Siliconizing intestinal decompression tubes

Siliconizing

Intestinal

Decompression

Tubes

MEYER 0. CANTOR, M.D., Detroit, Michigan From cbe Grace and Sinai Hospitals, Detroit, Michigan.

ILICONES are relativeIy inert polymeric subwhose basic structure is a chain of a succession of silicon and oxygen atoms (S&O--Si-0) rather than the carbon chain (C-C-C). These poIymers may be prepared in liquid, resin, or rubber form. One or more organic radicaIs are attached to each sihcon atom thus producing an organosihcon with a wide variety of uses. Since the organosiIicones are physioJogicaJJy inert, the only value such compounds have is due to their physica properties: (I) they have Iow surface tension permitting the siIicone ffuids to spread easily; (2) they are repeIIent to water or liquids; (3) they wiI1 not support bacteria1 growth; and (4) they have abhesive properties. Chemically the silicone materials have been proved to be non-toxic or of a Iow order of toxicity. Application to the skin or injection of the ffuid into the tissues causes no infIammatory reaction. GIass tubing and bottles treated with siIicone have been and are at present extensiveIy used for transfusions of fresh whoIe blood. After a carefu1 review of the avaiJabJe literature, McGregor [I] reported that a11 studies to date [2-71 have given no indication that siIicone oiIs or preparations wiI1 cause toxicity of any type. In addition to an absence of toxicity, the siIicones have never shown aIIergenic properties irrespective of the method of administration. SiIicones have been rubbed into the skin, ingested and injected without producing any aIIergic reaction. The physica property which suggested the use of siIicones as a coating appIied to intestinal

S stances

American

Journal of Surgery.

Volume 100. October 1960

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decompression tubes is its abhesive power. This permits tubes treated with siIicone to repel water, blood, mucus and most organic materiaIs. PracticaJIy no materia1 wiI1 stick to the siIicones, nor do they support bacteria1 growth. Because of this abhesive property, decompression tubes treated with silicones should be much more comfortabIe for the patient since the nasopharyngea1 mucus wiJ1 not adhere to them. EarIy in 1959, Yonehiro reported to McGregor of Dow Corning Research Center that Wangensteen had been using Silastic tubing for nasogastric suction in patients requiring intestina1 decompression. This SiIastic tube contains no conventiona rubber. It is an eIastomeric compound comprising a siIicone poIymer and a fiJIer which is chemically bound to the polymer. Yonehiro reported being impressed by the comfort given to the patients using such SiIastic tubes as compared with the ordinary rubber intestina1 decompression tubes. However, the transparency of the SiIastic tube to x-ray fiIm and its softness were rea1 probIems interfering with proper intubation. In addition, silicone rubber is highIy permeabIe to oxygen and carbon dioxide which permits intestina1 gases to readiIy diffuse into them. Wangensteen suggested to Dow Corning that the tip be made radiopaque and the tubes be made stiffer for use as intestina1 decompression tubes. With this evidence, we decided to coat the intestina1 decompression (Cantor) tubes with sihcone. The siIicone was appIied to the inner and outer waIIs of the tubes as a Iiquid supplied by the CIay-Adams Company under the name of “SiIicIad.” At the June meeting of the Grace

SiIiconizing

IntestinaI

Decompression

Tubes

IB

1A

FIG. I. A, Cantor tube untreated with silicone. Note absence of reffection as compared with the treated tube. This surface is much rougher than that of the silicone-treated tube. B, Cantor tube treated with siIicone (C). Note the definite reflection indicating the presence of a coating. This surface was much smoother and far Iess irritating to the mucous membrane than the untreated tube.

HospitaI staff, an experimenta study invoIving the -use of these &cone treated tubes was reported. METHOD

Twelve patients with intestinal obstruction were used in this experimental study. These were divided into four groups of three vatients each. In the first groip (tube U), untreated Cantor tubes were used. In the second group (A), the Cantor tube was treated with a light Iayer of siIicone. (Fig. IA.) In the third group (B), the Cantor tube was treated with a heavier concentration of siIicone, and in the fourth group (C), a fairIy heavy coating of siIicone was appIied. (Fig. I B.) The tests were performed from two points of view. First, we were interested to determine whether there was any difference in the reaction of the patient to each specific tube. In other words, were the patients more or less comfortable with each specific tube. Since the tubes were a11the same size and the same kind of rubber, any differences would of necessity be due to the effect of the different concentrations of siIicone upon its surface. The effect of the different tubes upon the nasopharyngeal mucosa wouId be reffected in an outpouring of mucus. The most uncomfortabIe tubes wouId be the ones which caused the most mucus to be formed by the patient whereas the most comfortabIe I

