Closed suction catheter adapter with flush arrangement

A respiratory apparatus including an adapter assembly and a catheter assembly. The adapter assembly includes ventilator, respiratory, access, and flush ports. The access port includes a conduit defining a passageway. The flush port projects from the conduit and is fluidly open to the passageway at an outlet. The catheter assembly includes a catheter assembled to a fitting. The fitting includes a hub and a tube, with the tube defining an exterior surface, an interior surface forming a lumen, a circumferential groove in the exterior surface, and a plurality of apertures fluidly open to the lumen and the circumferential groove. The tube is sized to be slidably received within the passageway such that upon final assembly, a fluid pathway is formed between the flush port and a distal end of the catheter via the flush port outlet, the circumferential groove, the plurality of apertures, and the lumen.

BACKGROUND

The present disclosure relates generally to airway access adapters used in respiratory applications. More particular, it relates to adapters and related closed suction catheter systems with enhanced cleaning or flushing capabilities, as well as optional valve configurations useful therewith.

Use of ventilators and related breathing circuits to assist in patient breathing is well known in the art. For example, during surgery and other medical procedures, the patient is often connected to a ventilator to provide respiratory gases to the patient. In many instances, the mechanical ventilation is connected into the patient's respiratory tract via an artificial airway, such as a tracheostomy tube, endotracheal tube, etc.

While the breathing circuit can establish a single, direct fluid connection between the ventilator and the artificial airway, in many instances, caregivers desire the ability to introduce instruments and/or materials into the breathing circuit. To satisfy these needs, airway access adapters have been developed. In general terms, an airway access adapter is a manifold-type body providing at least three fluidly connected ports including a ventilator port, a respiratory port, and an access port. During use, the airway access adapter is assembled to the breathing circuit with the ventilator fluidly connected to the ventilator port and the artificial airway fluidly connected to the respiratory port. With this configuration, the access port enables caregivers to, for example, insert instruments for visualization or related procedures, or to aspirate fluid or secretions from the patient's airway. Typically, the airway access adapter provides a seal or valve configuration across the access port so that pressures required to maintain ventilation of the patient are not lost via the access port. Airway access adapters are well accepted, and are highly beneficial especially with patients requiring long-term mechanical ventilation.

As indicated above, the airway access adapter facilitates use of a variety of different tools within the breathing circuit. One such tool is a closed suction catheter system used to remove secretions or fluids from the airways of a ventilated patient. To prevent loss of ventilating pressures, the catheter is made part of the sealed breathing circuit so that the circuit does not need to be “opened” in order to suction the patient's airways. Additionally, so that the catheter can remain uncontaminated by environmental micro-organisms, or contaminated by caregivers, the closed suction catheter system oftentimes includes a sheath that covers the portion of the catheter outside the breathing circuit. With this configuration, the closed suction catheter system can be left attached to the breathing circuit (via the airway access adapter) between suctioning procedures. Over time, however, secretions and other materials may accumulate at the working end of the catheter, necessitating periodic cleaning of the catheter. One common cleaning approach entails flushing the catheter end with a fluid such as saline or water to maintain patency and to prevent a stagnation of a media for bacterial growth.

Existing closed suction catheter systems and related airway access adapters employ one of two configurations that enable flushing of the suction catheter system. With one approach, the suction catheter is readily removed from the airway access adapter, and incorporates a flush port otherwise attached to the suction catheter components that facilitates cleaning. With this approach, the flush port is removed from the airway access adapter along with other components of the suctioning catheter system. Conversely, where the suction catheter system (and related airway access adapter) is solely for closed suction applications (i.e., the catheter cannot be detached from the airway access adapter), a flush port is provided with the airway access adapter itself. Since the catheter cannot be removed, the flush port is located so as to introduce the cleaning fluid near the tip of the catheter when the catheter is fully withdrawn from the patient's airway and into the protective sheath.

