Buoyant tip aspiration catheter and methods of use

Abstract

A catheter comprising a flexible elongate tubular member having a lumen communicating with a proximal end and a distal port at a distal end. A chamber, filled with gas or fluid less dense than blood, is mounted at the distal end. Methods of using the aspiration catheter for removing embolic air or gaseous bubbles within a body cavity are also disclosed.

What is claimed is:  
     
         1 . A buoyant tip catheter, comprising: 
 a flexible elongate tubular member having a proximal end, a distal end, and a lumen therebetween, the distal end having a port communicating with the lumen; and    a chamber mounted at the distal end and filled with a first gas,    wherein, during use, the distal end of the elongate tubular member is inserted into a body cavity containing body fluid and a second gas, the distal end is guided to the second gas, and the second gas is removed from the body cavity through the port and lumen.    
     
     
         2 . The catheter of  claim 1 , further comprising an introducer.  
     
     
         3 . The catheter of  claim 2 , wherein the introducer is a cannula.  
     
     
         4 . The catheter of  claim 1 , wherein the first gas is selected from the group consisting of helium, nitrogen, and carbon dioxide.  
     
     
         5 . The catheter of  claim 1 , further comprising a pump operatively connected to the proximal end of the elongate tubular member and communicating with the lumen.  
     
     
         6 . The catheter of  claim 1 , wherein the elongate tubular member is a thin-walled material selected from the group consisting of thermal plastic, polyvinyl chloride, polyolefin, urethane, and PEBAX.  
     
     
         7 . The catheter of  claim 1 , wherein the elongate tubular member further comprises a small wire helically wound to prevent kinking.  
     
     
         8 . The catheter of  claim 1 , wherein the chamber comprises a toroidal balloon disposed about the distal end of the elongate tubular member.  
     
     
         9 . The catheter of  claim 1 , wherein the chamber comprises an olive-shaped balloon disposed about the distal end of the elongate tubular member.  
     
     
         10 . The catheter of  claim 1 , wherein the chamber is a balloon, and wherein the elongate tubular member further comprises an inflation lumen communicating with the balloon.  
     
     
         11 . The catheter of  claim 1 , wherein the chamber further comprises an interior filled with foam.  
     
     
         12 . The catheter of  claim 1 , wherein the body cavity is a blood vessel or heart chamber.  
     
     
         13 . The catheter of  claim 1 , wherein the body fluid is blood.