Ash Split Cath® in Geriatric Dialyzed Patients

Vascular access is the essential step in performing hemodialysis in uremic patients. In the absence of a permanent and utilizable native arterio-venous fistula, the use of a tunnelled catheter makes dialysis therapy possible. The Ash Split Cath, a recently introduced chronic hemodialysis catheter, was inserted in five patients (7.1 % of our prevalent dialysis population) because of repeated venous thrombosis in three patients and a poor venous tree in two. The mean age of patients was 78 years ± 7. The average blood flow rate was 250 ± 50 ml/minute and the mean venous pressure 140mm Hg ± 35. Recirculation determined by low flux technique was less than 2 %. KT/V calculated 3 months after the catheter placement was 1.2 ± 0.02. During the follow-up we did not document any infection of the exit site or related to the catheter.

This device is simple to place, gives adequate dialysis treatment and is useful in geriatric dialyzed patients in whom the arterio-venous fistula can no longer be used.

Cuffed-tunneled Femoral Catheter for Long-term Hemodialysis

Background

Hemodialysis access is a challenging problem in patients with exhausted dialysis access sites of their upper extremities. Femoral arterio-venous polytetrafluoroethylene (PTFE) graft is often necessary. The safety and efficacy of cuffed tunneled catheters at the femoral site for long-term hemodialysis has not been extensively studied.

Methods

We inserted 14 cuffed-tunneled femoral catheters in 11 hemodialysis patients with exhausted dialysis access sites of their upper extremities. Access survival and risk of infection were compared with the 11 femoral PTFE grafts in 10 patients of our center during the same period. The choice of dialysis access was determined by the individual nephrologist. Access survival was defined as the achievement of a blood flow rate of at least 180 ml/min.

Results

The median survival of tunneled femoral catheter and PTFE graft were 166 days and 560 days respectively (log-rank test, p = 0.33). Seven of the 14 tunneled femoral catheter remained in use 3 months after insertion. The incidence of catheter- or graft-related infection was 0.38 and 0.23 episodes per 100 catheter / graft days for tunneled femoral catheters and PTFE graft respectively (p = 0.6). Five tunneled catheters and one PTFE graft had to be removed because of infection. Blood flow rates achieved were comparable between tunneled femoral catheter and PTFE graft.

Conclusions

Our preliminary data suggest that the cuffed tunneled femoral catheter has reasonable access survival and an acceptable risk of infection. It may provide a safe and effective access for long-term hemodialysis patients with exhausted access in their upper extremities, especially high risk patients who are not suitable for femoral PTFE graft creation.

Anticoagulation therapy for the prevention of hemodialysis tunneled cuffed catheters (TCC) thrombosis

BACKGROUND

Chronic oral anticoagulation is currently used to avoid thrombosis and the malfunction of tunneled cuffed catheters (TCCs) for hemodialysis (HD). The aim of the study was to assess the efficacy of early warfarin administration, after TCC placement, in comparison to its administration after the first thrombosis or malfunction event of the TCC.

PATIENTS AND METHODS

One hundred and forty-four chronic dialysis patients, who underwent TCC placement between June 2001 and June 2005, were randomized into two groups: 81 patients, group A, started oral anticoagulation 12 hr after the TCC placement (target international normalized ratio (INR) 1.8-2.5), in association with ticlopidine 250 mg/die; 63 patients, group B, started warfarin after the first thrombosis/malfunction episode (target INR 1.8-2.5) in association with ticlopidine 250 mg/die. The efficacy of oral anticoagulation therapy in preventing TCC thrombotic complications was evaluated in a 12-month follow-up period, after TCC placement, in terms of: a) the number of patients with thrombotic-malfunction events; b) the number of thrombotic-malfunction events with urokinase infusion (events/patient/year); c) intradialytic blood flow rate (BFR, ml/min); d) negative blood pressure (BP) from the arterial line of the TCC (AP, mmHg); e) positive BP, in the extracorporeal circuit from the venous line (VP, mmHg); and f) bleeding complications.

RESULTS

Ten patients (12%) in group A showed TCC thrombosis/malfunction vs. 33 patients (52%) in group B (p < 0.01). In group A, 0.16 events of thrombosis/malfunction per patient/year vs. 1.65 in group B (p < 0.001) were ob-served. BFR was respectively 305 +/- 34 vs. 246 +/- 42 ml/min (p < 0.001). AP was -124 +/- 13 in group A vs. -174 +/- 21 mmHg in group B (p < 0.05). VP was 112 +/- 28 in group A vs. 168 +/- 41 mmHg in group B (p < 0.05). No patient showed any bleeding events.

CONCLUSIONS

Early warfarin therapy allows a significant reduction in TCC thrombotic complications and an improvement in both arterial and venous fluxes in comparison with the same therapy administered after the first TCC thrombotic/malfunction event. This therapy did not induce any bleeding complications in the patients included in the study.

Placement, performance and complications of the Ash Split Cath hemodialysis catheter

A tunneled catheter is the alternative vascular access for those patients in need of hemodialysis who cannot undergo dialysis through an arterio-venous fistula or a vascular graft. This study was undertaken to evaluate the performance of the Ash Split Cath, a 14 French chronic hemodialysis catheter with D-shaped lumens and a Dacron cuff. After tunneling through a transcutaneous portion the catheter enters the venous system, where it splits into two separate limbs. Data regarding catheter positioning, function and adequacy of dialysis were collected from two hemodialysis facilities. Twenty-eight Ash-split catheters were placed in 28 patients, with no complications, and immediate technical success was 100%. Patients were followed up for a total of 7,286 catheter days. No catheter-related infections were observed. Only one catheter failed after 15 days, with a primary catheter patency of 96% for the whole study length. Mean blood flow was 303 +/- 20 ml/min at 1 week after insertion, 306 +/- 17 ml/min at 3 months, 299 +/- 44 ml/min at 6 months, and 308 +/- 16 ml/min at 12 months. With a mean dialysis session duration of 234 +/- 25 minutes, adequate dialysis dose was observed for 96% of catheters, as reflected by a mean urea reduction ratio (URR) of 71% +/- 8 or a mean urea kinetic modeling, or Kt/V, value of 1.51 +/- 0.3 during follow up. In conclusion, compared with previous studies we report the best permanent catheter performance, confirming that the Ash-split catheter is a good alternative for vascular access in hemodialysis patients who are not candidates for surgical A-V fistula or graft placement.