Using cuffed and tunnelled central venous catheters as permanent vascular access for hemodialysis: a prospective study

Removal of stuck tunnelled dialysis line requiring cardiopulmonary bypass and venous repair

Tunnelled central venous dialysis catheters can usually be removed easily. However, their removal can become rarely complicated requiring more invasive techniques. We report a case in which cardiopulmonary bypass and repair of great veins was required for safe removal. A 38-year-old female with end-stage renal failure and a 3-year-old Hickman line inserted into her right internal jugular vein was referred to our cardiac surgical unit following failed attempts of line removal by local vascular surgical team using open vascular surgical techniques. As a result, an MDT decision was made that it was safer to proceed to a cardiothoracic surgical approach rather than other techniques. Investigations showed significant calcification surrounding the line which was adherent to the venous wall. Removal of the retained catheter required median sternotomy and the use of cardiopulmonary bypass as the great veins had to be opened to free the line and allow complete removal. The line was successfully removed with its encircling calcified sheath, and the veins were closed primarily without needing a patch repair. The integrity of the great veins was maintained to meet the on-going need this young patient has for central venous access. The patient made an uneventful recovery. When other measures fail, sternotomy and cardiopulmonary bypass provide a safe option for complete removal of stuck central venous catheters with low risk to the patient.

Low Posterior Internal Jugular Vein Approach for Tunnelled Haemodialysis Catheter Insertion: A Report on Outcomes at a Single Centre

AIM

The impact of technical differences in cannulation technique for tunnelled haemodialysis catheter insertion is undetermined. We aimed to assess clinical outcomes of the low posterior approach for internal jugular vein tunnelled catheter placement.

METHODS

A retrospective audit was undertaken on consecutive tunnelled catheter procedures performed at a single centre between January 2016 and June 2022. Only catheters specifically placed with a low posterior internal jugular approach were included. The study's primary outcome was 12-month catheter survival, evaluated using the Kaplan-Meier survival curve and log-rank test. Secondary outcomes included catheter performance and procedure-related complications.

RESULTS

During the study period, 391 tunnelled internal jugular haemodialysis catheters were inserted in 272 patients using the low posterior technique. The 12-month primary patency rate was 68%. Catheter insertion was successful in 96% of cases. Peri-procedural complications occurred in 4% of cases, most frequently bleeding. The most common reasons for catheter loss were dysfunction (10%) and bacteraemia (6%). The best predictors of catheter failure were advanced age (HR 1.02, 95% CI 1.00-1.04) and in-centre dialysis treatment locality (HR 2.04, 95% CI 1.19-3.45).

CONCLUSION

The low posterior approach for internal jugular vein tunnelled catheter insertion is effective and safe. We demonstrated a 12-month catheter survival rate of 68%. Further research comparing the low posterior approach with other internal jugular vein cannulation techniques is warranted.

Vascular access challenges in hemodialysis children

BACKGROUND

Hemodialysis (HD) success is dependent mainly on vascular access (VA). The aim of this study is to share the experience of Pediatric Nephrology Unit (PNU), Cairo University Children's Hospital (CUCH), with VA-related obstacles in end stage kidney disease (ESKD) HD children.

METHODS

This is a retrospective analysis of VA related data of 187 ESKD children received regular HD over 3 year duration (2019-2021). Kaplan-Meier curves were used to present arteriovenous fistula (AVF) and cuffed catheters survivals.

RESULTS

Uncuffed central venous catheter (CVC) was the primary VA for HD in up to 97.3% with 2.7% of patients had AVF performed and attained maturation before initiation of regular HD. Fifty-six (29.9%) patients have inserted 120 tunneled CVCs. AVFs & AV grafts (AVF) were performed in 79 (42.2%) and 6 (3.2%) patients respectively. There were 112 uncuffed CVCs implanted beneath the screen in Rt internal jugular vein (IJV) (44%) Lt IJV (17%), right internal mammary vein (2.7%) while Trans hepatic (TH) technique was used to place 39 uncuffed CVCs (34%) in the inferior vena cava (IVC). Catheter-related bacteremia (CRB) was the most frequent complication in uncuffed and cuffed CVCs (2.58 / 100 catheters day and 10.1 /1000 catheter days respectively). AVFs achieved a high success rate (83%) after 757.71 ± 512.3 functioning days.

