WO2022146366A1

WO2022146366A1 - A double lumen, multiple-outflow, multiple-inflow veno venous ecmo (extracorporeal membrane oxygenation) cannula

Info

Publication number: WO2022146366A1
Application number: PCT/TR2021/051512
Authority: WO
Inventors: Yahya YILDIZ
Original assignee: Istanbul Medipol Universitesi Teknoloji Transfer Ofisi Anonim Sirketi
Priority date: 2020-12-31
Filing date: 2021-12-26
Publication date: 2022-07-07
Also published as: TR202022783A1

Abstract

The present invention relates to a venovenous ECMO (Extracorporeal Membrane Oxygenation) cannula with multiple inflows, double lumen and multiple outflows at two different levels.

Description

A DOUBLE LUMEN, MULTIPLE-OUTFLOW, MULTIPLE-INFLOW VENO VENOUS ECMO (EXTRACORPOREAL MEMBRANE OXYGENATION) CANNULA

TECHNICAL FIELD

The present invention relates to a venovenous ECMO (Extracorporeal Membrane Oxygenation) cannula with double lumen, multiple inflows, and multiple outflows at two different levels.

PRIOR ART

Extracorporeal membrane oxygenation (ECMO), being one of the extracorporeal life support systems, may be used as an artificial heart and/or artificial lungs. Extracorporeal membrane oxygenation (ECMO) is an extracorporeal life support method employed in patients of all age groups who suffer from heart, circulatory, and/or respiratory failure and do not respond to conventional treatment methods. The ECMO system incorporates drawing venous (outflow) blood from a patient's body by using cannula or cannulae and infusing arterial (inflow) blood back into the patient's body after venous blood is subjected to gas exchange and oxygenation.

Particularly, the cannulae used for venovenous ECMO in pediatric and adult age groups may suffer performance issues stemming from the insufficiency of blood drawing and blood infusing capacities. Overcoming this issue requires using larger cannulae according to patients' sizes. While insertion problems are experienced accordingly, the administration imposes a risk of causing further injury in a patient's heart, vessels and organs in close proximity.

Moreover, an echocardiography device is utilized with the aim of confirming that the cannula, which is inserted with difficulty, is indeed properly positioned, and the use of this device requires distinct experience. Furthermore, even in cases where proper positioning is achieved with cannula, the smallest movement of the patient may cause the cannula to become dislocated from the desired position, which in turn requires repositioning. Additionally, extended remain of cannulae in patients brings along a risk for catheter infection.

In the state of the art, ECMO cannulae may generally be placed through venovenous (vv), venoarterial (va), or venovenoarterial (vva) routes, or placement thereof may be performed in various ways and types apart from those named above. The administration of ECMO cannulae may be peripheral or central.

Peripheral ECMO may be performed via the cannulation of Internal Jugular Vein (IJV) and Femoral Vein/artery and arteries. Peripheral vv ECMO may be carried out through the cannulation of IJV and Femoral Vein. Peripheral va/vva ECMO may be performed via the cannulation of IJV and Femoral Vein/ Artery.

As the peripheral vv ECMO may be performed through two vessels, namely, two veins by using two cannulae, it may also be carried out by means of a single cannula with double lumen through the IJV. Central ECMO, on the other hand, is an ECMO application performed through the right atrium of the heart, and the aorta.

