FI58591B - I KROPPENS HAOLIGHET INFOERBART MEDICINSKT ELLER SURGICAL INSTRUMENT - Google Patents

Description

ΓΒΐ «« AD PUBLICATION CQCOI

LBJ utlAggningsskrift 1 C Patent cy-nnatty 10 03 1031

Patent meddelat ^ ^ (51) Ky.lk.3 / lnt.ct3 A 61 M 16/00 SUOMI — FINLAND ai) 2592/72 (22) Hakamtapllvt —AMttkningadag 21.09-72 ^ ^ (23) Alkupllvl · - GiMglMtadag 21.09. 72 (41) Tullut lulkMcsl —Bltvltoff «ntll | 25.03.73 PMMttl. ) · Registry Board Nih «Mk * p« o,). kvO & Mm * pvm.-

Patents and Registration of the United States 7 Amekan uttajd odi utUkrwtM p «Mic« rad 28.11.80 (32) (33) (31) Pyydetty «cuoilniM — Ugfrt prlorltet 2 ^ .09- 71

England-England (GB) UU638 / 7I Tot eennayt etty-Styrkt (71) Smiths Industries Limited, Cricklewood Works, London N.W.2,

England-England (GB) (72) David Edward Cross, Folkestone, Kent, England-England (GB) (7 * 0 Leitzinger Oy (5 * 0 Medical or surgical instrument inserted into a body cavity - I kroppens hälighet införbart medicinskt eller kirurgiskt instrument

The invention relates to a medical or surgical device for insertion into a body cavity, comprising a tube and a pressure-inflated bellows sheath surrounding it, intended to be placed in a body cavity to provide a seal between the tube and the body cavity and having circumferential corrugations at least on the bellows.

Medical or surgical devices according to this definition are known in the treatment of humans and also animals and are generally in the form of tubes provided with a surrounding expandable bellows on some part of the tube. Examples of such tubes are found in the various forms of the inner tube of the tracheal trachea commonly used in anesthesia. In this case, the tube is inserted into the patient's trachea through the mouth or nose and has a bellows at its distal end that is pul-1 contactable to contact the tracheal wall and provides a seal between the tube and the trachea. A similar procedure is applied in tracheostomy, but in this case the tube with a bellows used is made so that it can be inserted into the trachea through a surgical opening in the neck of the patient.

58591

The seal, which is formed by both the endotracheal and tracheostomy tube with the bellows, is intended to ensure that any air or other gas given to the patient passes through the tube and also to prevent mucus, vomiting, or other upper respiratory tract material from entering the lungs. However, there is a risk of damage due to the inflation pressure exerted by the bellows on the tracheal wall, which can clog the blood-carrying capillaries in the wall and thus lead to necrosis of the tracheal tissue. The bellows used is generally in the form of a uniform cylinder or sheath and contacts the tracheal wall in an area so extensive that the healing of necrosis due to natural growth in adjacent intact areas and restoration of blood supply is usually very slow. However, the injury can lead to a more severe form of constriction due to the penetration of connective tissue into the area, and thus surgery may be required to prevent tracheal obstruction.

One proposal (Dr. P. D. Salpekar, British Medical Journal, January 29, 1966, p. 296) to reduce the risk of tracheal wall damage in tracheostomy involves the use of two axially spaced and independently inflated bellows. In this proposal, both bellows are blown alternately with each other so that the other is in use, forming the desired seal for only half the intubation time. Although this reduces the time of capillary occlusion at all points in the tracheal wall, it does not prevent the procedure from possibly involving large areas of necrosis that are slow to heal and regenerate.

The necrosis and the dangers and disadvantages of possible stenosis discussed above in the case of beam-endotracheal and tracheostomy tubes apply, respectively, to other beam-loaded devices for insertion into the body cavity, such as catheters used elsewhere in the body.

It is an object of the present invention to provide a medical or surgical device of a defined type which makes it possible to reduce such hazards and disadvantages.

