Hemodialysis insertion

Fig. 1. A, hoUow-fiber spool B, hoUow-fiber cartridge employed ia hemodialysis C, cartridge identical to item B demonstrating high packing density D, hoUow-fiber assembly employed for tissue ceU growth E, hoUow-fiber bundle potted at its ends to be inserted into a cartridge or employed ia a situation...

C Treatment for catheter-related infections is often initiated empirically, with definitive therapy based on culture results and susceptibility. Dialysis catheters are usually permanently inserted lines, and patients on chronic hemodialysis are at higher risk for developing catheter-related infections secondary to staphylococcal species, particularly coagulase-negative staphylococci. Oral vancomycin is not appropriate because it does not achieve adequate blood levels to treat systemic infections. 

Coagulase-negative Staphylococcus species, particularly S. epidermidis, are the most common causes of catheter-related bacteremia [25], Heavy colonization of the skin-insertion site has been shown to be strongly correlated with catheter-related bacteremia. In hemodialysis patients, the risk of S. aureus bacteremia is six times greater than in nonhemodialysis patients. And numerous incidents of intravascular infection have been traced to microbially contaminated topical disinfectants. 

Central catheters have been shown to be the most important risk factor in nosocomial Candida infections, which rival in seriousness any underlying disease. Catheters inserted in the subclavian or internal jugular vein have an infection rate of 3-5%—in some hospitals, 7-10%. Percutaneous inserted, noncuffed venous catheters used in hemodialysis are associated with the highest infection rate, 10%. 

The anatomic location for temporary central venous catheter (CVC) insertion and placement can be dictated by certain patient or disease restrictions, but the most common sites are the internal jugular vein (neck), the femoral vein (groin), and the subclavian position (upper chest). The internal jugular approach is the first choice for placement of a hemodialysis CVC, while femoral placement is favored when rapid insertion is essential (Canaud et al., 2000). Subclavian vein access has fallen from favor because of a higher incidence of thrombosis and stenosis associated with this site, which can ultimately prevent use of the veins in the downstream vascular tree for high-flow applications such as dialysis (Cimochowski et al., 1990 Schillinger et al., 1991). 

The Scribner shunt, a U-shaped Teflon tube, is the creation of Chicago-born Belding Scribner. The shunt, inserted between an artery and vein in a patient s forearm, could be opened and connected to the artificial kidney machine during dialysis. Teflon was relatively new to the biomedical community at the time, and its nonstick properties made it less likely to clot. Before Scribner s shunt, a patient could receive only a few dialysis treatments before doctors would run out of places to connect the machine to the patient. The shunt was first used on March 9, 1960, on Clyde Shields, who was dialyzed repeatedly for eleven years. Another patient was dialyzed for thirty-six years, undergoing 5,700 cycles of hemodialysis, before his death. In 1962, Scribner and American physician James Haviland developed the first free-standing dialysis center in the world, the three-bed Seattle Ar-tihcial Kidney Center. 

In patients with CKD, preservation of the integrity of peripheral and central veins is of vital importance for future hemodialysis access. Avoid i.v. infusion or vein puncture in the forearm and upper arm veins at both arms whenever possible. Insertion of venous access devices carries the risk to injure the veins and thereby incite phlebitis, sclerosis, stenosis or thrombosis and has to be avoided. Whenever a central venous catheter is needed, catheterization of the internal jugular or femoral vein is always preferred. Use of subclavian vein should be... 

Geddes CC, Walbautn D. Fox JG, Mactier RA Insertion of internal Jugular temporary hemodialysis carmulae by direct ultrasound guidance - a prospective comparison of experienced and inexperienced operators. Clin Nephrol 1998 50 320-325. 

Oliver MJ, et al Risk of bacteremia from temporary hemodialysis catheters by site of insertion and duration of use a prospective study. Kidney Int 2000 58 2543-2545. 

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