably connecting with the suction source and a plurality of aspiration probe ports, each for removably connecting with one of the connection members.    
     
     
         18 . A system as in  claim 17 , wherein a chamber is defined in the manifold in fluid communication with each of the aspiration probe ports for collection of aspirated fluid.  
     
     
         19 . A system as in  claim 17 , wherein a valve is operatively associated with each of the aspiration probe ports for selective coupling and uncoupling of the aspiration probe port to the suction source.  
     
     
         20 . A system as in  claim 17 , wherein a plurality of chambers are defined in the manifold, each chamber being in fluid communication with one of the aspiration probe ports for collection of aspirated fluid.  
     
     
         21 . A system as in  claim 17 , wherein a valve is operatively associated with the suction source port for selective coupling and uncoupling to the suction source, the valve allowing retention of pressure generated by the suction source upon uncoupling with the suction source.  
     
     
         22 . A system as in  claim 17 , further comprising a cleaning obturator configured and dimensioned for sliding movement into the chamber through the proximal end of one of the aspiration probe and having at least one fin engaging the at least one slit upon insertion of the cleaning obturator into the chamber for removing any debris from the slit.  
     
     
         23 . A system as in  claim 17 , further comprising at least one drug delivery probe having a body with an open proximal end and a closed distal end, an interior chamber defined by the body and proximal and distal ends, and at least one slit along the body providing fluid communication between the chamber of the drug delivery probe and tissue upon insertion of at least a portion of the drug delivery probe in tissue.  
     
     
         24 . A system as in  claim 23 , wherein at least a portion of at least one of the aspiration probes is made of an electrically conductive material for serving as an electrode for electroporation.  
     
     
         25 . A system as in  claim 17 , wherein each of the aspiration probes has a separately adjustable pressure.