To achieve this object, the medical or surgical device according to the invention is characterized in that the bellows sheath 58591 has three or more spaced-apart corrugated ridges for contact with the body cavity wall, leaving the bellows ridges interlocking with the bellows recesses.

The bellows-sheathed device of the present invention contacts the body only at discontinuous sites, substantially reducing the possibility of extensive and uniform necrosis areas with a long recovery time. In addition, the solution according to the invention has the advantage that the efficiency of the sealing is substantially increased. This is because the numerous corrugated ridges of the bulged bellows sheath form a Laby-like seal together with the corrugated recesses between the corrugated ridges. The corrugated recesses, when closed relative to each other when the ridges touch the wall of the body cavity, ensure that any leakage in the longitudinal direction of the seal is reduced by the pressure pockets generated by the possible leakage in successive corrugated recesses.

The medical or surgical device of the invention may be an endotracheal tube or a tracheostomy tube and the bellows may be corrugated along its entire length or only part of its length.

Exemplary medical and surgical devices with bellows diapers according to the present invention will now be described with reference to the accompanying drawings, in which Figure 1 shows an endotracheal tube provided with a corrugated bellows diaper according to the present invention, Figures 2 and 3 show conditions which can be applied a quality endotracheal tube and an endotracheal tube of Figure 1 for insertion into the trachea; Figure 4 shows a bellows-sheathed tracheostomy tube according to the present invention; and Figures 5 and 6 show two alternative shapes of the bellows sheath that can be applied to the endotracheal tube and tracheostomy tube of Figures 1 and 4, 58591

Referring to Figure 1, the endotracheal tube includes a tube 1 having a hole or cavity 2 constant throughout its length and having an oblique, distal tip 3. The bellows sheath 4 surrounds a portion of the tube 1 near the oblique tip 3 and is formed of a short and corrugated sleeve piece the wall thickness is uniform and glued or otherwise sealed at both ends to the pipe 1. The bellows jacket 4, with its undulating outer surface and axially spaced circumferential ridges 5, forms a bellied sphere surrounding the part of the pipe wall 8 which is the opening from the slot 7 6 around. The slot 7, which runs along the pipe inside the pipe wall 8, is closed at the tip 3, and at a point about 2/3 of the length of the pipe 1 from the tip 3, there is an airtight connection to an external air duct 9 sealed to the wall 8.

Air coming through the opening 6 from the slot 7 for bulging the bellows jacket 4 is supplied to the air duct 9 via a standard connection 10. The supply of air to the air duct 9 in this way expands the picked bellows sheath 4, forcing the smooth curved ridges 5 into contact with the inner trachea wall of the intubated patient. This contact forms an effective labyrinth seal that effectively withstands the aeration pressure applied to the patient through the cavity 2 and prevents the exhalation of pharyngeal secretions and other substances from the upper airway. The bulging pressure of the bellows jacket is maintained by using a plug 11 inserted into the connector 10 as shown, and can be checked for bulging of the check ball 12 connected to the air line 9.

The corrugated bellows sheath 4 of the endotracheal tube, described above with reference to Figure 1, contacts the tracheal wall or mucous membrane in discrete strips rather than through the entire wide bellows region characteristic of the known bellows shape, which is a uniform cylindrical or barrel sheath. The situation that occurs during intubation using, for example, barrel-shaped bellows is illustrated in Figure 2, while the situation that occurs during intubation using the corrugated bellows sheath 4 of the present invention is illustrated in Figure 3.

As shown in Figure 2, the smooth barrel-shaped bellows 14 contacts the ciliated columnar epithelium of the tracheal mucosa over a substantially uniform area. The applied pressure tends to clog the mucosal capillaries C, which pass through longitudinally elastic causes F extending from the submucosal layer 585 and which act to supply blood to the epithelium E at a pressure between 12 and 30 mm of mercury. The blowing pressure for effective sealing of the bellows 14 in the trachea exceeds the ventilation pressure, which is usually set between 14 and 15 mm of mercury, but which can occasionally reach a value as high as 60 mm of mercury. Clogging of the capillaries C and subsequent necrosis and possibly stenosis is thus quite likely.

