WO2012139980A1

WO2012139980A1 - Central venous catheter

Info

Publication number: WO2012139980A1
Application number: PCT/EP2012/056344
Authority: WO
Inventors: Domenico Giuseppe DI MARCO
Original assignee: Elvido Medical Technology Srl
Priority date: 2011-04-15
Filing date: 2012-04-05
Publication date: 2012-10-18
Also published as: ITPD20110125A1

Abstract

A central venous catheter, characterized in that it comprises a main catheter (10) constituted by a tubular element (11) provided with at least one balloon (12) that is inflatable by a continuously circulating thermal fluid, provided with a central main lumen (13) and two lumens (14, 15) for feeding and recovering the thermal fluid and with at least one seat (29, 30) for the passage of conductors associated with sensors for measuring functional parameters, an auxiliary catheter (31) being also provided, adapted to be inserted in the central main lumen (13), the auxiliary catheter (31) being provided with at least one central lumen (32) and with seats (41, 42) for the passage of electrical cables of sensors (43, 44) for functional parameters.

Description

CENTRAL VENOUS CATHETER

The present invention relates to a central venous catheter of the type designed to be used in thermal and pharmacological treatments and in treatments for monitoring parameters of a patient.

More particularly, the treatments are a therapeutic hypothermia or a therapeutic heating of the patient's blood.

Correlated to the thermal treatments the catheter according to the invention can be used also in intravenous administration of drugs, as well as for intravenous monitoring of vital parameters.

Catheters of this type are known, for example, from EP 0335022 or

EP 2255725.

These catheters, since they must be able to perform many functions, are very complex and provide a plurality of lumens and of seats for many sensors.

This entire set of lumens and sensors must nonetheless be contained in reduced transverse dimensions, and this makes their production difficult as well as expensive.

In use, however, all the lumens and all the sensors are seldom necessary, and therefore part of these devices remains unused.

In addition, the catheter itself is also relatively rigid and therefore its use may not be easy.

Clearly, the catheter, after being used, incidentally for only a few days, is extracted and cannot be used again, and therefore it is destroyed.

Its destruction is complete, so that no part of it is recoverable, not even the parts that have not been used.

The aim of the present invention is to provide a central venous catheter that solves and overcomes the above-mentioned problems of known catheters.

Within this aim, an object of the invention is to provide a catheter that can be adapted to various types of use, having, for each type, only the lumens and sensors necessary in the pathology to be treated.

Another object is to provide a catheter that can be implemented in its functions when this is required in case of a change in the condition of the patient.

Another object is to provide a catheter with known and available technologies and materials.

Another object is to provide a catheter of low cost.

This aim and these and other objects that will become more apparent hereinafter are achieved by a central venous catheter, characterized in that it comprises a main catheter constituted by a tubular element provided with at least one balloon that is inflatable by a continuously circulating thermal fluid, provided with a central main lumen and two lumens for feeding and recovering said thermal fluid and with at least one seat for the passage of conductors associated with sensors for measuring functional parameters, an auxiliary catheter being also provided hich is adapted to be inserted in the central main lumen, said auxiliary catheter being provided w ith at least one central lumen and with seats for the passage of electrical cables of sensors for functional parameters.

Further characteristics and advantages w i 11 become more apparent from the description of a catheter according to the invention and of implementations thereof, given by way of non-limiting example and illustrated by means of the accompanying drawings, wherein:

Figure 1 is a view of a main catheter according to the invention, shown with the balloon inflated;

Figure 2 is a transverse sectional view of the catheter of Figure 1 , taken along t e line II— II;

Figure 3 is a partial longitudinal sectional view of the main catheter of Figure 1 ;

Figure 4 is a sectional view of the inlet portion of the main catheter of Figure 1 ; Figure 5 is a view of an auxiliary catheter to be used together with the main catheter of Figure 1 ;

Figure 6 is a sectional view, taken along the line VI- VI, of the auxiliary catheter of Figure 5;

