Patent Description:
This invention relates to devices for accessing the interior of a subject, such as the vascular system, through extracorporeal life support (ECLS) system components, such as extracorporeal membrane oxygenation ("ECMO") circuits. More in particular, it relates to cannulas, adaptors, sheaths, tubing, connectors and other medical devices for use as or in connection with bypass system components to gain entry to the vascular system through the bypass system, such as an ECMO circuit.

<CIT> discloses a catheter assembly that includes a catheter adapter having a port disposed on tis sidewall and a valve coupled to the port to seal the opening in the port. <CIT> discloses a first catheter with a first catheter body providing a longitudinal bore and a flexible first seal at its distal portion. The first seal can at least partially occlude the bore at the distal portion of the catheter body in a first configuration. A second catheter can be slid into or through the bore of the first catheter body, such as to expand the first seal into a second configuration.

Extracorporeal membrane oxygenation ("ECMO") is a form of cardio-pulmonary bypass that is employed to support critically ill patients with acute cardiac failure, respiratory failure, or combined cardiopulmonary failure. A typical ECMO circuit <NUM> as shown in <FIG> consists of multiple components including cannulas, tubing, an oxygenator, and pump with a controller. A heater-cooler element may be added for temperature management as well. Generally, a venous cannula <NUM> is inserted either into a large vein, such as a femoral vein, or the right atrium of the heart for drainage of blood from the patient. The blood is carried via bypass tubing 3a to a pump (not shown), which provides forward flow through the circuit, and to an oxygenator (not shown), which both oxygenates the blood and allows removal of carbon dioxide. The blood is then returned to the patient via bypass tubing 3b connected to a return or arterial cannula <NUM>, which is generally placed in either the aorta or a large peripheral vessel, such as the femoral artery. Depending on the configuration, an ECMO circuit can provide gas exchange for patients with acute pulmonary failure, or both gas exchange and hemodynamic support for patients with acute cardiac or combined cardiopulmonary failure. In the setting of acute cardiac and pulmonary failure, ECMO can provide immediate restoration of perfusion and oxygen delivery to tissues, thereby preventing worsening acidosis, shock, multisystem organ failure and ultimately death and allowing for time for either organ recovery or diagnosis and intervention.

Use of this form of temporary mechanical circulatory support was initially reported in <NUM>. Since its introduction, technological advances in all components of the ECMO circuit have occurred. For example, improved cannula design has allowed more facile insertion with less trauma to blood vessels. Advances in pump and oxygenator design have allowed for greater efficiency and less trauma to blood elements. In the context of these advances, it was discovered that ECMO could serve as a valuable tool in supporting critically ill patients afflicted with H1N1 influenza. In its most severe manifestations, H1N1 was associated with a high mortality rate and it was found that ECMO could reduce mortality in these critically ill patients. Improvements in ECMO technology, along with its demonstrated success with critically ill H1N1 patients, have led to a dramatic growth in the use of ECMO for patients with acute cardiopulmonary failure.

ECMO is generally considered to be a supportive technology intended to provide oxygen and hemodynamic support to patients with acute cardio-pulmonary failure through a closed system. Many patients that require ECMO also require invasive procedures for diagnosis and potentially intervention. Many of these procedures, such as left and right heart catheterization, percutaneous coronary intervention, or insertion of catheters for instillation of thrombolytics, require access to the cardiovascular system, which is usually established by inserting an introducer sheath into a peripheral vessel after obtaining access with a needle. However, institution of ECMO generally requires thorough systemic anticoagulation to increase blood flow and prevent clotting. Anticoagulation, however, complicates obtaining access to the vascular system for other subsequent diagnostic and therapeutic procedures, as the anticoagulants cause an increased risk of bleeding when attempting to access a vessel. Furthermore, vascular access is often obtained in the clinical setting by palpating a patient's pulse as a landmark for locating the blood vessel. ECMO provides laminar flow and a patient on ECMO may have very little or no difference in systolic or diastolic blood pressure, resulting in a very low pulse pressure. While a patient may have adequate blood pressure, there may be very little pulsatility and it may be difficult or impossible to palpate a pulse while on ECMO. Thus, despite the potential necessity for vascular access for subsequent diagnostic and therapeutic procedures while on ECMO, obtaining vascular access in patients on ECMO may be challenging and result in complications including vascular injury and bleeding.

Since establishment of an ECMO circuit requires insertion of cannulas into the vascular system, the ECMO circuit itself has the potential to serve as an access point to the cardiovascular system and allow the performance of diagnostic and therapeutic procedures to promote the recovery of the patient. Utilizing the ECMO circuit itself for access to the cardiovascular system would circumvent the challenges and risks associated with attempting to access another blood vessel. However, an ECMO circuit is generally not used as a vascular access point in clinical practice as a safe and facile means of doing so does not exist with currently available technology.

For example, the arterial or in-flow cannula <NUM> generally represents the most proximate component of the ECMO circuit to the patient's cardiovascular system. This arterial cannula <NUM> is typically inserted into a large peripheral vessel, such as the femoral or axillary artery, or directly into the aorta. Most commercially produced cannulas have a small, perpendicular side port <NUM> with a Luer connector, as shown in <FIG>. This side port <NUM> allows air to be eliminated from the circuit and also allows for establishment of a secondary circuit, such as for perfusion of blood to the ipsilateral limb. Such secondary circuits are established by a secondary circuit connector <NUM> attaching to the side port <NUM> of the arterial cannula. Secondary circuit tubing <NUM> directs blood from the side port <NUM> to a superficial cannula <NUM>, such as a superficial femoral arterial cannula. Both the main arterial cannula <NUM> and the superficial cannula <NUM> may be introduced into the artery at the same insertion point <NUM>, with the cannula <NUM> being directed toward the heart, and the superficial cannula <NUM> being directed toward the ipsilateral limb, such as the leg in a femoral arterial setting. The secondary circuit therefore allows perfusion into the ipsilateral leg and prevents ischemia and tissue damage in the leg.

Many patients on ECMO systems will typically require diagnostics and therapeutic interventions, which are commonly facilitated by the placement of an introducer sheath <NUM>, shown in <FIG>, in the patient's artery. The introducer sheath <NUM> may also include a hub <NUM> with side arm 16a for venting air out of the system through venting tubing <NUM> by operation of a valve <NUM>. The side port <NUM> of an ECMO arterial cannula <NUM> represents a potential access point to the ECMO circuit for vascular access. However, current vascular introducer sheaths <NUM> have no mechanism of interfacing with the side port <NUM>. As is evident from <FIG>, arterial sheaths <NUM> are too long and incompatible with the short right angle side port <NUM> provided in a cannula <NUM>. They therefore offer no mechanism to negotiate the right angle presented by the side port <NUM>, and no mechanism to direct a diagnostic or interventional wire or catheter in the appropriate direction (toward the patient rather than toward the ECMO pump) once inserted. Because insertion is not possible, introducer sheaths <NUM> provide no mechanism for establishing a hemostatic seal to the cannula <NUM>, which would be needed for safe insertion of a wire or catheter. Attempts to insert a standard arterial sheath <NUM> into the side port <NUM> of a cannula <NUM> would result in uncontrolled bleeding around the sheath <NUM>, inability to maintain the sheath <NUM> in appropriate position, kinking of the sheath <NUM>, misdirection of intervention devices such as wires or catheters, and inability to pass wires or catheters altogether. For these reasons, currently available arterial sheaths are not amenable for insertion directly into a cannula.

