EP0155009B1 - Medical tube - Google Patents

Abstract

Medical probe or tube suitable in particular for enteral feeding and comprising a flexible tube which has at its distal end a closure cap and at its proximal end a connecting means, and a mandrin with securing means formed corresponding to the connecting means, wherein at the distal end of the tube near the closure cap in the tube openings are disposed and the closure cap has a gelatin coating, and preferably on the closure cap over the gelatin coating a further coating of gastric-juice-resistant material is disposed and preferably in the cap a metal head is located.

Description

The present invention relates to a medical probe, in particular for enteral nutrition, according to the features of the preamble of claim 1.

Medical probes for enteral nutrition are already known. In general, these probes consist of the actual probe tube, at the distal end of which a closure cap is arranged, and the proximal end of which there are connecting devices via which the probe with the nutritional pump and further feed devices (such as further tubes and the like) for food and the like. or is connected to the stylet, and a stylet. The stylet serves to temporarily stiffen the relatively soft probe tube. It facilitates the placement of the probe and is removed after the placement or placement of the probe. PVC, polyurethane or silicone is generally used as the material for the probe tube, while the sealing cap is made of polyethylene or silicone.

Tube feeding has become particularly important in recent years. The indication for artificial nutrition is always given when a patient is not allowed to eat, cannot eat or does not want to eat. The respective nutritional therapy is tailored to the condition of the respective patient. This nutritional therapy is not only important in the postoperative or post-traumatic area, but also in diseases that are associated with a disturbance in the absorption or digestion of nutrients and as a complementary therapy for cancer patients. So special nutrition is carried out for oral diseases, e.g. Operations in the oral and maxillary sinuses, paralysis of the chewing muscles, with continued loss of consciousness, e.g. in traumatic brain injuries, in ventilated and relaxed patients, e.g. Tetanus patients, in patients with refusal to eat for a psychogenic cause, e.g. in anorexia, in cancer patients who often have taste sensations, and in pediatrics. Special studies have shown that compared to total parenteral nutrition, less and less serious complications are involved and, moreover, cheaper than parenteral nutrition. However, this means that special nutrition is more advantageous than parenteral nutrition and, with a few exceptions, it is therefore preferred in the treatment of malnutrition.

In general, a distinction is made between nasogastric, nasoduodenal and nasojejunal special nutrition. For nasoduodenal and nasojejunal nutrition, probes with a sealing cap have previously been used as a guide bolus (e.g. made of mercury or water). However, placement of the feeding tubes requires intact gastroduodenal peristalsis. Occasionally, these probes can also be placed intraoperatively. The nasoduodenal and nasojejunal feeding tubes are used primarily in the field of conservative medicine for unconscious patients, long-term ventilation patients, relaxed patients and for premature babies. They are also of undisputed importance in the surgical field of severely malnourished patients for preparation for surgery, as an alternative to surgery and in post-treatment (e.g. chemotherapy or radiation therapy of malignant tumors). Especially when used for the nutrition of unconscious patients, cancer patients, premature babies and small children, who cannot actively help even with the placement, there are considerable difficulties and problems when placing the probes when using the previous probes, so that often the targeted and successful nutrition this patient is questioned.

Probes are already known which have a balloon as the guide bolus which can be filled with a liquid, for example mercury or water, which is intended to facilitate the placement of the tube. Such probes are known from DE-A 3 105 883, DE-A 2914609, DE-A 2 402 573, DE-A 2 524 030, DE-A 2 810 326, DE-A 2 721 548, the article by Rueff et al. in Munich Medical Weekly (1968, pages 470-474) and the catalog of the company Rüsch (1977, pages 15-19). In the first-mentioned patent, the balloon is glued to the probe with an agent that is soluble in the small intestine and can be removed by detaching after placement.

All known probes, which have a balloon, have the disadvantage that they can only be filled to a limited extent when they are first inserted through the nose, thus already placing them in the nose makes them difficult.

