Background of the Invention
Field of the Invention
The present invention relates to a device for laryngeal airway respiration and related features and devices.
Discussion of the background information
An endotracheal tube is the usual way to maintain an airway of an unconscious patient during general anesthesia.
Alternatively, an oro- or naso-pharyngeal airways are used in conjunction with a face mask.
Using the endotracheal tube technique there is a risk that the laryngoscope may cause damage to the teeth and that the tube may injure the vocal cords or the larynx. There is also a risk of accidental esophageal intubation or of the right or left main bronchus.
Using the face mask technique there is a risk of gastric content being aspirated into the lungs.
Brain (U.S. Patent No. 4509514) described an artificial airway device in the form of a laryngeal mask airway. This laryngeal mask airway comprises a tube opening into the interior of a mask portion, whose periphery, which may be inflatable, is adapted to seal around the inlet of the larynx. This device is very expensive to manufacture, and is used even more than 500 times per each device with the risk of cross-infection. It also does not guarantee against a reflux of gastric content into the trachea through an unsealed portion of the laryngeal mask.
Greenberg (U.S. Patent No. 5443063) described a cuffed oro-pharyngeal airway as a less cumbersome alternative to face mask/oral airway technique for maintenance of general anesthesia. The airway includes an elongated tube having a length such that the proximal end is adapted to be disposed adjacent to but outside the oral cavity of the patient and the distal end is adapted to be disposed in the lower larynx of the patient, above the epiglottis. An inelastic, inflatable cuff is mounted to the tube adjacent the distal end. On inflation, the inflatable cuff displaces the soft palate against the nasopharynx to seal-off the nasal passages and defines a seal between the tube and the pharyngeal wall. However, this device does not guarantee against aspiration of gastric contents into the lungs through an unsealed part of the pharynx.
Ozaki (U.S. Patent No. 4334534) and Donmichael (U.S. Patent No. 4497318) described two versions of emergency airway management device and esophageal obturator airway.
Ozakis device is composed of three tubes : The outer tube, an inner tube and an air passageway for inflating an inflatable cuff. The outer tube has a cluster of side air ports in its wall located generally midway between the ends of the tube. A face mask is placed over the face of the patient to stop air leakage while the patient is being ventilated via the air ports.
Donmichaels device is an elongated conduit configured for insertion into the esophagus; having an expandable element at the distal end to seal the stomach of a patient from the lungs; having a series of openings located so as to enable air to flow, having a face mask to prevent air leakage while ventilating the patient.
Summary of the Invention
It is one of the objects of the present invention to overcome the limitations and drawbacks of the prior art applicators for laryngeal airway, and to provide a device that considerably simplifies the procedure.
The present invention addresses the shortcomings associated with the prior art devices, and provides a solution which is straightforward.
The present invention is composed of an elongated tube approximately 34 cm long, made of plastic. The internal diameter is approximately 7.5 mm and the external diameter 10.2 mm. The tube has a concave surface on one side of its sides, as well as a convex surface at the opposite side.
The tube is flexible, elongated conduit with an expandable cuff at its distal end, starting approximately 2 cm from the closed round end, and ending approximately 7 cm from the closed round end.
The proximal end is connected to an adapter which enables it to be connected to an elongated tube of a respiratory machine.
At approximately 3 cm from the proximal end of the expandable cuff at the concave surface of the tube there is an opening at the tube of approximately 10 cm long and 0.8 cm width, ending approximately 13 cm from the proximal end of the tube.
A small tube of approximately 1 mm width is attached at the outer surface of the convex side of the tube and is connected to the expandable cuff for its inflation and deflation. At its proximal end the cuffs tube is connected to the cuffs indicator and adapter for a syringe.
At the concave side of the tube, at the proximal end, there is a marking that indicates the middle line of the opening located at the concave side of the tube, starting approximately 13 cm from that marking.
