(51) Int. Cl.⁷:

A 61 M 39/02

A 61 M 25/04

(19) Federal Republic of Germany

[emblem]

German Patent and Trademark Office

(12) Patent

(10) DE 199 57 402 C1

(21) Filing number: 199 57 402.2-44

(22) Filing date: November 29, 1999

(43) Disclosure date: -

(45) Publication date

of patent grant: August 16, 2001

Opposition may be lodged within three months following publication of grant.

(73) Patent holder: Hankel-Shepherd, Peter, 34260 Kaufungen, DE (74) Representative: Walther, Walther & Hinz, 34130 Kassel

(72) Inventor: Same as the patent holder (56) Documents taken into consideration to evaluate patentability: WO 99 34 859

(54) Port, in particular an Implanted Port with Improved Flow Properties

(57) Port, in particular, an implanted port comprising a housing upper section (30) and a housing lower section (1), where the housing lower section (1) exhibits a chamber (10) with a tangentially positioned outlet (20), and where the chamber (10) exhibits outwardly convex side faces (11), and where the chamber floor (15) resembles, when viewed from the top, the cross sectional area of a cam.

[see figure]

Federal Government Printing Office 06.01 102 133/292/7A 11

DE 199 57 402 C1

Description

The invention relates to a port, in particular an implanted port comprising a housing upper section and a housing lower section, where the housing lower section exhibits a chamber with a tangentially positioned outlet and where the chamber exhibits outwardly convex side edges.

Vascular access systems consist of two main groups - that is, on the one hand, so-called central venous catheters (also known as indwelling catheters) and, on the other hand, so-called port systems. Both systems allow fast access to the vascular system of a patient. The reasons for long term vascular access include, inter alia, the administration of chemotherapeutic preparations or therapeutic preparations for the relief of pain or also for the administration of medications to combat the threats to the vital functions - for example, asthma - or even other applications, for which it is necessary to have continuous access to the blood stream of the patient. Consequently ports are nothing more than containers, which are filled with a medicinal preparation, and which are connected by way of the veins or arteries or the peritoneum to the blood stream of the patient. The ports may be filled by means of catheters. In this case the upper section of the housing exhibits a membrane, which is made, in particular, of silicone, and through which the silicone needle pierces and which automatically seals upon removal of the catheter needle.

A major problem with ports is the risk of the accumulation of so-called "sludge" - thus, blood clots and drug residues. Such sludge clogs the port and promotes the growth of bacteria. At this point there already exist ports, which exhibit essentially round chambers, as compared to the conventional rectangular ports. In this case the three dimensional shape of the chamber corresponds to that of a balloon, which is flattened off on the two opposing sides. This type of port could significantly minimize the accumulation of sludge, but could not totally eliminate it.

The WO 99/34850 discloses ports with varying chamber cross sections. However, none of the chambers that are described in this patent is able to totally eliminate the settling out of "sludge", because the chamber of the port still has locations, in which the rate of flow is too slow to prevent the formation of deposits of blood residues and drug residues.

Therefore, the invention is based on the problem of providing a port, in particular an implanted port, which is described in the introductory part and which can significantly suppress the formation of deposits of sludge.

The invention solves this problem in that the chamber floor resembles, when viewed from the top, the cross sectional area of a cam. That means that the chamber in the port now exhibits the shape of a cam, where the cam exhibits side edges, which are laterally outwards convex. The choice of such a simple shape makes it possible to achieve the goal that the rate of flow in the chamber can be significantly increased, as compared to a known chamber of the state of the art, where the chamber is configured, as viewed from the top, round. The outlet is configured advantageously in the area of the convex side wall of the chamber and, in particular, in the transition from the elliptical section to the circular section in the chamber, which has, when viewed from the top, the shape of a cam. Exactly in this area at the transition from the elliptical to the circular section, the rate of flow is the highest, a feature that means that especially this method will largely decrease the risk of the formation of deposits of blood residues and drug residues.

