WO2018092150A1

WO2018092150A1 - Oral/nasal resuscitator with superior ventilating capacity

Info

Publication number: WO2018092150A1
Application number: PCT/IN2017/000131
Authority: WO
Inventors: Ananthanarayanan KALYANARAMAN; Kotak Nirav MADHUSUDAN; Ashish PATYAL
Original assignee: Kalyanaraman Ananthanarayanan; Madhusudan Kotak Nirav; Patyal Ashish
Priority date: 2016-11-18
Filing date: 2017-11-17
Publication date: 2018-05-24

Abstract

An oral/nasal resuscitator device to enable medical/paramedical personnel to provide respiratory support to the patients under anaesthesia or patients in respiratory distress. This device has a proximal end, a distal end, a dynamic cuff which rests in the pharynx and an oesophageal cuff which prevents aspiration pneumonitis.

Description

TITLE

ORAL/NASAL RESUSCITATOR WITH SUPERIOR VENTILATING CAPABILITY

FIELD OF INVENTION:

The present invention mainly discloses a device, more specifically an 'airway' device, used for respiratory support first aid and for prevention of aspiration pneumonitis in patients with respiratory difficulty, unconscious patients, patients of drowning, patients of poisoning, patients of cardiac arrest, victims of mass casualty or patients who are sedated or under anesthesia.

BACKGROUND AND PRIOR ART OF INVENTION

In medical terminology, the region from the nostrils till the vocal cords is called as the "upper respiratory tract" and the region from the vocal cords till the alveolar sacs in the lungs is called as the "lower respiratory tract"

Patients with any respiratory tract ailments, patients who are under the influence of sedation/anaesthesia and patients who are admitted in emergency departments with trauma in unconscious state require "respiratory support" in the form of Positive Pressure Ventilation (PPV)

In cases such as drowning, cardiac arrest and a stroke , the patients will not be able to maintain respiration and such situations, when occurring in a non hospital setting, the bystanders have to initiate the "expired air resuscitation" or "rescue breathing" ("mouth to mouth breathing") before qualified help arrives.

The commonest of type of respiratory support is via an endotracheal tube placed in the trachea, or by using the various periglottic devices like the Laryngeal Tube™, Combitube™, LMA™ etc which permit air to be directly pumped into the lower respiratory tract, ("Invasive Positive Pressure Ventilation") or via anatomical face masks placed on the face which aid to directly pump air/gases into the upper respiratory tract ("Noninvasive Positive Pressure Ventilation") Many different types of tracheal tubes/periglottic devices are available which are designed and suited for different specific applications:

A Tracheal Tube (aka Endotracheal Tube) mainly is a catheter that is inserted through the mouth (orotracheal) or nose (nasotracheal) wherein, its distal end is placed in the trachea via the vocal cord opening, for the primary purpose of establishing and maintaining a patient airway, to ensure that adequate exchange of oxygen, simultaneous removal of carbon dioxide and to prevent aspiration of gastric secretions into the lung. Tracheal tubes are commonly used for airway management in the settings of general anesthesia, critical care, mechanical ventilation and emergency medicine.

Mostly the nasal endotracheal intubation is a blind process (i.e the trachea is not under the vision where endotracheal tube has to be inserted) hence there are high chances that the tube enters the oesophagus particularly in an emergency situation, leading to non-ventilation of the patient hence increasing the chances of hypoxia and thereby leading to consumption of more time. Also, a blind nasal intubation requires a long learning curve and good clinical exposure.

Sometimes the nasal tracheal intubation can be performed under vision, i.e under laryngoscopy aided visualization of the vocal cords, using a Magyll Forceps to push forward the tracheal tube into the vocal cord aperture, but during this process the time for initiation of ventilation is significantly increased, hence, there are higher chances of haemodynamic disturbances due to long duration of laryngoscopy as well as high chances of injury to the oral mucosa, and other anatomical structures leading to bleeding etc.

