FR2788222A1 - Medical-surgical drain cannula has orifices in distal end located in spiral grooves to prevent blockages - Google Patents

Abstract

The drain cannula (1) has an axial channel (2) linked to an aperture in its distal end (3) and a series of peripheral apertures (4) round the conical tip (7). The peripheral apertures are located in the base of spiral grooves (6). The proximal end of the cannula has a connector (5) for a suction tube. Preferred Features: The peripheral apertures are located in the base of spiral grooves (6) lying at 20-40 deg to the cannula's axis. The distal end of the cannula can be made from a material with a shape memory effect for use with a stilette-mandrel.

Description

- 1-

  LEFT CARDIO-VENTRICULAR DISCHARGE CANNULA

DESCRIPTION

  The invention relates to a left cardio-ventricular discharge cannula of the type comprising, in its axial part, a channel provided, at its distal end, with a drainage opening; at the periphery of its distal part, a plurality of drainage orifices opening into said channel; at its proximal end, a connector capable of connecting the

  cannula to a suction tube; said cannula being associated with a stylus-

  mandrel capable of being inserted therein to provide it with rigidity

  necessary for its proper positioning in the heart.

  The known cannulas of the genus in question all present the incon-

  major venient related to the bonding of the heart wall against the orifices

  drainage. This results in an irregularity in the aspi-

  ration of blood contained in the cardiac chambers annoying considerably

the work of the surgeon.

  It is with the aim of remedying this major drawback that the applicant has designed a discharge cannula which is essentially characterized in that the peripheral drainage orifices open, outside the cannula, into the bottom of grooves made on the outskirts of

the distal part of said cannula.

  According to various features of the invention: - the grooves are in the form of a spiral; - the distal end of the drainage channel is conical and cross-section

  decreasing from the inside to the outside.

  The characteristics and advantages of the invention will appear

  more clearly on reading the following detailed description of

  least one preferred embodiment thereof given by way of example

  nonlimiting and shown in the accompanying drawings.

  In these drawings: - Figure 1 is a top view of the cannula according to the invention; - Figure 2 is a side view of said cannula; - Figure 3 is a view, in longitudinal section, of the distal part

of the cannula.

  -2- The cannula shown in the figures essentially comprises: - in its axial part, a channel (2) provided, at its distal end, with a drainage opening (3); - at the periphery of its distal part, a plurality of drainage orifices (4) opening into said channel (2); - at its proximal end, a connector (5) capable of connecting the cannula (1)

to a suction tube.

  The cannula is associated with a stylet stylet capable of being inserted therein.

  to give it the rigidity necessary for its proper positioning

in the heart.

  The drainage orifices (4) open, outside the cannula, into the bottom of grooves (6) produced at the periphery of the part

distal of the cannula (1).

  This particular feature aims to avoid sticking of

  the heart wall during aspiration.

  The grooves (6) can be made in the form of a spiral.

  The angle formed by the grooves (6) and the longitudinal generatrices of the cannula (1) is advantageously between 20 and 40 including

including 30.

  This particular feature aims to promote evacuation

of blood flow.

  The material used to make the distal part of the cannula (1) is shape memory such that, when the stylet stylet is introduced into the cannula (1), the grooves (6) are parallel to the

  longitudinal generatrix of said cannula and, when said stylet-

  mandrel is removed from it, the grooves regain their spiral shape. This special feature allows flexible introduction and

  non-traumatic cannula in the heart.

  The distal end (3) of the channel (2) is conical and of decreasing section

  health from the inside out.

  This special feature allows better suction because

  it eliminates competition between blood streams.

  The outer distal end (7) of the cannula is bevelled or rounded in order to allow a better introduction thereof and a reduction -3-

traumatic areas crossed.

  The cannula may include: - a first reference ring (8) indicating the position of the end of the cannula in the left atrium of the heart; a second reference ring (9) indicating the position of said end

in the left ventricle of the heart.

  The cannula can be made of silicone or polyvinyl chloride depending on the flexibility and biocompatibility sought, but

  also depending on the operating technique chosen by the surgeon.

  In the preferred embodiment of the invention: - the cannula has a length of 300 mm, the first ring is located mm from the distal end and the second 50 mm from the first in the proximal direction; - The cannula has an outside diameter of 7 mm and the canal a diameter of 4 mm, the corresponding drainage opening having a diameter of 3 mm; - the grooves, cylindrical fraction, have a diameter of 2 mm and the corresponding orifices have a diameter of 1 mm; - there are 3 grooves;

  - the number of orifices per groove is 6.

  Of course, the invention is not limited to the embodiments described and shown for which other variants can be provided, in particular in: - the nature of the materials used; - the number of grooves and drainage holes; - the dimensions of the various parts of the cannula;

  - the types of stylet chucks used.

-4-

Claims (8)

  1- Left cardio-ventricular discharge cannula (1) of the type comprising, in its axial part, a channel (2) provided, at its distal end, with a drainage opening (3) '; at the periphery of its distal part, a plurality of drainage orifices (4) opening into said channel (2); at its proximal end, a connector (5) capable of connecting the cannula (1) to a suction tube; said cannula being associated with a stylet stylet capable of being inserted therein to provide it with the rigidity necessary for its adequate positioning in the heart;   characterized in that the drainage openings (4) open outwards   laughter of the cannula, in the bottom of grooves (6) made at   periphery of the distal part of the cannula (1).   2- Cannula according to claim 1, characterized in that the   grooves (6) are in the form of a spiral.   3- cannula according to claim 1, characterized in that the material used to produce the distal part thereof is shape memory so that, when the stylet stylet is introduced into the cannula (1), the grooves (6) are parallel to the longitudinal generatrices of said cannula and, when said stylet-mandrel is   removed from it, the grooves return to their spiral shape.   4- cannula according to claim 2 or claim 3,   characterized in that the angle formed by the grooves (6) and the genera-   longitudinal trices of the cannula (1) is between 20 and 40.   - Cannula according to claim 1, characterized in that   the distal end (3) of the channel (2) is conical and of decreasing section   health from the inside out.   6- Cannula according to claim 1, characterized in that   the outer distal end (7) thereof is bevelled or rounded.   7- Cannula according to claim 1, characterized in that it   comprises a first reference ring (8) indicating the position of the end   mite the cannula in the left atrium of the heart.   8- Cannula according to claim 7, characterized in that it   has a second reference ring (9) indicating the position of the end   mite the cannula into the left ventricle of the heart. -5-   9- Cannula according to any one of claims 1 to 8,   characterized in that it is made of silicone.   - Cannula according to any one of claims 1 to 8,   characterized in that it is made of polyvinyl chloride.