Blood collection device with a handle having a hollow needle

The invention relates to a blood sampling device with a holder which has a with a sharpened cutting edge formed, hollow needle-like needle, which is surrounded by a closed-end, flexible, tube-like valve rubber, wherein the holder is provided with a valve rubber from its outer sheath forth fixing portion.

From US-A 3,585,984 such a blood sampling device with a holder is known, which has a with a sharpened cutting edge formed, hollow needle-like needle. The cannula is surrounded by a closed-end, elastic, tube-like valve rubber with air between the cannula and the valve rubber. The holder has forwardly a dome-like approach, in which a rubber piece with the valve, thickened head or plug dips. This header is thus virtually constitutes a valve rubber from its outer sheath forth fixing portion. The valve rubber is namely in a front region, that is pushed with its thickened head piece form-fitting manner on the cannula and is thus by frictional forces in its interior with respect to the cannula, and on its exterior fixed relative to the holder.

In an area famous for the DE-C 18 12 742 blood sampling device open on one side, tubular holder is used which has a at both ends with a sharpened cutting edge formed, hollow needle-like double needle protrudes the rear end in serving as a guide sleeve holder. While the rear cannula end of the double-edged hollow needle is surrounded by the elastic rubber valve with pneumatic radial, protrudes forward of the forward end of the cannula from the end wall of the holder and serves for insertion into a vein of a patient. The extracted blood in a blood collection tube which has been previously connected from the open end thereof to support the holder. When assembling holder and Blutemtnahmeröhrchen the cutting edge of the rear cannula end penetrates initially to him facing the wall or the bottom of the elastic valve rubber and then an elastic stopper of the blood collection tube, so that ultimately the rear end of the cannula extends into the blood collection tube; the elastic valve rubber is compressed like a harmonica. After sampling and stripping the Blutentnahmeröhrchensvon the holder the valve rubber automatically assumes his rear cannula end sealing final starting position a. The holder could also alternatively be reduced to only one, the cannula having disc, ie the guide sleeve does not need to be present. The support disk could connect in such a case with the cathedral of a cap of the blood collection tube.

Another embodiment of a during venipuncture with a double cannula formed blood sampling device has become known by the DE-U 80 16 927. The double cannula is there a unilaterally open, cylindrical housing with an integrally formed outer cone and a single-edge disposed therein, in situ, the rear end of the cannula forming cannula. On the outer cone a receiving cone of a holder is fitted with an end sharpened cannula or hollow needle so that after joining of these two components there is a double cannula, already described above. With this needle design an adaptation is possible, which allows to connect a standard luer with a blood collection tube. The existing here elastic rubber valve is the hollow needle of the holder or adapter to narrow. It is within the scope of possible applications, such an adapter with Luer cone via a special connection to an example to interface with blood filled tube.

In one known from DE-A 29 03 167 Safety cannula for multiple blood sampling, the resilient, is accordion-together donating when connecting to the blood collection tube valve rubber is in turn arranged with radial air or radial clearance to the rear cannula end of the double needle, ie the valve rubber has over its entire length an outer diameter which is larger than the outer diameter of the cannula or hollow needle.

The blood collection devices at the rear of tube enclosing or enveloping rubber valve makes it possible to fill several blood collection tubes by coupling to the double cannula. In a tight-fitting to the hollow needle valve rubber (. See DE-U 80 16 927) occurs between the needle and the valve rubber inevitable friction on what causes the Ventilgummit too slowly rebounds from the accordion entertainment in the relaxed position; when changing the blood collection tubes in these cases is therefore often unavoidable that gush blood drops from the cannula. This is because the valve rubber, the rear end of the sharpened double cannula can not close fast enough. This will be avoided if the elastic, tube-like valve rubber occupies a radial distance from the needle, that is, these air wrapped (see FIG. DE-A 29 03 167 and DE-C 18 12 742). Because the rubber valve not tightly against the needle, however, the valve rubber arising problems, a secure position in the holder or adapter provided. The rubber valve known from DE-C 18 12 742 blood collection device is therefore formed at its open end with a stop collar which bears against an inner shoulder of the holder and the rest in this position solely due to the friction between the outer surface of the collar and the inner surface the holder is positioned. The valve rubber of known from DE-A 29 03 of 167 double cannula is formed at its open rear end with an outer collar which is inserted into an annular groove of the end wall of the holder. Aside from that, here again, the valve rubber is fastened only by a loose fit in the holder, is also preparing to mount the valve rubber difficulties and requires great skill when threading the elastic valve rubber in the annular groove.

