Ash Split Catheter Research Articles

Abstract No. 29 Tunneled Dialysis Catheter Placement within Intensive Care Unit (ICU) Patients: Influence of Catheter Tip Design on Clinical Performance

Tunneled dialysis catheter tip design may affect freedom from catheter dysfunction and/or infection; improved performance within a critical care setting may reduce costs and need for catheter guidewire exchange or removal. This study compared rates of catheter failure between a symmetrical, helical-tip catheter (VectorFlow) with a conventional split-tip catheter (Ash-Split) among ICU patients undergoing tunneled dialysis catheter placement. A retrospective database identified a total of 1734 tunneled dialysis catheters placed at an academic institution over a 7-year period. Of these, 340 catheters (19.6%) were placed within ICU patients, which included VectorFlow (n = 112, 32.9%) and Ash-Split (n = 228, 67.1%) catheters. Rates of catheter failure requiring guidewire exchange or removal from a composite outcome of malfunction or infection were compared with Kaplan-Meier estimates, and covariates potentially influencing catheter failure were assessed with Cox proportional hazards modeling. Catheter failure occurred within 90 days in 34.8 ± 3.4% of ICU patients. Among patients with VectorFlow catheters, primary unassisted patency at 30, 60, 90 and 180 days was 87.4 ± 3.6%, 78.0 ± 5.1%, 75.1 ± 5.0% and 60.1 ± 8.2% compared with 75.0 ± 3.3%, 62.8 ± 4.1%, 60.7 ± 4.2% and 44.3 ± 5.5% among patients with Ash-Split catheters (P = 0.022). Cox modeling of body mass index, patient age, sex, left jugular (vs. right) placement and indication for placement (initiation of hemodialysis access vs. failed surgical arteriovenous access) showed no effect on catheter patency; patients with Ash-Split catheters had a hazard ratio of catheter failure 1.72 times higher than patients with VectorFlow catheters (P = 0.024) in univariate modeling and a hazard ratio of 1.81 in multivariate modeling (P = 0.017). The VectorFlow catheter was associated with significantly higher rates of primary patency than the Ash-Split catheter among ICU patients, independent of multiple clinical and anatomic factors. These data support a VectorFlow-first placement strategy within this patient population.

Cavo-atrial endocarditis: A case of non-valvular endocarditis in a hemodialysis patient.

The incidence of infectious endocarditis (IE) is significantly higher for patients who are on chronic hemodialysis (HD) compared to the general population for a number of reasons [1]. Even with a higher incidence, right sided, specifically cavo-atrial, endocarditis is extraordinarily rare [2,3]. This case examines a 54 year old male with end stage renal disease (ESRD) who was receiving HD with an Ash Split Catheter and was subsequently diagnosed with cavo-atrial endocarditis.

Measuring of the heparin leakage into the circulation from central venous catheters--an in vivo study

A catheter lock with a highly concentrated heparin solution is often used to maintain its patency. The result of the in vitro study shows a significant catheter leakage that occurs after locking the catheter. The goal of this study is to develop a model to measure the catheter leakage in vivo and test it on various kinds of catheters. Twenty-four patients with central venous dialysis catheters were examined. After the 48-h interdialytic period, we aspirated the contents of the catheter lumen for analysis. We simultaneously took a sample of the peripheral blood for analysis. In the second part of the test, instead of taking the sample after 48 h, we took it after 10 min. Based on the difference in haematocrit in those two samples, we were able to determine the amount of heparin that remained in the catheter, and indirectly, the amount of heparin that leaked out of the catheter. Using the lock volumes indicated on the catheter by the manufacturer, the early leakage is significantly higher in nontunnelled catheters compared to tunnelled Hemoflow and Ash Split catheters (P = 0.05). There is no significant statistical difference in the early leakage between Ash Split and Hemoflow catheters. The late leakage is significantly higher in nontunnelled catheters compared to Hemoflow and Ash Split catheters (P = 0.05). There is no significant statistical difference in the total leakage between Ash Split and Hemoflow catheters. We present a model that enables the measurement of the catheter leakage in vivo. We applied the model on three kinds of catheters and concluded that both early and late leakages are significantly higher in nontunnelled catheters compared to Hemoflow and Ash Split tunnelled catheters. Our results show that the so-called early leakage measured in vivo is significantly lower compared to the results from in vitro studies. Further research is necessary to determine the amount of leakage volume for different kinds of catheters and to determine the exact leakage dynamics of lock solutions in vivo.