The present invention provides an adaptor with the features recited in claim <NUM> and a system for vascular access with the features recited in claim <NUM>.

The present invention is directed to adaptors to permit the cannulas of an ECLS system, such as an ECMO circuit, to be used as an access point to gain endovascular entry. The adaptors provide the ability to interchangeably utilize the side port of a cannula not only for introduction of intervention devices, such as wires or catheters, into the cardiovascular system, but also for other purposes as well, such as establishing a secondary circuit for distal perfusion. Full occlusion of the side port is also made possible when the side port is not in use, to prevent blood stagnation and thrombus formation.

Specifically, the present invention is directed to a variety of adaptors that enable the use of an ECMO circuit as a vascular access point, and systems for vascular access that include such adaptors. These adaptors can interface with a standard cannulas currently used in ECLS systems, such as ECMO circuits, and provide an access point for intervention devices such as wires or catheters into the system. The adaptors of the present invention include curved or straight shafts having an angle that can negotiate the right angle of a standard cannula side port and provide directionality to a wire or catheter inserted therein. A hemostatic membrane allows for insertion of the intervention device without back bleeding.

The adaptors and systems including the same, together with their particular features and advantages, will become more apparent from the following detailed description and with reference to the appended drawings.

Like reference numerals refer to like parts throughout the several views of the drawings.

As shown in the accompanying drawings, the present invention is directed to adaptors and systems comprising these adaptors that enable the use of an ECLS circuit, such as ECMO, as a vascular access point. The adaptors and systems enable not only vascular access for an intervention device, such as a wire, catheter or the like, but also provide full occlusion of the side port of the ECMO cannula when not in use.

Although described here in the context of an ECMO system, it should be understood that adaptors and systems of the present invention may be used with any appropriate cannulation or ECLS system, and is not limited to vascular applications. In addition, the devices and systems described herein can be used with bypass systems, such as a cardiopulmonary bypass circuit, for temporary support such as during an open heart operation. The inventions described herein may be more preferably used with longer term support circuits, such as those in use over <NUM> hours or more. In addition, the terms "subject" and "patient" may be used interchangeably and refer to the individual who is on bypass in which intracorporeal access is desired.

As seen in <FIG>, one aspect of the invention includes a variety of adaptors <NUM> designed for use with standard ECMO arterial cannulas <NUM> having a right angle side port <NUM> as an access point. These adaptors <NUM> can successfully navigate or circumvent the <NUM>° turn of the side port <NUM> of an arterial or in-flow cannula <NUM> without kinking or damage. They therefore permit access to the cannula lumen <NUM>, without obstructing the lumen, for access to the vascular system through the cannula <NUM>. Accordingly, the adaptor <NUM> may be used instead of an introducer sheath <NUM> to access the vascular system, and enables access to the vascular system through the ECMO circuit without further percutaneous action.

As depicted in <FIG>, the adaptor <NUM> includes a body <NUM> that acts as a hub for the remaining components of the adaptor <NUM>, and may be manipulated by an operator or user during insertion. The body <NUM> is preferably made of a medical-grade plastic or other suitable material for medical use, and may be rigid. In some embodiments, the body <NUM> may include a side arm <NUM> that can be used for venting and otherwise removing air from the system, described in greater detail below.

The adaptor <NUM> also includes a shaft <NUM> that extends from one end of the body <NUM>. In at least one embodiment, the shaft <NUM> may extend at least partially into the body <NUM> on one end, and extends away from the body <NUM> on the opposite end. The shaft <NUM> may include an elongate structure dimensioned to be inserted and pass through the side port <NUM> of a cannula <NUM>, as shown in <FIG>. For instance, the shaft <NUM> may have a circular or tubular configuration, and a diameter that corresponds to, or is smaller than, the inner diameter of the side port <NUM>. Accordingly, the shaft <NUM> may fit inside the side port <NUM>, and may provide a snug fit in some embodiments. The shaft <NUM> is at least as long as the side port <NUM> of a cannula <NUM>, and may extend into the cannula lumen <NUM>. In some embodiments, the shaft <NUM> may extend to the wall of the cannula <NUM>, but in at least one preferred embodiment the shaft <NUM> does not extend to the wall of the cannula <NUM>. Regardless of the embodiment, however, the shaft <NUM> of the present adaptor <NUM> is shorter in length than that of a standard introducer sheath <NUM>. The shorter length of the sheath <NUM> facilitates the navigation of the right angle side port <NUM> (discussed below) and prevents kinking of the shaft <NUM> when inserted into the side port <NUM>.

The shaft <NUM> may be made of a semi-flexible plastic material, such as fluorinated ethylene polypropylene or polyethet block amide plastics used in endovascular and other intervention systems, or other suitable medical-grade plastics and materials. Such a semi-flexible material provides sufficient rigidity to maintain its shape for directional guiding of a wire or catheter, but is flexible enough to bend or flex slightly as needed during the insertion process and to prevent damage to the shaft <NUM> upon the introduction of a medical device therein. The body <NUM> of the adaptor <NUM> may be made of a similar semi-flexible material as the shaft <NUM>, or may be made of more rigid material than the shaft <NUM>.

The shaft <NUM> may have a variety of configurations that enables modifying an angle of insertion of an intervention device, such as a wire or catheter, inserted into the adaptor <NUM> and directs the intervention device into the cannula lumen <NUM>. For example, in at least one embodiment as depicted in <FIG>, the shaft 33a is curved. The curved shape of the shaft 33a provides directionality to a medical device introduced therein, such as a wire or catheter. When positioned correctly, the curved shaft 33a reliably directs the wire or catheter introduced therein toward the patient's heart, rather than back in the direction of the ECMO system. The curved shaft 33a is long enough to extend into the cannula lumen <NUM> when inserted, but is also short enough in length to easily navigate the right angle of the side port <NUM> during insertion, as depicted through <FIG>. In <FIG>, an adaptor 30a having a curved shaft 33a is provided. To gain access to the cannula lumen <NUM>, the distal opening of the curved shaft 33a is aligned with the opening of the side port <NUM>, as shown in <FIG>. The distal end of the curved shaft 33a is inserted into the side port <NUM> of the cannula <NUM>, and the adaptor 30a is rotated along the directional arrow shown in <FIG> until the curved shaft 33a is passed through the side port <NUM> and extends into the cannula lumen <NUM>, as in <FIG>. Alignment of the curved shaft 33a and rotation of the adaptor 30a for insertion of the curved shaft 33a are performed so as to direct the opening of the curved shaft 33a toward the heart of the patient once fully inserted in the cannula <NUM>, as depicted throughout <FIG>. The relatively short length of the curved shaft 33a, being slightly longer than the length of the side port <NUM>, combined with the curvature of the shaft 33a, allows it to be rotated around the right angle of the side port <NUM> during insertion. It also prevents the shaft 33a from kinking at the inner wall of the cannula lumen <NUM>, since in at least one embodiment the curved shaft 33a is not long enough to reach the opposite wall of the cannula lumen <NUM> during insertion. In some embodiments, the curved shaft 33a may be long enough to reach the opposite wall of the cannula lumen <NUM> during insertion, but in these embodiments the semi-flexible material of the curved shaft 33a allows it to flex and deflect off of the cannula wall, and resiliently keep its curved shape. Once the adaptor 30a is in place, as in <FIG>, a connector <NUM> can be tightened to selectively and releasable secure the adaptor 30a to the cannula <NUM>, thereby securing the adaptor in place and preventing bleeding around it.

