Abstract: A method of using a catheter system to perform medical procedures is disclosed in which the catheter system includes a guide catheter configured to receive inner catheters therein. The method includes performing initial medical procedures with the catheter system until an original inner catheter located within the guide catheter becomes dysfunctional, wherein (i) the initial medical procedures performed during the initial medical procedures performing step are respectively separated in time by interim time periods, and (ii) the original inner catheter is retained within the guide catheter during the interim time periods.

Abstract: A method of performing dialysis with a catheter system which includes (i) a working catheter having a distal working orifice, and (ii) a guide catheter having a guide lumen and a distal guide orifice is disclosed. The method includes the step of locking the working catheter in an operative position in which (i) the working catheter extends through the guide lumen of the guide catheter and out of the distal guide orifice of the guide catheter, and (ii) the distal working orifice of the working catheter is positioned outside of the guide catheter. The method further includes the step of performing a dialysis procedure including advancing and withdrawing blood through the working catheter while the working catheter is locked in the operative position.

Abstract: A catheter system includes a multi-lumen working catheter having a first distal working orifice and a second distal working orifice. The catheter system further includes a guide catheter having a guide lumen and a distal guide orifice. Also, the catheter system includes a locking mechanism which locks the working catheter relative to the guide catheter in (i) an operative position, and (ii) a stowed position. When the working catheter is locked in the operative position, (i) the working catheter extends through the guide lumen of the guide catheter and out of the distal guide orifice of the guide catheter, and (ii) the first distal working orifice and the second distal working orifice are each positioned outside of the guide catheter.

Abstract: A preferred bag cutting and closing clip is described. The clip includes two elongate members and means for directing the elongate members toward one another to close the bag. The clip also includes cutting means such as serrations effectively positioned on the clip for severing bag portions on one side of the clip from bag portions on another side of the clip while the bag remains effectively closed between the elongate members. A preferred clip also includes the feature of extendability, as well as other highly advantageous design features. A method of closing an open flexible plastic or paper bag and for removing excess bag portions therefrom is also described.