Moreover, during nasal endotracheal intubation, blind or under vision, the tracheal tube passes through nasal and pharyngeal route which may contain infective secretions and nasal commensal bacteria viruses are transmitted to the lungs, sometimes causing lung infection.

Since endotracheal intubation is a skill with a long learning curve, only qualified medical personnel are trained to perform it. Hence its use as a rescue device for first aid in non hospital settings to deliver "rescue breath" is impractical. A tracheostomy tube is another type of tracheal tube; made up of curved metal or plastic, which is inserted into a hole made on the anterior surface of the neck (following a tracheotomy) to maintain a patient lumen. This type of tube is only used only in a select subset of patients.

Laryngeal Tubes ™ are designed to secure a patient airway during anaesthesia and cardiopulmonary resuscitation. Laryngeal Tubes are inserted orally and include a primary inflatable or elastomeric cuff disposed on its distal end for blocking the oesophagus and a secondary inflatable or elastomeric cuff intermediate to the distal and proximal ends for sealing the pharynx and there are multiple apertures present between both these cuffs which enable inflation and deflation of lungs through the glottis aperture. Airway communication is thereby established from the patient's mouth to the larynx.

Laryngeal Tube™ is a useful airway device but its use is limited to the oral route. It cannot be inserted through the nasal cavity because of its large size, hence in conditions where the mouth opening is very narrow or absent, i.e, Trismus, Submucosal fibrosis, Temporomandibular joint ankylosis, wired fractured mandibular joint etc or in cases of facial trauma where oral intubation is not possible because of fractured facial bones, or where oral intubation are contraindicated, eg: Maxillofacial trauma, mandibular fracture etc . Also in situations of space limitations in the buccal cavity, eg: any oral pathology, laryngeal tube cannot be inserted. All such situations preclude the use of laryngeal tubes.

Since the Laryngeal Tube™ has a permanently inflated pharyngeal cuff, chances of inflammation, ischemia and pressure necrosis of the pharyngeal mucosa increases if the laryngeal tube cuff exceeds the mucosal perfusion pressure (approximately 25 cm of H20) for a prolonged time period. Also the use of nitrous oxide during anesthesia increases the cuff pressure due to the diffusion of nitrous oxide inside the cuff, and this increases the chances of pharyngeal tissue ischemia/necrosis further.

In the Laryngeal Tube, even if the ventilating ports gets blocked partially, there will be severe resistance to expiration leading to air-trapping in the lungs and barotrauma (increase airway pressure in the lungs leading to the lung injury). And if complete obstruction of the ventilating ports occurs then the chances of barotraumas and hemodynamic changes (hypotension etc) increases exponentially resulting in a life threatening situations unless treated promptly. Layngeal tube is not well tolerated by conscious, semiconscious patients. Its use will require sedating the patient.

Laryngeal tube is also not very compatible with spontaneously breathing patients. Conscious patients with a laryngeal tube in situ cannot speak/communicate their symptoms.

The Combitube™ also known as the esophageal tracheal airway or esophageal tracheal double- lumen airway— is a blind insertion airway device (BIAD) used in the pre-hospital and emergency setting. Like the Laryngeal Tube, it is also inserted orally and designed to provide an airway to facilitate the mechanical ventilation of a patient in respiratory distress. It consists of a cuffed, double-lumen tube that is inserted through the patient's mouth blindly so that its distal cuffed end enters either the trachea or the esophagus and enabling tracheal ventilation irrespective of the distal end being in trachea or otherwise but similar to Laryngeal Tube. The Combitube too cannot be used in awake patients, its expiration is very delayed leading to air trapping and barotrauma if ventilated with a rapid rate, patient can not speak with the Combitube in situ and it can not be used nasally or in patients with limited mouth opening.

US Patent 9421341 B2 discloses a laryngeal tube comprising a tubular component and a nozzle having a central cavity, an anterior opening and a tongue at least partially covering the central cavity. In one example, the laryngeal tube has a first lumen to deliver gases to a patient and a fluid barrier supported by the nozzle. In other examples, the laryngeal tube may include additional lumens including a service lumen to perform a function associated with the thorax and an inflation lumen to inflate the fluid barrier.

