Tolerance of hemodialysis: a randomized prospective trial of high-flux versus conventional high-efficiency hemodialysis.

Hemodialysis is frequently complicated by hypotension and associated symptoms. It has been suggested that these symptoms may be related to the biochemical changes caused by cellulosic dialysis membranes. In this study, a prospective randomized crossover trial was conducted comparing the incidence of hypotension and acute symptoms during dialysis with large-surface-area (1.6 m2) cellulosic (cuprophane [CUP]) and noncellulosic (polyacrylonitrile [PAN], AN69) membranes. Dialyzers were used for a single use only. There was no difference in predialysis BUN, predialysis blood pressure, intradialytic weight gain, blood flow, dialysis efficiency (urea reduction), dialysis duration, hematocrit, or erythropoietin dose between the two study phases. When these clinical characteristics were matched, there was no difference in the number of episodes of hypotension (CUP, 19 +/- 3; PAN, 22 +/- 3; P = not significant [NS]). The incidence of symptomatic hypotension, as reflected by the number of episodes of hypotension requiring more than 100 mL of saline for correction, was also not different between study phases (CUP, 10 +/- 1; AN69, 11 +/- 2; P = NS). The incidence of intradialytic symptoms, including emesis, cramping, headache, angina, pruritus, and bronchospasm, was similar during the two study phases (CUP, 11 +/- 2; AN69, 10 +/- 1; P = NS). It was concluded that noncellulosic membranes do not offer any significant advantage over cellulosic membranes in reducing the acute complications of hemodialysis.

Silastic cuffed catheters for hemodialysis vascular access: thrombolytic and mechanical correction of malfunction.

Silastic cuffed catheters are assuming a greater role in providing long-term vascular access for hemodialysis patients. However, catheter thrombosis, fibrin sheath formation, and catheter malposition are recurrent problems that reduce extracorporeal flow rates and shorten catheter life. We reviewed 163 consecutive episodes of catheter malfunction that occurred in 121 catheters in 88 patients over a 3.5-year period. Intraluminal instillation of urokinase was successful in reestablishing an extracorporeal flow rate of > or = 300 mL/min in 74% of episodes. The 42 remaining episodes (26%) were radiologically evaluated. Two catheters required replacement for catheter kinking or insufficient catheter length. Two additional catheters were malpositioned; both were successfully repositioned with percutaneous techniques. A fibrin sheath was detected encasing the catheter in 38 instances. The fibrin sheath was successfully stripped from the distal portion of the catheter in 36 of the 38 instances. Using endoluminal thrombolytic therapy and percutaneous mechanical techniques, we have extended the mean survival for catheters intended for permanent vascular access to 12.7 months and have allowed 95% of the catheters inserted for temporary use to reach their use goal. Tunnel tract infection and catheter-mediated bacteremia were the primary reasons for catheter removal.

Transluminal angioplasty of venous stenoses in polytetrafluoroethylene vascular access grafts.

Since 1984, percutaneous transluminal angioplasty (PTA) utilizing high pressure balloon catheters has been used as an initial approach to restore patency of PTFE (polytetrafluoroethylene, GORE-TEX) hemodialysis vascular access grafts. Seventeen stenotic lesions detected by fistulogram underwent elective PTA. Twelve of these lesions were detected after thrombectomy and five were detected because of increased venous pressures during dialysis. Fourteen attempts at PTA were completely successful in restoring functional patency to the vascular graft. Three attempts were unsuccessful; two of these three grafts were subsequently repaired surgically. Venous stenoses that extended far greater than 6 cm were not considered for PTA. We conclude that PTA is a technique of promise in the non-surgical salvage of failing PTFE grafts. PTA can prolong the useful life of PTFE vascular access grafts and can be performed on an outpatient basis, eliminating the hospitalization that is usually required for surgical revision.

Povidone-iodine sclerosis of pelvic lymphoceles: a prospective study.

Twelve patients presented for percutaneous catheter drainage of 13 postoperative pelvic lymphoceles. Six patients with 7 lymphoceles were treated with povidone-iodine sclerosis prior to catheter removal. Only 1 lymphocele (which continued to drain large amounts of fluid during and after the sclerosis procedure) recurred. Six patients with 6 lymphoceles had their percutaneous catheters removed without sclerosis. Fluid collections recurred in 3 instances, necessitating repeat percutaneous drainage (2 patients) or surgery (1 patient). Percutaneous therapy is the treatment of choice for patients with postoperative lymphoceles. Povidone-iodine sclerosis is often effective in preventing reaccumulation of fluid once the lymphocele cavity is collapsed.

Prospective evaluation of a Dacron cuffed hemodialysis catheter for prolonged use.

Double lumen subclavian venous hemodialysis catheters are in wide use in the United States to provide temporary vascular access. The disadvantages of these catheters include a high infection rate and short use-life (2 to 3 weeks). We evaluated a felt cuffed tunnelled jugular venous hemodialysis catheter (PermCath) to determine its ability to overcome these shortcomings and compared it with standard noncuffed double lumen dialysis catheters. Eighty PermCaths were inserted during this prospective study in patients needing temporary vascular access in excess of 1 month. Median use-life of these catheters was 8 weeks with a use range of 3 weeks to 5.4 months. Only four functioning catheters failed before elective removal. Despite the prolonged use-life there was only one episode of catheter mediated bacteremia. Seven catheters (9%) failed to function immediately after insertion. These failures were caused by catheter kinking in the region of the felt cuff. Thrombosis of the catheter lumen was the most frequent complication (137 episodes) but resolved in over 95% of the instances with urokinase instillation. Exit site infections (23 instances) were successfully treated conservatively. We conclude that the PermCath (Quinton Instrument Co, Seattle) is a safe and reliable new device with a low complication rate and a longer use-life than standard subclavian dialysis catheters. This longer use-life allows more time for maturation of primary arteriovenous (AV) fistulas and Tenckhoff peritoneal dialysis catheters, and provides time for the healing of infected vascular access grafts. Its primary disadvantage is the need for surgical insertion.