Valved catheter

Abstract

A valved catheter is provided which includes a slit that opens readily in both directions either when a fluid is caused to flow from the interior to the exterior thereof or when a fluid is caused to flow from the exterior to the interior thereof, and that prevents inadvertent closure thereof from the opened state. The valve includes an openable slit that penetrates from the inner surface to the outer surface of a distal end section of a valved catheter with a closed distal end, and edge portions on the two sides of the slit are formed along the direction in which the valved catheter extends. The slit includes a linear shape in the cross-section of the distal end section of the valved catheter that extends in a position away from a center line “c” that passes through the center of the valved catheter in parallel with this center line “c” whereupon, either one of the edge portions deforms more readily than either one of the other edge portions.

1 - 6 . (canceled) 
     
     
         7 . A catheter comprising:
 a tubular body having an open proximal end portion and a dome-shaped distal end, the tubular body defining a valve proximal to the distal end, the valve including a pair of edge portions defining a slit extending longitudinally along the tubular body and extending between an inner surface of the tubular body and an outer surface of the tubular body; and   a contrast-imparting material extending along an entire length of the tubular body, excluding the dome-shaped distal end of the tubular body, wherein a portion of the contrast imparting material is adjacent to the slit.   
     
     
         8 . The catheter of  claim 7 , wherein the contrast imparting material extends parallel to the slit. 
     
     
         9 . The catheter of  claim 7 , wherein the contrast imparting material extends along an interior of one edge portion of the pair of edge portions. 
     
     
         10 . The catheter of  claim 7 , wherein one edge portion of the pair of edge portions is adjacent to the contrast imparting material, and the one edge portion adjacent to the contrast imparting material is less readily deformable than the other of the pair of edge portions. 
     
     
         11 . The catheter of  claim 7 , wherein the tubular body includes a polyurethane resin and the contrast imparting material has a hardness greater than the hardness of the polyurethane resin. 
     
     
         12 . The catheter of  claim 11 , wherein the contrast imparting material prevents the transmission of X-rays therethrough. 
     
     
         13 . The catheter of  claim 12 , wherein the contrast imparting material is barium or tungsten. 
     
     
         14 . The catheter of  claim 7 , wherein the dome-shaped distal end is softer than the open proximal end portion of the tubular body. 
     
     
         15 . The catheter of  claim 7 , wherein the dome-shaped distal end is silicon or polyurethane. 
     
     
         16 . A method of delivering medical fluid to a patient, the method comprising:
 inserting a catheter into the patient's body such that a slit, defined by a pair of edge portions of a tubular body of the catheter, is disposed in a vein;   irradiating a contrast imparting material adjacent to one of the pair of edge portions defining the slit; and   confirming the position of a distal end section of the catheter in the vein based on irradiation of the contrast imparting material.   
     
     
         17 . The method of  claim 16 , further comprising delivering a medical fluid to the vein through the slit. 
     
     
         18 . The method of  claim 16 , further comprising extracting blood from the vein through the slit. 
     
     
         19 . The method of  claim 16 , wherein inserting the catheter into the patient's body comprises making an incision in a subclavian vein of the patient, inserting the catheter into the subclavian vein, through the incision in the subclavian vein, and passing the distal end section of the catheter into the patient's superior caval vein. 
     
     
         20 . The method of  claim 16 , wherein the contrast imparting material extends along an entire length of the tubular body, excluding a dome-shaped distal end of the tubular body. 
     
     
         21 . The method of  claim 16 , wherein the tubular body includes a polyurethane resin and the contrast imparting material has a hardness greater than a hardness of the polyurethane resin.