Use of LMA™ (laryngeal mask airway) is also an alternative for the Laryngeal Tube in difficult airway and in emergency situations but it also has a lot many disadvantages. Firstly it cannot be used nasally. LMAs also cant be used in conditions where the mouth opening is very narrow or doesn't open at all, example include Trismus, Submucosal fibrosis, Temporo mandibular joint ankylosis, wired fractured mandibular joint etc or in cases of trauma to the face where oral intubation is not possible because of fractured facial bones or where oral intubation are contraindicated example include Maxillofacial trauma, mandibular fracture etc . Also the use of LMA is contraindicated in full stomach patients and in pregnant females for emergency cesarean section.

The cuff of the LMA can get irreparably damaged by the sharp ends of the teeth/permanent dentures while insertion.

In anaesthetized patients, BAILEY'S maneuver (in this technique there is insertion of the LMA after endotracheal tracheal extubation during deep anaesthesia) the chances of apnoea time increases if the LMA is not inserted correctly. Also any rube being inserted through nose (nasal laryngeal tube), is better tolerated than any tube being insert through mouth (LMA). Hence an alternative for this maneuver should be sought.

LMA insertion too requires a significant learning curve and hence its use as a resuscitator device in non-hospital settings is impractical.

Further, Laryngeal tubes and Esophageal-tracheal combitubes are incompatible with fiberopticbronchoscopy/intubation. With LMAs, fiberoptic intubation is possible but it is not very easy/time consuming.

Hence improvements are desirable which provide functionality additional to enable securing of a patient airway

OBJECTS OF THE INVENTION:

The primary object of this invention is to provide an oral/nasal resuscitator device which can be inserted through the nose or mouth to aid respiratory support.

Still another object is to provide a oral/nasal resuscitator device which can be used where the oral intubation is contraindicated or difficult especially in in anaesthetized patients. Yet another object is to provide an oral/nasal resuscitator device which can be used in cardiac arrest patient for cardio pulmonary resuscitation.

Further object is to provide an oral/nasal resuscitator device which does not cause any pressure necrosis to the pharyngeal mucosa due to the presence of the proximal dynamic inflatable cuff.

Still further object is to provide an oral/nasal resuscitator device which can be used in any age group.

Yet further object is to provide a cost effective means of oral/nasal resuscitator device as it is reusable.

Further object is to give a ventilating device which can be used either nasally or orally as the situation demands.

Further object is to provide a ventilating device which can be used as a bridge to fiberoptic intubation

Further object is to have a ventilating device which prevents aspiration of gastric contents into the lungs

Further object of this invention is to create a resuscitation device with a very minimal learning process for the operator.

Yet further object of the invention is to enable Expired Air Resuscitation (EAR) in emergency situations.

Yet further object of this invention is to provide a device which can be used not only by medical and paramedical personnel, but even by non trained bystanders in case of a calamity.

Further object is to provide a manoeuvre for the said device as disclosed in the present invention to which can be inserted simultaneously while the patient remains intubated, for an alternative mode of ventilation when the patient is about to be extubated in deep anaesthesia. BRIEF DESCRITPTION OF DRAWINGS:

Figure 1 shows a longitudinal sectional view of the oral/ nasal resuscitator.

Figure 2 shows cross sectional view of the oral/nasal resuscitator of the distal l/3^rd portion showing ventilating ports and distal oesophageal cuff

Figure 3 shows cross sectional view of the oral/nasal resuscitator of the middle 1 /3^rd portion showing dynamic cuff

Figure 4 shows cross sectional view of the upper l/3^rd portion of the oral/nasal resuscitator.

Figure 5 shows longitudinal cross section view of the oral/nasal resuscitator showing inflated dynamic cuff during inspiration.

Figure 6 shows longitudinal cross section view of the oral/nasal resuscitator showing deflated dynamic cuff during expiration.