As the probe moves further through the esophagus, the balloon is then filled with the liquid. Here, too, there are considerable difficulties in moving the probe through the esophagus, since the liquid contained in the balloon evades the peristaltic movement of the esophagus and stomach, so that serious placement problems are also observed here. On the other hand, however, so far only probes with a metallic cap at the distal end have been used, which was only insignificantly thicker than the tube itself, so that this does not provide any placement aid.

From DE-A 2 824 893 a probe for enteral treatment is known which is provided with a detachable bolus at its end. Such an arrangement is disadvantageous because the unweighted tube often slips back into the patient's stomach, which is to be avoided in principle.

In this respect, the invention has for its object to develop the probe of the type mentioned in such a way that it can be easily moved by the peristaltic movement of the esophageal gastrointestinal tract after placement lies safely and does not disturb the digestive process.

This object is achieved by the features of the characterizing part of claim 1.

A cap enlarged in this way offers a better point of attack for the peristalsis of the esophagus, stomach and / or intestine, which is particularly important in the case of passive patients (eg, unconscious patients).

Suitable materials that can be absorbed by the patient's body are pharmacologically acceptable solidifying substances, such as agar, alginic acids, starches, arabic gum, pectin PVP, methyl cellulose and gelatin, gelatin being preferred.

Suitable as gelatin are all commercially available, usable for medical purposes gelatins, such as soft gelatin and hard gelatin, or gelatin masses, which, if appropriate, further additives suitable for medical purposes, such as plasticizers (such as sorbitol) glycerol, alkali metal salts (sodium salts) of ethyl p-hydroxybenzoate or propyl p-hydroxybenzoate, and water and the like. contain. Soft gelatin or a gelatin mass is preferably used which, in addition to gelatin, also contains sorbitol, glycerol, the sodium salt of ethyl p-hydroxybenzoate, the sodium salt of propyl p-hydroxybenzoate and water. A suitable and preferred composition of the gelatin mass used according to the invention is as follows:

This gelatin is broken down after placing the probe.

The thickness of the thickening layer is not critical and the coating layer should, however, be so thick that the placement of the probe is improved to the desired extent, but on the other hand does not hinder the placement of the probe, i.e. should be such that the probe bolus offers a favorable point of attack for peristalsis. Suitable thicknesses are 3-6, in particular 4-5 mm with a probe diameter of approximately 2 mm. The jump in thickness between the thickening layer and the probe is of particular importance, since this jump ensures improved probe transport. The thickness jump (or the maximum wall thickness of the thickening) is advantageously in a range from 0.5-2, preferably 1-1.5 mm.

The thickening layer is applied to a customary cap or stopper made of a suitable, medically compatible material, such as hard gelatin or plastic (e.g. made of polyolefin, in particular polyethylene, or silicone) arranged in the distal end of the probe tube.

On the thickening layer of the cap, a coat or a further coating layer made of acid-resistant material is applied. This additional coating layer not only further enlarges and solidifies the closure cap or probe tip and thus further facilitates the placement of the probe tube, but in particular provides a probe for nasoduodenal and / or nasojejunal nutrition, which due to the enlargement of the closure cap or probe tip (- bolus) easily - even in passive patients - and unaffected by gastric acid passes through the stomach and can be safely placed in the duodenum or jejunum. As a material for this further coating layer, one is used which is resistant to gastric acid or gastric juice, but in intestinal juice, i.e. in the intestinal milieu, is soluble. Examples of such materials are medically safe materials, such as anionic polymers made from methacrylic acid and methyl methacrylate, and mixtures thereof with other materials and with one another. Anionic polymers of methacrylic acid and methyl methacrylate, such as Eudragit S, Eudragit L and mixtures thereof (manufactured by Röhm Pharma), in particular Eudragit S, are preferred. Shellack and cellulose acetate phthalate are also suitable as coating material.