Figure 7 is a partially sectional view of the combination of the main catheter of Figure 1 with the auxiliary catheter of Figure 5;

Figure 8 is a view of a variation of the main catheter of Figure 1, where there are a plurality of balloons;

Figure 9 is an enlarged-scale view of the end of the combination of the main catheter and the auxiliary catheter;

Figure 10 is a view of the combination of the main catheter and the auxiliary catheter in the inlet region;

Figure 1 1 is a view of the insertion of the guide wire into a central vein;

Figure 1 2 is a view of the insertion of the main catheter into a vein by means of the guide wire;

Figure 1 3 is a view of the insertion of the auxiliary catheter into the main catheter already inserted in the vein, also showing, by way of example, the expansion of the balloon.

With reference to the cited figures, the central venous catheter according to the invention is composed of a main catheter 1 0 provided by- means of a tubular element 1 1 with which an external membrane 1 2, which when inflated will constitute the balloon for heat exchange, is associated over a preset length.

The tubular element 1 1 , as can be seen better in Figure 2, which is a cross-section thereof, has, in the illustrated case, a central main lumen 13 that is flanked by two lumens, respectively a lumen 14 for feeding the fluid and a lumen 1 5 for the return of the fluid.

Essentially, in the outer wall of the lumen 14 there are a plurality of holes 1 6 which connect the lumen 14 itself with the chamber 1 7, which creates, by means of the external membrane 1 2, the heat exchange balloon.

The thermal fluid introduced into the lumen 14 enters the chamber 1 7, as indicated by the delivery arrow 1 8, and symmetrically the return lumen 1 5 has, in its outer wall, a plurality of return holes 19, through which the fluid introduced into the balloon chamber 1 7 returns to the lumen 15 along the return arrow 20.

In the first part of the main catheter 1 0, the lumen 14 for feeding the fluid separates from the tubular element 1 1 , creating an inlet connector 2 1 which will be connected to a thermal machine, which will cool or heat, depending on the situation, the fluid that is introduced.

Likewise, the return lumen 1 5 in the first part of the tubular element I 1 separates from it, providing a return connector 22 which al so w ill be connected to the thermal machine, which is not shown.

The illustrated structure allows the provision of a closed circuit for circulating the thermal fluid, which in the case of cooling is conveniently NaCl .

With the introduction of the thermal fluid into the balloon chamber 1 7, the chamber inflates, thus determining the shape of the balloon and in practice determining a substantial surface for heat exchange.

The end 23 of the central main lumen 13 protrudes in the same first part of the main catheter 10 as well.

In the front end part, beyond the point where the tubular element 1 1 ends, a front end portion 24 of the tubular element 1 1 that has an open hole 25 for the central main lumen 1 3 protrudes.

The end tip 26 is tapered and soft so as to facilitate the insertion of the catheter 10 in a vein.

At the beginning of the outer membrane 1 2, inside the tubular element 1 1 , there is a first marking 27 provided with a coloring agent that is sensitive to X-rays and likewise a second marking 28, made of the same material that is sensitive to X-rays, is provided in the front part. substantially where the membrane 1 2 ends.

The two markings are used to monitor the placement of the catheter when it is inserted in a vein.

The main lumen 1 3, if the catheter is used in this configuration, is used to introduce, through the hole 25, drugs into a vein when necessary.

The circulation of the fluid, particularly of cold fluid inside the balloon, makes it possible to obtain a hypothermia, i.e., a cooling of the blood, which is very useful in particular therapies, and likewise in other therapies it is possible to introduce and circulate a warm fluid for heating.

Figure 2 shows again two seats, respectively 29 and 30, where the passage of wires of sensors, not shown, can be provided; in the end part 24 of the main catheter 10 they are connected to sensors, for example for monitoring temperature, pressure, glucose etcetera.

Figure 5 shows an auxiliary catheter, generally designated by the reference numeral 3 1 .