Figure 7 shows longitudinal cross section view of the oral/nasal resuscitator within the patient during inspiration.

Figure 8 shows longitudinal cross section view of the oral/nasal resuscitator within the patient during expiration.

DETAILED DESCRIPTION OF INVENTION:

Figure 1 is a longitudinal section of the ora nasal resuscitator. It shows the different components of the apparatus which consists of tube body(l), proximal dynamic inflatable cuff(2),ventilation ports(4 and 5),distal oesophageal cuff(6),blind tip (7),universal connector(8), pilot balloon (9), inflation line(10) and nasal marking(l 1).

Further diagrams explain each component of the oral / nasal resuscitator in detail.

Figure 2 shows the tube body (1), ventilation ports(4 and 5), distal esophageal cuff(6), blind tip(7), inflation Iine(lO). The tube body (1) can be made up of plastic or silicone or PVC or rubber or any suitable material and acts as a channel for inspiration and expiration of the air / inhalation agents.

The ventilation ports (4 and 5), which lie on the anterior(4) and lateral aspects(5) of the tube, are placed in between the distal and proximal cuffs and are connected to the tube lumen for the purpose of ventilation.

The distal esophageal cuff(6) can be made up of silicone, rubber polythene or any suitable material and lies in the esophagus, hence it occludes its opening thereby preventing aspiration of gastric contents and insufflation of air in stomach during ventilation. This cuff can either be a conventional cuff which continuously stay inflated ("static" cuff), or a cuff which closely mimics the intraluminal pressure (inflates with positive pressure ventilation and deflates during exhalation, a "dynamic" cuff), or both.

The blind tip (7), is the distal end of the tube which lies in the esophagus.

The inflation line (10), can be made up of silicone, rubber or plastic and is fluidly coupled to a distal esophageal cuff (6) wherein the inflation line is located within a wall of the tube and helps in inflating the esophageal cuff (2) for occluding the esophageal opening.

Figure 3 shows the tube body (1), proximal dynamic cuff(2), inflation ports (3), inflation line(lO). The proximal Pharyngeal "Dynamic" cuff (2), can be made up of silicone, rubber, polythene or any suitable material. This dynamic cuff inflates during Positive Pressure Ventilation, preventing the leak through nose and mouth during ventilation and deflates during expiration leading to easy escape of expired gases through the nasal and oral cavity.

The two inflation channels s (3), which freely communicate between the tube's lumen and the inner part of the pharyngeal cuff, enable the pharyngeal cuff to closely mimic the pressures within the tube body, thereby enabling the inflation of the Pharyngeal dynamic cuff (2) during inspiratory phase of Positive Pressure ventilation and deflation of cuff during expiration. Figure 4 shows tube body (1), universal connector(8), pilot balloon(9), inflation line(10) and nasal markings(l 1). The 15mm standard universal connector(8), is made up of hard plastic and connects to the tube body for the ventilation purpose.

Pilot balloon (9) is made up of plastic or any suitable material and helps in inflation and deflation of the distal esophageal cuff.

The three black nasal markings (1 1) on the tube body near a standard 15-mm connector (8), indicate adequate depth of insertion when aligned with the nasal tip and help in easy orientation and repositioning.

The following four figures show the working of the apparatus as a whole.

Figure 5 shows the inflation of the proximal dynamic cuff (2) during the inspiration.

Figure 6 shows the deflation of the proximal dynamic cuff (2) during the expiration.

Figure 7 shows the oral nasal resuscitator in the patient's pharynx ,which is inserted through the nose, where the distal cuff (6) lies in the esophagus and seals it's opening and the proximal dynamic cuff (2) lies in the hypopharynx , wherein the dynamic cuff (2) inflates during inspiration and helps in sealing the hypopharyngeal cavity hence preventing collapse of the surrounding structure (like base of tounge, epiglottis , posterior pharyngeal wall ) which can occlude the trachea thereby helps in preventing the backflow of the air through the mouth or nose during the inspiration, hence maximum amount of air goes into the lung for respiration which helps in proper ventilation of the lungs.