The present invention includes also other tube diameters, for example, from 4 French gauge to 9 French gauge and more. The other components like the cuff and the opening are also changed accordingly.
The present invention also includes an oro-pharyngeal airway that preserves the tube from closure by the teeth, and a transparent tape to close the oral as well as the nasal orifices, leaving only the tube extending from the patients mouth, and preventing air leakage.
The practice of the present invention is as follows :
After putting the patient asleep by general anesthesia the tube is inserted into the patients mouth and into the patients esophagus. The approximate lips-esophagus length should be measured, using the marks at the tube, in each patient before inserting the tube, by holding the tube along the outside mouth-neck surface of the patient.
After inserting the tube into the esophagus the cuff is inflated and sealing any gastric content from reaching the pharynx.
The tube is inserted in the usual way common to everyone skilled with the art while the concave side is at the tongue-epiglottis-vocal cords surface.
Then the oro-pharyngeal airway is inserted, and the tube is attached to its place by a transparent tape which close also every part of the lips, leaving only the tube extending from the mouth.
The marking at the proximal end of the tube indicates that the concave side of the tube is at the vocal cords surface.
Then a transparent tape closes also the nasal orifices in order to avoid any air leak from the mouth or the nose.
The patient can then be ventilated or breath spontaneously under general anesthesia.
At the end of the general anesthesia the patient is awakened, the cuff is inflated and the tube is taken out from its place.
The present invention avoids inserting the tube into the trachea, causing damage to the vocal cords, providing a route for lung infection, or avoiding damage to teeth.
The present invention avoids an inflated cuff at the laryngeal area which may cause tissue injury with blood pooling into the trachea and lungs.
The present invention avoids aspiration of gastric contents into the lungs by sealing the esophagus by an expandable cuff.
The present invention uses a very simple material used currently for disposable endotracheal tubes which makes its manufacturing very cheap, so allowing its use as a disposable device, and not as a reusable device like the expensive laryngeal mask airway, avoiding the risk of cross-infection.
Detailed description of the preferred embodiments
The particulars shown herein are by way of example and for purposes of illustrative discussion of the preferred embodiments of the present invention only and are presented in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the invention. In this regard, no attempt is made to show structural details of the invention in more detail than is necessary for the fundamental understanding of the invention, the description taken with the drawings making apparent to those skilled in the art how the several forms of the invention may be embodied in practice.
Fig. 1 shows the present invention (Eldor laryngeal airway): The closed distal tip 1, the cuff 2, the opening at the concave side 3, the cuffs tube 4, and the cuffs indicator and syringe adapter 5, the proximal end of the tube 6, and the tube adapter 7.
According to the present invention (but not limited to these lengths) the opening 3 length is 10 cm and width - 0.8 cm. The cuff 2 starts at 3 cm from the distal closed end 1 and ends at 7 cm from this closed end 1.
The opening 3 starts at 13 cm from the proximal end 6 and ends at 23 cm from the proximal end 6.
The marking 8 at the proximal end 6 indicates the middle line of the opening 3.
There are markings 9 every 1 cm of the tube for an exact knowledge about how much the tube should be inserted in order to avoid misplacement.
What is not shown in Fig. 1 is the oro-pharyngeal airway as well as the transparent tapes that close the oral and the nasal orifices, as well as the elongated tube connecting the Eldor laryngeal airway to the respiratory machine, and the respiratory machine itself.
It is noted that the foregoing examples have been provided merely for the purpose of explanation and are in no way to be construed as limiting of the present invention. While the invention has been described with reference to a preferred embodiment, it is understood that the words which have been used herein are words of description and illustration, rather than words of limitation. Changes may be made, with the purview of the appended claims, as presently stated and as amended, without departing from the scope and spirit of the invention in its aspects. Although the invention has been described herein with reference to particular means, materials and embodiments, the invention is not intended to be limited to the particulars disclosed herein; rather, the invention extends to all functionally equivalent structures, methods and uses, such as are within the scope of the appended claims.