Do AshSplit Haemodialysis Catheters Provide Better Flow Rates in the Long Term?

Background. Recently, interventional radiologists have adopted an increasingly prominent role in the placement and management of hemodialysis catheters, as well as in the research and development of new and better catheters. The purpose of this study was to evaluate the viability and hemodialysis efficiency of the AshSplit catheter and the Permcath catheter. Methods. 204 consecutive patients requiring radiological insertion of hemodialysis catheters were followed, retrospectively, over a 42-month period. Both hemodialysis catheters were placed using a combination of ultrasonic and fluoroscopic guidance and tunneled appropriately. Information collected included catheter insertion sites, insertion complications, catheter duration, and final outcome. Results. Over the study period of two years, 269 catheters were placed into 204 patients with end stage renal failure. Patients received either an AshSplit (101 patients, 127 catheters) or a Permcath (103 patients, 142 catheters). Vascular access route of choice was the right internal jugular vein (67% AshSplit, 71% Permcath). Insertion complications occurred in 18 patients overall (6.6%), with only 1 requiring further intervention (hemopneumothorax). Flow rates averaged 259 mls/min for AshSplits and 248 mls/min for Permcaths (p < 0.001). Follow-up of catheter viability for 42 months yielded a mean AshSplit catheter duration of 246 days (range 6–932) and 239 days (range 1–1,278) for Permcath (p = 0.46). Reasons for catheter failure and elective catheter removal were similar in both groups; however, Permcaths required significantly more thrombolysis than AshSplits, p < 0.001. Conclusion. The AshSplit provides significantly better flow rates and less thrombolysis compared to the Permcath, with similar catheter dwell times.

EVALUATION OF INTERNAL JUGULAR VEIN THROMBOSIS IN DIALYSIS PATIENTS WITH LARGE TUNNELED CATHETERS.

Purpose To evaluate the prevalence of internal jugular vein thrombosis in patients with large diameter (16 French) tunneled dialysis catheters to determine if the larger diameter catheters are associated with increased thrombosis rates. Methods and Materials A retrospective chart review of dialysis-dependent end-stage renal disease patients at the Memphis VAMC was performed to identify patients who had received tunneled internal jugular catheters for hemodialysis. Since 2002, large-diameter, 16 French Ash-Split catheters have been primarily used. Eligible patients were those with 16 French catheters placed from January 1, 2002, to October 1, 2006. A total of 60 patients were identified. Additional information obtained from patient records included catheter site placement, number of catheters placed in each site, history of hypertension, history of diabetes mellitus, and number of catheter-related infections. Results All of the 60 patients were men. A diagnosis of hypertension was present in 85% (51 of 60) and diabetes mellitus was present in 35% (21 of 60). These percentages are similar to the overall prevalence of hypertension and diabetes mellitus seen in ESRD patients at this center. In 7 of the 60 patients in the study, bilateral internal jugular veins were used for tunneled catheter placement; thus, the total number of access sites was 67. Thrombosis was present in 16.4% (11 of 67) of the total number of catheter access sites. Of the total number of thromboses present, 63.6% (7 of 11) were in the right internal jugular vein and 36.4% (4 of 11) in the left internal jugular vein. Also, of the 11 thromboses present, 82% (9 of 11) of the occlusions were associated with catheter-related infections. Conclusion Previous studies have reported the prevalence of internal jugular thrombosis in patients with standard dialysis catheters (14.5 French) to be around 10 to 25%. The prevalence of thrombosis demonstrated in this study shows no increased rate of thrombosis with larger catheters. There was an extremely high frequency of catheter-related infections in patients with thrombosis.

