JPH07108317B2 - Tracheal tube - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a medical or veterinary endotracheal tube and a tracheostomy tube (hereinafter collectively referred to as a tracheal tube). More specifically, the present invention relates to a tracheal tube with a cuff, which is inserted into the trachea through an oral cavity, a nasal cavity, or a tracheotomy opening, connects an artificial respirator and a lung, and is used for artificial respiration.

[Conventional technology]

The cuff of the endotracheal tube with a cuff that is inserted into the trachea of a person and used for ventilation prevents vomiting from the esophagus, etc. from entering the trachea, and connects the tube to the intermittent positive pressure. It is used to keep the inner wall of the trachea and the endotracheal tube airtight so that gas can be prevented from leaking through the gap with the tracheal wall while providing sufficient ventilation when breathing. However, in the case of a conventional cuffed endotracheal tube, when connecting to an artificial respirator to manage the patient's breathing, the gas for inhalation sent from the artificial respirator when lung compliance decreases. Since it is necessary to raise the pressure several times higher than the normal pressure inside the cuff, the cuff of the endotracheal tube with a cuff that should be lightly adhered to the inner wall of the trachea at the desired pressure to maintain airtightness, Between the lung side and the pharyngeal side of the airway It deforms due to the pressure difference between the two and shifts due to positive pressure artificial respiration, and finally the airtightness of the cuff and the endotracheal wall is impaired, resulting in insufficient ventilation due to leakage of insufflation gas or movement of the endotracheal tube. It could lead to serious consequences.

As a measure to prevent this, there is a method of raising the internal pressure of the cuff to a level considerably higher than the required maximum airway pressure in advance, but if this method is performed, a constant increase in the compression pressure against the inner wall of the trachea of the cuff will be achieved. As a result, the capillaries on the inner wall of the trachea may be pressed to impede the blood flow, leaving the mucosal cells in contact with the cuff functionally impaired, and sometimes leading to necrosis. In order to solve this problem, if necessary, that is, when the intrapulmonary pressure rises, the cuff pressure is also increased, and when the intrapulmonary pressure is reduced, the cuff pressure can be reduced to the minimum necessary. Even if the inner wall of the trachea is temporarily pressed with the blood flow and the blood flow in the capillaries is blocked, the cuff pressure also decreases because the lung and airway pressures rapidly decrease during the expiratory phase, and the capillaries of the inner wall of the trachea are reduced. Based on the idea that the blood flow in blood vessels can be improved and damage to the tracheal inner wall can be prevented, a cuff-roller used by connecting to a cuffed endotracheal tube (trade name, manufactured by Respironics Inc., USA)
And breathing pressure superposition type cuff pressure adjusting device (Japanese Patent Application No. 61-29098)
And other inventions have been made.

In brief, the cuff-roller arranges a bladder (23) pressed by a spring in a small case (21) having a connection port (26) in an airtight manner, as shown in FIG. The air bag (23) is provided with a gas inlet (24) having a check valve (25) and a connection port (27) for connecting with the cuff (C) of the endotracheal tube (T). There is. When the connection port (27) and the cuff (C) are connected and gas is injected from the gas injection port (24) at the time of use, the air bag (23) communicating with the cuff (C) also expands. The spring (22) is pushed, but the pushing pressure of this spring (22) is made to be a force commensurate with the desired pressure of the cuff (C), so that the spring (22) at the desired cuff pressure is pressed. The pressing force is settled within the operation stroke of this spring (22), while the connection port (26) of the small case (21) is communicated with the airway of the endotracheal tube (T). , The air sac (2
3), the airway pressure is added to the desired cuff pressure of the endotracheal tube (T). However, this method has a problem that the price increases due to mounting of an expensive device that is disposable.

In addition, the respiration pressure superimposition type cuff pressure adjusting device is a method that makes full use of a device that adds airway pressure to the cuff pressure by using oxygen gas or compressed air in medical gas piping as a power source. Therefore, it could not be used in the absence of pressure gas.

Therefore, in order to solve the above-mentioned problem, the present applicant provides a conventional cuffed tracheal tube with a second cuff independently provided inside the cuff that does not communicate with the cuff inflation tube, and A double cuffed tracheal tube having a single or a plurality of vent holes communicating the inside of the tube with the inside of the second cuff is proposed in the tube wall portion of the tube surrounded by the above-mentioned tube (Japanese Patent Laid-Open No. 63-63). -229064, 63-229065,
Japanese Patent Application No. 62-234265).

[Problems to be Solved by the Invention]

However, the above-mentioned double-cuffed tracheal tube has a force that suppresses the cuff from the outside, contrary to the force that inflates the cuff when the airway pressure increases, so when using this to artificially breathe. The effect of preventing the tube from being pressed back against the pressure at the time of intake was not sufficiently exerted.

