Abstract Multiwall surgical tubing, especially for stomach, thoracic or rectal use, has an inner, relatively thick transparent tube encased in a relatively thin, visually transparent, outer shell which contains a radiopaque material, so that as the X-radiation passes through the lateral edges of the composite tube it must pass through a relatively long path at the side edges of the tubing, while the central portion remains substantially transparent. Thus, the position of the tube is readily observed by fluoroscopy, while the flow of contrast media or clots may be observed in the central portion. As used for a heart, ureteral or vein intubation catheter, the multiwall tubing is formed of extruded polyethylene containing a nontoxic, radiopaqueplasticizing compound such as bismuth, oxychloride, which is encased in an extruded outer shell of transparent polyethylene having a hardness and exterior smoothness superior to that of the inner tubing, which outer shell also increases the angular resistance to twisting in use.
The tubing of claim 1 wherein said inner and outer portions are polyvinyl thermoplastics.
Claim 2
Dependent Claim
27 words
The tubing of claim 1 wherein the tubing has a diameter of at least three-eighths inch, and the outer shell has a wall thickness of 0.020 inch.
Claim 3
Dependent Claim
28 words
The tubing of claim 3 wherein the inner tubular portion has relatively high flexibility and softness, said shell having greater hardness and torque resistance than said inner portion.
Claim 4
Dependent Claim
100 words
A medIcal-surgical catheter tubing including an elongated, extruded tube of polyethylene containing a nontoxic, radiopaque substance intermixed therewith, and a relatively thin shell of extruded polyethylene encasing said tube and having a hardness and exterior smoothness superior to those of said tube, said tubing being highly flexible for conforming to tortuous body passages through which the tubing is passed yet having substantial angular resistance to twisting about its longitudinal axis so that the distal end will rotate in substantial conformity to twisting of the proximal end when the tubing is being passed through an is positioned in such body passages.
Claim 5
Dependent Claim
22 words
The tubing of claim 5 wherein the tube is of medium density polyethylene and the encasing shell is of higher density polyethylene.
Claim 6
Dependent Claim
15 words
The tubing of claim 5 wherein the radiopaque substance of said tube is bismuth oxychloride.
Claim 7
Dependent Claim
27 words
The tubing of claim 5 wherein the radiopaque substance in the thermoplastic material of said tube is a mixture of the organic iodine compound and bismuth oxychloride.
Claim 8
Dependent Claim
17 words
The tubing of claim 5 wherein said exterior shell is formed of polyethylene free of radiopaque material.
Claim 9
Dependent Claim
22 words
The tubing of claim 7 wherein the thermoplastic material of said tube is a mixture of polyethylene and an ethylene-vinyl acetate copolymer.