Neonatal Hemodialysis and Continuous Renal Replacement Therapy

After completing this article, readers should be able to: 1. Describe catheters, dialyzers, and blood lines in hemodialysis for neonates. 2. Explain the blood prime and hemodialysis prescription in hemodialysis for neonates. 3. List potential complications of hemodialysis for neonates. 4. Identify the types of continuous renal replacement therapy (CRRT) in neonates. 5. Explain the dialysis prescription and anticoagulation options for CRRT in neonates. 6. List potential complications of CRRT in neonates. Since the mid-1980s, when dialysis manufacturers began making dialyzers and blood circuit paths that required smaller extracorporeal volumes, hemodialysis has been used successfully to manage renal failure in neonates and infants. Compared with peritoneal dialysis (PD), which is analogous to the “family sedan” in the world of dialysis (slower, more predictable, easier to operate), hemodialysis is the “race car.” Hemodialysis is capable of removing fluids and solutes much more rapidly than is PD. Unlike PD, hemodialysis uses catheters that access the intravascular space directly. Despite the advantages of hemodialysis, the process in neonates is technically more challenging than PD due to the very attributes that make it so effective. Rapid removal of intravascular fluids, exceeding the rate of refill from the extravascular space, causes problems with hypotension due to direct reduction in intravascular volume. Similarly, rapid rates of solute clearance can cause problems with increased intracranial pressure. Catheter placement and maintenance of catheter function can constitute a significant obstacle to hemodialysis. Hemofiltration is very similar to hemodialysis in that patient blood is circulated through an artificial kidney. However, hemofiltration differs from hemodialysis in three significant aspects. First, the hemofilter has larger pore sizes than the standard dialyzer, which allows for excellent fluid removal, even with low blood flow rates, and better larger molecule clearance. Second, hemofiltration runs continuously without the continuous presence of a dialysis nurse. Third, typical hemofiltration uses a pre- or postdilution …

A Prospective Comparison of Two Types of Tunneled Hemodialysis Catheters: The Ash Split Versus the PermCath

In a prospective randomized study a standard dual-tip hemodialysis catheter (PermCath, Sherwood Medical, St. Louis, MO, USA) was compared with a newer split-lumen catheter (Ash Split, Medcomp, Harleysville, PA, USA). Sixty-nine patients (42 men, 27 women; mean age 62 years) were randomized to receive either the Ash Split (AS) or the PermCath (PC) catheter. The catheters were inserted into the internal jugular vein. The primary outcome evaluated was blood flow measurements during the first six hemodialysis sessions. Secondary outcomes included: technical difficulties encountered at insertion, early complications and late complications requiring catheter removal or exchange. A total of 69 hemodialysis catheters, 33 AS and 36 PC, were successfully inserted in the internal jugular vein (right 60, left 9) of 69 patients. Mean blood flow during dialysis (Qb) was 270.75 ml/min and 261.86 ml/hr for the AS and PC groups respectively (p = 0.27). Mean duration of catheter use was 111.7 days (range 5.4-548.9 days) and 141.2 days (range 7.0-560.9 days) in the AS and PC groups respectively (p = 0.307). Catheter failures leading to removal or exchange occurred in 20 patients: 14 in the AS group and six in the PC group. Survival curves with censored endpoints (i.e., recovery, arteriovenous fistula formation, peritoneal dialysis and transplantation) showed significantly better outcome with PermCath catheters (p = 0.024). There was no significant difference in ease of insertion or early complication rates. The Ash Split catheter allows increased rates of blood flow during hemodialysis but this increase was not significant at the beginning (p = 0.21) or end (p = 0.27) of the first six hemodialysis sessions. The Ash Split catheter is more prone to minor complications, particularly dislodgment, than the PermCath catheter.

