DE1766155A1 - Endotracheal anesthetic catheter - Google Patents

Description

Dipl.-Ing. R. H. Bahr

Dipl.-Ing. W. Herrmann-Trentepohl Telephone:

Telex 08 229653

PATENT LAWYERS -

Ι "Π ■ · Munich 13. dßß tfft

Alter St. Georgsplatz i / l I Telephone: Manchen 35242 · _s Telex 05 24 562

Post delivery requested to 469 Herne, PO Box

File no. _A ^ 9 _ß 63 Ηβ / Pa Please state in the answer

JORGE ALBERTO MILLET PUIG, Sarmiento 2336, Castelar,

Buenos Aires Province, Argentina %

Endotracheal anesthesia catheter

The invention relates to an endotracheal catheter for ventilation of the lungs during operations and also for longer use.

To facilitate ventilation of the lungs and, under certain circumstances, to perform a number of surgical steps To be able to perform, it is necessary to insert a tube or cannula into the windpipe. This is special necessary when breathing becomes difficult or paralysis occurs, as for example in certain cases Diseases such as polio, traumatic disorders of the cranium or thorax or during operations.

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There are two ways of introducing the tube or the cannula, depending on the "particular situation of the case." various options are available, namely the tracheal incision and the endotracheal introduction. To the Performing the first option requires an operation, which is the direct connection of the interior the trachea aims with the outside atmosphere, and for that purpose at the bottom of the throat An incision is made which extends to the inner cartilage layer of the trachea wall, making a tube can be introduced. The introduction can take place for a short time or for a longer period of time. Is this operation Once this has been done, the gases entering or exiting the lungs need to be carried out. the air does not take the detour via the so-called upper respiratory tract (the upper part of the windpipe, the larynx and dog or nose). ~ "~ ~~

The endotracheal insertion, on the other hand, is bloodless and can be performed with the help of several known techniques and various auxiliary devices (larynx mirror or bronchoscope). The tube is inserted through the upper respiratory tract (mouth or nose) (larynx and windpipe) without making an incision. The above catheter is used in this method.

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Although sometimes between the cannula and tube when used in the field of the subject matter of the application Difference is made, these terms are synonymous. Some professionals also use the term catheter.

It may be necessary with the two possible ventilation methods (tracheal incision and endotracheal insertion) be to provide a seal between the endotracheal catheter and the inside of the trachea to allow two- ™ lei to achieve: On the one hand, the respiratory organs should be separated from the esophagus, for example in dysphagia, to avoid breathing in secretions, stomach contents, and the like; on the other hand should thereby artificial ventilation, either by generating successive pressure surges or by alternation can be made possible by overpressure and underpressure.

To realize this seal, Ehdotracheal- Λ have consistently catheter which is arranged in the vicinity of its lower end cuff that can be inflated once s.ie is put in place.

While there are advantages to using these known cuffed catheters, there are nonetheless a number of disadvantages which can have very serious or even fatal consequences for the patient.

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J. Mck. Watts comments on this in his article "The modern implementation of the tracheal test committee ", the in the British Journal of Surgery 50ι 954-975 »1963 was published and for which he dan 1962 in England Moynihan-Preia received.

"The main problem with using an inflatable cuff in the windpipe is its slope» causing fire by pressure on the mucous membranes i;

to take effect (Page 969) "·

To avoid this dangerous complication, suggest he, along with other professionals, made the cuff inflate as little as possible and keep it several minutes

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to collapse for an hour.

In another chapter of his article, under the heading ^M The difficulties of the trachea cut, he mentions "in connection with" difficulties that may arise during an incision in the trachea

"Five Effects of Pressure from Tracheal Sonitt- ι

Cannula

c) An illumination of the inflated man

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BATH ORIGINAL.

cuff pressure exerted on the inner wall of the trachea.

• It is vital when using inflated cuffs in the windpipe for formation to avoid fire on the tracheal mucosa. The procedures used have already been described been. Beaver reported the lack of pressure-related information in 1961 Complications from using inflated cuffs, our experience in using them The James catheter, however, was not so lucky. This catheter was used in 19 cases during the period used between 1953 and 1960; however, only four patients had the trachea after removal of the catheter examined. Of the four trachea examined, two had extensive elderly and younger tracheal wall ulcers at the site of the cuff. In another it developed ♦ a serious constriction of the trachea at the point where the cuff is placed, and this patient now has a permanent tracheal incision and has to be regular Widen the trachea at intervals.

■ ·

Kürzlioh two more air tubes after the application of James catheter were investigated at autopsy. ' One found a younger wall

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ulcer, the other had a circumferential narrowing of the trachea at the place of the cuff. ^M.