CONCLUSION

Native AVF is the preferred VA for pediatric HD but its creation is limited by the small sized vessels where non-cuffed CVC could be a reasonable relatively long-term alternative. Challenging situations (occluded central veins) could benefit from TH technique of CVC insertion in IVC.

[Endoluminal balloon dilatation of impacted central venous catheter-Case report and literature review]

BACKGROUND

The long-term application of tunneled central venous catheters leads to the development of firm adhesions between the wall of the vein and the catheter, which makes removal of the catheter difficult or impossible. The treatment options in such cases include abandonment of catheter parts or an open surgical approach up to sternotomy. At present, procedural alternatives are available, which include endovascular techniques such as the use of laser energy and endoluminal dilatation.

METHODS

This article describes the successful application of endoluminal dilatation for removal of ingrown central venous catheters in three patients, which had impacted in the superior vena cava and brachiocephalic vein. A 5 Fr (Cordis, Santa Clara, CA, USA) sheath was inserted into one lumen through the severed end of the double lumen catheter. Subsequently, a balloon catheter was inserted into the other lumen to prevent retrograde bleeding or air embolism. Under fluoroscopy a guidewire (0.018, Terumo Medical Corporation, Somerset, New Jersey, USA) was introduced via the sheath to beyond the tip of the hemodialysis catheter into the right atrium. Finally, an angioplasty balloon was inserted (4 × 80 mm) via the guidewire and the complete catheter was sequentially inflated with a pressure of 4 atm. It was then possible to pull out the catheter with no difficulty.

RESULTS

This technique resulted in the removal of the central venous catheters in all three patients, without any relevant complications or resistance.

CONCLUSION

By dissolving adhesions between the catheter and the vein wall, endoluminal balloon dilatation constitutes a reliable and safe technique for the extraction of impacted central venous hemodialysis catheters and may thus help to avoid further invasive surgical procedures.

Efficacy and Safety of Bedside Removal of Tunnelled Hemodialysis Catheter by Noninterventional Nephrologists among Adult Patients in the King Abdulaziz University Hospital Hemodialysis Centre in Jeddah: A Retrospective Cohort Study

This study aimed to assess the efficacy and safety of bedside removal of tunnelled hemodialysis catheter (TDC) by noninterventional nephrologists among adult patients. It is a retrospective study that involved 53 patients from March 2020 to February 2022 at the King Abdulaziz University Hospital (KAUH) Hemodialysis Centre in Jeddah, Saudi Arabia. Of the 53 participants, 60.4% were male and 40.6% female, and their mean age was 50.94 ± 18.89 years. The most common comorbidities were hypertension (HTN) in 47 (88.7%), diabetes mellitus (DM) in 24 (45.3%), and DM and HTN together in 23 (43.4%) patients. The most common site of TDC removal was the right internal jugular vein (77.4%). In 84.9% of the cases, the TDC was removed as an inpatient procedure, and in the majority of the cases (64.2%), the TDC was removed by a noninterventional nephrologist. The most common reasons for TDC removal were sepsis or clinical concerns for infection (64.2%) and TDC not needed (20.8%) due to recovery of the renal function or access maturation. Most patients (96.2%) suffered no complications; only one of 34 (%) patients with catheter removal by a noninterventional nephrologist had bleeding, which required more observation and monitoring before discharge on the same day. Our study revealed that the bedside TDC removal was well tolerated with a minimal complication rate.

Deeper may not be better: relationship between catheter dysfunction and location of the catheter tip in right-sided tunnelled haemodialysis catheters

AIM

To examine the relationship between catheter tip location and catheter dysfunction in the context of tunnelled central venous catheters (CVCs) for haemodialysis.

MATERIALS AND METHODS

This was a retrospective study of 993 haemodialysis patients who underwent insertion of tunnelled CVCs of step-tip design via the right internal jugular vein (IJV). Based on intra-procedural radiographs, the catheter tip was characterised as being in the superior vena cava (SVC), cavo-atrial junction (CAJ), or deep right atrium (DRA). Patients were tracked for 90 days post-procedure for complications resulting in catheter replacement, and these were compared between cohorts. Statistical analysis was performed with Pearson's chi-square and Fisher's exact tests for categorical variables and two-sample t-test and one-way analysis of variance (ANOVA) for continuous variables.