In addition, numerous other fastening techniques for the valve rubber are known, for example, the form-fitting sliding the valve rubber on a cylindrical section in the central region of the cannula (see FIG. DE-A 37 40 269). From EP-A 0,619,096 it has been known to push the valve rubber in its front region on a spherical bead, while in contrast, the WO 95/16395 teaches to evert the valve rubber over a circumferential conical collar with undercuts and there optionally nor to bond. According to EP-A 0,678,279 the valve rubber is mounted with a circumferential collar in a circumferential edge inside the holder and secured by a Plastikeimsatz.

The invention is based is to provide a blood collection device of the type mentioned that enables low installation effort a secure fit of the valve rubber in the holder or adapter the task.

This object is achieved in that the valve rubber-defining of its outside portion of the holder is a deformable clamping element. Herewith is achieved that the valve rubber is not only loose or friction or even by gluing in the holder located but set captive by the inventive deformable clamping element; it can no longer be removed from the cannula and certainly not automatically fall out of the holder. Nevertheless, it is ensured that between the rubber valve and the needle and the rear needle end of the double needle over the entire length of the valve rubber is a radial distance is given so that no friction occurs between these two parts and the elasticity of the Ventilgumis for an immediate closure of the rear can provide cannula end when a blood collection tube is changed; a blood outlet at this point is thus avoided. The preparation of the rubber valve requires no excessive demands on the observance of contours and tolerances as well as any special seals on the inner surface of the valve rubber is required.

Further features and advantages of the invention will become apparent from the following description in which an embodiment of the object of the invention is explained with reference to a holder for a blood collection device, which is designed as open on one side holder having a tubular section as a guide sleeve and a both sides sharpened double cannula having , Nevertheless, the various embodiments described above holder are alternatively also be used, whereby the holder can optionally be formed in one piece with the cannula. From a per se well-known blood sampling device open on one side holder 1 is shown in the single FIGURE, in the end wall 2 a double cannula 3 is secured by for example welding or gluing in the embodiment; can therefore be dispensed with an additional needle holder. The double needle 3 is formed with front and rear of a cutting edge 4, or 5; the rear end of the cannula 6 protrudes into the guide sleeve 7 of the holder 1, while the front end of the cannula 8 projects out of the holder 1 and introduced to the blood in a vein of a patient. For blood collection, the guide sleeve 7 is pushed in a known manner to a corresponding blood collection tube, wherein the cutting edge 5 of the rear needle end 6 of both the bottom 9 of the rear end of the cannula 6 with radial clearance 10 enclosing the valve rubber 11 and an elastic stopper of the blood collection tube, not shown, penetrates, is made to connect to the interior of the blood collection tube.

The elastic, tube-like valve rubber 11 is pushed with its 9 facing away from the bottom open end in a komzentrisch to the guide sleeve 7 in the holder 1 formed on the inside of the end wall 2 clamping element 12th In the Klemmelememt 12 may for example be a circumferentially closed ring or a ring of spaced part segments of or hired its ring segments after Einsteckem the valve rubber against the outer jacket 13 of the valve rubber 11, pressed it and permanently deformed to clamp the valve rubber 11 is or, as illustrated in the lower half of the drawing by the reference numeral 12 'for the clamping element. The open end of the valve rubber 11 thus needs only up to the stop on the inside of the front wall 2 in the annular gap between to be the clamping member 12 is inserted and then is after the forming of one or more clamping elements securely in the holder. 1

The deformation of the clamping element or part of individual clamping elements can be achieved, for example, by a punch having a bore for receiving the rear cannula end 6 including the enveloping these, plugged valve rubber eleventh When the front portion of the bore is funny shaped and has a larger diameter than the sleeve-shaped clamping element 12 or proposed for clamping single clamping elements which respectively the clamping elements with an axial plunger motion over the conical portion of the bore in the outer jacket 13 of the valve rubbers 11 is pressed (see., the reference numeral 12 'in the figure). After removal of the punch, the clamping member 12 remains in this position and clamps the valve rubber 11 captively in the holder. 1