From the above it can be seen that the known Catheters with inflatable cuffs required an expansion of the cuff as soon as the catheter was inserted was inserted into the trachea to attach the catheter and the upper and lower parts of the trachea to separate from each other.

This spreading was achieved by directly inflating the cuff using a device connected to the cuff Air supply pipe causes. The inflated cuff caused the damage described above.

The cuff must be inflated in such a way that the pressure prevailing in it is greater than the greatest endotracheal pressure which the patient can generate and which corresponds to the highest pressure level. If this instruction is not followed with known catheters, then the maximum endotracheal pressure would compress and reduce the inflated cuff and this would impair the sealing attachment of the catheter in the trachea. The pressure built up in the cuff must therefore necessarily be so great that it prevents the blood circulation through the

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Tissue of the windpipe on which the cuff rests is interrupted, thereby causing the damage described above evokes.

In an attempt to avoid the said disadvantages of the known catheter on each of any possible manner, has been proposed up to the bridge in the cuff at regular intervals and to decongest Las λ sen to in this way the circulation of blood through the collar to allow surrounding tissue temporarily. However, if these pressure fluctuations are to be avoided during an operation, then a highly qualified specialist is necessary for this purpose, since the catheter can be moved out of its position in the event that the pressure drops too much and clear the way for the secretion that has accumulated on both sides of the cuff which could make the patient's breathing slower. ^

Obviously, before every pressure drop, the one on the Cuff accumulated secretion can be aspirated.

It has also been proposed to use catheters with two consecutive cuffs so that successive pressure surges can occur in different parts of each cuff. But is also in

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In this case, a specialist is required to carry out the work and the practical use of these two-cuff catheters has not shown good results because that catheter piece surrounded by the two cuffs, air tube occlusion and other inconveniences can pull itself. The secretions that collect between the two cuffs can also be difficult and difficult sometimes not removed at all, with the same difficulties as mentioned above *

The present invention is based on the idea of providing a catheter with a cuff which can hold the catheter in its correct position, but still allow blood to circulate through the cuff surrounding tissue allows and not for a longer period than the transition period between. breathe in and exhalation ^ interrupts with every breath. In this way normal conditions are maintained in the tissue and ulcer formation or any other kind of health impairment mentioned. This task is thereby solved that one makes use of the change in pressure caused by the patient's breathing, the moment of the lowest endotracheal pressure being the reference value serves to build up a necessary minimum pressure in the special cuff according to the invention in order to achieve the in the

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Trachea to hold the inserted catheter in place. In the same way, inhalation is used to increase the pressure in the cuff, as will be explained later. A massage effect is thus exerted on the corresponding vessels and a complete seal is achieved between the two parts of the trachea separated by the cuff. , Ä

In particular, the invention relates to an endotracheal catheter for pulmonary ventilation, which is both can be used during surgical operations as well as for longer periods of time. The endotracheal catheter ~ has ~ eln ™ at both ends "open catheter tube, a sleeve which surrounds a pipe section located near one end of the pipe and which is attached to the Pipe are fastened gas-tight at a distance from each other, the sleeve with the pipe section a chamber forms. An additional air supply line is connected to this cuff. The invention characterizes in that at least a part of the catheter tube section is surrounded by an inflatable bellows is, which divides the chamber into two airtight compartments, namely an outer and an inner, wherein the catheter tube section has at least one access opening

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to the inner compartment.

In a preferred embodiment of the invention, the catheter tube has more than one access opening to the have inner compartment, the openings preferential ' are enlarged in the longitudinal direction to avoid clogging and to facilitate cleaning of the device.

The edges of the outer cuff are preferably attached to the catheter tube in the same location as the edges of the inner cuff.

The air supply line can be arranged outside or inside the catheter tube. The distal end of the air supply line is preferably provided with a ball, which is known under the name "pilot" and from which the surgeon or his assistant can easily read whether the outer cuff is under pressure.

The invention is further explained using an exemplary embodiment. In the drawings is:

Fig. 1 is a partially sectioned schematic of an image inserted in a trachea erfindungegemäßen Endotrachealkathetere; -

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Fig. 2 is a diagram of the cuff pressure of a known one Endotracheal catheter which does not have the outer sleeve of the subject of the application;

Figure 3 is a diagram of cuff pressures for an inventive device Endotracheal catheter.

In Fig. 1, the reference numeral 1 denotes a schematically illustrated human trachea. The lower end of the trachea 1, also shown, divides into branches 2 and 3, which lead to the left and right lungs. As is known to those of ordinary skill in the art, an endotracheal catheter is inserted into the patient's trachea so that the lower end of the catheter is near the branches 2 and 3 of the tracheal branches prior to performing an operation. In the illustrated embodiment of the endotracheal catheter according to the invention, this consists of a catheter tube 4 with a lower end 4 ^f , which is arranged in the vicinity of the branches 2 and 3. The upper end of the catheter tube is not shown since it is not necessary to explain the invention, but it is also open, and it can be provided with additional devices.