While the two suction catheter cleaning configurations described above are highly useful, certain drawbacks remain. With removable catheter/flush port designs, other instruments passed into the access port of the airway access adapter (following the removal of the closed suction catheter system) are not easily cleaned. That is to say, once the flush port is removed, it is no longer available for facilitating cleaning of other instruments. Conversely, with available airway access adapters incorporating a flush port, the suction catheter is not readily removed, and cannot be replaced with other instruments, thus limiting an overall usefulness of the adapter. Along these same lines, modifying an airway access adapter having a flush port to removably accept a suction catheter (via a slip fit seal) would result in the slip fit seal blocking the flush port, and thus is not viable.

In addition to the drawbacks associated with current flush port configurations, airway access adapters commonly include a valve of some type that closes the access port during periods of non-use, and promotes sealed insertion of various instruments therethrough. In this regard, conventional check valves and/or flap valves are widely employed, but long-term, repeated sealing of the valve is less than optimal.

In light of the above, needs exist for improved airway access adapters as well as closed suction catheter systems used therewith.

SUMMARY

One aspect provides a respiratory apparatus for connecting a respiratory device to an artificial airway of a patient, including an adapter assembly and a catheter assembly. The adapter assembly has a ventilator port for connection to a ventilating device, a respiratory port for connection to an artificial airway, an access port, and a flush port. The access port has a conduit defining a passageway extending from an open, insertion end. The flush port projects from the conduit and fluidly opens to the passageway at a flush port outlet. The catheter assembly has a fitting and a catheter. The fitting has a hub and a tube extending from the hub to a trailing end. The tube defines an exterior surface, an interior surface forming a lumen, a circumferential groove in the exterior surface adjacent the trailing end, and a plurality of apertures fluidly open to the lumen and the exterior surface in a region of the circumferential groove. The catheter is assembled to the fitting. The catheter defines a distal end. The tube is sized to be slidably received within the passageway such that upon final assembly, a fluid pathway is formed between the flush port and the distal end of the catheter via the flush port outlet, the circumferential groove, the plurality of apertures, and the lumen.

DETAILED DESCRIPTION

Some aspects in accordance with the present disclosure relate to an airway access adapter for use in a ventilator circuit, along with a closed suction catheter assembly useful with the airway access adapter. With this in mind, one embodiment of a respiratory apparatus20is illustrated inFIG. 1, and includes an airway access adapter assembly (or “adapter assembly”)22and a closed suction catheter assembly24. Details on the various components are provided below. In general terms, however, the adapter assembly22is configured for placement within a patient breathing circuit33, fluidly interconnecting an artificial airway35that is otherwise in direct fluid communication with a patient's respiratory tract (e.g., via an endotracheal tube, tracheostomy tube, etc.) with a source of mechanical ventilation (e.g., tubing connected to a ventilator). Further, the adapter assembly22facilitates removable insertion of instruments into the breathing circuit, including the suction catheter assembly24. To this end, the adapter assembly22and the suction catheter assembly24incorporate corresponding features that promote cleaning of the suction catheter assembly24while the suction catheter assembly24remains attached to the adapter assembly22.

With the above in mind, the adapter assembly22includes a manifold housing30forming or providing a ventilator port32, a respiratory port34, an access port36and a flush port38. As best shown inFIGS. 2A and 2B, the housing30fluidly interconnects the ports32-38, and the adapter assembly22further includes a valve device40adjacent the access port36.

The ventilator port32is illustrated inFIG. 2A, and is configured for fluid connection to a ventilator33(FIG. 1), for example via tubing. In this regard, the adapter assembly22can include additional components useful in establishing and maintaining the desired fluid connection, such as a swivel-type coupling, a seal, etc.

The respiratory port34is configured for fluid connection to an artificial airway35(FIG. 1) otherwise establishing a direct connection to the patient's respiratory tract. For example, the respiratory port34can be connected to tubing that in turn is fluidly connected to an endotracheal tube or a tracheostomy tube; alternatively, the artificial airway35can be directly connected to the respiratory port34. Further, the adapter assembly22can include additional components useful in establishing and maintaining the desired fluid connection, such as a swivel-type coupling, a seal, etc.