In other embodiments, as in <FIG>, the shaft 33b has a straight configuration and extends substantially linearly from the body <NUM> of the adaptor 30b. In such embodiments, the distal end of the shaft 33b opposite of the body <NUM> includes a deflector <NUM> that protrudes or extends from an interior wall of the shaft 33b at an angle, thereby creating an angled surface upon which a wire, catheter or other medical device inserted through the adaptor 30b may be deflected in a gentle curve to direct it into the cannula lumen <NUM>. Accordingly, the deflector <NUM> changes the angle of the intervention device <NUM> from the initial angle of insertion to a different angle that directs the intervention device <NUM> into the cannula lumen <NUM>. The deflector <NUM> may be made of the same semi-flexible material as the rest of the shaft 33b, as discussed previously, or may be made of a slightly more rigid material that resists flexing when pressure is applied, so as to direct an intervention device <NUM>, such as a wire or catheter, appropriately and not lose its shape. As used herein, an intervention device <NUM> may be any diagnostic and therapeutic device used in medical procedures, and is not limited to wires or catheters. In some embodiments, the deflector <NUM> is made of a hard medical-grade plastic, such as polycarbonate or nylon, although other suitably rigid materials are also contemplated. In further embodiments, the entire shaft 33b,c and deflector <NUM> may be made of a hard plastic, polycbarbonate or nylon, or other rigid material. In some embodiments, as in <FIG>, the deflector <NUM> may be at the terminal end <NUM> of a straight shaft 33b, such that the shaft 33b has an angled end.

In other embodiments, as in <FIG>, the straight shaft 33c may include a deflector <NUM> as before, but has a flat or straight terminal end <NUM> outer end. In these embodiments having a straight shaft 33b,c and a deflector <NUM>, the shaft 33b,c may have an opening <NUM> at the side at the terminal end <NUM>. Accordingly, the opening <NUM> is facing or pointed in the direction of the patient's heart, so as to appropriately direct a wire or catheter exiting from the shaft 33b,c. Additionally, the straight shaft 33b,c is longer in length than the side port <NUM>, but is shorter than the distance to the opposite wall of the cannula <NUM>. Accordingly, the right angle side port <NUM> does not pose a navigational risk in these straight shaft 33b,c embodiments, since the straight shaft 33b,c easily conforms to the straight channel <NUM> of the side port <NUM>, and the internal deflector <NUM> creates the required angular change to direct an inserted wire or catheter toward the patient's heart.

Regardless of the particular configuration, the shaft <NUM> provides access for an intervention device <NUM> to the cannula lumen <NUM>, and modifies the angle of insertion of the intervention device <NUM> and directs the intervention device <NUM> into the cannula lumen <NUM>. Specifically, as seen in <FIG>, <FIG>, the cannula lumen <NUM> has an axial flow path <NUM> of fluid (such as blood from an ECMO system) being directed through it. The shaft <NUM> of the adaptor <NUM> changes the direction of the intervention device <NUM> upon insertion and directs it not only into the cannula lumen <NUM>, but specifically in the direction of, or consistent with, the axial flow path <NUM> of the cannula lumen <NUM>. In at least one embodiment, this is toward the patient's heart, for cardiopulmonary intervention.

The shaft <NUM>, and with reference to <FIG>, <FIG>, may include a flange <NUM> that has a wider diameter than the remainder of the shaft <NUM>. For example, the flange <NUM> may be circumferentially disposed around the shaft <NUM> and extend radially away from the shaft <NUM>. The flange <NUM> is dimensioned to correspond with and abut a terminal lip <NUM> at the outermost edge of the side port <NUM> when the adaptor <NUM> is fitted on the side port <NUM>. In this manner, the flange <NUM> may limit how far the shaft <NUM> may enter the side port <NUM> and cannula lumen <NUM>.

The adaptor <NUM> may further include a connector <NUM>, as shown in <FIG>, <FIG>. The connector <NUM> is a fitting that removably secures the adaptor <NUM> to the side port <NUM> of the cannula <NUM>. The connector <NUM> may be any suitable fitting for selectively releasable connection, such as a snap fitting, or a Luer connector that connects by screw action through a series of threads on the inside of the connector <NUM>. These threads may interact with the lip <NUM> of the side port <NUM>, such that as the connector <NUM> is turned or rotated about the side port <NUM>, the lip <NUM> engages and is moved through the threads of the connector <NUM>. In at least one embodiment, the connector <NUM> is a floating Luer connector that rotates independently of the remainder of the adaptor <NUM>, such as the shaft <NUM>. Such floating connector <NUM> may be preferable in embodiments where maintaining the direction or alignment of the opening <NUM> of the shaft <NUM> within the cannula lumen <NUM> is important, as in <FIG>. In other embodiments, as when the orientation or direction of the shaft <NUM> is not critical after insertion, as in <FIG> and <FIG>, the connector <NUM> may be secured to and/or rotate with the adaptor <NUM> or shaft <NUM>. In such embodiments, the connector <NUM> may be integrated into the adaptor <NUM>, such as in the body <NUM> of the adaptor <NUM>.

In at least one embodiment, the flange <NUM> of the shaft <NUM> may act as a washer between the connector <NUM> and the lip <NUM> of the side port <NUM>, forming a seal when the connector <NUM> is tightened down onto the side port <NUM>. Further, in some embodiments, the body <NUM> may include a cavity <NUM> on the underside which is correspondingly shaped to the connector <NUM>, such that at least a portion of the connector <NUM> may be inserted into the cavity <NUM> of the body <NUM>, as seen in <FIG> for example.

The adaptor <NUM> also includes an adaptor lumen <NUM> extending through and connecting the interior of the body <NUM> and shaft <NUM>, shown in <FIG>, <FIG>. The adaptor lumen <NUM> provides a hollow interior through which an intervention device <NUM> such as a wire or catheter may be introduced. The adaptor lumen <NUM> may be a single lumen, or may be separate lumens of the body <NUM> and the shaft <NUM> that are continuous with one another. Accordingly, in some embodiments, the adaptor lumen 31a is curved through a curved shaft 33a, as in <FIG>. In other embodiments, the adaptor lumen 31b,c is straight through a majority of its length, and is angled at the distal end of the shaft 33b,c.

