Patent Application
20110290254
The present disclosure relates to a tracheal tube, and more particularly to a tracheal tube having a connector insert for rigidifying a connection and securing a cannula to the connector.
This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the present disclosure, which are described and/or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present disclosure. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.
A wide range of applications exist for artificial ventilation, which may call for the use of tubes that are inserted into a patient. Such tubes may include endotracheal tubes, tracheostomy tubes, and so forth. In the former case, the tubes are typically inserted through the mouth and into the trachea. In the latter, the tubes are often inserted into an opening formed in the neck and trachea of the patient. In both cases, the tubes may be used for artificial ventilation or for assisting patient ventilation. They are typically designed to interface with standard connectors that are located at the end of a ventilation hose assembly which itself may be connected to a ventilator.
Current designs for such tubes may allow for easy connection to an upper connector, but may have various structures, some quite complex, for conveying air between the connector and a cannula that extends into the patient. In some cases, a soft plastic or rubber is used for the connector, providing a nice seal with the interfacing ventilation assembly, although such soft materials may collapse or deform when pressed into the mating connector element. Moreover, difficulties exist in the mounting of the cannula in such devices, which must interface with the connector portion to provide the desired airflow path. The sizes of such cannulas may vary substantially, depending upon the anatomy of the patient, the age of a patient, and so forth. For example, the inner diameter of cannulas for pediatric and neonatal patients may vary between 2.5 mm and 6.5 mm. Larger sizes may be provided, but it would be desirable to have a uniform system of attachment between the cannula and the connector independent of the size.
The present invention provides a novel arrangement for a tracheal tube designed to respond to such needs. In accordance with one embodiment, a connector is provided having a generally annular body. A cannula has an upper end that is disposed in the annular body of the connector. An insert is disposed in the annular body of the connector and has a tubular lower extremity that contacts an upper end of the cannula to retain the cannula lodged within the annular body.
In a similar arrangement, a tracheal tube may include a connector that has a generally annular body with an outer surface dimensioned to a standard connector size. A cannula has an upper end that is disposed in the annular body in at contacts the inner surface of the annular body. An insert is disposed in the annular body and has a tubular lower extremity that contacts the upper end of the cannula to compress the cannula between the insert and the inner surface of the annular body to retain the cannula lodged within the annular body.
Also provided is a method for making a tracheal tube. The method includes inserting a cannula into a lower opening in an annular body of a connector. An insert is inserted into an upper opening of the annular body to expand and compress the upper end of the cannula against an inner surface of the connector to retain the cannula in the connector.
Advantages of the disclosed techniques may become apparent upon reading the following detailed description and upon reference to the drawings in which:
One or more specific embodiments of the present techniques will be described below. In an effort to provide a concise description of these embodiments, not all features of an actual implementation are described in the specification. It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions must be made to achieve the developers' specific goals, such as compliance with system-related and business-related constraints, which may vary from one implementation to another. Moreover, it should be appreciated that such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure.
In the illustrated embodiment, the cannula 14 is a hollow tube that can direct air or other ventilation gasses into and out of a patient. To conform more aptly to the patient anatomy, a curved section 20 may be provided as shown. The curved section ends in a lower or distal tip 22 which will be lodged in the patient during use. The illustrated cannula is not designed to be sealed to the patient airway, although the present design is intended to extend to cannulas having one or more inflatable sealing cuffs (not shown).
The connector 12 further includes an insert 24 which is disposed inside the connector body as described more fully below. As also described below, the insert serves to rigidify the connector body and to retain the cannula within the connector body. Moreover, the insert may assist in preventing rotation of the cannula within the connector body. An air passageway 26 is formed through the insert 24 and extends through the cannula such that, when coupled to appropriate ventilation devices, air or other gasses may be freely exchanged between the upper or proximate end of the connector and the distal end 22 of the cannula.
The cannula itself has an upper end 46 which forms a tapered upper section 48 configured to fit against the inner surface of the connector body as described below. A lower tapered section 50 also contacts and interfaces with the inner surface of the connector body to retain the cannula in place of within the connector. In the illustrated embodiment, a channel or notch 52 is formed in the upper end of the cannula that receives the protrusion 40 in the insert when the pieces are assembled within the connector. The fit of the protrusion within the channel precludes a rotational movement of a cannula within the connector. The three components will typically be formed separately. The connector and insert will typically be molded, while the cannula may be made by an extrusion process. Other processes may, of course, be employed where desired and appropriate. In a presently contemplated embodiment, the connector is made of a soft polyvinylchloride or other synthetic plastic. The soft material of the connector allows for easy gripping and a good contact fit with the mating connector part when the tube is connected to a ventilation system. The softer material also allows for comfort against the patient's neck when the device is not connected to a mating connector (e.g., of a ventilation system). The flanges may also be molded with the body of the connector, or these could be added in a separate operation. In a presently contemplated embodiment, the flanges are co-molded or over-molded with the connector body. The cannula 14 may also be made of a synthetic plastic material, such as soft polyvinylchloride, polyurethane, thermoplastic elastomers, or other synthetic plastics. The insert 24 may be made of a harder material than the connector body, such as a hard polyvinylchloride, a polycarbonate plastic, ABS, or any suitable material or a combination of materials. Where the insert is harder than the soft connector body, it provides rigidity to a connector body and resists forces that might tend to collapse the connector body, such as from mating connectors, and so forth. The more rigid structure also provides a good surface to which the cannula may be bonded, and that supports the inner diameter of the cannula.
The assembly may be performed by first inserting the insert into the cannula, then by inserting both the cannula and the insert into the connector, such that the cannula lower end extends through the connector and the cannula seats within the connector as described below. During insertion, the insert is aligned with the connector inner surface and pressed into place. In the present embodiment, the retention features of the insert cooperating with those of the connector prevent the insert from being easily removed from the connector. Although mechanical features are built into the connector and insert in the embodiment illustrated, such mechanical features may be complimented by various bonding agents and/or adhesives. In certain embodiments, the insert and connector body may be co-molded or over-molded. It should be noted that the assembly may proceed in different orders (e.g., by insertion of the cannula in the connector with or separately from the insert), depending upon the particular configuration of the components, the nature of the retaining features of each, and the type of processes used for formation and assembly (e.g., bonding, overmolding, etc.).
It should be noted that the sizes of these components may be adapted to conform to various standard sizes of tracheal tubes. For example, in tubes used for pediatric and neonatal patients, an inner diameter of the cannula may vary between 2.5 and 6.5 mm. Other sizes, could, of course, be accommodated. It should also be noted that, as shown in