RESULTS

Ninety-five patients (9.6%) experienced catheter dysfunction necessitating replacement within 90 days of insertion. Tip location in SVC was associated with lower occurrence of catheter dysfunction (1.9%) as compared with the CAJ (8%) and DRA (11%; p=0.049). Catheter replacement due to other complications (catheter-associated bacteraemia, cuff dislodgement, exit-site infection, external catheter damage) showed no statistically significant relation to location of the CVC tip.

CONCLUSION

When utilising tunnelled CVCs with a step-tip design inserted via the right IJV, location of the catheter tip in the SVC is associated with reduced occurrence of catheter dysfunction as compared to either the CAJ or DRA.

Placement of tunneled cuffed catheter for hemodialysis: Micropuncture kit versus Angiocath IV catheter

INTRODUCTION

Tunneled cuffed catheters provide stable, instantaneous, long-term intravenous access for hemodialysis. Because catheterization is often performed in emergency situations, speed and accuracy are emphasized.

METHODS

We retrospectively compared the Micropuncture kit with the standard 18-gauge Angiocath IV catheter for tunneled cuffed catheter insertion in the right jugular vein. From June 2016 to May 2017, 31 tunneled cuffed catheters were successfully inserted via the Micropuncture kit and another 31 via the Angiocath IV catheter. All patients underwent the same ultrasound-guided procedure performed by a single experienced interventionalist. Procedure time was the time from draping of the patient to the completion of povidone dressing after the catheterization. In our center, the Angio Lab nurse maintains records, including procedure time and method for every procedure. All patient records were retrospectively tracked through electronic medical record review. The primary outcome was procedure time and the secondary outcomes were complications and cost-effectiveness.

RESULTS

There were no significant differences in the patients' demographic data between the two groups. However, procedure time was significantly shorter in the Angiocath group than in the Micropuncture group (12.4 ± 3.5 vs 17.6 ± 6.9 min, p = 0.001); there were no serious complications, such as hemorrhage, pneumothorax, or hematoma, in both groups. Moreover, cost-effectiveness was better in the Angiocath group than in the Micropuncture group (0.34 vs 52 US$, p < 0.01).

CONCLUSIONS

Using the Angiocath IV catheter can reduce procedure time and cost with no severe complications. Moreover, experienced practitioners can reduce the risk of complications when using Angiocath. There are several limitations to this study. First, it was retrospective; second, it was not randomized; and finally, it was conducted by only one experienced interventionalist.

The Vascular Access Questionnaire: Assessing Patient-Reported Views of Vascular Access

Background

The use of central venous catheters for vascular access in hemodialysis (HD) patients is associated with an increased risk of complications compared to arteriovenous fistulas (AVF). Despite this, catheter use remains high and patient satisfaction may be an important driver of catheter use.

Methods

We developed the Vascular Access Questionnaire (VAQ) to measure patient-reported views of their vascular access. Chronic HD patients at two centers were asked to rate how bothered they were by 17 access-related problems. VAQ symptom scores were compared between patients using catheters and those using fistulas for vascular access.

Results

Two hundred and twenty-two patients were eligible for the study. Symptom score was not different between patients using catheters and those using fistulas (p=0.36). However, patients using fistulas were more likely to be at least moderately bothered by pain, bleeding, bruising, swelling, and the appearance of their access than patients using catheters. Elderly patients reported lower symptom scores with catheters than fistulas.

Conclusions

Patients appear to be primarily concerned with the appearance of their access and cannulation-related complications, particularly the elderly. Better education about the risk of adverse events with catheters and the implementation of measures aimed at reducing cannulation-related complications may help to increase fistula rates and improve patient satisfaction with their vascular access.

A Novel Catheter System for Totally Implantable Intravenous Drug Therapy: Assessment of Catheter Function and Patency with Trepostinil Therapy

Background

Catheter failure, either due to dislodgment, occlusion or infection is the leading complication of chronic intravenous drug therapy. Better drug delivery techniques are required to advance life saving therapies that require this delivery method. This study evaluated the chronic performance of a fully implantable drug delivery system that incorporates a novel intravenous catheter. The system was designed to reduce complications associated with intravascular drug delivery including catheter occlusion, breakage, migration, and infection.

