TUBULAR GUIDING DEVICE FOR INTRODUCING A CATHETER OR TUBE INTO A VEIN OR OTHER TUBULAR CAVITY

Abstract: A tubular guiding device to facilitate the introducing of a catheter or tube into a vein or other tubular cavity is made of a thin and flexible material, so that its cross section can be reduced for inserting in a cannula, by which the device may be inserted in a vein and after removal of the cannula, the guiding device may extend its cross section to guide the insertion of a catheter. In order to ensure the inserting and further working of the guiding device it must be provided with means which ensure a sufficient rigidity in its longitudinal direction.

Description: Tubular guiding device for introducing a catheter or tube into a vein or other tubular cavity. The invention relates to a tubular guiding device to facilitate the introducing of a catheter or tube in a vein or other tubular cavity. Without being specially designed for this purpose, the guiding device is e- specially advantageous by introducing a tube or cathe¬ ter of the kind described in Danish patent No.146 150 into a vein or a tubular cavity. Especially when a catheter during a surgical operation has to be inserted in an internal vein, problems may ap- pear by the opening of the vein and that the catheter during the introducing through this opening may conti¬ nue its movement through the vein in the desired direc¬ tion. It is the object of the invention to provide a guiding device by which these problems are overcome, so that the operation can be made quickly. Irrespective of the guiding device in the following is described in connection with the introducing of a ca¬ theter in a vein, it would be understood that it may al- so be used for other surgical operation as f.inst. in¬ troducing of a catheter in the urethra as well as any other surgical operation, where a tube has to be intro¬ duced into a lumen. OMPI Guiding devices for the present purpose are known from a.o. Danish patent application 2044/82, which describes various constructions of guiding devices, the outer di¬ ameter of which corresponds to the outer diameter of the catheter to be introduced, but which after the in¬ troducing may be dilated in a way that the guiding de¬ vice after the introducing may be drawn back over the inserted catheter. It is the purpose of the present invention to provide a guiding device of the kind referred to, the cross section of which may be considerably changed so that during the introducing it may be placed inside a can¬ nula provided for this purpose, and after removal of the cannula may be used for introducing of the catheter, with a diameter which may be greater than the outside diameter of the cannula. According to the invention this may be achieved by per¬ forming the guiding device as indicated in the charac¬ terizing clause of claim 1. Owing to the small diame- ter of the guiding device in its rolled-up condition and its rigidity in longitudinal direction it may be possible directly to insert the guiding device in ure¬ thra without causing any pein, and then to introduce a catheter with a considerably greater diameter. It would be understood that the guiding device must be made of a thin and elastic material as f.inst. plastic- foil, but in view of its introducing it must have a certain rigidity in longitudinal direction. In order to obtain this the guiding device may as indicated in claim 2 also be provided with a number, f.inst. 3-6 longitudinally placed thin metal wires preferably hair¬ pin-like with its bending at the distal end of the gui- OMP ding device to avoid that the distal ends of the wires during insertion will cut into the wall of the vein. It has a further advantage that the guiding device will be clearly visible on the X-ray picture in the case, where the operation must be carried out inside the body by use of X-ray screening. The use of metal wires will also make it possible to provide the guiding device with a curvature which may be straightened out during the introducing of the devi- ce. Furthermore, this longitudinal reinforcement will have a certain lever-effect which will cause a conical delating of the guiding of a catheter or tube. The invention will now be described by way of an embo¬ diment with reference to the accompanying drawing, wherein Fig. 1 is a sideview of the guiding device according to the invention, Fig. 2 a cross section of the line II-II in Fig. 1 , Fig. 3 a cross section of the guiding device in its rolled-up condition, Fig. 4 a sideview of the distal end of the guiding de¬ vice with inserted metal wire, Fig. 5 the distal end of the cannula in section and Fig. 6 a cross section of the line VI-VI in Fig. 5. Figures 1-4 illustrate an embodiment of a guiding de¬ vice according to the invention consisting of a rather thin-walled tube 1, which f.inst. as shown may be a little conical and possibly at its proximal end provi¬ ded with an outside bead 5 to facilitate securing the guiding device during insertion of the catheter or tube, and further provided with an adequate number, in the present case four longitudinal strengthening ribs 2 to obtain necessary rigidity of the guiding device in its longitudinal direction to enable it to be inserted in the cannula. During this insertion its cross section must be diminished, which f.inst. may be obtained by rolling-up as shown in Fig.3. When the catheter or tube is inserted through the guiding device, its cross section would be extended as shown in Fig.2. The above-named increasing of the rigidity of the guid- ing device in the longitudinal direction may also be obtained by inserting thin metal wires 3 as shown in Fig, 4. For reasons of security these metal wires may be hairpin-like with its bending 4 at the distal end of the guiding device. For introducing the guiding device f.inst. in a vein inside the body may be used a cannula as shown in Fig. 5 and 6. In order to avoid that the cannula during the insertion may cut into and hurt the vein in which it is introduced, its distal end may be temporarily closed by means of a piston-like plug 7 with a reward direc¬ ted and through the cannula placed stick 8 to keep the plug 7 on its place during the insertion and following removing of the plug through the cannula. In order to facilitate the removal of the cannula after the guiding device has been placed, the cannula may be opened at its one side by means of a longitudinal slot 9, which make it possible to remove the cannula trans¬ versely from the guiding device 1. The use of metal wires 3 has the further advantage that the guiding device may be provided with a curvature in order to facilitate its introducing. A substantial ad¬ vantage of the invention is that the guiding device fa- OMPI cilitates the introducing of a catheter or tube in a tubular cavity, and under certain conditions the use of a cannula is superfluous, as the guiding device may be inserted in other ways. OMPI

Claims: C L A I M S . 1. Tubular guiding device to facilitate introducing of a catheter or tube into a vein or other tubular ca¬ vity, c h a r a c t e r i z e d in that it consists of a thin and flexible material, so that it may be rolled-up star-shaped in crosssectional direction to a substantially reduced diameter around longitudinally placed ribs or the like strengthening means to obtain sufficient rigidity to enable its introducing in the tubular cavity. 2. Guiding device as claimed in claim 1, c h a r a c t e r i z e d in that in the wall of the guiding de¬ vice is embedded a number of longitudinal thin metal wires C3) preferably hairpin-like with the bending (4) in the distal end of the guiding device.

Inventors: NISSEN RICHARD BENT, NISSEN, RICHARD, BENT
Applicants: NISSEN RICHARD BENT, NISSEN, RICHARD, BENT
Application year: 1983
Main classification: A61M25
IPC codes: A61M25