The thickness of the coating layer is not critical, but the coating layer should be so thick that the thickening layer is protected from the attack of the gastric juices and on the other hand not so thick that it dissolves too slowly and thus preventing any removal of the probe from the duodenum or jejunum. Suitable thicknesses are approximately 10-30 µm, in particular approximately 25 µm. The coating can be colorless, transparent, white or pigmented in a different color; it is preferably matched to the color of the probe tube.

To further facilitate the placement of the probes, particularly the nasoduodenal and nasojejunal probes, the closure cap advantageously has a metal head or metal plug in its bore, which is arranged at the distal end of the probe tube, or the closure cap can be designed as a metal head or metal plug. Such a metal head increases the weight of the probe and stiffens the distal end of the probe, thus considerably simplifying the placement or placement of the probe, particularly in the case of passive patients.

Suitable materials for the metal head or the metal plug are suitable, suitable metals for medical purposes, such as e.g. Stainless steel, precious metals and the like Metal heads or plugs made of V4A and V2A steel are used in particular.

The size of the metal head is not critical and should be in the usual size range for sealing caps or can be somewhat smaller, but should be large enough that the metal head can perform the desired function. The metal head suitably has approximately the same outer diameter as the probe, while its length is determined by the weight or the holder in the probe. Likewise, the metal head can have any suitable shape. It is preferably inserted in the shape of a plug into the distal end of the probe tube by means of a neck.

The thickening layer is then arranged over the sealing cap designed as a metal head or over the sealing cap comprising a metal head made of suitable, medically compatible material such as hard gelatin or plastic (e.g. polyolefin, such as polyethylene or silocon), over which the coating layer of gastric juice-resistant, in Intestinal juice soluble material, is applied.

The probe tube itself consists of a conventional material suitable for probes, such as PVC, silicone or polyurethane, preferably of silicone or polyurethane.

A stylet designed in the usual way is used to temporarily stiffen the relatively soft probe tube. If the metal head according to the invention is present at the distal end of the probe tube, the stylet opens into a depression or bore in the metal head or the neck part of this metal head in order to prevent the probe tube from kinking at the tip. This bore is preferably provided in the neck part of the metal head.

The probe tube has openings in the usual way in the region of the distal end, which allow food to escape. The number of openings is not critical. However, there should be so many openings that proper food leakage is permitted. There are preferably two to four, in particular three, openings. Likewise, marking lines are preferably provided in the usual way on the probe tube, which serve for orientation when the probe is placed.

The diameter and the length of the probe tube depend on the intended use and are in the usual range. Typically, nasogastric probes are 75 cm long and have an inner diameter of 2-4 mm; Nasoduodenal or nasojejunal probes have a length of preferably 1.25 m, an inner diameter of 1.2-1.6 mm and an outer diameter of 2-2.4 mm.

At the proximal end of the probe tube are customary connection devices, which are used once for attaching the stylet or later after placing the probe in the usual manner for receiving or connecting connecting lines or hoses, via which the probe with the nutritional pump or other supply lines for the food is attached, attached. These connection devices can be present, for example, in the form of a connector part with a Luer connection, a plug connection or the like. A plug-in connection or a connector part with a Luer cone is preferably used, in particular a connector part with a Luer cone.

The probe according to the invention is produced in the usual way. The metal head is preferably inserted into the distal end of the probe tube in a plug-like manner via a neck-shaped part of the metal piece. Then, for example, the distal end of the probe tube equipped with the metal head can be provided with the thickening layer by immersing the end of the distal probe tube provided with the metal head in a heated gelatin mass and then pulling it out in order to cover it with a further coating of gastric juice-resistant material coat what can be done in the usual way, if necessary by spraying. The immersion of the distal end in the heated gelatin mass is preferably done by oblique immersion, i.e. Immerse at an angle of less than 90 °.

In the following, the present invention is further explained with reference to the drawings.