The adaptor lumen <NUM> is in fluidic communication with the cannula lumen <NUM> when the adaptor <NUM> is in place. Specifically, the adaptor lumen <NUM> extends through the body <NUM> and shaft <NUM> of the adaptor <NUM>, and ends at the opening <NUM> of the distal end of the shaft <NUM>. Therefore, the adaptor lumen <NUM> provides exterior access to the cannula lumen <NUM> of the ECMO system, including the axial flow path <NUM> thereof. The adaptor lumen <NUM> may also be in fluidic communication with a passage <NUM> extending through a side arm <NUM> of the adaptor <NUM>. In such embodiments, any air that may be present in the cannula lumen <NUM> and the adaptor lumen <NUM> may be removed by selective venting through the passage <NUM> of the side arm <NUM>, such as by operation of a valve connected to the side arm <NUM> through vent tubing <NUM>, as in <FIG>.

The adaptor lumen <NUM> is dimensioned to receive an intervention device <NUM> such as wires and catheters, which may be up to about <NUM> French in diameter, or greater in some embodiments. The flange <NUM> of the shaft <NUM> and the connector <NUM> form a hemostatic seal with the side port <NUM>, as mentioned previously, so that blood flowing through the ECMO system will not be lost during vascular access.

Further, the adaptor <NUM> may include a membrane <NUM> opposite of the shaft <NUM> through which a wire, catheter or other suitable diagnostic, therapeutic or other medical intervention device <NUM> may be passed to enter the adaptor <NUM> and gain access to the ECMO system and vascular system. In at least one embodiment, the membrane <NUM> is a hemostatic diaphragm, such as a silicone or other soft biocompatible plastic disc with a perforating slit(s) for access, as is used in insertion sheaths <NUM>. As shown in <FIG>, <FIG>, the membrane <NUM> is disposed in the body <NUM> of the adaptor <NUM> and spans the distance between the edge of the adaptor lumen <NUM> and the outer edge or exterior of the body <NUM>. In other embodiments, the membrane <NUM> is coextensive with a top surface of the adaptor <NUM>, as in <FIG>, <FIG>. In other embodiments, the top surface of the adaptor <NUM> may not be uniformly flat, but may recess in, as in <FIG>. Here, the membrane <NUM> spans from the adaptor lumen <NUM> to the outer edge of the body <NUM>, which is the recessed portion. Regardless of configuration, the membrane <NUM> allows access to the adaptor lumen <NUM> while maintaining hemostatic conditions and preventing back bleeding upon insertion of an intervention device <NUM> therein.

The invention also includes various systems for vascular access <NUM>. Each system <NUM> includes a cannula <NUM> and an adaptor <NUM> as described herein. For instance, at least one embodiment of a vascular access system 200a includes a cannula <NUM> and an adaptor 30a having a curved shaft 33a, as in <FIG>. In at least one other embodiment, the vascular access system 200b includes a cannula <NUM> and an adaptor 30b having a straight shaft 33d terminating in an angled deflector <NUM>, as in <FIG>. In at least one other embodiment, the vascular access system 200c includes a cannula <NUM> and an adaptor 30c having a straight shaft 33c and a flat terminal end, with an internal deflector <NUM>, as in <FIG>. These are just a few illustrative examples, and are not intended to be limiting.

<FIG> show a modified cannula <NUM> that can be used in an ECLS system in place of a standard arterial cannula <NUM>, such as an ECMO vascular cannula. The modified cannula <NUM> is made of a flexible medical-grade plastic, silicon, or polymer material, or other material suitable for insertion and residence in a patient. As depicted in <FIG> and <FIG>, the modified cannula <NUM> includes an elongate portion <NUM> extending between a proximal end 29a and an opposite distal end 29b. The proximal end 29a is positioned closest to the pump of the bypass system, and has an opening at its terminal end and a diameter sized to receive and form a tight seal with the bypass tubing 3b around its perimeter. For example, such bypass tubing 3b may be <NUM>/<NUM> inch to <NUM>/<NUM> inch (<NUM> to <NUM>) in diameter, and the proximal end 29a may have a diameter ranging from <NUM> to <NUM> French depending on the particular application and whether it is used on an adult, child or infant. In some embodiments, the proximal end 29a includes ribs, barbs, serrations, or other frictional elements that engage the interior of the bypass tubing 3b upon insertion and maintains or facilitates a tight seal with the tubing 3b. Accordingly, when attached to the bypass tubing 3b, the proximal end 29a of the modified cannula <NUM> receives blood from the ECLS system, such as an ECMO system.

The opposite distal end 29b of the modified cannula <NUM> is dimensioned to be inserted into a subject or patient, such as a blood vessel for vascular access, and more in particular an artery, such as the femoral artery or aorta, or a vein, such as the femoral vein or internal jugular vein. For instance, the distal end 29b may have a diameter ranging from <NUM> to <NUM> French, although smaller or larger sizes are also contemplated. The distal end 29b is preferably narrower than the proximal end 29a, as in <FIG> and <FIG>. In other embodiments, however, the distal end 29b and proximal end 29a may have the same diameter, or the distal end 29b may have a larger diameter than the proximal end 29a. The distal end 29b is also made of a flexible medical-grade plastic, silicon, or polymer material, or other suitable material, so as to avoid damaging or puncturing the blood vessel. The distal end 29b may also include an opening(s) at or near the distal tip to allow reinfusion of blood into the surrounding blood vessel from the modified cannula <NUM>.

Between the proximal end 29a and distal end 29b, the modified cannula <NUM> may include a depth guide(s) <NUM> located along the length of the elongate portion <NUM>. The depth guide(s) <NUM> provide a visual indicator for a user, such as a medical practitioner, of how far to insert the distal end 29b of the modified cannula <NUM> into the subject. For instance, in at least one embodiment, the distal end 29b of the modified cannula <NUM> is inserted into the patient at an incision point until the depth guide(s) <NUM> reaches the incision. The depth guide(s) <NUM> therefore provides a maximum limit for insertion. In at least one embodiment, the depth guide <NUM> may be a collar or series of collars disposed circumferentially around the exterior of the elongate portion <NUM> of the modified cannula <NUM>. In other embodiments, the depth guide <NUM> may be a marking or series of markings on or integrally formed in the wall of the modified cannula <NUM>, such as printed on or engraved in the exterior surface of the modified cannula <NUM>.

The modified cannula <NUM> also includes a modified cannula lumen <NUM> extending through the length of the modified cannula <NUM> from the opening at the proximal end 29a to the opening at the distal end 29b. Accordingly, the modified cannula lumen <NUM> provides an axial flow path <NUM>' through which fluid, such as blood, may pass during ECMO circulation. The modified cannula lumen <NUM> has a diameter similar to that of the modified cannula <NUM>, and in at least one embodiment takes up a majority of the inner volume of the modified cannula <NUM>.

