Patient-tailored, central-vein catheters

Details Patient-tailored, central-vein catheters Patient-tailored, central-vein catheters

2001-04-26

2003-07-15

Yuen, Henry C. (Department: 3354)

Surgery

Means for introducing or removing material from body for...

Treating material introduced into or removed from body...

C604S175000

Reexamination Certificate

active

06592565

ABSTRACT:

BACKGROUND OF THE INVENTION
Jugular and subclavian catheters are intended as a permanent blood access for fluid delivery into the blood stream or egress of blood. Although these catheters may be used for various purposes including treatment of acute renal failure, they are essentially intended for treatment of chronic renal failure. The invention will decrease the rates of thrombosis and infections and prolong the overall survival of the catheters.
There are numerous manufacturers producing various implantable catheters, and the line of products is changing every year. An extensive review of all available catheters for acute and chronic hemodialysis was published in 1995 (Twardowski ZJ: Percutaneous blood access for hemodialysis. Seminars in Dialysis 1995; 8: 175-186).
Dual Lumen Catheters
These catheters are made of silicone rubber or polyurethane. Silicone rubber is less thrombogenic than polyurethane. Polyurethane is thermoplastic, while silicone rubber is thermoset and does not soften at body temperature. Depending on the manufacturing process, the silicone rubber catheter may be made softer or harder, but is usually made soft. Most currently used catheters have dual lumens and are provided with a single polyester cuff. Most dual-lumen catheters have a beveled inflow bore and a few side holes for inflow. Almost all catheters are radiopaque or are provided with radiopaque stripe.
The catheters are inserted transcutaneously through the subclavian or jugular veins using a peel-away sheath method or surgically through the jugular vein into the superior vena cava or right atrium. Femoral veins are usually not used as a long-term access for hemodialysis. Jugular veins serve as a primary insertion site, because complication rates associated with insertion through the subclavian veins are significantly higher.
Although historically the catheters were inserted with various approaches, currently the catheter is usually inserted through the Sedillot triangle (between the sternal and clavicular heads of the sternocleidomastoid muscle) using the Seldinger (Seldinger SI: Catheter replacement of needle in percutaneous arteriography; new technique. Acta Radiol 1953; 39: 368-376) method. In this method the vein is punctured with a large bore needle and a guide wire is inserted into the vein through the needle. The needle is withdrawn, the skin tunnel is created by a small incision, the entrance into the vein is prepared by a dilator. The subcutaneous tunnel is created with a trocar, the catheter is inserted through the tunnel and introduced into the vein using peel-away sheath. Then the tip of the catheter is advanced through the brachiocephalic vein into the superior vena cava or right atrium. The surgical method is similar, with the exception that the incision over the Sédillot triangle is bigger and the vein is punctured under the direct vision.
There are two method of subcutaneous tunnel creation. Because most catheters have an attached Y extension for connection with the dialyzer lines, the tunnel must be created from the skin exit to the site of the vein puncture (standard tunneling method). Another method, as described in my previous patents (U.S. Pat. Nos. 5,209,723; 5,405,320; and 5,509,897) requires that the catheter be tunneled from the vein puncture site to the exit (reversed tunneling method). Such a method is possible if the Y extension is attached to the catheter after the catheter is pulled through the exit. In both methods the subcutaneous tunnel is created over the clavicle; thus the catheter in the tunnel has more or less a reversed “U” shape.
Mutatis mutandis,
an insertion through the subclavian veins is similar to that through the jugular veins. The puncture ofthe subclavian vein is done just below the clavicle and slightly outside of the midclavicular line.