A similar consideration applies to the conditions of the corrugated bellows 4 shown in Fig. 3, but in it the higher sealing efficiency of the labyrinth seal provided by the axially spaced corrugated ridges 5 allows a lower blowing pressure to be used to bulge the bellows. The probability of necrosis and possible constriction is thus reduced and in any case limited to separate lanes, which is clearly different from a large uniform area. Thus, if death occurs when using corrugated bellows, the fact that the damage is limited to discrete bands promotes more rapid natural healing and regeneration.

Although the advantages of the corrugated bellows sheath 4 have been referred to above especially in connection with the endotracheal tube, they are equally suitable for a tracheostomy tube with a corrugated bellows sheath. However, these advantages do not necessarily require the use of a bellows sheath, such as a bellows sheath 4, which is corrugated along its entire length, but can only be realized when partially corrugated. Figure 4 illustrates a shape of a tracheostomy tube with a partially corrugated bellows sheath 4.

Referring to Figure 4, the curved tube 21 of the tracheostomy tube terminates in a conventional tube 22 and an attachment strip 23. The bellows sheath 24 surrounds a portion of the tube 21 near the distal end 25 and can be inflated from an air duct 26 associated with a check ball 27. The air duct 26 is connected to 21 and is closed at the distal end 25. The slot 28 communicates with the interior of the bellows sheath 24 through openings 29 and 30 passing through the wall of the two tubes.

The bellows sheath 24 has two separate adjacent ridges 31 and a narrow rounded shoulder 32 evenly shaped into a conical 58591 distal portion 33. Contact with the esophagus as the bulge 24 bulges occurs in the shoulder 32 and ridges 31 so that all necrosis is limited to just three distinct band. Also in this respect, however, the fact that the bellows sheath 24 is formed of a strong but very thin plastic material so that it is normally shrinkable and can be made to fully stiffen and seal effectively at low blowing pressure is reduced.

Figures 5 and 6 illustrate two modified shapes of a collapsible bellows sheath which may alternatively be used in place of the bellows sheath 24 of Figure 4 or in place of the bellows sheath 4 of Figure 1. Compared to the bellows sheath 24 of Figure 4, each of these alternative bellows sheaths has three adjacent corrugated ridges 31 'and the bellows sheath of Figure 6 is associated with an elongated, cylindrical shoulder 32' at its distal end.

The various corrugated bellows sheaths illustrated in Figures 1 and 4 to 6 may be formed of softened polyvinyl chloride (or optionally polyurethane) by blow molding. Alternatively, an immersion method may be used in which a suitably shaped casting core preheated to a temperature of about 210 ° C is immersed in a polyvinyl chloride paste. The casting core coated with the paste in the latter process is immersed in an oven at about 280 ° C for about 1 1/2 to 2 1/2 minutes (depending on the size of the bellows jacket) and administered. then cool to a somewhat lower temperature at which the finished bellows jacket can be wound off ready to be sealed to the main pipe. This latter tube may also be made of polyvinyl chloride and may be extruded to contain an X-ray opaque material (suitably limited to an elongate band integral with the tube wall) and a suitable plasticizer which causes a slight softening at body temperature.

Claims (3)

58591 A medical or surgical device for insertion into a body cavity, comprising a tube (1, 21) and a surrounding pressure bulging bellows sheath (4, 24) for placement in a body cavity to provide a seal between the tube (1, 21) and the body cavity, and the outer surface has circumferential corrugations at least when the bellows sheath is in a bulging state, characterized in that the bellows sheath (4; 24) has three or more spaced corrugated ridges (5; 31, 32) for contact with the body cavity wall, leaving the bellows sheath (4) (24) recesses which are closed relative to each other during sealing. Device according to claim 1, wherein the bellows sheath (4; 24) surrounds a part of the length of the tube (1; 21), characterized in that the axially spaced bellows sheath folds (5; 31, 32) surround the tube (1; 21) parts. Device according to Claim 2, characterized in that the bellows sheath (24) is corrugated only over part of its length (Figures 4, 5 and 6).