Methods

Twelve canines were implanted with a novel central venous catheter (Model 10642; Medtronic, Minneapolis, MN) connected to a totally implanted programmable drug pump (Model 8637 SynchroMed II®, Medtronic). The drug delivery systems infused saline (n=6) or treprostinil (n=6) (Remodulin®; United Therapeutics, Research Triangle Park, NC) for either 12 or 26 weeks at a continuous flow rate of 540 μL/day. Catheter performance was assessed at 0 (implant), 2, 4, 8, 12, 16, 20, and 24 weeks by quantifying delivery pressure, delivery volume and steady state Treprostinil concentrations.

Results

All catheters remained patent and free of complications for the duration of the study. Analysis of pressure waveforms during bolus delivery showed low and unchanged catheter resistance throughout the study. Measurement of pump delivery volume accuracy showed that the delivered volume was statistically similar to the calculated delivery (product of flow rate and elapsed time). Measurement of plasma treprostinil levels showed stable concentrations over the study period. There were no catheter dislodgments or breakage. Pathology showed all catheters free from fibrosis and thrombus and minimal changes to the vascular endothelium.

Conclusions

The Model 10642 vascular catheter along with the SynchroMed II implantable drug delivery system showed promising performance in a chronic animal model.

Predicting tissue plasminogen activator use and success in in-center hemodialysis patients

INTRODUCTION

Hemodialysis catheter malfunction is problematic. We aimed to determine clinical, catheter, and hemodialysis variables that predict: (i) catheter malfunction requiring recombinant tissue-plasminogen activator (TPA) treatment and (ii) the success of TPA administration.

METHODS

Clinical, catheter, and hemodialysis variables were collected from a cohort of 559 catheters (141,526 catheter days) in 175 hemodialysis patients (2008-2011). Time to, and predictors of, catheter malfunction were determined for all catheters and primary catheters only, analyzed by Cox-proportional hazard model, multi-variable logistic regression model, and mixed-effect logistic regression models. Success of TPA use was determined immediately, next day, and two weeks after use.

RESULTS

Shorter time to first TPA administration in all patient's catheters was associated with increased body mass index (hazard ratio [HR] = 1.06, 1.01-1.11, p = 0.03) and being of black race (HR = 3.05, 1.65-5.67, p<0.01). Primary TPA administration success at two weeks among primary catheters was associated with increased mean peak venous pressure before TPA administration (odds ratio [OR] = 1.03, 1.01-1.06, p<0.01) and decreased mean of the lowest systolic blood pressure measure for the three dialysis sessions prior to TPA administration (OR = 0.95, 0.91-0.99, p = 0.02). TPA administration success at two weeks among all catheters was associated with decreasing body mass index (OR = 0.84, CI 0.73-0.96, p = 0.01) and having diabetes (OR = 7.19, 1.40-36.81, p = 0.02).

CONCLUSIONS

Both patient and dialysis predictors of TPA use and success were identified in this study, which may be useful for fine-tuning catheter management protocols to target hemodialysis patients at high risk of catheter malfunction.

Deviations of Placement / Function of Permanent Central Vein Catheters for Hemodialysis

Fourteen cases of malposition of a permanent central vein catheter for hemodialysis or poor blood flow associated with thrombosed central veins but correct catheter positioning, in 13 patients suffering from end stage renal disease, presented from September 1991 to December 2003 among 385 permanent central vein catheters for hemodialysis (3.6%). There were 8 episodes of catheter tip malplacement in the azygos vein (1 case), hemiazygos vein (1), left internal thoracic (mammalian) vein (1), contralateral innominate vein (5) and 6 cases with correct anatomical catheter tip placement but with blood inflow from the catheter through the collateral vein system because of thrombosis of a major vein trunk (hemiazygos vein system (2), azygos vein (2), ascending lumbar veins (1), or portal vein system (1)). The malposition was diagnosed using roentgenography, with or without contrast, and computer tomography. In 3 cases the catheter was removed, in 5 cases the position was corrected. In the remaining 6 cases its function was maintained using anticoagulation or/and thrombolytic therapy. In conclusion, the placement of a permanent central vein catheter for hemodialysis must be followed by simple or contrast medium x-ray evaluation of its correct position or function. The malposition must be corrected whereas in the case where there is no alternative solution the function of the catheter may be maintained in the incorrect position using a combination of anticoagulation or/and thrombolytic therapy.