Regardless of an exact construction of the ventilator port32and the respiratory port34and/or related components such as couplings or seals, the housing30fluidly interconnects the ports32,34. With this construction, then, the adapter assembly22can be inserted into a patient breathing circuit and maintain a necessary fluid connection between the ventilator33and the patient's respiratory tract.

The access port36is configured to allow selective insertion of various instruments into the housing30, and in particular to (and optionally through) the respiratory port34. Thus, in some embodiments, the access port36is axially aligned with the respiratory port34. With specific reference toFIG. 2B, the access port36includes or defines a conduit42establishing a passageway44. The passageway44is open at a proximal or insertion end46of the access port36, with the insertion end46including a flange48extending radially outwardly from the conduit42in some embodiments. Regardless, an inner surface50of the conduit42defines a cross-sectional area of the passageway44that is sized in accordance with one or more instruments commonly used in conjunction with the adapter assembly22, including the suction catheter assembly24as described below.

The flush port38projects from the conduit44adjacent the insertion end46, and is fluidly connected to the passageway44. More particularly, the flush port38forms a channel52extending between, and open relative to, an inlet54and an outlet56. The flush port38can include various features at the inlet54that promote fluid connection to tubing or other components associated with a source of liquid such as water or saline (not shown) useful for cleaning (or “flushing”) a body inserted into the access port36. For example, a barbed surface58is optionally formed. Regardless, the outlet56is formed through or at the interior surface50of the conduit42at a known or predetermined longitudinal position or distance relative to the insertion end46. As described below, the predetermined location of the outlet56relative to the insertion end46corresponds with a dimensional attribute of the suction catheter system24(FIG. 1) to better ensure that liquid introduced at the flush port38interfaces with the suction catheter system24at a desired location.

As a point of reference,FIGS. 2A and 2Billustrate the access port36as being formed by first and second frame or housing portions60,62. The first frame portion60is an integrally formed structure of the manifold30(i.e., the first frame portion60is integrally formed with the ventilator port32and the respiratory port34), with the second frame portion62defining the insertion end46. With this construction, the second frame portion62is assembled to the first frame portion60to complete the access port36, as well as to complete the valve device40. In other embodiments, however, the access port36is a homogeneous body, and does not incorporate two (or more) separable parts. Regardless, the valve device40extends across and fluidly seals the passageway44, and incorporates features that permit selective insertion of an instrument through the access port36. Upon removal of the instrument, the valve device40operates to fluidly seal the passageway44(i.e., seals the insertion end46from the ventilator port32and the respiratory port34). One optional construction of the valve device40is described in greater detail below. In more general terms, the valve device40can assume a variety of forms useful in facilitating sealed insertion and removal of instruments through the access port36(e.g., check valve, duck valve, flapper valve, etc.).

As indicated above, and returning toFIG. 1, the suction catheter assembly24is configured for use with the adapter assembly22via the access port36. With this in mind, one construction of the suction catheter assembly24in accordance with the present disclosure is shown in greater detail inFIG. 3, and includes a catheter70, a flexible sheath72, a fitting74, a seal body76, and a coupler78. Details on the various components are provided below. In general terms, however, the catheter70is slidably assembled to the fitting74via the seal body76. Similarly, the flexible sheath72is mounted to the fitting74via the coupler78. Finally, the fitting74is configured to interface with the access port36(FIG. 1) to permit insertion of the catheter70through the adapter assembly22(FIG. 1), as well as cleaning of the catheter70.

The catheter70can assume a variety of forms currently known, or in the future developed, useful for performing suction procedures on a patient otherwise connected to the breathing circuit. Thus, in some embodiments, the catheter70defines one or more lumens80(referenced generally) through a length thereof, extending from an opening at a distal end82. A side opening84can further be formed that is open to the lumen80. With this configuration, the distal end82may be extended through the artificial airway35(FIG. 1) and into the respiratory tract of the patient (e.g., the patient's lungs). The lumen80is similarly open at a proximal end (not shown) of the catheter70, that in turn can be connected to a vacuum source37(FIG. 1). Upon placement of the distal end82in the patient's respiratory tract and activation of the vacuum source37, respiratory secretions in the patient and in the artificial airway35can be removed.