Salvage Insertion of Tunneled Central Venous Catheters in the Internal Jugular Vein after Accidental Catheter Removal

Tunneled catheters are widely used for intermediate to long-term hemodialysis (HD) access, but are prone to several complications that can require catheter replacement. Replacing malfunctioning catheters with a new line, placed in a different access site, can lead to problems with multiple vein occlusions. This has led many nephrologists to continue using the same vein as long as possible by guidewire catheter exchanges, to preserve other veins for future use. We describe a guidewire exchange technique for the Ash-Split catheter in the internal jugular vein. In three patients, the exchange was performed because of partial catheter removal, as evidenced by the outward dislocation of the Dacron cuff. In these patients, the guidewire was inserted through the catheter. In two additional patients, the catheter had been completely removed by accident: the replacement of the dislodged tunneled venous catheters was attempted 5 hr and 1 day after accidental removal. In these patients, the guidewire was inserted through the previous tunnel. After guidewire placement, a skin incision was made in the supraclavicular region. The metal guidewire was easily located inside the fibrous structure that had previously surrounded the catheter. The guidewire was then extracted from the subcutaneous tunnel and used to insert a new catheter safely and easily after creating a new tunnel. Patients were routinely given antibiotic prophylaxis (1 g of cefazolin) immediately before the procedure. A strict aseptic technique was used, including several sterile glove changes. No infections developed following this procedure, which has the potential for bacterial contamination. All procedures were successful. Only in one patient did we have to convert to a different catheter: it was not possible to replace the old Ash-Split catheter with the same dual-lumen catheter because of difficulties in inserting the peel away introducer-catheter complex. In this patient, rather than forcing it with larger dilators or trying to disrupt the fibrin sheath with balloon dilatation, a single lumen Tesio catheter was successfully placed. In both patients who completely lost the previous catheter, the guidewire was readily reinserted through the subcutaneous tunnel into the vein. Catheter function was excellent in all patients, with a test blood flow rate on the 1st catheter use >350 ml/min. We described a new method for catheter exchange, which allows the easy insertion of a new catheter and the creation of a new and safer subcutaneous tunnel. In addition, we demonstrated that in cases of complete catheter removal, it is possible to reinsert a catheter in the same vein through a guidewire, even when reinsertion was attempted up to 1 day later.

Central Venous Catheter Access in Children on HD

Central venous catheters (CVC) remain a frequently used form of vascular access in children receiving chronic hemodialysis (HD). Whereas standard dual‐lumen catheters (DL) are used in many centers, the Tesio catheter has proven to be superior to the DL catheter in terms of catheter survival and infection rates in at least one pediatric study (Sheth RD et al. Am J Kidney Dis. 2001). Recently, the Ash Split catheter became available which, while similar to the Tesio internally, being comprised of 2 separate catheters, may be preferable because of the requirement for only one skin puncture for placement vs. two for the Tesio. However, no pediatric data pertaining to the Ash Split catheter have been published to date. Therefore, we reviewed and compared our experience with a small number of Ash Split (# 16) and Tesio (# 8) catheters used for semipermanent vascular access in our chronic HD population with reference to survival, infectious complications, patency, and dialysis adequacy. The results of this experience are as follows: Tesio Ash Split Survival &gt;3 months 6/8 12/15 Sepsis (epi/catheter mo) 1/30 1/25 Exit‐site infection (epi/catheter mo) 1/8.6 1/19 sp Kt/V urea 1.67 1.88 % sp Kt/V urea &gt;1.2 100 90 Reasons for the removal of Tesio catheters were transplant (4), sepsis (1), deterioration of tubing (1), and accidental (1). Ash Split catheter removal resulted from sepsis (2), fistula placement (4), thrombosis (1), and accidental (2). This preliminary experience reveals similar outcome data for the Tesio and Ash Split catheters when used in pediatric HD patients. Definitive statements regarding the superiority of either catheter awaits additional data collection and analysis.

Radiological placement of the AshSplit haemodialysis catheter: a prospective analysis of outcome and complications.