The auxiliary catheter 3 1 has an elongated cylindrical tubular shape, with an outside diameter that is slightly smaller than the diameter of the main lumen 1 3 of the main catheter 10.

The auxiliary catheter 3 1 , as shown in Figure 6, has a central lumen 32 which is flanked by two lateral lumens 33 and 34; respectively, said lumens lead out in the front end part in an exit hole 35 for the first lumen, i.e., the lumen 32, and in a lateral exit hole 36 for the lumen 33 and 37 for the lumen 34.

In the inlet part, the central lumen 32 continues with a connector that allows the introduction of liquids or drugs, while the two lumens 33 and 34 also terminate in ends 39 and 40 which also serve for the introduction of liquids or drugs.

In the same auxiliary catheter, as shown in Figure 6, there are again two passage seats, respectively 4 1 and 42, in hich conductors are inserted which are connected to sensors, respectively 43 and 44, that allow detection of the functional parameters of the patient.

In the inlet part, said sensors continue with terminals 45 and 46 that allow connection to monitoring instruments.

The auxiliary catheter 31 has, in its inlet part, a ring 47 which, once the auxiliary catheter 3 1 has been inserted in the main catheter 1 0, abuts against the first part 48 of the main catheter 10, which is threaded so that a ring 49 that is screwed onto the region 48 jointly connects the two catheters, furthermore bringing them to the correct position.

A variation of the main catheter is shown in Figure 8, where it is designated by the reference numeral 50.

In this variation, the balloons are three in number, designated respectively by the reference numerals 5 1 , 52 and 53, consecutive and connected by regions with reduced diameters 54 and 55 which make the main catheter less rigid and therefore make its adaptation easier when it is inside the vein.

For monitoring the placement of the catheter there are, substantially in the inlet part, a series of notches 56 that visualize insertion.

Insertion occurs as shown in Figures 1 1 , 1 2 and 1 3.

First a steel guide ire 58 is inserted in the central vein, designated by the reference numeral 57, and allows, as shown in Figure 12, insertion of the main catheter 1 0 by insertion of the guide wire 58 in the main lumen 13.

When the catheter is in its correct position, if it is not necessary to use the auxiliary catheter, the guide w ire 58 is extracted and the balloon 12 is inflated.

If the auxiliary catheter is needed immediately, or even in a subsequent step, the guide ire 58 is inserted again and is then passed through the lumen 32 of the auxiliary catheter 3 1 , bringing the auxiliary catheter into position.

The catheter according to the invention has practical applications in various pathologies. In particular, by using only the main catheter it is possible to perform thermal treatments for cooling or heating the blood and through the central lumen it is possible, if necessary, to inject drugs.

The balloon is inflated by injection of a cooled or heated fluid into it, so as to obtain the hypothermia of the patient or the heating of the blood, and in this case the fluid is preferably a solution of NaC 1 .

This solution is of the physiological type and therefore even a possible rupture of the balloon will not create problems.

The main catheter is also provided with sensors with which it is possible to monitor first of all blood temperature and also other physiological parameters.

For this reason it is possible to provide main catheters of different types to be used on a case-by-case basis since they are provided with different sensors.

By using the auxiliary catheter it is possible to treat and monitor various pathologies, since this catheter, besides a main lumen that allows the injection of drugs, has two other lumens through which it is possible to introduce into the blood additional drugs or components while the sensors can be of various types for monitoring the physical and functional parameters of the patient.

It is very important that the auxiliary catheter can be replaced w ith auxiliary catheters of another type if the pathology changes and therefore other information from other sensors is needed.

The replacement of the auxiliary catheter does not create any problem for the patient because the main catheter remains in the vein and is not extracted from the body.

With this configuration it is evident how it is possible to adapt and use the most suitable catheter, particularly the auxiliary one, depending on the specific problems.

This also makes catheter management much cheaper, because whereas the main catheter can be substantially always the same, the auxiliary ones are used if and when needed and are selected from a wider range, which is already available.