As shown in <FIG> and <FIG>, the modified cannula <NUM> further includes an angled side port <NUM> that extends from the surface of the modified cannula <NUM>. Notably, the angled side port <NUM> extends away from the surface at an angle, which may be any angle other than <NUM>°. For instance, the angled side port <NUM> extends from the surface of the modified cannula <NUM> at an acute angle less than <NUM>°, such as in the range of <NUM>° to <NUM>° from the modified cannula <NUM> wall in at least one embodiment. In another embodiment, the angle of the angled side port <NUM> is in the range of <NUM>° to <NUM>°. These are illustrative examples, and are non-limiting. For instance, depending on the perspective, the angled side port <NUM> could be considered to extend at an obtuse angle from the modified cannula <NUM>.

The angled side port <NUM> terminates at a lip <NUM> having a wider diameter than the rest of the angled side port <NUM>, so as to form an overhanging portion. The angled side port <NUM> may also have a thread to allow interaction with Luer connections or other counterthreads on the connector <NUM> of adaptors <NUM>. The angled side port <NUM> also has an opening at the terminal end, and an angled side port channel <NUM> extending through the angled side port <NUM> in fluid communication with the opening on one end and the modified cannula lumen <NUM> on the opposite end. Accordingly, the angled side port <NUM> provides exterior access to the modified cannula lumen <NUM>, and therefore to the vascular system for endovascular diagnostic and therapeutic procedures.

The angled side port <NUM> of the modified cannula <NUM> provides a number of benefits over the standard right angle side ports <NUM> of current vascular arterial cannulas <NUM>. For instance, the angle of the angled side port <NUM> directs an incoming wire, catheter or other inserted medical device to more closely align with the modified cannula lumen <NUM> in a direction toward the heart of the patient. This facilitates the insertion of such a device without having to navigate around a right angle, as with standard cannulas <NUM>, thereby preventing kinking and obstruction of the wire or catheter.

Cardiopulmonary bypass cannulas with an angled side arm or a Y-shape have been described in the prior art. However, these cannulas have several disadvantages that limit their utility in an ECMO system. For instance, when a typical bypass cannula is inserted into a vessel, it may occlude blood flow to distally located tissues. As shown in <FIG>, when a cannula is inserted into the femoral artery, blood flow to the entire ipsilateral leg may be jeopardized. In order to prevent ischemia of distal tissue beds, the right angle side port <NUM> of a cannula <NUM> can be used to establish a secondary circuit <NUM> to direct a portion of the blood flow in the opposite direction to the cannula <NUM>. Blood flow may be directed out of the right angle side port <NUM> of the cannula <NUM> and down the ipsilateral leg to separately perfuse the leg. Secondary circuits for distal perfusion are not always necessary, and may not be needed the entire time the patient is supported on the ECMO system, but they are frequently used. Thus, the ability to establish of a downstream flow circuit is an important option when using long-term bypass systems such as ECMO. However, cardiopulmonary bypass cannulas with angled side arm previously described in the prior art lacks the requisite structure to establish a connection for a secondary circuit <NUM> for distal perfusion.

In contrast, the modified cannula <NUM> with angled side port <NUM> includes a lip <NUM> at the terminal end, as seen in <FIG>. This lip <NUM> provides a surface on which a connector, such as a Luer connector, can be used to engage for secure yet selectively removable connection. Accordingly, a Luer connector commonly used as a secondary tubing connector <NUM>, shown in <FIG>, can engage the lip <NUM> of the angled side port <NUM> of the modified cannula <NUM>, shown in <FIG>, to establish a secondary circuit as previously described for distal perfusion. For example, the lip <NUM> of the angled side port <NUM> is dimensioned to fit within the grooves, threads, or tracks of a connector, such as a Luer connector having internal threading for connection by screwing action. Common cardiopulmonary bypass cannulas, even those with angled side arms, lack this structure. Although Luer connectors are described here as removably engaging the lip <NUM> of the angled side port <NUM>, it should be appreciated that other types of connectors could also be used to removably engage the lip <NUM> for a secure connection, such as snap on connectors.

In addition, in an ECMO circuit, blood flow along the main lumen <NUM> of the cannula <NUM> is laminar. A typical angled side arm represents an arm with a blind end, since laminar flow does not penetrate the side arm. The lack of flow in the side arm creates a potential for stagnant blood to pool in the side arm, which may result in thrombus formation, particularly during periods of prolonged support on ECMO. If a thrombus forms and is later dislodged, it may result in devastating complications including stroke, myocardial infarction, ischemic bowel, or ischemia of other tissues. Therefore, known cardiopulmonary bypass cannulas with an angled side arm or a Y-shape cannot be used in ECMO systems. Further, many cardiopulmonary bypass cannulas with an angled side arm or a Y-shape have permanent valves located within the side arm. Such permanent valves may increase the risk of stagnant blood flow and thrombus formation. The angled side port <NUM> of the modified cannula <NUM> lacks such permanent valves that would lead to stagnant blood flow and thrombus formation.

In addition, the angled side port <NUM> of the modified cannula <NUM> is designed to coordinate with a specialized occlusive cap <NUM> for use when access to a secondary circuit <NUM> or endovascular access is not needed. Specifically, the occlusive cap <NUM> is designed to fit inside the angled side port channel <NUM> of the angled side port <NUM> and occlude substantially all of the angled side port <NUM>, such that blood does not flow into the angled side port <NUM> from the ECMO system when access is not needed. This prevents blood stagnation and potential thrombus formation, and is not available with known ECMO or cardiovascular bypass cannulas.

As seen in <FIG> and <FIG>, at least a portion of the occlusive cap <NUM> is correspondingly dimensioned in size and shape to fit inside the angled side port channel <NUM> and provide a tight fit therein. Specifically, the occlusive cap <NUM> includes an occluding member <NUM> terminating in an occluding surface <NUM>, as seen in <FIG>, <FIG>, <FIG>. The occluding surface <NUM> blocks the angled side port channel <NUM> and prevents blood from entering. It therefore prevents blood stagnation and potential thrombus formation. As depicted in the cross-section of <FIG> and the view along line <NUM>-<NUM> shown in <FIG>, the edges of the occluding surface <NUM> are adjacent to and abut the interior surface of the angled side port channel <NUM>, so as to form a tight fit therewith. In a preferred embodiment, as in <FIG>, the occluding surface <NUM> is flush or coextensive with the wall of the modified cannula lumen <NUM>, such that the occluding member <NUM> of the occlusive cap <NUM> does not extend into the modified cannula lumen <NUM> and laminar blood flow through the modified cannula lumen <NUM> is not disrupted. However, in some embodiments the occluding member <NUM> may extend into the modified cannula lumen <NUM>, such as to ensure the angled side port channel <NUM> is entirely blocked.