Figure 8 shows the oral /nasal resuscitator in the patient's pharynx which is inserted through the nose, wherein the distal cuff (6) lies in the esophagus and seals it's opening and the proximal dynamic cuff lies (2) in the hypopharynx , wherein the dynamic cuff (2) deflates during expiration hence the expired gases exists through two channels one through mouth or nose and other through the tube body., therefore full expiration occurs with no residual expired gas left behind or getting trapped thereby preventing barotrauma to lungs. A single embodiment of the invention has been described herein. However, many variations could be made without departing from the spirit of invention.

In an alternative embodiment, the distal (esophageal) cuff (6) can be filled with a sponge like foam made of a suitable material which can be deflated with negative pressure and which reexpands to its original dimension when exposed to atmospheric pressure. This will create a reasonable seal of the esophageal intraluminally, thereby minimising the risk of aspiration pneumonitis even if the cuff is not inflated with positive pressure, thereby enabling the device to be kept in situ for even hours or days at a time.

All sizes are available which can be used in patients of variable age.

ADVANTAGES OF THIS INVENTION :

1. In cases of trauma to the face where oral intubation is not possible because of fractured facial bones, this oral / nasal resuscitator can be use to ventilate the patient.

2. In cases where oro tracheal intubation are contraindicated, Eg: Maxillofacial trauma, mandibular fracture etc.

3. It is very useful in cases where mouth opening is very narrow or patients with no mouth opening. Eg: Trismus, Submucosal fibrosis, Temporomandibular joint ankylosis, wired mandibular joint etc

4. The oral/ nasal resuscitator can be used in any age group including the neonates to an adult of any age.

5. It can be inserted through either nose or mouth.

6. In cases where oral intubation is difficult due to difficult airway this is an alternative way of maintaining the ventilation through nasal passage.

7. It can be used in cardiac arrest patient for cardio pulmonary resuscitation and to provide "rescue breathing" in emergency situations in non hospital settings by bystanders as a first aid. It does not require any learning/training for its use because of its ease of inserting inside the nasal passage, any para medical, non-medical person can insert it and start providing Expired air resuscitation "rescue breaths".

While giving "rescue breaths" to a victim, the bystander is exposed to the risk of ending up ingesting the oral/gastric secretions of the victim while providing mouth to mouth/mouth to face mask breaths. This risk is absent while resuscitating with tis device as this has a esophageal cuff, which prevents the vomitus form the victim soiling the face/airway of the resuscitator.

When providing Expiratory Air Resuscitation (Rescue breaths administered by blowing air from the mouth of the resuscitator through an airway device introduced into the respiratory tract of the victim) using a LMA/ Laryngeal tube or any other device, the resuscitator has to remove his mouth every time from the LMA Laryngeal tube to allow the expiration of gases from the victim's lungs, which is laborious and time consuming. Due to the unique design of this device, the resuscitator need not remove his mouth to allow for expiration when providing Expiratory Air Resuscitation though this device as the expiratory gases leave around the pharyngeal cuff directly through the mouth and not through the proximal end of the device.

Because of the dynamic inflatable cuff which inflates during inspiration and deflates during expiration, there is no constant pressure on the pharyngeal mucosa therefore negligible chances of pressurenecrosis.

The dynamic inflatable cuff helps in preventing the backflow of the air through mouth or nose during the inspiration, hence maximum amount of air goes into the lung for respiration.

The dynamic inflatable cuff gets deflated during the process of expiration hence no hindrance to the flow of expired air so no build up of pressure inside the lungs (unlike Laryngeal Tubes™ and Combitubes™

Insertion of the oral /nasal resuscitator in the presence of a tracheal tube) and subsequent tracheal extubation during deep anaesthesia, in theory, reduce airway responses, without necessitating manoeuvreing of the head and neck position to obtain a clear airway as problem associated with tracheal extubation is straining (or bucking), which may be particularly undesirable if the patient has ischaemic heart disease, asthma or an unstable neck..