A stuck haemodialysis central venous catheter: not quite open and shut!

Removal of tunnelled central venous catheters can become complex if left in situ for a prolonged period. We report a challenging case of a stuck tunnelled haemodialysis catheter, which required sternotomy with cardio-pulmonary bypass for retrieval. A 47-year-old female had failed attempts to remove the venous limb of a Tessio line on the ward. A cut down on the internal jugular vein and division of the fibrin sheath failed to release it. Synchronous traction was applied via a snare inserted through a femoral approach. On table trans-oesophageal echocardiogram showed the tip of the catheter traversing the tricuspid valve. At sternotomy with cardio-pulmonary bypass, the tip of the catheter was found attached to the septal leaflet of the tricuspid valve requiring release and repair. The management of stuck line has potential serious complications. Prophylactic catheter exchange should be considered to avoid complications.

Transcutaneous intravascular transposition of a permanent dialysis catheter

Permanent catheters are used to provide long-lasting access for long-term dialysis therapy in certain patients when creating an arteriovenous fistula between their own vessels is not possible, when there are contraindications for fistula creation or when the expected lifetime of the patient is short. We present the case of a patient with terminal renal insufficiency treated with hemodialysis for 5 years. Due to post-thrombotic changes and venous stenosis resulting from long-term cannulation with dialysis catheters, the replacement catheter was inserted through the previously used canal and transcutaneous intravascular catheter transposition was performed.

Risk factors associated with hemodialysis central venous catheter malfunction; a retrospective analysis of a randomized controlled trial

Background

We previously reported a reduction in central venous catheter (CVC) malfunction when using once-weekly recombinant tissue-plasminogen activator (rt-PA) as a locking solution, compared with thrice-weekly heparin.

Objectives

To identify risk factors for CVC malfunction to inform a targeted strategy for rt-PA use.

Design

Retrospective analysis.

Setting

Canadian hemodialysis (HD) units.

Patients

Adults with newly placed tunnelled upper venous system CVCs randomized to a locking solution of rt-PA(1 mg/mL) mid-week and heparin (5000 u/ml) on the other HD sessions, or thrice-weekly heparin (5000 u/ml).

Measurements

CVC malfunction (the primary outcome) was defined as: peak blood flow less than 200 mL/min for thirty minutes during a HD session; mean blood flow less than 250 mL/min for two consecutive HD sessions; inability to initiate HD.

Methods

Cox regression was used to determine the association between patient demographics, HD session CVC-related variables and the outcome of CVC malfunction.

Results

Patient age (62.4 vs 65.4 yr), proportion female sex (35.6 vs 48.4%), and proportion with first catheter ever (60.7 vs 61.3%) were similar between patients with and without CVC malfunction. After multivariate analysis, risk factors for CVC malfunction were mean blood processed < 65 L when compared with ≥ 85 L in the prior 6 HD sessions (HR 4.36; 95% CI, 1.59 to 11.95), and mean blood flow < 300 mL/min, or 300 – 324 mL/min in the prior 6 HD sessions (HR 7.65; 95% CI, 2.78 to 21.01, and HR 5.52; 95% CI, 2.00 to 15.23, respectively) when compared to ≥ 350 mL/min.

Limitations

This pre-specified post-hoc analysis used a definition of CVC malfunction that included blood flow, which may result in an overestimate of the effect size. Generalizability of results to HD units where trisodium citrate locking solution is used may also be limited.

Conclusions

HD session characteristics including mean blood processed and mean blood flow were associated with CVC malfunction, while patient characteristics were not. Whether targeting these patients at greater risk of CVC malfunction with rt-PA as a locking solution improves CVC longevity remains to be determined.

The safety and efficacy of bedside removal of tunneled hemodialysis catheters by nephrology trainees

BACKGROUND

Some nephrologists remove tunneled hemodialysis catheters (TDC) at the bedside, but this practice has never been formally studied. Our hypothesis was that bedside removal of TDC is a safe and effective procedure affording prompt removal, including in cases of suspected infection.

METHODS

We reviewed our consecutive 3-year experience (2007-2009) with bedside TDC removal at the University of Mississippi Renal Fellowship Program. Data were collected on multiple patients and procedure-related variables, success and complication rates. Association between clinical characteristics and biomarkers of inflammation and myocardial damage was examined using correlation coefficients.