In some embodiments, the occluding surface <NUM> may have a locking member <NUM>, as shown in <FIG>. This locking member <NUM> is located along the perimeter of the occluding surface <NUM> and is correspondingly dimensioned with a receiver <NUM> located in the inner perimeter or edge of the angled side port <NUM>, such as in the angled side port channel <NUM>. As illustrated through <FIG>, the locking member <NUM> and receiver <NUM> correspondingly fit together to form a tight fit, but may also provide locking engagement for securely retaining the occluding surface <NUM> in the angled side port <NUM> in a particular orientation. This engagement may also be used to ensure the occlusive cap <NUM> is fully inserted and/or properly aligned within the angled side port channel <NUM> so that the occluding surface <NUM> is flush or fully coextensive with the wall of the modified cannula lumen <NUM>, as the locking member <NUM> and corresponding receiver <NUM> may only interact and engage in a particular configuration. In at least the embodiment shown in <FIG>, the locking member <NUM> is an extension that extends from the perimeter of the occluding surface <NUM>, and the receiver <NUM> is a recess formed in the angled side port <NUM> having a corresponding shape, contour and dimension to the locking member <NUM>. However, it should be understood that in other embodiments, the locking member <NUM> may be located in the angled side port <NUM> and the receiver <NUM> may be located in the perimeter of the occluding surface <NUM>. Similarly, the locking member <NUM> and receiver <NUM> may have any shape, dimension or contour permitted by the occluding surface <NUM> and angled side port <NUM>, so long as they coordinate together. For example, the locking member <NUM> may be a keyed extension, the receiver <NUM> may be a rail or track, and either or both the locking member <NUM> and receiver <NUM> may include threading for coordinated interaction. These are just a few illustrative examples, and are not meant to be limiting.

In at least one embodiment, the occluding member <NUM> may have an elongate shape, such as a cylinder or shaft that extends at least a portion of the length of the occlusive cap <NUM>. In some embodiments, the occluding member <NUM> extends the entire length of the occlusive cap <NUM>. At least a portion of the occluding member <NUM> has a diameter that is substantially the same as or slightly smaller than the diameter of the angled side port channel <NUM>. In one embodiment, the entire length of the occluding member <NUM> has a diameter corresponding to the diameter of the angled side port channel <NUM> of the modified cannula <NUM>. In other embodiments, however, only a portion of the occluding member <NUM> has a diameter corresponding to the diameter of the angled side port channel <NUM>. This portion may be located anywhere along the occluding member <NUM>, such as at an end or anywhere along the length of the occluding member <NUM>.

Regardless of the length and diameter of the occluding member <NUM>, it terminates at the occluding surface <NUM> on one end, as depicted in <FIG>. Therefore, the occluding member <NUM> may be at least as long as the angled side port channel <NUM> and the angled side port <NUM> in some embodiments. In a preferred embodiment, the occluding member <NUM> is the same length as the angled side port channel <NUM>. In some embodiments, the width or diameter of the occluding member <NUM> is the same as that of the occluding surface <NUM>. In other embodiments, the width or diameter of the occluding member <NUM> is less than that of the occluding surface <NUM>, or may vary in its diameter over its length.

At the opposite end of the occluding member <NUM> from the occluding surface <NUM>, the occlusive cap <NUM> may also include a cap connector <NUM>, as shown in <FIG>. The cap connector <NUM> selectively retains the occlusive cap <NUM> on the modified cannula side port <NUM> for selectively reversible securing. For instance, the cap connector <NUM> is dimensioned to removably engage the lip <NUM> of the angled side port <NUM> to secure the occlusive cap <NUM> in place upon insertion into the angled side port <NUM>. Tthe cap connector <NUM> may be shaped as a Luer connector, such as a floating or fixed Luer connector, and may include threads disposed along an inner surface for receiving the lip <NUM> of the angled side port <NUM>. Of course, other forms of selectively reversible attachment are also contemplated, and are not limited to threaded engagement. The cap connector <NUM> may be integrally formed with the occlusive cap <NUM>, as in <FIG>, although in other embodiments it may be formed separately and attached to the occlusive cap <NUM>, such as at the occluding member <NUM>. The cap connector <NUM> allows the occlusive cap <NUM> to be secured to the angled side port <NUM> when the modified cannula <NUM> does not need to be accessed. However, it is selectively reversible to permit removal of the occlusive cap <NUM> for access to the modified cannula <NUM> through the angled side port <NUM>, such as to establish a secondary circuit as previously discussed or to insert a wire, cannula or other medical device.

Accordingly, the occlusive cap <NUM> and modified cannula <NUM> described herein together form an occlusion system <NUM>, as seen in <FIG>. When the occlusive cap <NUM> is fully inserted in the angled side port <NUM> of the modified cannula <NUM>, the laminar blood flow through the bypass system is substantially entirely occluded from the angled side port <NUM>. This is important to prevent thrombus formation in long-term use systems such as ECLS.

When access to the modified cannula lumen <NUM> is desired, such as for the insertion of a wire or catheter or to establish a secondary circuit for distal perfusion, the occlusive cap <NUM> may be removed from the angled side port <NUM>. The bypass tubing 3b may be clamped upstream of the modified cannula <NUM> prior to removal of the occlusive cap <NUM>, such that blood flow through the system is temporarily interrupted. This prevents blood from seeping into the angled side port channel <NUM> upon removal of the occluding surface <NUM> and the occlusive cap <NUM>. Once the occlusive cap <NUM> is removed, secondary circuit tubing may be connected to the angled side port <NUM> in a similar fashion as it would connect to a right angle side port <NUM>. The clamp on the bypass tubing 3b may then be released, reestablishing the blood flow through the system, which now includes a secondary circuit for distal perfusion. On the other hand, if endovascular access is desired, such as through the insertion of a wire or catheter, an adaptor 30d may be attached to the angled side port <NUM> during temporary interruption of the ECMO system, as described below. After either is attached, the clamp may be removed and ECMO flows reinstituted.

The present disclosure also includes an adaptor 30d, as seen in <FIG> and <FIG>. Because the adaptor 30d and occlusive occlusive cap <NUM> are interchangeable, the adaptor 30d may also be considered an insertion cap, and the terms are used interchangeably herein. The adaptor/insertion cap 30d includes a body <NUM>, a membrane <NUM> for hemostatic access, and an adaptor or insertion lumen 31d extending from the membrane <NUM> and through the body <NUM>, similar to those of the previously described adaptors 30a,b,c. However, the adaptor/insertion cap 30d is used with the angled side port <NUM> of the modified cannula <NUM> to permit exterior access to the modified cannula lumen <NUM>, and thus the ECMO system for endovascular entry. The adaptor 30d need not provide directionality for the insertion of a wire or catheter since that function is already provided by the angle of the angled side port <NUM>. Therefore, in at least one embodiment the adaptor/insertion cap 30d may not include a shaft <NUM> or other structure that extends into the angled side port channel <NUM> of the angled side port <NUM>. In such embodiments, the adaptor or insertion lumen 31d is in fluid communication with the angled side port channel <NUM> when the adaptor/insertion cap 30d is connected to the angled side port <NUM>. In other embodiments, as in <FIG> and <FIG>, the adaptor/insertion cap 30d includes a shaft 33d. The adaptor lumen 31d is sized to coordinate with the angled side port channel <NUM>, and may be the same or similar diameter as the angle side port channel <NUM>. The adaptor lumen 31d is sized to allow the passage of wires, catheters and other medical devices that may be used for cardiovascular interventions, such as <NUM> French or greater. Accordingly, an intervention device <NUM> can be passed through the hemostatic membrane <NUM> and enter the adaptor lumen 31d, pass through the adaptor lumen 31d directly into the angled side port channel <NUM>, and on into the modified cannula lumen <NUM>.