There is no requirement of bite block as the instrument can't be damaged by the patient's teeth, (when it is used nasally)

This device has a inbuilt aspiration prevention mechanism.

Its very effective and economical.

Can be made available in different sizes which permit it to be used in any age group. This device is compatible with fiber optic intubation. If this device is inserted orally, fiberoptic intubation can be carried out through the nostrils. If this device is inserted through a nostril, fiberoptic intubation can be performed either through the other nostril or through the oral cavity.

Claims

We Claim:

1) An airway device for insertion into the nasal or oral cavity comprising of a cylindrical tube having a proximal end, a distal end and;

a) A universal connector which is present at the proximal end,

b) An oesophageal cuff which is characterised by an inflatable, high volume low pressure cuff and is present at or near the distal end,

c) A Cuff inflation line which comprises of an inflation port, inflation valve and pilot balloon in its proximal end;

d) A pharyngeal cuff which is characterised by an inflatable cuff present midway between the proximal end and the distal end of the tube.

2) The oesophageal cuff present at or near the distal end as claimed in claim 1, wherein the cuff closes the oesophageal lumen upon inflation.

3) The inflation line as claimed in claim 1, wherein the said line is fluidly coupled to the cuff present at the distal end and the distal portion of the inflation line is located within the wall of the tube and wherein the cuff inflation port, the inflation valve and the pilot balloon are present at the proximal end of the inflation line, the pilot balloon is in fluid continuity with the inflation line to reflect the pressure of the oesophageal cuff in real time and wherein the cuff inflation port is an adapter enabling pushing of air into the inflation line and thereby into the oesophageal cuff with the means of a syringe or any suitable instrument for inflation.

4) A cylindrical tube as claimed in claim 1 , wherein the said tube consists of multiple ventilating ports which are apertures to communicate the inner lumen of the device to the outside and are present on the anterior and lateral aspect of the tube member, in the portion between the pharyngeal and esophageal cuffs to drive air into the laryngeal inlet(glottis) and trachea during Positive Pressure Ventilation.

5) A pharyngeal cuff, as claimed in claim 1, wherein the said cuff is situated over multiple apertures which are present on the body of the tube and the said apertures communicate the inner portion of the pharyngeal cuff with the inner lumen of the cylindrical tube so as to obtain the same intraluminal pressure as that of the cylindrical tube which results in inflation of the cuff during the inspiratory phase of Positive Pressure Ventilation (PPV) and allows the cuff to get deflated during the expiratory phase of the respiratory cycle.

6) The pharyngeal cuff as claimed in claim 5, wherein the said pharyngeal cuff upon inflation, prevents the leak of air through nose and mouth, during ventilation and deflates during expiration leading to easy escape of expired gases through the nasal and oral cavity.

7) An alternate embodiment of the airway device as claimed in claim 1, wherein the oesophageal cuff comprises of a sponge or foam inside its body enabling an almost complete collapse of the cuff with negative pressure exerted using a syringe through its inflation lumen and which expands to its original shape and size when exposed to atmospheric pressure through the same lumen and wherein the said pilot balloon will not contain a valve mechanism.

8) An alternative embodiment of the oesophageal cuff as claimed in Claim 2, wherein the said cuff communicates with the lumen of the cylindrical tube in fluid communication through multiple apertures at the sides or at the distal tip of the said cylindrical tube as set forth in claim 1 and the said cuff inflates during an inspiratory phase of Positive Pressure Ventilation and gets deflated during the expiratory phase of the said Positive Pressure Ventilation and wherein the cuff closes the oesophageal cavity on inflation.

9) A further alternative embodiment of the oesophageal cuff as claimed in Claim 2, wherein the said cuff comprises of a plurality of cuffs of uniform nature or which can be a combination of permanently inflated cuffs or intermittently inflating cuffs.

10) An airway device for insertion into the nasal or oral cavity as claimed in claim 1, which can be inserted simultaneously via the nasal route as an alternative mode of ventilation when the patient is intubated orally and is under anesthesia.