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The pipe section adjacent to the lower pipe end 4 * of the catheter tube 4, which bears the reference number 5, is surrounded by an outer sleeve 6 with a linear upper edge 7 and a lower edge 8, both of which are reinforced and at a distance from the pipe section 5 are attached to each other on the catheter tube 4 in a gas-tight manner. The outer sleeve 6 delimits together with the Outside of the pipe section 5 a chamber which, as will be explained later, is divided into two compartments is.

Most of the known endotracheal catheters have so far been constructed in exactly the same way, but the interior of the pipe section 5 is not connected to the chamber formed by the outer sleeve 6. This outer cuff 6 is connected to an additional air supply line 9 -y- ^ eres outer-end-butt-BeiBpfei can be connected to the already mentioned "pilot" ball 10. Such a device would be constructed in exactly the same way as known devices without adding the further parts to be described and, in order to fix the endotracheal catheter, require the supply of an amount of air through the air supply line 9 until the cuff anchors the catheter so firmly in the trachea that it would even momentary excess pressures caused by the patient's cough

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would withstand. As is known, the amount of air to be supplied to the cuff is so large that the Outer cuff 6 is pressed against the windpipe 1, the blood circulation in the lying in the pressure zone Tissue is tied.

According to the invention, the pipe section 5 of the catheter pipe 4 has at least one opening, and in the embodiment shown, two elongated openings 11.

The section in which these openings 11 are located is furthermore enclosed in a gas-tight manner by an inner sleeve 12, which divides the aforementioned chamber into an outer compartment 13 and divides an inner compartment H, both of which are separated from one another in a gas-tight manner.

—So — are — in — the shown embodiment, the edges of the Inner sleeve 12 also gas-tight at the edges 7 and 8 attached.

Obviously the inner cuff might as well have their own, remote from the edges 7 and 8 attachment points for their edges that are closer to the Openings 11 are.

The edges 7 and 8 of the embodiment shown could be

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furthermore either firmly connected to the pipe section 5 » or be clamped to it resiliently to form an airtight collar. The spring-loaded collar are preferred because they allow easier cleaning of the catheter, i. H. because outer and inner cuff 6 and 12 can easily be removed from the catheter tube 4.

This should be pointed out before explaining the handling of the endotracheal catheter according to the invention

be that some of the explanations auek the breathing process relate.

The entry and exit of gases into or out of the alveoli depends on the change in internal pressure the lungs in relation to the external pressure of the room.

With natural or spontaneous breathing, the entry of the gases (inhalation) into the lungs goes on in such a way that through the thorax enlargement caused by the contraction of the respiratory muscles creates a negative pressure in the lungs. By relaxing these muscles, the thoracic volume decreases in turn, compressing the lungs and the internal pressure rises as a result, which forces the gases out of the lungs again (exhalation).

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If for any reason (except "upper airway obstruction") in the normal rhythm When there is a change in exhalation and inhalation, there is a shortage of breath, which becomes greater the more the Breathing is decreased.

It is generally believed that if the

Respiratory system no longer λ after 3 minutes

Repairable brain damage occurs sooner or later, but certainly within minutes lead to death.

In order to prevent such emergencies, the causes and the available devices are taken into account Use devices that change room pressure (such as oxygen devices or iron lungs) or endotracheal catheters (mechanical ventilators), - which work by supplying air or other gases.

Depending on the device used, the pressure changes in the trachea take place in the same direction (oxygen devices and iron lungs) or in opposite directions (mechanical ventilators) with natural breathing.

If a known catheter similar to the endotracheal catheter according to the invention is used, but this is not

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the inner sleeve 12 and the openings 11, the cuff corresponding to the outer cuff 6 is inflated through the air supply line 9 to such an extent that until the cuff has become large enough to exert pressure on the surrounding tissue, large enough to be able to continually, including cases where momentary overpressure occurs (cough) to seal the windpipe.

In FIG. 2, in which the pressures are plotted on the ordinate y and the time on the abscissa χ, the curve R represents the patient's breathing processes, in particular the curvature Rj denotes the inhalation which reaches its maximum at M and from there falls along the curve R "according to exhalation, whereupon it reaches its end position corresponding to the termination of the breathing process in the vicinity of atmospheric pressure. In order to fix the cuff of known catheters in the trachea, it is necessary to inflate the cuff to such an extent that a constant pressure is created which is greater than the maximum M and which is represented by the horizontal line F.

