Paracentesis device having multiple detachable components

Abstract

The invention described herein relates to an improved device for paracentesis procedures, such as thoracentesis. The device comprises a cannula assembly, a reinsertible valve assembly, and catheter assembly, wherein the cannula assembly is removably attached to the valve assembly, and the valve assembly is removably attached to the catheter assembly. The device may include an externally viewable indicator revealing the relative positions of the cannula assembly components. The device can further comprise a locking mechanism which controls the movement between cannula assembly components and is activated and deactivated by the coupling of the cannula assembly to the valve assembly. The device improves the precision and safety of its handling, and offers the practitioner several aspiration alternatives while maintaining separation of the internal and external patient environments.

1 . A device for use in paracentesis comprising:
 a cannula assembly comprising
 an inner cannula having an internal lumen and at least one lateral opening located proximal to its distal end, 
 an outer cannula adapted to accommodate said inner cannula within, and 
 cannula assembly housing, said inner cannula being movable relative to said outer cannula; 
   a valve assembly comprising
 a valve housing, 
 interior chamber, 
 reinsertible valve positioned within said chamber, and 
 a lateral access port, said valve assembly adapted to removably attach to said cannula assembly and to accommodate a portion of said cannula assembly when placed within, 
 wherein said reinsertible valve is configured to sealably engage at least one of said inner cannula and outer cannula; and 
   a catheter assembly comprising
 a flexible catheter having an internal lumen and 
 at least one opening, said catheter assembly connected with said valve assembly and adapted to accommodate a distal portion of said cannula assembly placed within. 
   
     
     
         2 . The device according to  claim 1  wherein said inner cannula is biased so as to extend a distal tip of said inner cannula beyond a distal end of said outer cannula. 
     
     
         3 . The device according to  claim 1  wherein said cannula assembly further comprises an externally viewable indicator which reveals a position of said inner cannula relative to said outer cannula. 
     
     
         4 . The device according to  claim 1  wherein said cannula assembly further comprises a locking mechanism controlled by the coupling of said cannula assembly to said valve assembly. 
     
     
         5 . The device according to  claim 1  wherein said flexible catheter comprises a predetermined resting state configuration different from a substantially linear configuration. 
     
     
         6 . The device according to  claim 5  wherein said pre-determined resting state configuration is a coil. 
     
     
         7 . The device according to  claim 6  wherein said catheter comprises a plurality of lateral openings oriented toward a center of said coil. 
     
     
         8 . The device according to  claim 1 , wherein said reinsertible valve is comprised of an elastic material. 
     
     
         9 . The device according to  claim 1 , wherein said reinsertible valve is comprised of rubber. 
     
     
         10 . The device according to  claim 1 , wherein said reinsertible valve is selected from the group consisting of a slit valve and a centrally perforated diaphragm. 
     
     
         11 . The device according to  claim 1 , wherein said catheter assembly further comprises an adaptor associated with a proximal end of said flexible catheter and configured for releasable attachment to said valve assembly. 
     
     
         12 . The device according to  claim 11 , wherein said adapter includes a threaded surface. 
     
     
         13 . The device according to  claim 1 , wherein a surface of said flexible catheter is treated with a lubricity enhancing substance. 
     
     
         14 . A device for use in paracentesis comprising:
 a cannula assembly comprising
 an inner cannula having an internal lumen and at least one lateral opening located proximal to its distal end, 
 an outer cannula adapted to accommodate said inner cannula within, and 
 a cannula assembly housing, said inner cannula being movable relative to said outer cannula; 
   a valve assembly comprising a reinsertible valve therein;   wherein a proximal portion of said valve assembly is configured to removably attach to a distal portion of the cannula assembly housing;   wherein said valve assembly accommodates a distal portion of said cannula assembly when placed within; and   wherein said valve assembly is configured such that said reinsertible valve remains stationary with attachment and removal of said cannula assembly.   
     
     
         15 . A cannula assembly for use in paracentesis comprising:
 an inner cannula including an internal lumen and at least one lateral opening located proximal to its distal end;   an outer cannula adapted to accommodate said inner cannula within;   an outer cannula hub maintaining a proximal portion of said outer cannula;   a cannula assembly housing, said inner cannula being movable relative to said outer cannula;   a valve assembly comprising a reinsertible valve therein; and   an externally viewable indicator revealing, through said outer cannula hub and said cannula assembly housing, a position of said inner cannula relative to said outer cannula.   
     
     
         16 . The cannula assembly according to  claim 15  wherein said externally viewable indicator comprises an indicia associated with said inner cannula and viewable through said cannula assembly housing. 
     
     
         17 . The cannula assembly according to  claim 15 , further comprising a locking mechanism controlled by a coupling of said cannula assembly to said valve assembly. 
     
     
         18 . The device according to  claim 15  wherein said inner cannula is biased so as to extend a distal tip of said inner cannula beyond a distal end of said outer cannula. 
     
     
         19 . The device according to  claim 15  wherein said cannula assembly further comprises an externally viewable indicator which reveals a position of said inner cannula relative to said outer cannula. 
     
     
         20 . The device according to  claim 15  wherein said cannula assembly further comprises a locking mechanism controlled by the coupling of said cannula assembly to said valve assembly.