DE3109402A1 - Mandrin for a vein catheter - Google Patents

Abstract

The invention relates to a mandrin (6) for a vein catheter for measurement of the central venous pressure in the upper vena cava, with a flexible plastic tube (1) which is to be introduced into the vein via a cannula and in which the mandrin, which comprises a wire core (6b) and a plastic sleeve (6a) surrounding the latter, is arranged so as to be extractable, the sleeve projecting beyond the front end of the wire core and forming a head part (6c) whose flexibility is higher than that of the remaining mandrin body. The primary new feature is the fact that the head part (6c) projecting beyond the wire core (6b) is about 1.0 to 3.5 cm long.

Description

~ Stylet for a venous catheter "

The invention relates to a stylet for a venous catheter for measurement of central venous pressure in the superior vena cava, with a cannula in The flexible plastic tube to be inserted into the vein, in which the stylet can be withdrawn is arranged, which consists of a wire core and a plastic sheath encasing it consists, which protrudes beyond the wire core at the front end and here with a head part forms higher flexibility compared to the rest of the mandrin body.

A venous catheter is described in DE-GM 75 30 163. This previously known Embodiment has a handle plate for handling and fixing the catheter on, whereby the exact position of the venous catheter can be reproduced without difficulty is. This allows for the same insertion point for the catheter Plastic tubing always has the same length. So the hose needs no longer to be individually adjusted by cutting off the excess length.

The plastic hose is made of very soft material and must be special be flexible in order to easily follow the course of the vein when inserting it into the vein and adjust the fabric gently to be able to. Around the plastic tube to be sealed against leaking blood and air ingress when it is introduced or to close, it is common to have a thread-like tube in the plastic tube To arrange the stylet, which consists exclusively of plastic and is particularly soft is designed to be flexible in order to accommodate the adaptability of the plastic hose when it is introduced into the vein. not to # affect. This stylet is neither intended nor suitable for stiffening or to stabilize. However, due to the lack of guide rigidity, it is very difficult insert the plastic tube into the vein until it reaches its predetermined end position has reached.

Venous catheters with a stylet have also been used consists of a wire core and a plastic sheath encasing it, which the Wire core towers over at the front end and here a headboard with compared to the rest of the mandrel body forms greater flexibility.

Essential when inserting the plastic tube into the vein there is sufficient flexibility of the front end of the plastic tube in the direction of insertion, to ensure here that the plastic tube is inserted in a way that is gentle on the tissue leaves.

The fact that the plastic sheath protrudes beyond the wire core is obtained a particularly flexible head part of the stylet and thus a total Particularly flexible end of the plastic tube that is at the front in the direction of insertion. In the extensive tests, however, there were mainly problems with the correct one Dimensioning of the head part.

The invention is therefore based on the object explained at the outset Mandrin regarding the design of the head part of its plastic tube optimize.

This object is achieved according to the invention in that the wire core The protruding head part is about 1.0 to 3.5 cm long.

When treating adults, it is useful if that Head part is about 1.5 to 3.5 cm, preferably 2.5 cm long. When treating For infants, however, it is advantageous if the headboard is about 1.0 to 1.5 cm long is.

For safety reasons, it is advisable to use a wire core and a plastic cover are glued together.

When handling the venous catheter, there is a risk that the wrong end of the plastic tube is inserted into the cannula or vein will. Such an error, which is dangerous for the health of the patient to exclude, it is advantageous' if the plastic cover on which the head part bearing end is provided with at least one optical marking.

A second marking can also be provided, which corresponds to the attending physician shows how far the plastic tube should be inserted.

In the drawing, an exemplary embodiment is shown in FIG Invention shown. They show: FIG. 1 a vein catheter in perspective Representation and Figure 2 in a greatly enlarged scale in longitudinal section the front End of a stylet.

The venous catheter shown consists of one to be inserted into the vein flexible plastic tube 1, one end of which is larger in an extension piece 2 Diameter passes. Above the junction 3 between the plastic tube 1 and extension piece 2 sits on the latter a grip plate 4, which is approximately wing-shaped is formed and lies in a plane perpendicular to the hose axis.

A fixation plate 5 is pushed onto the plastic tube 1, which is strip-shaped, in a plane perpendicular to the plane of the handle plate 4 and protrudes beyond the plastic tube on both sides. Here is the fixation plate pushed so far onto the plastic tube 1 that it is the connection point 3 to the end piece 2 overlaps somewhat. By simply sticking the two over the ends of the fixation plate protruding beyond the plastic tube with a plaster the venous catheter can be fixed quickly, easily and safely.

Figure 1 shows that in the plastic tube 1 a mandrin 6 is inserted, which protrudes with its rear end from the extension piece 2 and hose 1 can be pulled out of the plastic at the appropriate time. According to FIG. 2, the mandrin 6 consists of a wire core 6b and a sheathing that surrounds it Plastic sleeve 6a, which is the wire core at the front end towers and here forms a head part 6c. This head part shows because of the lack of a wire core Compared to the rest of the mandrin body, it has a considerably higher flexibility. Wire core 6b and plastic sleeve 6a are glued together.

It can also be seen that the plastic sleeve 6a is the head part 6c carrying end is provided with an optical marking 7.

Blank page

Claims (5)

Claims: 1. Stylet for a venous catheter for measuring the central venous pressure in the superior vena cava, with a cannula into the Flexible plastic tube to be introduced into the vein, in which the stylet can be withdrawn is arranged, which consists of a wire core and a plastic sheath encasing it consists, which protrudes beyond the wire core at the front end and here with a head part higher than the rest of the mandrin body. Flexibility forms, d a d u It is noted that the head part protruding beyond the wire core (6b) (6c) is about 1.0 to 3.5 cm long. 2. Stylet according to claim 1 for the treatment of adults, thereby characterized in that the head part (6c) is about 1.5 to 3.5 cm, preferably 2.5 cm long is. 3. Stylet according to claim 1 for the treatment of infants, thereby characterized in that the head part (6c) is about 1.0 to 1.5 cm long. 4. stylet according to claim 1, 2 or 3, characterized in that Wire core (6b) and plastic sleeve (6a) are glued together. 5. Stylet according to one of the preceding claims, characterized in that that the plastic sleeve (6a) at the end carrying the head part (6c) with at least an optical marking (7) is provided.