Respiratory apparatus
United States Patent 91 11 3,874,093 Garbe Apr. 1, 1975 RESPIRATORY APPARATUS Primary E.\&#39;aminerHarland LS. Skogquist [76] Inventor: Dietmar Rudolf Garbe, Maids Anomey Agen&#34; or FlrmaBlerman &amp; Blerman Moreton House, Maids Moreton, Buckingham, England 57] A T Flledl p 14, 1973 An anatomical model for teaching the intubation of [2 l AppL No: 397,387 the human trachea has epi glottis and tongue parts simulated by an assembly which is pivotally movable and biased into a normal position by elastic resilience of U-S- Clthe tongue part The larynx of the model is exposable [5 l l Cl. 1 through the mouth on manipulation of the tongue and {58] Field of Search 35/17 i l i pal-ts ith the blade of a laryngoscope. A primary use of the model is in teaching non-specialist References cued personnel to insert an endotracheal tube correctly in UNITED STATES PATENTS the trachea for resuscitation purposes. 2.029.682 2/1936 Squires 35/17 UX A jaw and a trachea may be movably mounted for 3.209.469 l0/l965 James 35/17 teaching appropriate procedures for cases 3,520.07] 7/1970 Abrahamson ct a1 35/17 6 Claims, 5 Drawing Figures PATENTS] APR 1 1975 SHEET 1 BF 2 RESPIRATORY APPARATUS The present invention relates to respiratory apparatus and has as an object the provision of means for facilitating the use thereof.  
  Resuscitation via an endo-traceal tube is often required in emergency situations. and an object of the present invention is to provide means whereby-some measure of experience of the requisite intubation technique can be obtained by non-specialised personnel, e.g. nursing staff, ambulance crews or general medical practitioners, without the use of actual human subjects.  
  In accordance with the present invention, there is provided an anatomical model for teaching the intubation of the human trachea said model having larynx tongue, epiglottis and mouth parts, the epiglottis and tongue parts being simulated by an assembly which is pivotally movable and biased into a normal position by elastic resilience of the tongue part so as to simulate visual exposure of the larynx by manipulation through the mouth with a laryngoscopc.  
  L&#39;sing the model, practice may be obtained in the art of exposing the larynx to view through the mouth by means of a laryngoscope. recognising the larynx and inserting an endotracheal tube for resuscitation purposes. By such practice it is possible for personnel to become sufficiently competent and confident to perform on a subject in emergency situations.  
  For realism, and to provide experience of the kind of manipulation which may be the lips, of the lips, the lip parts are admntageously formed of resiliently deformable material.  
  Additionally it is desirable to provide the model with an internal rigid lowerjavv part which is movable anteriorly, such movement sometimes being required on an actual subject.  
  A result of incorrect intubation can be intubation of the oesophagus rather than the trachea. It is desirable to provide the model with a retro-laryngeal oseophageal pathway. so that this effect can be demonstrated.  
  In practice. some trainees tend to lever the laryngoscope against the upper teeth. By incorporating an alarm device sensitive to force exerted on the teeth e.g. a switch operting a buzzer or lamp this tendency can be discouraged.  
  For best results the model may be provided with interchangeable upper dentures so that experience with different tooth configurations and distributions can be obtained Additionally or alternatively the larynx may be resiliently mounted for posterior movement under externally applied manual pressure and is preferably adjustable in its natural position. In many cases, manipulation of the larynx is required to facilitate the intubation.  
  With a model having the various preferred features hereinbefore described. a trainee may be presented with most of the difficulties which he is likely to encounter in practice and given the opportunity to learn how to modify his technique as required.  
  The following description in which reference is made to the accompanying drawings is given in order to illustrate the invention. In the drawings:  
  FIG. 1 is a side elevation of a preferred embodiment of the model.  
 FIG. 2 shows the model of FIG. 1 in cross section,  
  FIGS. 3 and 4 show details of the models on an enlarged scale, and  
  FlG. 5 shows details of the trachea and lung assembly.  
  The drawings are largely self-explanatory. The exterior of the model is moulded from rubberfof such mechanical properties as to give a realistic skin texture and a realistic response to manipulation.  
  Within the mouth is mounted an epiglottis-tongue assembly having a metal insert a pivotally mounted at b upon a pin carried by a mounting plate b. The tongue part a is a hollow rubber moulding formed with perforations to permit ingress and egress of air as it is manipulated. The epiglottis a is represented by part of the metal insert which is coated with rubber to give it a natural texture and appearance. Movement of the epiglottis is opposed by the elasticity of the tongue part, the tip of which is restrained in the region of the lower lip at c.  
 Lower teeth d are mounted upon a lowerjaw moulding 2 of rigid polyurethane. Moulding e is held only bythe exterior rubber moulding f and thus has realistic freedom of movement when manipulated.  
  Within the skull-part g of the exterior moulding f is a solid moulding h of flexible polyurethane which gives the head a realistic feel.  