The flexible sheath72surrounds the catheter70apart from the fitting74, and serves to contain and isolate contaminants and mucus that may accumulate on the catheter70as it is withdrawn from the respiratory tract. In addition, the sheath72protects external contaminants from contacting the catheter70. The sheath72can assume any form useful for closed suction catheter applications, and is typically formed of a thin-walled plastic.

The fitting74includes a hub90and a nose92, and defines a continuous lumen94(referenced generally inFIG. 3) extending longitudinally therethrough. The fitting74can be formed from a rigid, surgically safe material such as stainless steel, plastic, ceramic, etc.

The hub90is sized to receive the seal body76and the coupler78, and to interface with the access port36(FIG. 1) as described below. With this in mind, the hub90is defined by opposing, first and second ends96,98, with the second end98having a diameter corresponding with a dimensional attribute of the access port36to ensure a desired arrangement of the fitting74relative to the access port36upon final assembly. In some embodiments, the hub90includes a flange100maintaining one or more pins102adapted to achieve a mounted relationship with corresponding features of the coupler78, although a wide variety of other mounting techniques are equally acceptable.

The nose92is a tubular body extending from second end98of the hub90, and terminates at a trailing end104. The lumen94is open at the trailing end104, with the nose92sized for insertion into the access port36(FIG. 1). The nose92forms an exterior surface106defining a slightly tapering outer diameter (i.e., from the second end98of the hub90to the trailing end104) in some embodiments. In addition, the nose92forms a circumferential groove108along the exterior surface106adjacent the trailing end104, and one or more apertures110. The groove108can be an undercut machined into the exterior surface106during manufacture of the fitting74. The apertures110extend through a thickness of the nose92, establishing a fluid pathway between the exterior surface106and the lumen94. In some embodiments, four of the apertures110are formed in an equidistantly spaced fashion, and are identical in size and shape. Alternatively, any other number of the apertures110(greater or lesser) is acceptable and/or the apertures110need not be identical. Regardless, the aperture(s)110are formed within a region of the groove108.

A relationship of the groove108and the apertures110is further reflected in the view ofFIG. 4. As shown, the apertures110are circumferentially spaced within the groove108(e.g., centered relative to a longitudinal height of the groove108), and are open to the lumen94. Further, the groove108(and thus the apertures110) is located at a known or predetermined longitudinal distance relative to the second end98of the hub92. As made clear below, this known relationship corresponds with the known relationship of the flush port outlet56relative to the insertion end46of the access port36so as to position the groove108in fluid communication with the outlet56upon final assembly.

With continued reference toFIG. 4, the seal body76is maintained within the hub90, and is sized to contact, and seal against, the catheter70. The seal body76can assume a variety of forms and constructions, and can incorporate various features that enhance mounting within the hub90. Regardless, the seal body76exhibits at least a degree of deformability, thereby permitting sliding of the catheter70relative to the seal body76while maintaining a fluidly sealed relationship. In some embodiments, the seal body76provides a wiping-type attribute, whereby contaminants accumulated on the exterior surface of the catheter70are removed by the seal body76as the catheter70is withdrawn therethrough.

The coupler78is mountable to the hub90, and serves to lock the sheath72against the hub90as reflected inFIG. 4. Thus, the coupler78can have a variety of constructions differing from those shown, and may include one or more bores112(FIG. 3) sized to receive the pins102(FIG. 3) in some embodiments.

Connection between the adapter assembly22and the suction catheter assembly24is shown inFIG. 5A. The nose92is inserted into the access port36via the insertion end46(e.g., slip fit mounting), thereby establishing a pathway for the catheter70relative to the passageway44. With this arrangement, the distal end82of the catheter70can be distally advanced through the manifold30and into and through the respiratory port34for performing a respiratory tract suctioning procedure as described above. In this regard, and as better reflected inFIG. 5B, the valve device40provides one or more features (such as a slit120) that permits passage of the catheter70while effectuating re-sealing of the passageway44once the catheter70is withdrawn.