The US patent document numbered US2005085761 available in the state of the art discloses an expandable double lumen cannula for vv ECMO. Said patent document describes a system, and method for the use of a simpler, less invasive, self-expandable percutaneous double lumen cannula assembly for vv ECMO. The said invention achieves theoretical total venous blood drainage, total extracorporeal gas exchange, and eliminates the need for recirculation and multiple cannulations. Thus, vv ECMO is simplified, surgical and blood trauma is decreased, and the application range thereof is expanded. An embodiment of the cannula disclosed in the same document comprises three orifices. The double lumen cannula of the invention further comprises a radio-opaque marker. The cannula disclosed in the invention document has a rigid structure and comprises an adjustable flow mechanism. However, since the subject design does not encompass a design spectrum that is capable of accommodating different size and anatomic structure changes varying based on the development of a patient, the performance of the cannula may be ambiguous or less than ideal. In the same design, since the upper drawing opening and the infusion opening are too close to one another, arterial blood may pass through venous blood drainage holes inside the system, thereby causing recirculation. This, in turn, may result in a decrease in the total amount of oxygenated blood. Moreover, the subject design does not comprise a fastening element, i.e., a cannula retaining clamp that enables fastening the cannula to various parts of the skin, which in turn, brings along the risk of displacement of the cannula anchored to the skin merely by suture, and due to loss of patient blood rapidly. The invention disclosed in the same US patent document numbered US2005085761 does not comprise a structural component, which ensures that the inner lumen remains stable in case of twisting and wrenching. In the same design, the section of the cannula has a circular shape and the structure that separates drawing and infusion canals is flexible. In this design, the variation of lumen diameters based on drawing and infusion power may pose a risk for the stabilization of the flow. The subject cannula design does not comprise a special structural component that provides resistance against potential infections. The subject design comprises only one indicator, i.e., the radio-opaque marker that shows the intracardiac and intravenous position of the cannula. Even though this marker shows the level of the cannula, it is not enough to show the direction of the orifice.

The US patent application numbered US9233223 is another document available in the prior art. This document discloses a coaxial venal cannula. The dual lumen cannula disclosed in this patent document is composed of a proximal end and a distal end, and these ends comprise two lumens nested together. Moreover, in said cannula, a first tube reaches to an end with a proximal orifice comprising a plurality of holes. There is a second tube that is coaxial with the first tube and extends fixedly along its mid-portion, and a distal end comprising a drainage hole where the second tube reaches to an end. In the cannula disclosed in this patent document, the positioning of lumens is coaxial, and the circular shape of the cannula limits the amount of drawn and infused blood.

The orifices provided on the same cannula have a multi-hole structure and each orifice is configured to serve both drawing and infusing functions depending on the position of administration so that the cannula may be adapted to both neck and leg applications. However, since this cannula does not take into consideration the fact that drawing and infusing forces in the cannula are reverse forces, it has the potential risk of inducing hemolysis by causing damage to blood cells during the procedure.

Since apertures are positioned only on two levels in the cannula, it is uncertain that proper and sufficient blood draw and infusion is provided, furthermore, it appears to be inevitable that the said structure will be insufficient in diverting the collected venous blood coming from the upper and lower body in the circulatory system to a valve located at a level at a middle portion thereof. Again, an increased amount of short circuit, namely, recirculation is inevitable in this design, which in turn, corresponds to an underperforming cannula. Moreover, the cannula is provided with an increased length so that it may be used in applications performed in the leg region. This renders the use of the cannula impractical in patients with short height. In the cannula, of which placement into pulmonary artery is additionally proposed with the notion of providing a more effective use, the mentioned placement method is exceedingly invasive (posing high risk of damage to vessels and similar tissues) with limited and ambiguous benefits. Moreover, this particular mode of application increases costs even further, as it requires distinct experience and customized equipment (angiography laboratory, advanced echocardiographic imaging, etc ). Additionally, this mode of application negatively affects the proper blood loading, discharge and contraction of the heart because an excessively long cannula is present inside the heart. The same design also lacks a fixing element. Therefore, the maintenance of cannula's position is under constant risk. This cannula design further lacks an indicator, marker component that shows the position of the cannula, therefore a special imaging experience (scope, angiography, echocardiogram/ultrasound) is required in order to ensure that the cannula is positioned properly.

The disadvantages disclosed above limits the use of ECMO in patients who are in need, reduces the application of and benefits gained from ECMO treatment, thereby prolonging the duration of hospital stay or the duration of disease, increasing patient mortality, and consequently, causes increase in health care costs.

Considering both the state of the art and the clinical experiences of attending physicians working in this field, it is observed that there is a necessity towards a novel double lumen ECMO cannula that comprises diverting blood transfusion orifices and that is capable of overcoming disadvantages, which are present in cannula designs, details of which are provided above, and which affects the safety of patients including recirculation, infection, and difficulty in positioning cannulae available in the state of the art.

BRIEF DESCRIPTION OF THE INVENTION

The present invention, with the aim of overcoming the disadvantages disclosed above and introducing further advantages into the relevant technical field, relates to a novel venovenous ECMO (Extracorporeal Membrane Oxygenation) cannula (A) with multiple inflows, double lumen, and multiple outflows.