  Trachea tubej of flexible material. having vocal cord formationsj&#39; (FIG. 5). passes through a short rigid tube It and connects with a bronchi bifurcation block 1. Tube k is mounted by a clamp k upon a slider p. slidably carried within a bracket q and biassed anteriorly away from the bracket by a pair of springs of which one. r is shown in H6. 4. The spacing of the clamp A&#34; from the posterior end 1) is adjustable. over a range of lcm. by a screw 1&#39;. Thus the trachea tube is movable posteriorly against spring pressure from an adjustable position.  
  Block I communicates with a pair of bronci tubes it. carried by an elastomeric moulding m, said tubes terminating in a pair of inflatable bags p which represent lungs.  
  An interchangeable set of upper teeth is resiliently mounted upon a bracket t, stiffened by a member I, and backed by a microswitch u operable to actuate a buzzer r which is energised by a battery it when teeth s are disturbed. The roof of the mouth r, together with the uvula and the throat y, are provided in the form of elastomeric mouldings shaped as shown. The lips are stiffened internally by a ring 1.  
  Moulding y has an edge which is in contact, or nearly in contact, with trachea tubej to simulate an oesophageal pathway visible posterior to the larynx when the tongue and the epiglottis are manipulated with the blade of a laryngoscope to give a straight line of sight through the mouth.  
  Training features provided by the model may be summarised as follows:  
  1. The skin is textured and mobile, and the lips are sufficiently supple to enable the operator to mould and retract them during manipulation.  
 2. The lower jaw is mobile and can be moved forward by up to 2.0 cm.  
 3. The larynx assembly may be moved anteriorly or posteriorly in relation to the spine, thereby introducing a varying degree of difficulty for the trainee operator. 4. The larynx can be depressed by downward pressure as in the human subjectdemonstrating the useful manoeuvre often used to facilitate a difficult laryngeal view, as when the larynx is lying&#39;in an anterior position.  
 5. The depression of the larynx in fact simulates Sellicks method of cricoid pressure and is pre-adjustable by spring pressure to require about 0.3Kg/cm -equal to that required to satisfactorily effect this manoeuvre in actual practice. 6. A retro-laryngeal oesophageal pathway is represented in the correct anatomical position, for demonstrating inadvertent intubation of the oesophagus. 7. The trainee is discouraged from levering the laryngoscope against the upper teeth by a buzzer alarm. 8. The tongue/epiglottis configuration provides effective simulation of the laryngoscope blade action:  
 a. to depress the tongue thus revealing the tip of the epiglottis. then b. flexing the epiglottis towards the tongue thus revealing the entrance to the trachea, vocal chords etc. 9. The bifurcation of the trachea follows an anatomical angle and allows a long endotracheal tube to find its way into the right bronchus. thus demonstrating the value of choosing a correct length of tube. 10. The upper denture is readily detachable. The degree of difficulty&#39; for the trainee can be varied by the provision of dentures with different forms. Two alter native sets are provided as standard; one with protrud ing teeth. the other a partial set.  
  I claim: 1. An anatomical model for teaching the intubation of the human trachea said model having a larynx part, mouth parts. a tongue part. an epiglottis part joined to the base of the tongue part, an anteriorly movable lower jaw part and a pivotal mounting carried by the lower jaw part and positioned adjacent the junction of the epiglottis and tongue parts, the epiglottis and tongue parts being simulated by an assembly which is pivotally movable about said pivotal mounting and biassed into a normal position by elastic resilience of the tongue part. said elastic resilience and anterior movability of the tongue part with the jaw part co-operating to simulate visual exposure of the larynx part by manipulation through the mouth parts with a laryngoscope.  
  2. A model according to claim 1 having lip parts formed of resiliently deformable material, said lip parts simulating the lips of a human mouth.  
  3. A model according to claim 1 having a formation representing a retro-laryngeal pathway in addition to the larynx part.  
  4. A model according to claim 1 having a set of interchangeable upper dentures providing a choice of upper teeth formations.  
  5. A model according to claim 1 in which the larynx is resiliently mounted for posterior movement under externally applied manual pressure.  
  6. A model according to claim 5 in which the larynx is carried by adjustable means operable to position the larynx over a range of chosen natural positions from which it is resiliently displaceable by said manual pres sure.  
  UN Fri-1E GFI ECE LIERETE&#39;FHTA&#39;EE; UEREQETIQN PAZL&#39;NT NU. 3,874,093  
 mm) r April 1, 1975 rwrjmr&#39;owsr DIETMAR RUDOLF GARBE H rs certified that error appears rrr the abo re-rderriifiedpatentand r&#39;nat said Letters Paterrr are hereby corrected as shown below;  
 Column 1, Line 29: Delete &#34;manipulation which may be the lips of the lips, the lip&#34; Insert: --manipulation which may be required of the lips, the lip Signed and Salad tr&#39;s A ttesl:  
 RUTH C. MASON C. MARSHALL DANN Arresting Officer Cammissioner of Parents and Trademarks