The AshSplit catheter has recently been introduced as an alternative permanent tunnelled haemodialysis catheter, combining ease of insertion with good long-term patency and flow rates. Data were collected prospectively on all the long-term tunnelled haemodialysis (AshSplit) catheters inserted radiologically between January 1998 and March 1999. Information was obtained regarding the initial insertion, ongoing catheter function and re-intervention up to September 1999. A total of 118 catheters were inserted in 88 patients (50 male), median (range) age 64 (20-86) years. Ultrasound guidance was used routinely and the right internal jugular vein was used in 80 (68%) cases. Initial complications occurred in 14 (11.9%) cases, which included local haemorrhage, carotid artery puncture, and air embolism. Infection occurred in 34% of catheters (2.4/1000 catheter days). Line thrombosis was documented in 20% (1.2/1000 catheter days). Satisfactory mean urea reduction ratio (URR) of 63 was obtained for all catheters. There were 47 re-interventions, mainly for fibrin sheath stripping (34) and/or thrombectomy (25). Total catheter duration was 21600 days with a 1 month cumulative survival of 87% (Kaplan-Meier probability 85%). At the end of the study, 20 (17%) catheters were still functioning, 39 (33%) had been removed electively, and 22 (18%) patients had died with a functioning catheter in situ. Catheter infection was implicated in four deaths. Radiological insertion of the AshSplit catheter is well tolerated, providing reliable short- and long-term dialysis access. Radiology also has a role in maintaining patency. As with all tunnelled catheters, infection remains a problem.

A Randomized, Prospective Evaluation of the Tesio, Ash Split, and Opti-flow Hemodialysis Catheters

A randomized, prospective evaluation of three high-flow hemodialysis catheters. Ninety-four patients were randomly assigned 113 Tesio, Ash split, and Opti-flow catheters from December 1998 through June 1999. Insertion times, procedural complications, and ease of insertion were recorded. Mean catheter flow rates were recorded at first dialysis, 30 days, and 90 days. Patency, catheter survival, and catheter-related infections were evaluated. Thirty-eight Ash split, 39 Opti-flow, and 36 Tesio catheters were placed. Tesio mean insertion time (41.5 min) was significantly longer than Ash split (29.4 min) or Opti-flow (29.6 min) (P =.004). There were four complications related to Tesio catheters (three cases of pericatheter bleeding, one air embolism), one related to an Opti-flow catheter (pericatheter bleeding), and zero related to Ash split catheters. Opti-flow and Ash split catheters were significantly easier to insert than Tesio catheters (P =.041). Mean flow rates were not significantly different among the catheters initially (P =.112), at 30 days (P =.281), or at 90 days (P =.112). Catheter-related infection rates per 100 catheter days were 0.12 for Ash split, 0.35 for Opti-flow, and 0.14 for TESIO: Median catheter survival was 302 days for Ash split, 176 days for Opti-flow, and 228 days for TESIO: Opti-Flow and Ash split catheters were faster and easier to place than Tesio catheters. There was no difference in hemodialysis flow rates or catheter survival.

Accidental Migration of ASH-Split Catheter during Central Venous Catheter Replacement: Retrieval using an Interventional Radiology Approach

Catheter fracture and embolization of the distal fragment are well-known complications of subclavian central venous long-term cannulation. In hemodialysis it is an exceptional event. We report a case of accidental rupture of a cuffed hemodialysis catheter with distal migration of a fragment during a procedure of catheter exchange via guide-wire. According to most reported cases, intravascular catheter separation usually occurs completely asymptomatically; our report confirms that catheter embolization itself is usually asymptomatic. Less than one third of the literature-reported cases have associated symptoms, such as palpitations or chest discomfort. Once diagnosed, treatment is an interventional radiological approach, which has a very high success rate. The replacement of permanent cuffed hemodialysis catheters via guide-wire is a delicate procedure and if catheter embolization is diagnosed, the patient must be referred to a center with specific experience in the retrieval of intravascular objects.