Returning toFIG. 5A, a clinician may periodically wish to clean or flush the catheter70, for example the distal end82, via the flush port38. In this regard, the access port36and the fitting74are configured such that upon insertion of the nose92to the position ofFIG. 5A, the circumferential groove108is aligned with the flush port outlet56. For example, and as alluded to above, a longitudinal distance between the groove108and the second end98of the hub90corresponds with a longitudinal distance between the flush port outlet56and the insertion end46of the access port36such that when the second end98is placed into abutment with the flange48of the insertion end46(i.e., the second end98has an outer dimension or diameter greater than a corresponding dimension of the passageway44at the insertion end46), the flush port outlet56and the groove108are aligned. Notably, a variety of other configurations can additionally or alternatively be employed to effectuate this aligned relationship (as well as temporarily locking the fitting74to the access port36). For example, a diameter of the passageway44can taper to a dimension less than an outer diameter of the nose92at the trailing end104at predetermined longitudinal location relative to the flush port outlet56that correlates with a longitudinal distance between the trailing end104and the groove108. Regardless, the inner surface50of the conduit42and the exterior surface106of the nose92have corresponding shapes and dimensions (e.g., corresponding longitudinal taper) such that in the assembled position ofFIG. 5A, the exterior surface106of the nose92nests against the inner surface50of the conduit42.

The aligned relationship between the flush port outlet56and the groove108establishes a fluid connection with the apertures110. More particularly, a seal-like relationship is formed between the inner surface50of the conduit42and the exterior surface106of the nose92. The groove108effectively defines a gap or spacing within this nested interface that fluidly interconnects each of the apertures110with the flush port outlet56. Thus, for example, the plurality of apertures110can include a first aperture110aand a second aperture110b. In some arrangements, at least one of the apertures110(e.g., the second aperture110bwith respect to the one representation ofFIG. 5A) is not directly aligned with the flush port outlet56. Liquid entering the flush port channel52is forced to the outlet56and then into the groove108. The groove108directs the so-delivered liquid to each of the apertures110, including ones of the apertures110that are not directly aligned with the outlet56(e.g., liquid is delivered to the second aperture110bvia the groove108). As a point of reference, with a catheter flushing procedure, the catheter70can first be withdrawn relative to the fitting74such that the distal end82is proximate the apertures110so as to better ensure that the delivered cleaning liquid interfaces with the distal end82and can be evacuated through the catheter lumen80.

In addition to forming the respiratory apparatus20, the adapter assembly22can be used in conjunction with other instruments as desired by a clinician. For example, the suction catheter assembly24can be disconnected from the access port36, and a different instrument (e.g., bronchoscope) inserted therein. Under these circumstances, the flush port38remains with the adapter assembly22, and is therefore available to perform a cleaning procedure relative to this separate instrument.

As mentioned above, the valve device40is provided to maintain a fluidly sealed relationship of the access port36, while permitting periodic insertion of an instrument therethrough. In some embodiments, the valve device40incorporates features that enhance sealing surface closure.

For example, the valve device40can include a valve body200and a valve seat structure202(referenced generally inFIG. 5B). In general terms, the valve seat structure202maintains the valve body200relative to the passageway44, with the components200,202configured in tandem to provide the enhanced sealing. Relative to final assembly within the passageway44, the valve body202can be described as having or defining a first or upstream end204and a second or downstream end206. The upstream end204is located more proximate the insertion end46of the access port36as compared to the downstream end206.

The valve body200is shown in greater detail inFIGS. 6A-6Cand includes a base210and a wall212. The wall212extends from the base210to define an internal chamber214(referenced generally inFIG. 6B), and has a dome-like shape. The valve body200can be formed from a variety of flexible, elastically deformable materials appropriate for effectuating a fluid-tight seal, such as rubber.