DESCRIPTION OF THE FIGURES

Figure 1 illustrates the front view of the double lumen, multiple-outflow, multiple-inflow venovenous ECMO cannula according to the present invention.

Figure 2 illustrates the comparison of wall shear stress (WSS) distributions of double lumen Avalon (A) and Origen (B) ECMO cannulae used in the known state of the art. It is observed that higher wall shear stress is generated towards the tricuspid valve at the exit of the proximal inflow end.

Description of reference numerals used in said figures is provided below.

1 : Distal outflow end

2: Distal inflow end

3 : Right subclavian vein drawing hole

4: Internal jugular vein drawing hole

5 : Innominate vein drawing hole

6: Inflow-diverting holes

7: Horizontally-beveled proximal inflow end

8: Proximal outflow end

9: Serrated structure

10: Outer radio-opaque indicator

11 : Laterally -beveled proximal end indicator

12: Main inflow orifice

TV: Tricuspid valve

IVC: Inferior vena cava

SVC: Superior vena cava

DETAILED DESCRIPTION OF THE INVENTION

The present invention relates to a double lumen, multiple-inflow, multiple-outflow venovenous ECMO (Extracorporeal Membrane Oxygenation) cannula (A).

The double lumen ECMO cannula (A) according to the present invention comprises; a distal outflow end (1), a distal inflow end (2), a right subclavian vein drawing hole (3), an internal jugular vein drawing hole (4), an innominate vein drawing hole (5), a plurality of inflow-diverting holes (6), a horizontally-beveled proximal inflow end (7), a proximal outflow end (8), a serrated structure (9), an outer radio-opaque indicator (10), and a laterally-beveled proximal end indicator (11). The double lumen ECMO cannula (A) according to the present invention may comprise 2-4 inflowdiverting holes (6).

The double lumen, multiple-inflow, multiple-outflow venovenous ECMO cannula (A) according to the present invention facilitates the use of venovenous ECMO in patients of neonatal and pediatric age groups, thereby reducing the mortality rates in these age groups. Furthermore, proper cannula placement is facilitated, and the ideal placement location may be determined without the need for distinct experience.

The double lumen, multiple-inflow, multiple-outflow venovenous ECMO cannula (A) may optionally comprise a cannula fastening apparatus, for instance, a movable ladle-shaped handle with lugs. The cannulae placed in such a way are prevented from becoming dislocated due to position changes of a patient’s body.

The double lumen, multiple-inflow, multiple-outflow venovenous ECMO cannula (A) may optionally be coated with a coating material that comprises silver, colloidal silver, or silver nanoparticles and/or that is known to have antibacterial features or may be coated with a gel saturated with chlorhexidine. The outer surface coating of the cannula may be provided with antimicrobial characteristics by means of coating with a nanotechnology material charged with negative ions. Thus, the potential risk of infection induced by the prolonged stay of the cannula in the patient's body is reduced.

The double lumen, multiple-inflow, multiple-outflow venovenous ECMO cannula (A) according to the present invention is made of a material that reduces the risk of causing injury to vascular and cardiac structures, that is fine, soft, and flexible, yet resistant to factors such as breaking and twisting, which cause the inner lumen to become constricted.

The ellipsoid-shaped section of the horizontally-beveled proximal inflow end (7) provided on the double lumen, multiple-inflow, multiple-outflow venovenous ECMO cannula (A) according to the present invention increases the amount of the drawn blood with less suction pressure.

The horizontally-beveled proximal inflow end (7) provided on the double lumen, multiple-inflow, multiple-outflow venovenous ECMO cannula (A) has a broad orifice gap and enables diverting the blood flow to the cardiac valve, and therefore to the right ventricle by means of the horizontally- beveled shape thereof.

The laterally-beveled proximal end indicator (11) and the outer radio-opaque indicator (10) provided on the double lumen, multiple-inflow, multiple-outflow venovenous ECMO cannula (A) according to the present invention enable determining the position of the horizontally-beveled proximal inflow end (7) accurately and correctly.