585

tube wouId be the one causing the least amount of mucus to’ form and to adhere to the tube. The second point of view was to determine whether the mucus adhered to the tubes in different ways and what differences there were, if any, in the ease with which the tubes couId be cIeaned when they were returned to central supply. RESULTS I. AI1 the siIicone-treated tubes were much better toIerated by the patient than were the untreated tubes. Much Iess mucus was poured out by the patients whose tubes were treated with silicone than by those patients, used as controIs, whose tubes were not treated with siIicone. One patient, used as a contro1, whose tube was not treated with siIicone compIained so much that the untreated tube was removed and tube A was inserted. When asked whether she noted any difference, she replied that tube A was much more comfortabIe. When this tube was removed on the fifth day, considerabIy Iess mucus was found on it than on the untreated tube previousIy removed. 2. A comparison of tubes A, B and C resuIted in the observation that tubes B and C were much better toIerated by the patient than was tube A or the untreated tubes. Less mucus was found on tubes B and C than was

Cantor saving to the hospita1 in that more time is Ieft for other work. The silicone-treated intestina1 decompression rubber tubes have the foIIowing advantages over the SiIastic tubes: (I) they are resihent and elastic inhibiting knot formation such as may occur with softer tubes, (2) they are radiopaque and hence easily localized as compared with the transparent SiIastic tube, (3) they are much Iess permeabIe to intestina1 gases, (4) the siIicone-treated surface wiII not support bacteria1 growth.

the case with A. In addition, the mucus was much easier to remove on tubes B and C. 3. When the tubes were returned to centra1 supply, it was found that tube C was by far the best tube insofar as the adherence of mucus was concerned and the ease with which this mucus couId be removed. Tube B was aImost as good and tube A was a poor third. The untreated tubes were found to have considerabIe tenacious mucus which was removed with much more di&uIty than was the case with the silicone treated tubes. Tube C was found to Iose its stickiness after one use but the rubber remained soft and smooth and highIy resiIient. Our YcentraI SuppIy was greatIy impressed with tubes B and C considering them as improvement in the intestina1 decompression tube.

REFERENCES I.

2.

CONCLUSIONS

3.

It appears that the apphcation of siIicone to the rubber tube renders its surface smoother and much less irritating to the nasa1 mucosa. As a resuIt, much Iess mucus is poured out by the patient. Because of this, patients in whom the siIicone treated tubes were used were found to be far more comfortabIe. Upon the return of the treated tubes to centraI suppIy, a sihcone-treated tube was found to be much easier to cIean and hence permitted an appreciabIe saving in time to the girIs in this department. This should reflect itseIf in a

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MCGREGOR, R. R. SiIicones in Medicine and Surgery. Dow Corning Research Center, rg5g. ROWE, V. K., SPENCER, H. C. and BASS, S. L. Toxicological studies on certain commercia1 silicones and hydroIyzabIe siIane intermediates. J. Ind. Hyg. &’ Toxicol., 30: 332, Ig&. ROWE, V. K., SPENCER, H. C. and BASS, S. L. ToxicoIogic studies on certain commercia1 silicones. Arch. Ind. Hyg. TV Occupational Med., 1: 539, 1950. CUTTING, W. C. Toxicity of siIicones. Stanford M. Bull., IO: 23, 1952. KERN, S. F., ANDERSON, R. C. and HARRIS, P. N. Observations on the toxicity of methyl-silicone. J. Am. Pbarm. A. (Scient. Ed.), 38: 575, 1949. LARGENT. E.. BLACKSTONE, M. and ROTH, .I. Report on the-immediate toxicity of DC 200 &Iicone oi1 given oraIIy to rats. U. S. Air Force M. Service,

p. I, 1950. 7. WALKER, H. P. and SHEA, T. E., JR. SiIicone insuIation in submarines-toxicity. Tr. Am. Inst. Elec. Engrs., 67: 1232, 1948.

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