The base210is circular or ring-like, and defines a leading side216and a trailing side218. Relative to the final assembled position (FIG. 5A), then, the leading side216forms the upstream end204. The sides216,218are configured for engagement with corresponding features of the valve seat structure202(FIG. 5A). In this regard, and as described below, the base210is caused to asymmetrically flex or deflect in connection with engaged mounting to the valve seat structure202. In some embodiments, to enhance this desired flexation, the base210can include one or more fingers220, formed as tapered projections at or from the leading side216shown inFIGS. 6A and 6B. An arrangement and configuration of the fingers220relative to other features of the valve body200and the valve seat structure202is made clear below. In addition, and as shown inFIG. 6D, a slot222can be formed along the trailing side218, resulting in a circumferential rib224, with the slot222/rib224providing additional surface area interface with the valve seat structure202.

With continued reference toFIG. 6D, the wall212projects from the trailing side218of the base210, terminating at a tip226. The tip226defines the downstream end206(FIG. 5A) of the valve body200, and is generally closed relative to the internal chamber214. Passage through the tip226(and thus through the chamber214) is provided via a slit230(e.g., akin to the slit120ofFIG. 5B) formed through a thickness of the wall212(i.e., extending through an interior face232and an exterior face234of the wall212). As best shown inFIGS. 6B and 6C, the slit230is centered relative to the base210, and is highly linear or planar. For reasons made clear below, the optional fingers220are positioned perpendicular to a plane of the slit230as reflected inFIG. 6B.

FIG. 6Dillustrates that the slit230effectively divides the tip226into two halves, with each half forming a sealing edge240(one of which is shown inFIG. 6D) along the slit230. When subjected to a desired flexation or biasing force, the sealing edges240are forced into more intimate contact with one another, especially along the exterior face234, thereby effectuating a more complete seal. Thus, the sealing edges240can be forced apart by an instrument (not shown) being inserted through the slit230, but will readily and repeatedly return to a sealed relationship upon removal of the instrument. In some embodiments, to further promote this natural, sealed arrangement, a thickness of the wall212is elevated in a region of the slit230. For example, the wall212can be described as defining a first portion242extending from the base210, and a second portion244extending from the first portion242, with the second portion244defining the tip226. With these designations in mind, a thickness of the wall212at the tip226is greater than a thickness of the wall212along the first portion242. The elevated thickness along the slit230is further illustrated inFIG. 6Aby formation of a ridge246.

With the above construction of the valve body200in mind, the valve seat structure202can be described with initial reference toFIG. 7. The valve seat structure202is provided, in some embodiments, as part of the manifold housing30, and includes an upper circumferential surface250and a lower circumferential surface252. The upper surface250is configured to engage the leading side216of the base210, whereas the lower surface252is configured to engage the trailing side218. In this regard, one or both of the surfaces250,252incorporate features that impart a flexation or biasing force upon the base210.

In some embodiments, the upper and lower surfaces250,252are formed by separable parts of the manifold housing30, for example the first and second frame portions60,62, respectively, as mentioned above. With this in mind,FIGS. 8A-8Cshows the first frame portion60removed from a remainder of the manifold30, and illustrates the upper surface250in greater detail. More particularly, the upper surface250includes or forms one or more circumferential shoulders260each having at least one segment of increased height. For example, a first shoulder260acan be described as extending from a bottom side262to an engagement face264. A dimension of this extension defines a height of the shoulder260a. With these conventions in mind, the first shoulder260avaries in height along the circumference thereof, for example defining first and second raised segments266a,266b, and first and second lowered segments268a,268b. The raised segments266a,266bare circumferentially spaced from one another via the lowered segments268a,268b, with the raised segments266a,266bhaving an increased height as compared to the lowered segments268a,268b. As a point of reference,FIG. 8Billustrates the shoulder260atapering in height from the raised segments266a,266bto the first lowered segment268a, whereasFIG. 8Cillustrates the shoulder260aincreasing in height from the lowered segments268b,268bto the first raised segment266a. A spatial location of the raised segments266a,266brelative features of the valve body200(FIG. 7) upon final assembly is described below, clarifying biasing or flexation in the valve body200due to the existence of the raised segments266a,266b.