This allows a considerable optimization and reduction of the management costs for treatment centers.

Of course, what has been described is merely exemplary and may have equiv alent variations, all of which are within the protective scope of the patent; the materials, too, will be selected from those that are known and used in the medical field.

The disclosures in Italian Patent Application No. PD20 1 1 A000 125 from which this application claims priority are incorporated herein by reference.

Where technical features mentioned in any claim are followed by reference signs, those reference signs have been included for the sole purpose of increasing the intelligibility of the claims and accordingly such reference signs do not hav e any limiting effect on the interpretation of each element identified by way of example by such reference signs.

Claims

1. A central venous catheter, characterized in that it comprises a main catheter (10) constituted by a tubular element ( 1 1 ) provided wit at least one balloon ( 12) that is inflatable by a continuously circulating thermal fluid, provided with a central main lumen (13) and two lumens ( 14, 1 5 ) for feeding and recovering said thermal fluid and with at least one seat (29, 30) for the passage of conductors associated with sensors for measuring functional parameters, an auxiliary catheter (3 1 ) being also provided, adapted to be inserted in the central main lumen ( 1 3 ), said auxil iary catheter (3 1 ) being provided with at least one central lumen (32) and with seats (41 , 42 ) for the passage of electrical cables of sensors (43, 44) for functional parameters.

2. The central venous catheter according to claim 1 , characterized in that said auxiliary catheter (3 1 ) is substantially a cylindrical tubular element whose diameter is slightly smaller than the diameter of the central main lumen ( 13 ) of the main catheter ( 1 0) in which it can be inserted.

3. The central venous catheter according to claims 1 and 2, characterized in that said auxiliary catheter (3 1 ) is longer than the main catheter ( 1 0), so that when it is inserted its front end protrudes from the central main lumen ( 13 ).

4. The central venous catheter according to claim 3, characterized in that the exit holes (36, 37) of lumens (33, 34) that are present in the auxiliary catheter (3 1 ) are located in the portion of the auxiliary catheter (3 1 ) that protrudes after the positioning of the central main lumen ( 13 ) of the main catheter ( 10), drugs or fluids for therapeutic use being fed, when necessary, through said holes (36, 37).

5. The central venous catheter according to claim 3, characterized in that in the portion of the auxiliary catheter (3 1 ) that protrudes after the positioning of the main catheter ( 1 0) in the central main lumen ( 1 3 ) there are sensors (43, 44) for monitoring physiological parameters, said sensors being associated with electrical conductors which are inserted in seats (41 , 42) that are present inside the auxiliary catheter (31).

6. The central venous catheter according to claim 1 , characterized in that on said main catheter (10) there are, in regions that are substantially adjacent to the first and last regions of the balloon ( 1 2), two markings (27, 28) prov ided by means of a product that is sensitive to X-rays, so as to allow monitoring of the position of the main catheter when it is located in a vein.

7. The central venous catheter according to claim 1 , characterized in that said lumens ( 14, 1 5 ) end in the first part of the main catheter ( 10) with connectors (2 1 , 22) for connection to a thermal machine for cooling or heating the fluid that circulates in the balloon ( 1 2), said fluid being preferably NaCl.

8. The central venous catheter according to claims 1 and 7, characterized in that in a constructive variation the main catheter has a plurality of consecutiv e balloons blended with regions having a smaller diameter, which is only slightly larger than the tubular element ( 1 1 ) so as to maintain hydraulic continuity but allow greater flexibility of the assembly.

9. The central v enous catheter according to claim 1 , characterized in that said auxiliary catheter (31), once it has been inserted in the central main lumen ( 1 3 ) of the main catheter ( 10), is locked by a ring (49), which is screwed onto the first threaded part (48) of the tubular element ( 1 1 ) of the main catheter ( 10), compressing a ring (47) which is integral with the auxiliary catheter (3 1 ).