The present invention is to improve the above-mentioned drawbacks of the double cuffed tracheal tube, has a simple mechanism and is excellent in safety, and surely raises and lowers the cuff of the cuffed tracheal tube in synchronization with the intrapulmonary pressure. It is an object of the present invention to provide an economical tracheal tube in which the cuff pressure level which is adjusted to the minimum necessary level is always maintained and the degree of deformation and displacement of the cuff accompanying this is reduced.

[Means for solving problems]

In order to solve the above problems, the present invention provides a conventional cuffed tracheal tube with a second independent cuff that surrounds the cuff on the outer wall of the tube and that the tip side substantially coincides with the tip of the end cuff. At the same time, a mechanism is provided in which an outer wall portion of the tube surrounded by the second cuff is provided with one or a plurality of ventilation holes that pass through the inside of the tube and the second cuff.

[Operation of the invention]

Since the tracheal tube of the present invention is configured as described above, it will be described with reference to FIG. 1. An inner cuff (hereinafter referred to as a cuff) located near the tip of the endotracheal tube (1) inserted into the trachea The airway sealing cuff (5) is inflated when gas is injected from the cuff inflation tube (6) to the outer cuff of the trachea inner wall (7) (hereinafter referred to as the tracheal pressure interlocking inflation cuff) (4). And has a function of sealing between the trachea and the endotracheal tube (1). On the other hand, the intratracheal pressure motion expansion cuff (4) communicates with the gas passage (2) in the airway, and therefore expands and contracts according to the increase and decrease of the gas pressure in the gas passage (2). That is, when the gas pressure in the gas passage (2) becomes large, the gas in the gas passage (2) flows in from the airway pressure introduction port (3), so that the trachea pressure interlocking expansion cuff (4) expands. The tracheal inner wall (7) of the patient or the like is pressed with a pressure corresponding to the airway pressure at that time. Therefore, the position of the cuff does not shift due to the increased intratracheal pressure.

〔Example〕

FIG. 1 is a view showing a tracheal tube according to a preferred embodiment of the present invention.

The tracheal tube of the present invention is a tracheal tube with a cuff which is inserted and installed in the trachea of a patient or the like for the purpose of managing breathing, and an endotracheal tube as shown in FIG. 1 is a preferred example thereof. is there. As shown in FIG. 1, a tracheal sealing cuff (5) is installed in the form of an air sac on the outer periphery of the endotracheal tube (1) in the vicinity of the distal end, and the tracheal sealing cuff (5) is further expanded with an airway pressure interlocking expansion cuff (4). It is surrounded so that it is airtightly wrapped from the outside. Then, the tracheal sealing cuff (5) is supplied with gas or discharged through a cuff inflation tube connecting passageway (8) formed on the wall surface of the endotracheal tube (1) to allow tracheal sealing cuff (5). A cuff inflation tube (6) for inflating or reducing 5) is connected, and communicates with an air chamber (9) formed by the cuff (5) and the outer wall of the tracheal tube (1). There is. On the other hand, the inflation cuff (4) interlocking with the airway is provided in the shape of an air bag on the outer wall of the tracheal tube (1) so as to surround the cuff (5) for sealing the airway, and the cuff (4), the cuff (5) and the trachea. The space (11) formed by the outer wall of the tube (1) communicates with the gas passage (2) in the airway through the vent hole formed in the outer wall of the tube (1), that is, the airway pressure introduction port (3). When the airway pressure increases, the gas in the airway is introduced into the space (11) through the introduction port (3), the airway pressure interlocking expansion cuff (4) inflates, and presses the tracheal inner wall (7). It is like this.

The endotracheal tube (1) is made of a flexible resin such as soft vinyl chloride resin, silicone rubber, or polyurethane, and has a certain degree of flexibility and elasticity. Then, in the endotracheal tube (1), the gas passage (2) in the airway having a large inner diameter, which is open at both ends, is closed at the tip side (patient side) and opened at an appropriate portion on the air end side (operator side). , A cuff inflation tube connection passage (8) having a small inner diameter is formed, and a bevel is formed at the tip of the endotracheal tube (1) for easy insertion into the trachea, and the endotracheal tube (1) is formed.
Vents that communicate the inside and outside of the wall of the endotracheal tube (1) with the portion surrounded by the airway pressure interlocking expansion cuff (5) excluding the portion surrounded by the tracheal sealing cuff (5) near the distal end of the One or more small airway pressure inlets (3) are provided. The cuff inflation tube connection passageway (8) communicates with the air chamber (9) of the tracheal sealing cuff (5) through a hole or groove formed in the outer wall of the tube (1) at the tip side. .