The double lumen, multiple-inflow, multiple-outflow venovenous ECMO cannula (A) according to the present invention comprises a total of four indicators, two of which are provided on the proximal inflow end (8), one (11) provided on the horizontally-beveled proximal inflow end (7) so as to either have a C shape or oval-ellipsoid shape at front and rear, and finally, one (10) located at the bottom portion, so that the ideal position of the cannula according to the present invention may be determined and affirmed at a desired frequency.

The double lumen, multiple-inflow, multiple-outflow venovenous ECMO cannula (A) according to the present invention is suitable for jugular application, i.e., application through the neck owing to the right subclavian vein drawing hole (3), internal jugular vein drawing hole (4), and the innominate vein drawing hole (5) provided on the cannula.

The fact that the proximal inflow end (7) of the cannula according to the present invention has a horizontally-beveled shape and that flow-diverting holes (6) are provided on the body of the cannula enables reducing blood diverting and the trauma thereof stemming from the use of the ECMO cannula and allows expanding the range of application. Moreover, since the blood flow is diverted to the tricuspid valve by means of the cannula according to the present invention, the incidence of recirculation (short circuit) present in ECMO cannulae available in the state of the art is reduced or eliminated completely.

In the applications carried out by using other double lumen cannulae available in the state of the art, the inventors have determined that diverting blood into the tricuspid valve through a single inflow hole results in a high rate of blood flow to the tricuspid valve and to the right ventricle, thereby inducing insufficiency at the valve (Figure 2). The double lumen, multiple-inflow, multiple-outflow venovenous ECMO cannula (A) according to the present invention is believed to reduce such undesirable effects caused by other double lumen cannulae available in the state of the art. The serrated structure (9) provided in the ECMO cannula (A) according to the present invention is composed of serrations. These serrations (9) are positioned towards the distal end of the body of the cannula. In other words, serrations located on the serrated structure (9) provided on the cannula (A) according to the present invention are positioned on the body of the cannula such that they form an angle in a range between 1° and 175° relative to the body of the cannula.

The aim of the serrated structure (9) provided on the cannula (A) according to the present invention is to create a barrier against percutaneous entry of bacteria and microorganisms.

The cannulae according to the present invention may be manufactured from metallic or polymeric materials available in the state of the art such as chlorhexidine, potassium iodide, alcohol, etc., that are not affected by disinfectants, that are inert to these disinfectants, and that do not interact with these disinfectants.

The cannula (A) according to the present invention may be manufactured in various types and sizes, and for every age, height, and weight so as to accommodate the characteristics of human anatomy of different sizes, for example, neonatal, pediatric, and adult patients.

The term "comprising" used within the scope of this description is intended to mean "including".

Embodiments of the present invention may be combined where appropriate in the technique.

The embodiments are disclosed herein so as to comprise specific features/elements. Other embodiments that comprise the features/elements described herein, or that are composed of said features/elements are also included in the scope of the description provided herein.

Claims

CLAIMS A double lumen, multiple-inflow, multiple outflow venovenous ECMO (Extracorporeal Membrane Oxygenation) cannula (A), characterized in that it comprises; a distal inflow end (1), a distal outflow end (2), a right subclavian vein drawing hole (3), an internal vein drawing hole (4), an innominate vein drawing hole (5), a plurality of inflow-diverting holes (6), a horizontally-beveled proximal inflow end (7), a proximal outflow end (8), a serrated structure (9), an outer radio-opaque indicator (10), and a laterally-beveled proximal end indicator (11). A cannula (A) according to Claim 1, characterized in that it comprises 2-4 inflowdiverting holes (6). A cannula (A) according to any one of Claim 1 or 2, characterized in that it comprises a clampe-shaped component with lugs in order to prevent the cannula from becoming dislocated due to position changes of a patient’s body. A cannula (A) according to any one of Claim 1 to 3, characterized in that it is coated with a coating material that comprises silver, colloidal silver or silver nanoparticles and/or that is known to have antibacterial features. A cannula (A) according any one of Claim 1 to 4, characterized in that it comprises a total of four indicators, two of which are provided on the proximal outflow end (8), one (11) provided on the horizontally-beveled proximal inflow end (7) so as to either have a C shape or oval-ellipsoid shape at front and rear, and one (10) located at the bottom portion. A cannula (A) according to any one of Claim 1 to 5, characterized in that the serrated structure (9) is composed of serrations and said serrations are positioned towards the distal end of the body of the cannula.

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