An additional feature of the invention provides that the chamber floor is configured so as to be outwardly convex in order to be able to provide a higher volume in the chamber. The floor of the port itself is also provided with an outwardly directed convexity, which has the advantage that the port has a better seat on the tissue, with the result that the risk of dislodgment on the tissue is reduced.

In addition, the housing upper section exhibits openings in the area of the edge for fixing on the tissue, in order to further impede the port from migrating.

The invention is explained in detail below through the use of one example with reference to the drawings.

Figure 1 is a side view of the housing lower section, where the hatched lines are omitted.

Figure 2 is a view along the line II-II from Figure 1.

Figure 3 depicts the upper section of the housing.

The first aspect of interest with respect to the invention is the lower section of the housing that is depicted in Figures 1 and 2. The housing lower section, which is marked with the reference numeral 1, shows a housing chamber 10, which exhibits, as stated above, the shape of a cam, when viewed from the top. However, in contrast to the side faces of a cam, which are configured so as to be straight, the side faces 11 in the figures are configured so as to be outwardly convex. This cam-shaped chamber 10 exhibits an elliptical section 12 and a circular section 13. In the area of the transition from the elliptical section 12 to the circular section 13 the outlet 20 is configured in the area of the convex side wall in the chamber. The outlet 20 is positioned in such a manner that it is always located in the area of the maximum rate of flow of the medium, which is rotating in the chamber and which is a mixture of drugs and blood. That means that the attachment of the outlet is attached at the point of transition from the elliptical portion of the cam-shaped chamber to the circular portion of the cam-shaped chamber and continues running at an oblique angle in the area of the circular portion of the chamber.

The floor 15 of the chamber is configured so as to be outwardly convex, in order to provide a somewhat enlarged volume for accommodating the drug.

The floor 2 of the port is also configured so as to be outwardly convex or rather protrudes outwardly, in order to prevent a dislodgment and/or twisting and thus migration of the port on the tissue. In addition, the port itself exhibits a side area 3, which shows a plurality of openings 4 for fixing the port on the tissue. In this case the fixation may also be produced, for example, by sewing. However, in so doing the tissue will also automatically grow through the openings in the port. In addition, the lower section of the port has a thread 7 for accommodating the upper section 30 of the port (Figure 3). The port upper section 30 is configured like a hat and has a thread 31, which is configured in the upper section and matches the thread lug 7 of the lower section of the housing. In the center the upper section of the housing exhibits a membrane 33 made of silicone rubber.

Patent Claims

1. Port, in particular, an implanted port comprising a housing upper section (30) and a housing lower section (1), where the housing lower section (1) exhibits a chamber (10) with a tangentially positioned outlet (20), and where the chamber (10) exhibits outwardly convex side faces (11), characterized in that the chamber floor (15) resembles, when viewed from the top, the cross sectional area of a cam.

2. Device, as claimed in claim 1, characterized in that the outlet (20) is arranged in the area of the convex side wall (11) of the chamber (10).

3. Device, as claimed in claim 2, characterized in that the outlet (20) is configured in the transition from the elliptical section (12) to the circular section (13) of the chamber (10), which has, when viewed from the top, the shape of a cam.

4. Device, as claimed in claim 1, characterized in that the chamber floor (15) is configured so as to be outwardly convex.

5. Device, as claimed in claim 1, characterized in that the floor (2) of the port exhibits an outwardly directed convexity.

6. Device, as claimed in claim 1, characterized in that the housing upper section (30) exhibits a membrane (33).

7. Device, as claimed in claim 6, characterized in that the membrane (33) is made of silicone rubber.

8. Device, as claimed in claim 1, characterized in that the port is made of titanium.

9. Device, as claimed in claim 1, characterized in that the housing lower section (1) in the area of the edge (3) exhibits openings (4) for fixing to the tissue.

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2 sheet(s) of drawings

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- Blank Sheet -

key to the figures

DRAWINGS SHEET

Number: DE 199 57 402 C1

Int. Cl.⁷: A 61 M 39/02

Publication date: August 16, 2001