In contrast, in the subject of the application, in which, as can be seen from FIG. 3, the ordinate y, the abscissa χ and the curve R correspond to the values in FIG

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the curve R also shows the changes in the pressure in the trachea, these pressures are released onto the inner compartment 14 (Pig. 2) through the openings 11. transferred, wherein the dimension of the inner sleeve 12 is increased and decreased depending on the pressure change according to curve R. For anchoring of the catheter tube in the trachea must ä be blown into the outer compartment 13 through the supply line 9 air, until a final pressure is reached, the plus that produced in the inner compartment 14 pressure is composed of the correct pressure in the outer compartment 13, which is large enough during the exhalation process to hold the catheter tube firmly and sealingly in the trachea. This pressure is given by the distance A in Pig. 3 designated. Because the chest pressure rises, and with it that prevailing in the trachea during inhalation

Pressure also takes the place through — they. Li never P * , i n Eig, ^ ge ^

denoted pressure corresponding to line P in Fig. 2, ± x. to. In this way the resulting pressure is in the cuff is always the same or only slightly higher than the pressure in the windpipe.

It follows that a slight overpressure in the outer compartment 13 is sufficient to by a low pressure against the Tracheal wall to effect a seal during the main part of the breathing process, as this pressure is automatic

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every time the pressure in the windpipe increases, whereby the seal is maintained.

To give a practical example, the pressure generated in the course of a breathing process can be between plus 200 and ;, fluctuate minus 40 mm water column. The previously known endotracheal catheters, which only have one cuff, must therefore be inflated to a pressure of at least 200 mm water column in order to achieve a gas-tight fit reach.

In contrast, in the endotracheal catheter according to the invention, the outer compartment 13 only has to be inflated to a pressure which is sufficient to achieve a seal between the inner wall of the trachea and the outer wall of the sleeve when the pressure has dropped to minus 40 mm water column in the course of a breathing cycle .

During the increase in the pressure in the windpipe, which would lead to the fact that the outer cuff 6 would be compressed if there was not a sufficiently high pressure in it, this pressure is automatically increased by the additional pressure created by the patient himself by inflating the inner compartment 14 is generated.

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The pressure exerted on the tracheal wall by the outer cuff is therefore only significantly increased if when the pressure maximum is reached in the course of the breathing process.

Various embodiments are possible within the scope of the invention. So can to make a rubbing contact of the catheter tube 4 in the part with the tracheal tissue located above the outer cuff 6, f the outer sleeve 6 and optionally also the inner sleeve 12 are extended so that they are in the cover substantially the entire length of the catheter tube part which is inserted into the trachea.

Another possibility of avoiding frictional contact with the trachea wall would be to attach two bodies, each consisting of an inner and an outer sleeve, at a distance from each other, with one in μ of the tracheal branches 2 and 3, the other near the upper open end the catheter tube would have to be attached.

This latter arrangement has not yet been tried, so that some of those already described may not be used known catheters occurring disadvantages in connection with the removal of secretions can occur.

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Claims (6)

Patent claims: 1. Endotracheal catheter for artificial ventilation with a catheter tube that is open on both sides and that runs along one of the tubes near its lower end! Section is surrounded by a cuff to form a gas-tight chamber delimited by its outer surface and its inside, with iur the end edges of the cuff enclosing the catheter tube in a gas-tight manner and the outer wall of the cuff by building up pressure in the chamber with the aid of an air supply line opening into it on the trachea wall to the plant can be brought, characterized in that the chamber (13 »14) is separated into two gas-tight insulated compartments (13» 14) by an inner cuff (12) concentric to the cuff (6), üna the catheter tube (4) in the Area of the section (5) has at least one opening (11) in the pipe wall . 2. Endotracheal catheter according to claim 1, characterized in that the end edges (7, 8) of the cuff (6) enclose the end edges of the inner cuff (12) which in turn enclose the catheter tube (4). - 21 - 1 ü 9 ίί ? ■. ' 0 h 9 6 - 21 - 3 · Endotraeheal catheter according to claim 1 or 2, characterized characterized in that the end edges (7, 8) of the collars on top of each other and on the catheter tube (4) are glued on. · 4.'Endotraeheal catheter according to claims 1 to 3, characterized in that the end edges (7, 8) of the cuffs through a λ Klemmverbin- are dung to each other and mounted on the catheter tube (4). 5. Endotraeheal catheter according to claims 1 to 4, characterized in that the wall of the catheter tube (4) in the tube section (5) has two elongated openings (11). 6. Endotraeheal catheter according to claims 1 to 51, characterized in that two pairs of cuffs are attached to the catheter tube (4 ^{) at a distance from each other, one near the lower end of the tube (4 1} ) and the other near the the upper end of the pipe. 1 ü 9 fc: - '"s / I) b 9 6 Blank page