Successful systemic fibrinolysis in permanent hemodialysis catheter obstruction

Radiological placement of chest ports in pediatric oncology patients

A single center's procedural and follow-up results of radiological chest port placement in pediatric oncology patients are presented. Between July 2002 and December 2003, 37 children (20 boys, 17 girls; age range, 4 months to 16 years; mean 6.7 years) underwent chest port placement. All patients received only one port through the internal jugular vein access, and all of the implantations were performed in the interventional radiology suite. Our database and electronic charts were retrospectively reviewed to obtain follow-up data. All chest ports were successfully implanted. The mean catheter life was 223 days (range: 15-450 days), with a total of 8,258 catheter days. Twenty-eight ports are still in use, four patient deceased, one port was prematurely removed because of a late infection, and four patients were lost to follow-up. Infection rate was 2.7% (0.12/1,000 catheter days). Malfunction due to partial catheter thrombosis and fibrin sheath formation was observed in three patients (8.1% or 0.36/1,000 catheter days), and all were relieved with rt-TPA dwell. None of the ports were revised or removed because of blockage, malposition or difficulty accessing the port. The peri-procedural complication rate was 0%. Chest ports in children can be inserted in interventional radiology suites under imaging guidance with high rates of technical success. The rates of infection and complications are comparable to that of surgically placed ports.

Analysis of early failure of tunneled hemodialysis catheters

OBJECTIVE

Tunneled hemodialysis catheters are often placed by the interventional radiology service using sonographic guidance and fluoroscopy for safe and optimal placement. The aim of this study was to determine the causes of early failure (<or=7 days) of these catheters in our practice.

SUBJECTS AND METHODS

Data were prospectively collected for 639 radiologically placed tunneled hemodialysis catheters. The reason for catheter removal was recorded in each case. Tips of removed catheters were routinely sent for microbial culture.

RESULTS

Fifty-two (8.1%) of 639 catheters were removed within 7 days of insertion. Six (0.9%) of these had completed their purpose and had not failed; these were not included in the study. Of the 46 catheters having early failure, six (0.9%) were clotted and 12 (1.9%) were suspected of being infected, only three of which had a proven catheter-related infection. Twenty-eight catheters (4.4%) were removed for other reasons. In this group, the most common reasons were poor tip position (n = 9) and catheter replacement over a guidewire into a preexisting fibrin sheath (n = 8). Only two failed because of poor tip orientation. Other reasons for failure were kinked or pinched catheters (n = 4) and bleeding (n = 3), including one exsanguination, and two unknown reasons.

CONCLUSION

By paying careful attention to catheter tip position, searching diligently for the presence of a fibrin sheath when catheter exchanges are made over a wire, and better investigating presumed catheter infection, we could reduce the early failure rate by more than half, from 46 cases to 20 cases (nine cases of suspected infection were in fact not infected).

Stripping of failing haemodialysis catheters using the Ampltaz gooseneck snare

The development of a fibrin sheath at the tip of a long-term haemodialysis catheter may lead to deteriorating blood flow rates, resulting in inadequate haemodialysis. Restoration of functional patency has been described using the technique of percutaneous fibrin sheath stripping (PFSS) using a wire snare device. Our purpose was to assess this technique within an established renal vascular access service. All catheters referred for the assessment of low blood flow rates on dialysis were considered for the procedure. Initial fluoroscopic assessment of the catheter was followed by stripping of the tip of the catheter using a gooseneck snare. Seventeen of 22 well-positioned catheters undergoing a single PFSS attempt were restored to function with a median prolongation of patency of 4.25 months. Two catheters underwent a second PFSS procedure providing additional patency. Nineteen of a total of 24 (79%) PFSS procedures successfully restored catheter function. Seven catheters with poorly positioned tips or a kink were not restored to functional patency using PFSS. Two patients developed a puncture site haematoma. No patient developed symptoms of pulmonary emoblism. In conclusion, PFSS restored function in 79% of attempts in well positioned catheters. The method is technically straightforward, with a low complication rate and has become a routine part of the renal vascular access service.

Successful Long-Term Central Venous Access; Daily Home Hemodialysis Blood Access

Successful long-term central venous access is a complex subject. The concept of "long term" implies that continued surveillance will be required. This also requires the catheter to be placed, initially, in its best configuration. To achieve long-term performance and durability, a thorough understanding of all aspects related to the catheter, catheter placement, and catheter maintenance is essential.

Catheter malfunction and thrombus formation on double-lumen hemodialysis catheters: an intravascular ultrasonographic study

Intravascular ultrasound imaging (IVUS) is a new method that permits in vivo visualization of central venous catheters with hitherto unknown image resolution. It provides information not only about thrombus formation, but also about catheter movement, catheter malposition, and vessel wall injuries. In the present investigation the method was applied to evaluate the frequency of thrombus formation on double-lumen hemodialysis catheters and its significance for catheter malfunction. In 14 patients who had a double-lumen hemodialysis catheter for temporary or long-term vascular access, IVUS of the catheter and the mediastinal vein stems was performed. Mean indwelling duration at the time of the ultrasound investigation was 101 days (range. 3 to 730 days; median, 58 days). Four patients had catheter-related thrombotic complications: IVUS failed to detect an intracatheter thrombus in one case; a catheter thrombus and superior vena cava stenosis were found in a catheter with normal function in one case; in one case with catheter malfunction, a combined catheter-mural thrombus was found; and in the remaining case, a catheter thrombus and a mural superior vena cava thrombus were found in a patient with normal catheter function and pulmonary emboli. Thus, two of 12 patients with well-functioning catheters (16%) had thrombotic complications demonstrated by IVUS, and one of two patients with catheter malfunction had thrombus identified by IVUS. It is concluded that thrombus formation is less likely in patients without signs of catheter malfunction.(ABSTRACT TRUNCATED AT 250 WORDS)