RESULTS

Of 55 inpatient TDC removals (90.9% from internal jugular location), 50 (90.9%) were completed without hands-on assistance from faculty. Indications at the time of removal included bacteremia, fever or clinical sepsis with hemodynamic instability or respiratory failure. All procedures were successful, with no cuff retention noted; one patient experienced prolonged bleeding which was controlled with local pressure. Peak C-reactive protein (available in 63.6% of cohort) was 12.9 ± 8.4 mg/dL (reference range: <0.49) and median troponin-I (34% available) was 0.534 ng/mL (IQR 0.03-0.9) (reference range: <0.034) and they did not correlate with each other. Abnormal troponin-I was associated with proven bacteremia (p < 0.05) but not with systolic and diastolic BP or clinical sepsis.

CONCLUSION

Our results suggest that bedside removal of TDC remains a safe and effective procedure regardless of site or indications. Accordingly, TDC removal should be an integral part of competent Nephrology training.

Imaging and management of complications of central venous catheters

Central venous catheters (CVCs) provide valuable vascular access. Complications associated with the insertion and maintenance of CVCs includes pneumothorax, arterial puncture, arrhythmias, line fracture, malposition, migration, infection, thrombosis, and fibrin sheath formation. Image-guided CVC placement is now standard practice and reduces the risk of complications compared to the blind landmark insertion technique. This review demonstrates the imaging of a range of complications associated with CVCs and discusses their management with catheter salvage techniques.

Repair of Damaged Connectors of Tunneled Cuffed Catheters with a Two-Piece Adaptor for Peritoneal Dialysis

Purpose

Although catheter use exposes the patient to several complications, tunneled cuffed catheters are widely applied for temporary or long-term vascular access. The aim of the study was to establish the rate of tunneled dialysis catheter damage and report our experience with breakage repair.

Methods

All 363 cuffed tunneled hemodialysis catheters inserted into 309 patients from May 2000 to December 2008 were followed up. When connector damage was encountered, repair with a two-piece adaptor for peritoneal dialysis was attempted.

Results

Mechanical breakage occurred in 33 (9.1%) of catheters with an incidence of 0.36/1000 catheter-days. The most frequent was connector damage, found in 25 cases (67.6%). Catheter repair using a peritoneal dialysis Luer adaptor was performed with good early and long-term outcome.

Conclusions

Tunneled catheter breakage is a relatively rare complication. Catheter repair using the adaptor for peritoneal dialysis is easy to perform, safe, and cost-effective.

Development of high-output heart failure after correction of central venous occlusion: a case report

Temporary or permanent central venous catheter (CVC) insertion has been performed frequently for hemodialysis treatment. One of the most important long-term complications of CVC is the central venous occlusion (CVO). Treatment of CVO consists of percutaneous angioplasty (PTA), PTA and stent implantation, or surgical procedure for resistant occlusions. Clinical outcome and long-term results of the revascularization procedures are well documented. However, there is no clear information about acute medical complications of the procedures. High-output heart failure (HOHF) is associated with several diseases including chronic anemia, psoriasis, systemic arteriovenous fistula, sepsis, hypercapnia, multiple myeloma, and hyperthyroidism. Herein, we report a case of chronic kidney disease with CVO that developed acute HOHF immediately after the revascularization procedure (PTA and stenting).

Two single-lumen noncuffed catheters in the jugular vein as long-term vascular access: a preliminary report