In other embodiments, the adaptor/insertion cap 30d may include a shaft 33d that is straight and may be shorter than the shafts 33a,b,c of the previously discussed adaptors 30a,b,c. When present, the shaft 33d may extend into at least a portion of the angled side port channel <NUM>, or even into the modified cannula lumen <NUM>. Accordingly, in some embodiments, the shaft 33d may be <NUM> French in diameter or greater, such as to permit the passage of intervention devices such as medical devices for cardiovascular intervention, but still fits within the angled side port channel <NUM>. The shaft 33d may be integrally formed in the body <NUM> of the adaptor/insertion cap 30d, or may attach to the body <NUM> such as by secure attachment as with adhesive or molding.

The adaptor/insertion cap 30d may attach to the exterior of the angled side port <NUM>, such as by engaging the lip <NUM> of the angled side port <NUM> with a connector <NUM> as previously described. Because directionality is not a function of the adaptor 30d with an angled side port <NUM>, the connector <NUM> of the adaptor 30d may be fixed, formed in or integral with the body <NUM> of the adaptor 30d, as shown in <FIG>. Thus, when the adaptor 30d is attached to the angled side port <NUM>, the entire body <NUM> may be rotated around the angled side port <NUM>, to provide a secure, selectively reversible connection such as by screw-type action of threading of the connector <NUM> with the lip <NUM> of the angled side port <NUM>. Of course, in other embodiments, the connector <NUM> may be a floating Luer connector as previously described, or a retaining structure that permits the adaptor 30d to slide or snap onto the lip <NUM> of the angled side port <NUM>, whereby the lip <NUM> retains the adaptor/insertion cap 30d in place.

Accordingly, the present disclosure also include another embodiment of a vascular access system 200d including a modified cannula <NUM> having an angled side port <NUM> and an adaptor/insertion cap 30d having a shorter shaft 33d as described above, such as depicted in <FIG>. The adaptor/insertion cap 30d, and specifically the shaft 33d, provides exterior access of an intervention device <NUM> to the modified cannula lumen <NUM> so as to change the angle of insertion of the insertion device <NUM> to be inline with or consistent with the axial flow path <NUM>'. In addition, the cannula may not be limited to one side port. For example the cannula may have one or more angled side ports, right angle side ports, or some combination thereof.

In addition, the present disclosure also includes a tube coupler <NUM> that may be inserted or spliced into ECMO or any bypass tubing to provide additional side ports <NUM>, <NUM> for endovascular access. For instance, some patients arrive at a medical facility with an ECMO or other ECLS system already in place, in which the arterial cannula <NUM> may not have a side port <NUM> for endovascular access, and yet endovascular access may become necessary at some point while the patient is on support. In other instances, the arterial cannula <NUM> of the ECLS system may only have a single side port <NUM>, but multiple devices (such as wires, catheters, etc.) may be needed to be inserted at the same time for simultaneous endovascular access, such as for coordinated actions to perform a medical procedure. The side port <NUM> and its hemostatic membrane <NUM> may allow only one device through at a time, in order to maintain the hemostatic seal and prevent back bleeding. Since multiple couplers could be inserted into an ECLS circuit, the tube coupler <NUM> of the present disclosure therefore provides a way to introduce additional side ports <NUM>, <NUM> for additional points of access to the ECMO or other ECLS system.

As seen in <FIG>, the tube coupler <NUM> includes a first end <NUM> having a first end opening <NUM>, and an opposite second end <NUM> with a second end opening <NUM>, and a coupler body <NUM> disposed there between. The first and second ends <NUM>, <NUM> are sized and shaped to accommodate and selectively matingly fit independent or separate sections of bypass tubing 3b, such as ECMO tubing, on an arterial side of the bypass system. The first and second ends <NUM>, <NUM> may be slightly narrower in diameter than the coupler body <NUM> of the tube coupler <NUM>, and in some embodiments may taper slightly, to allow a tight hemostatic seal when the tubing 3b is attached. In some embodiments, the first and second ends <NUM>, <NUM> may have ribs, barbs, serrations, beveling, or other frictional structure to promote a tight seal and retention of the ECMO or bypass tubing 3b. Accordingly, the first and second ends <NUM>, <NUM> may have a similar structure to the proximal end 9a of a standard arterial cannula <NUM>, as discussed previously, although it is not required. In some embodiments, the first and second ends <NUM>, <NUM> have the same diameters and structural features. In other embodiments, the first and second ends <NUM>, <NUM> may have different diameters and structural features from one another.

The coupler body <NUM> extends between the first and second ends <NUM>, <NUM> and may have an elongate length. In a preferred embodiment, the coupler body <NUM> may be a cylinder, although other shapes and configurations are contemplated. A coupler lumen <NUM> extends through at least a portion of the tube coupler <NUM> at the coupler body <NUM>. In at least one embodiment, the coupler lumen <NUM> extends from the first end opening <NUM> to the second end opening <NUM> and through the coupler body <NUM> such that the coupler lumen <NUM> provides an axial flow path <NUM>' for fluid such as blood to flow entirely through the tube coupler <NUM> when inserted in a bypass system. The coupler lumen <NUM> thus allows the tube coupler <NUM> to be inserted into, and become part of, an established bypass system and permit the continued functioning of the bypass system.

The tube coupler <NUM> further includes a access port <NUM> located along the coupler body <NUM>. The access port <NUM> may be a right angle side port <NUM>, as shown in <FIG>, such as is provided on commercially available arterial cannulas <NUM> as described above. Specifically, the access port <NUM> includes a length that extends away from the coupler body <NUM> of the tube coupler <NUM>. The access port <NUM> defines an access port channel <NUM> extending through at least a portion of the interior of the access port <NUM>, which is in fluid communication with the coupler lumen <NUM> at one end, and has an opening at the other end for receiving the shaft <NUM> of an adaptor <NUM> as previously described, such as adaptors 30a,b,c. Accordingly, the access port channel <NUM> provides exterior access to the coupler lumen <NUM> such that a wire, catheter or other intervention device <NUM> may be inserted through a hemostatic membrane <NUM> within such adaptor <NUM>, as previously described, and be inserted into the access port channel <NUM> of the tube coupler <NUM>, and on into the coupler lumen <NUM> consistent with the axial flow path <NUM>' and bypass tubing 3b.