• Fig. 1 eine schematische Seitenansicht einer bevorzugten Ausführuhgsform einer erfindungsgemäßen Sonde.
• Fig. 2 einen vergrößerten Längsschnitt durch das distale Ende der Sonde gemäß Fig. 1 entlang der Linie I-I.
• Fig. 3 einen Querschnitt durch das distale Ende der Sonde gemäß Fig. 1 bzw. 2 entlang der Linie 11-11.

Show it:

• Fig. 1 is a schematic side view of a preferred embodiment of a probe according to the invention.
• FIG. 2 shows an enlarged longitudinal section through the distal end of the probe according to FIG. 1 along the line II.
• 3 shows a cross section through the distal end of the probe according to FIGS. 1 and 2 along the line 11-11.

In Fig. 1, the probe tip or the bolus at the distal end of the probe according to the invention is denoted by 1 and by 2 the probe tube. At the proximal end of the probe there is a customary connection or connection device 3 for the stylet 6 or other supply or connection lines, which, as shown, can be in the form of a luer connection or can have any other suitable shape, e.g. can be in the form of a plug connection. In this connection device, the corresponding connection or connection device 4 of the stylet 6 is inserted, which is preferably so-called to facilitate handling. Handle strips 5 carries.

At the distal end of the probe tube, the metal head 7 is arranged in the probe tube 2 in the form of a plug. Above the metal head 7 there is a thickening layer 8 made of a material that can be resorbed by the patient's body, preferably gelatin, on which a coating layer 9 made of an enteric, enteric material (preferably Eudragit S) is applied. This thickening layer 8 advantageously has the dimensions mentioned above.

In the area of the distal end, one or more openings 10 are provided in the probe tube for the food to exit.

FIG. 2 illustrates an enlarged longitudinal section through the region of the distal end and the bolus of the probe according to the invention according to FIG. 1, the reference numbers corresponding to those used in FIG. 1. The probe tip or the probe bolus 1 with the metal head 7 which is placed on the distal end of the probe tube 2 and is inserted into the tube end in the form of a plug with the neck part 7a is clearly visible in the enlarged representation. The neck part 7a of the metal head 7 has a bore 11 for receiving the distal end of the stylet 6. This metal head can also have another suitable shape, e.g. it can be pear-shaped, or it can be essentially cylindrical.

As can be seen from FIG. 2, the thickening layer 8 is first applied to the distal end of the probe tube 2 and the metal head 7, and the coating layer 9 made of gastric juice-resistant, intestinal juice-soluble material is applied thereon. The openings 10 in the tube 2 are used for food leakage.

The cross section shown in FIG. 3 along the line 11-11 according to FIG. 1 or 2 shows how the distal end of the probe tube 2 surrounds the neck part 7a of the metal head 7 and even of the thickening layer 8 and the coating layer 9 made of the enteric, enteric-soluble Material is surrounded.

Claims (5)

1. Medical probe, in particular for the enteral feeding, comprising a probe tube (2) which has in the area of its distal end at least one opening (10) for the outlet of the food and which at said distal end is connected with a closure cap having a bore on that side facing the lumen of the probe tube (2) and with a mandrin (6) insertable into the probe lumen, characterized in that the closure cap comprises in its bore a metal head (7) or is embodied as metal head (7), that the metal head (7) comprises a bore into which the distal end of the mandrin (6) is insertable, that the closure cap is surrounded with a thickening layer (8) consisting of a material resorbable from the body of the patient, and that the thickening layer (8) is covered with a covering layer (9) of a gastric-juice-resistant material which is soluble in the intestinal juice.

2. Medical probe according to claim 1, characterized in that the thickening layer (8) consists of gelatin.

3. Medical probe according to claim 2, characterized in that the gelatin thickening consists of soft gelatin.

4. Medical probe according to claim 1, characterized in that the gastric-juice-resistant covering consists of an anionic polymer of methacrylic acid and methacrylic acid methyl ester.

5. Medical probe according to claim 1, characterized in that the metal head (7) comprises a neck portion (7a) which is inserted in a plug manner into the tube end.

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