As a point of reference,FIGS. 8A-8Cillustrate the upper surface250as having three of the shoulders260(with each of the shoulders260having raised segments that are radially aligned with one another). Alternatively, a greater or lesser number of the shoulders260can be provided. Further, the first frame portion60can include additional features that facilitate mounting of the valve body200(FIG. 7), such as radial projections270.

The lower surface252can include similar features as shown inFIGS. 9A-9C(that otherwise illustrate a portion of the manifold30with the first frame portion60removed). The lower surface252includes or is defined by a circumferential rib280, with the rib280having a varying height. More particularly, the rib280extends from a bottom282to an engagement face284, with the distance of extension defining the height of the rib280. With this in mind, the rib280can be described as defining first and second raised segments286a,286b, and first and second lowered segments288a,288b. The raised segments286a,286bare circumferentially spaced from one another by the lowered segments288a,288b, with the raised segments286a,286bhaving an elevated height as compared to the lowered segments288a,288b. As a point of reference,FIG. 9Billustrates the rib280tapering in height from the first and second raised segments286a,286bto the first lowered segment288a. Conversely,FIG. 9Cillustrates the rib280increasing in height from the first and second lowered segments288a,288bto the first raised segment286a. A spatial location of the raised segments286a,286brelative features of the valve body200(FIG. 7) upon final assembly is described below, clarifying biasing or flexation in the valve body200due to the existence of the raised segments286a,286b. Additional features can further be incorporated that enhance the desired interface with the valve body200, for example a radial, convex undercut290formed along the raised segments286a,286b.

Final assembly of the valve device40is shown inFIGS. 10A and 10B. The valve body200is mounted to the valve seat structure202via pinched engagement of the base210between the upper and lower surfaces250,252. In this regard, the increased height features of the surfaces250,252are longitudinally aligned. For example, and with specific reference toFIG. 10A, the first raised segment266aof the upper surface250is longitudinally aligned with the first raised segment286aof the lower surface252; similarly, the second raised segments266b,286bare also longitudinally aligned. Notably, the valve body200is arranged such that the raised segments266a/286a,266b/286bare generally parallel with a plane of the slit230for reasons made clear below.

At the region of interface of the raised segments266a/286aand266b/286b, an increased compression force is imparted on to the corresponding portion of the base210(as compared to the compression force imparted on to the base210at regions corresponding with the lowered segments268a/288aand268b/288binterface illustrated inFIG. 10B). The base210, in turn, flexes in response to this asymmetrical bias, effectively transferring a “pushing” type force or bias on to the exterior face234of the wall212and a “pulling” type force or bias on to the interior face232. In other words, because the valve seat structure202imparts a non-uniform force on to the base (due to the non-uniform heights of the corresponding surfaces250,252), the transmitted forces cause the wall212to “pucker” or flex in a plane of the slit230. This effect is further enhanced by the optional fingers220; as shown, the valve body200is arranged such that the fingers220are located at the raised segment266a/286a,266b/286binterfaces, increasing the biasing or puckering force imparted on to the base210.

Due to the above-described non-uniform flexing of the base210, the opposing sealing edges240a,240bat the slit230are self-biased to a tightly sealed relationship, with the biasing being more focused at the exterior face234. In other words, relative to the plane of the view ofFIG. 10A, the biasing forces imparted on to the valve body200are parallel to a plane of the slit230. Conversely, and relative to the plane of the view ofFIG. 10B, the asymmetrical valve seat structure202does not cause or force pressure changes in a direction perpendicular to the sealing edge240ashown.

The above construction of the valve device40represents a marked improvement over previous valve configurations employed with airway access adapters. A more consistent, long-term seal is provided, yet desired insertion and withdrawal of instruments through the valve device40can occur. Notably, this same valve device construction can be employed with alternative airway access adapters that do not otherwise incorporate the closed suction catheter assembly interface features described above. Similarly, the benefits provided with the respiratory apparatus (e.g., flushing of a connected suction catheter) can be achieved with entirely different valve device constructions.

Although the present disclosure has been described with respect to preferred embodiments, workers skilled in the art will recognize that changes can be made in form and detail without departing from the spirit and scope of the present disclosure.