The inflation cuff (4) interlocking with the airway pressure and the cuff (5) for tracheal sealing are formed of a flexible resin such as soft vinyl chloride resin, silicone rubber, or polyurethane into a cylindrical shape.
It is arranged and formed on the outer circumference of the endotracheal tube (1) so as to form an air bag-like thin film when inflated. The outer airway pressure interlocking expansion cuff (4) communicates with the airway gas passage (2) through the airway pressure inlet (3), and the airway pressure is higher than the airway pressure when the tracheal tube (1) is inserted. When it becomes large, it has a function of expanding and compressing the tracheal wall to seal between the trachea and the endotracheal tube (1).

The cuff inflation tube (6) is made of a flexible resin such as soft vinyl chloride, silicone rubber, polyurethane, or polyethylene with a small diameter, and one end thereof is airtightly bonded and fixed to the cuff inflation tube connection passage (8). It The other end of the cuff inflation tube (6) is a connection end with a gas supply means (not shown) and is formed in a shape connectable to the tip of a syringe. A pilot balloon (10) is provided to confirm the expanded state of the sealing cuff (5) from the outside.

Next, an example of use of the tracheal tube of the present invention will be described.

If necessary, gas is injected and discharged by the cuff inflation tube (6) to test the airtightness of the tracheal sealing cuff (5), and then the gas in the cuff is discharged and deflated, and then for the trachea The tube is inserted and fixed at a desired position in the trachea of a patient or the like. Then, using the cuff inflation tube (6), gas is injected until the compression pressure of the tracheal sealing cuff (6) against the inner wall of the trachea reaches a desired pressure, and then the cuff inflation tube (6) is closed, The proximal end of the endotracheal tube (1) is connected to a respirator or the like (not shown), and respiratory control of the patient or the like is performed by intermittent positive pressure artificial respiration or the like. In this case, the absorption pattern corresponding to the inspiration phase in natural respiration corresponds to the operation of mechanically pressurizing the respiratory gas and pushing it into the lungs in the pressurized respiration. Therefore, at this time, naturally, the intrapulmonary pressure and the gas pressure in the airway gas passageway (2) of the endotracheal tube (1) communicating with this increase.

When the gas pressure in the airway gas passageway (2) rises and the airway pressure becomes higher than the tracheal pressure outside the inflation cuff (4) interlocking with the airway pressure, that is, the pressure that pushes the inflation cuff (4) from the outside, the airway pressure is introduced. Gas in the airway flows in from the mouth (3), and the inflatable cuff (4) interlocking with the airway pressure presses the tracheal wall with the pressure of the gas in the airway.

Thus, the compression pressure against the inner wall of the trachea (7) of the patient is equal to the initial set pressure of the tracheal sealing cuff (5) when the pressure inside the airway gas passage (2) is low, and When the pressure inside) is greater than the airway pressure outside the inflation cuff (4), the airway pressure is applied to the tracheal wall at that time, and the airway pressure is synchronized with positive pressure breathing. Since the compression force of the trachea by the inflation cuff (4) changes, the endotracheal tube (1) is not displaced from the tracheal wall and is maintained in a predetermined position.

〔The invention's effect〕

As is clear from what has been described above, the tracheal tube of the present invention has the following advantages.

(1) Since the mechanism is simple, the number of constituent members is small, and no special power source is required, which is economical.

(2) In the conventional cuff, a low-pressure and large-capacity one is preferable because it softly presses the inner wall of the trachea, but the airway pressure on the lung side pushes the cuff membrane from the lung side in the trachea to deform the cuff and increase the cuff pressure. Therefore, the cuff is distorted and pushed after each pressurization breath, so that the friction easily damages the ciliary mucosa of the inner wall of the trachea, and the endotracheal tube also easily moves, and it is connected to the endotracheal tube. Although there is a drawback in that the breathing tube forming the breathing circuit and the connecting portion of the connector are constantly moved and easily come off, such an accident can be prevented by using the endotracheal tube of the present invention.

[Brief description of drawings]

FIG. 1 is an explanatory view showing an embodiment of the present invention, and FIG. 2 is an explanatory view of a conventional example. [Explanation of main symbols] 1: Endotracheal tube 2: Airway gas passage 3: Airway pressure introduction port 4: Airway pressure interlocking expansion cuff 5: Tracheal seal cuff 6: Cuff inflation tube 8: Cuff inflation tube connection aisle

Claims (1)

[Claims] 1. A substantially cylindrical flexible thin film is disposed near the tip of the tube so as to surround the outer circumference of the tube, and both ends of the thin film are airtightly attached to the outer circumference of the tube to form a cuff. In addition, in a tracheal tube connected with a cuff inflation tube for injecting and discharging gas into the outer cuff to arbitrarily inflate the cuff, the outer wall of the tube surrounds the cuff and a tip is provided. A second independent cuff is provided so that its side substantially coincides with the tip of the cuff, and the inside of the tube and the second cuff are communicated with the sensitive wall portion of the tube surrounded by the second cuff. A tracheal tube having one or more ventilation holes.