In other embodiments, as seen in <FIG>, the tube coupler <NUM>' includes an angled access port <NUM>', such as the angled side port <NUM> previously described in connection with the modified cannula <NUM>. Accordingly, it should be appreciated that the tube coupler <NUM>, <NUM>' may include a traditional access port <NUM> or angled access port <NUM>' providing an access point to the interior of the tube coupler <NUM>, <NUM>', and therefore, the endovascular system. The angled access port <NUM>' is located along the coupler body <NUM> of the tube coupler <NUM>', and may have any angle relative to the coupler body <NUM> as may promote ease of insertion of intervention devices <NUM>. For instance, as previously discussed, the angle of the angled access port <NUM>' may be any angle between <NUM>° up to <NUM>°. The angled access port <NUM>' extends from the coupler body <NUM> and defines an angled access port channel <NUM>' extending through at least a portion of the interior of the angled access port <NUM>', which is in fluid communication with the coupler lumen <NUM> at one end, and has an opening at the other end for receiving an adaptor/insertion cap 30d and/or shaft 33d as previously described. Accordingly, the angled access port channel <NUM>' provides exterior access to the coupler lumen <NUM> and axial flow path <NUM>" therein such thata wire, catheter or other intervention device <NUM> may be inserted through a hemostatic membrane <NUM> within such adaptor 30d, as previously described, and be inserted into the access port channel <NUM>' and axial flow path <NUM>" of the tube coupler <NUM>', and on into the coupler lumen <NUM> and bypass tubing 3b, as shown in <FIG>.

The tube coupler <NUM>' may also coordinate with the adaptor/insertion cap 30d and occlusive cap <NUM> as previously described, either to provide endovascular access through the tube coupler <NUM>' or to seal off and occlude the angled access port <NUM>' when access is not desired. Accordingly, the tube coupler <NUM>, <NUM>' may comprise a part of a vascular access system <NUM>, <NUM>', respectively, in conjunction with an adaptor <NUM> as described herein, such as in <FIG>. The tube coupler <NUM>, <NUM>' may also be part of an occlusion system <NUM>' in conjunction with a occlusive cap <NUM>, as in <FIG>. The angled access port <NUM>' of the tube coupler <NUM>' can also be used to establish a secondary circuit for distal perfusion, as previously described.

<FIG> demonstrate the steps of inserting a tube coupler <NUM>, <NUM>' into an already established ECLS system. A tube coupler <NUM>' with angled access port <NUM>' is shown, but it should be appreciated that a tube coupler <NUM> with a right angle access port <NUM> would be inserted in a similar manner. To begin, as in <FIG>, a location along the bypass tubing 3b where the tube coupler <NUM>' is to be inserted is identified. This location may be anywhere in the bypass system, but is preferably on the arterial side of the bypass system. In at least one embodiment, the location is proximate to, and upstream or proximal to, the location for intervention device use.

Once an insertion location is identified, the bypass system is temporarily interrupted, such as by clamping, crimping or otherwise restricting the bypass tubing 3b on either side, or at least upstream of, the insertion location. This prevents the flow of blood through the ECMO system, and allows the tubing to be cut without loss of blood. The bypass tubing 3b is then cut downstream of the restriction point, resulting in two pieces of bypass tubing, as seen in <FIG>. The proximal piece 3b' of bypass tubing is located with the restriction point, and is closer to the pump of the ECMO system. The distal piece 3b" of bypass tubing is located downstream of the cut in the tubing, and is closer to the arterial incision <NUM> where the bypass system is reintroduced back into the subject or patient.

Once the tubing 3b is cut, the tube coupler <NUM>' is then inserted between the proximal piece 3b' and distal piece 3b" of bypass tubing, as shown in <FIG>. For instance, the first end <NUM> of the tube coupler <NUM>' is joined to the proximal piece 3b' of the bypass tubing, and the opposite second end <NUM> of the tube coupler <NUM>' is joined to the distal piece 3b" of bypass tubing. The first and second ends <NUM>, <NUM> of the tube coupler <NUM>' will be oriented such that the angled access port <NUM>' opens toward the proximal piece 3b' of bypass tubing, such that an intervention device <NUM> inserted therein is directed toward the distal piece 3b" and toward the heart of the subject. When the tube coupler <NUM>' is first inserted and joined to the proximal and distal pieces 3b', 3b" of the bypass tubing, an occlusive cap <NUM> may already be inserted in the angled side port <NUM> in a fully occluding position.

Once the bypass tubing is joined and a hemostatic seal is established at the first and second ends <NUM>, <NUM>, the clamp or other restriction device temporarily interrupting the flow through the bypass system is removed, and flow through the system is re-established. The coupler lumen <NUM> is in fluid communication with both the proximal piece 3b' and distal piece 3b" of bypass tubing, defining a flow path with the tubing such that as blood flows through the bypass tubing it enters the proximal piece 3b', then the coupler lumen <NUM>, then the distal piece 3b" of bypass tubing on its path from the oxygenator to the patient's heart. When the occlusive cap <NUM> is included in the angled access port <NUM>' of a tube coupler <NUM>', or when a standard cap is inserted in the right angle access port <NUM> of a tube coupler <NUM>, the access port channel <NUM>, <NUM>' is occluded and blood is prevented from pooling and stagnating in the access port <NUM>, <NUM>'.

When access to the bypass system is desired, such as to establish a secondary circuit as previously described or to gain endovascular access for medical intervention, the occlusive cap <NUM> may be removed from the access port <NUM>, <NUM>', as depicted in <FIG>. An adaptor 30d, as previously described, is then inserted and attached to the access port <NUM>, <NUM>', as shown in <FIG>. Once the adaptor 30d is in place, an intervention device <NUM> such as a wire or catheter or other suitable device may be inserted into the tube coupler <NUM>', as in <FIG>. Specifically, the intervention device <NUM> enters through the membrane <NUM> of the adaptor 30d and continues to advance through the shaft 33d, into the coupler lumen <NUM>, and on into the distal piece 3b" of bypass tubing until the particular site for intervention is reached.

Claim 1:
An adaptor (<NUM>, 30a, 30b, 30c) for
providing access to an interior of a cannula (<NUM>, <NUM>), said cannula (<NUM>, <NUM>) having two ends, a cannula lumen (<NUM>, <NUM>) extending between said ends establishing an axial flow path (<NUM>, <NUM>', <NUM>"), and a side port (<NUM>) extending at a right angle from said cannula (<NUM>, <NUM>) having a side port channel (<NUM>) providing access to said cannula lumen (<NUM>, <NUM>) through a right angle, said adaptor (<NUM>, 30a, 30b, 30c) comprising a shaft (33a, 33b, 33c) configured to protrude into the cannula lumen (<NUM>, <NUM>) and to provide exterior access to said cannula lumen (<NUM>, <NUM>) through an adaptor lumen (31a, 31b, 31c) in said shaft (<NUM>, 33a, 33b), said adaptor lumen (31a, 31b, 31c) being further configured to receive an intervention device (<NUM>) inserted therein;
said shaft (<NUM>, 33a, 33b) of said adaptor lumen (31a, 31b, 31c) being a curved shaft (33a) or straight shafts (33b, 33c) having an angle, said adaptor lumen (31a, 31b, 31c) having a distal terminal opening (<NUM>) configured to be exposed with said cannula lumen (<NUM>, <NUM>) , said shaft (33a, 33b, 33c) being configured to modify an angle of insertion of said intervention device (<NUM>) through said adaptor lumen (31a, 31b, 31c) thereby and to direct said intervention device (<NUM>) within said cannula lumen (<NUM>, <NUM>) through said right angle of said side port channel (<NUM>) in a direction consistent with said axial flow path (<NUM>, <NUM>', <NUM>").