To prevent blood recirculation, most dual lumen catheters have inflow and outflow bores staggered approximately 2 cm, with outflow bore distal to that of inflow bore. Our studies (Twardowski Z J, Van Stone J C, Haynie J: All currently used measurements of recirculation in blood access by chemical methods are flawed due to intradialytic disequilibrium and/or recirculation at low flow Am J Kidney Dis 1998; 32 (6): 1046-1058.) showed that at the high blood flow (over 300 mL/min) blood recirculation is only moderate, even in catheters with a flush tip. Various tip configurations aiming at decreasing clot formation were patented (U.S. Pat. No. 5,509,897; 5,569,182; and 5,685,867).
Single Lumen Catheters
For subclavian vein catheterization, single lumen catheters were used in 1969 (Erben J, Kvasnicka J, Bastecky J, Vortel V: Experience with routine use of subclavian vein cannulation in haemodialysis. Proc Eur Dial Transpl Assoc 1969; 6: 59-64), a long time before two lumen catheters were invented. Canaud et al.(Canaud B, Béraud J J, Joyeux H, Mion C: Internal jugular vein cannulation using 2 silicone rubber catheters: A new, simple and safe long-term access for extracorporeal treatment. Nephron 1986; 43: 133-138. Canaud B, Béraud J J, Joyeux H, Mion C: Internal jugular vein cannulation with two silicone rubber catheters: a new and safe temporary vascular access for hemodialysis: Thirty months' experience. Artif Organs 1986; 10: 397-403.) decided to continue the method of Erben et al. using two single-lumen catheters, but they changed material from polyethylene to silicone rubber and used jugular instead of subclavian vein insertion site. The catheters with inner/outer diameters of 2.0/3.2 mm had 6 side holes on the 5 distal centimeters. The catheters were exteriorized by reversed tunneling (from the cervical incision to the skin exit), and extension-tubing adapters were attached to the catheters after their externalization. The catheters were not provided with cuffs.
An important advantage of single catheters is its smaller entrance into the vein and smaller exit site. With the smaller entrance it is more likely to be able to cannulate the vessel repeatedly. The smaller exit is less prone to infections; however, infections were the most common complications of long-term jugular vein catheters (Canaud B. Leray H. Béraud J J. Mion C. Acces vasculaire temporaire: du peripherique au central, du temporaire au permanent. [Temporary vascular access: from peripheral to central, from temporary to permanent]. Nephrologie. 1994; 15: 53
—
9.). It is worth stressing that these catheters were not provided with cuffs.
Single lumen catheters for single needle dialysis were developed in the late 1980's. A regular, Tenckhoff peritoneal dialysis catheter was used by Liggett et al. (Liggett R A, Kearney M M: Tenckhoff catheter as a primary hemodialysis vascular access. Dialysis & Transplantation,1988; 17: 522-524, 546.) Thrombotic complications of this catheter were frequent as an anticoagulant was leached out of the tip through side holes. A single, silicone rubber catheter with fish-mouth tip to prevent sucking against the vessel wall was developed by Bionic Company (Friedrichsdorf, Germany) and the results with this catheter were reported by Demers et al. (Demers H G, Siebold G, Schielke D J, Mueller W, Niemeyer R, Hoeffler D: Soft right atrial catheter for temporary or permanent vascular access. Dialysis & Transplantation, 1989; 18: 130-139.) The catheter had a single polyester cuff as a barrier to periluminal bacterial penetration, and no side holes at the tip to avoid sucking of the intima and/or leaching out of anticoagulant.
Tesio et al. (Tesio F. De Baz H. Panarello G. Calianno G. Quaia P. Raimondi A. Schinella D. Double catheterization of the internal jugular vein for hemodialysis: indications, techniques, and clinical results. Artif Organs. 1994; 18 :301
—
4.) used catheters very similar to those of Canaud. These were silicone rubber catheters with internal/external diameters of2.0/3.2 mm and provided with 6 side holes on the 4 distal cm. Unlike Canaud catheters, Tesio catheters were provided with a 1 cm olive-like device to better fix the cannula in the tunnel. A recent model of Tesio catheter is provided w

Affiliated with

Also associated with

Rating

Patient-tailored, central-vein catheters does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Patient-tailored, central-vein catheters, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Patient-tailored, central-vein catheters will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-3046936