Two single-lumen, noncuffed catheters in the same jugular vein have been used as preferred vascular access in our hemodialysis (HD) and apheresis patients in past years. The aim of this retrospective study was to analyze the clinical outcome of such a vascular access and the reasons for catheter removal. In 129 adult patients, aged 69 ± 13 years, 56% males, treated by HD (121 patients) or apheresis (8 patients), two single lumen, pre-curved 8 Fr catheters (Medcomp, Harleysville, PA, USA) inserted into the same jugular vein were used as vascular access between January 2009 and April 2010. The catheters were inserted into the left jugular vein in 21 patients, and into the right jugular vein in 108 patients. A 30% solution of trisodium-citrate was used as a locking solution, and 2% mupirocin ointment was routinely applied to the exit site. The catheters were removed in 86 patients after 1-288 days, median 17.5 days. In 74 patients, there was either no need for further dialysis or an arteriovenous fistula was constructed (17 patients). In 10 patients, wire exchange was performed for correction of a displaced functional catheter (after 6-201 days), and in only two patients the catheters were removed due to infection on days 10 and 184. The longest period of a catheter functioning without intervention was 387 days. Fifteen patients died with functional catheters left in place (duration 1-387 days). In four patients, the catheters were still functional at the time of analysis (duration 198-268 days). Another nine patients were transferred to other dialysis centers (after they had been followed up at our center lasting for 1-63 days), with no data on their outcome after transfer. Fifteen patients were lost to follow up after insertion. Two single-lumen, noncuffed catheters in the same jugular vein, locked with 30% citrate, seem to be a safe and long lasting method of vascular access for hemodialysis and apheresis in some patients, but further prospective studies are needed to evaluate the clinical outcome of this type of vascular access.

Experience of 70-cm-long femoral tunnelled twin Tesio catheters for chronic haemodialysis

BACKGROUND

Tunnelled femoral catheters with their tip in the lower inferior vena cava (IVC) are proposed only in few cases, but they often provide less than optimal blood flows and frequently have complications. The aim of this prospective observational study is to evaluate the use of 70-cm-long tunnelled cuffed femoral twin Tesio catheters with their tip in the upper IVC for haemodialysis.

METHODS

Between May 2007 and May 2009, 25 tunnelled femoral catheters (fCVC) have been placed in 25 patients (77.7 +/- 10.8 years) with exhausted thoracic venous accesses or old patients with several comorbidities. Two 10 Fr carbothane 70-cm-long Tesio catheters with a Dacron cuff at 45 cm from the tip were placed in the femoral vein of each patient and then tunnelled; tips were in the upper third of the IVC. fCVCs were removed for either malfunction (Qb < 200 ml/min) or infection that did not resolve with antibiotics.

RESULTS

Technical success of placement was 100%. The 6- and 12-month assisted primary patency rate were respectively 67 +/- 13% and 54 +/- 17%. The mean session Kt/V was 1.45 +/- 0.19, and the blood flow was 270 +/- 17 ml/min. Six fCVCs have been removed: three for infection, one for accidental damaging and two for the making of a different vascular access. The main complications were 2 catheter tip thrombi, 3 tunnel infections and 11 fCVC-related bacteraemia (1.77 episodes per 1000 CVC-days).

CONCLUSION

The placement of twin fCVCs with their tip in the high IVC can provide an adequate dialysis and can be considered for patients with no remaining thoracic accesses.

Mechanical complications of long-term Tesio catheters

Vascular access catheters such as Tesio-Caths are preferentially inserted in the internal jugular vein and serve as access for hemodialysis. Complications related to the removal of these types of lines are uncommon. We report four patients in whom the tip of the Tesio-Cath broke and was left stuck in the superior vena cava. Although there is no defined limit to the maximum length of stay of vascular access catheters for dialysis, the possibility of catheter entrapment should be considered. It remains to be determined whether removing Tesio-Caths every 16- 18 months is beneficial in avoiding this complication.

Variability in reasons for hemodialysis catheter use by race, sex, and geography: findings from the ESRD Clinical Performance Measures Project

BACKGROUND

Race, sex, and geographic differences in hemodialysis vascular access use have been reported, but differences in reasons for catheter use have not been assessed.

STUDY DESIGN

Cross-sectional.

SETTING & PARTICIPANTS

Data obtained from the 2005 Centers for Medicare & Medicaid Services End-Stage Renal Disease Clinical Performance Measures Project for adult hemodialysis patients.

PREDICTORS

Race, sex, and geographic region.

OUTCOMES & MEASUREMENTS

Reasons for catheter use were categorized as short term and long term. Race, sex, and geographic associations with reasons were assessed by using bivariate analyses and multivariate logistic regression.

RESULTS

Of 8,479 hemodialysis patients, 3,302 (39%) used a fistula, 2,725 (32%) used a graft, and 2,299 (27%) used a catheter. We placed 857 patients with a catheter (37%) in the short-term-reason cohort and 1,404 (61%) in the long-term-reason cohort, and 38 (2%) lacked information to be placed. Reasons for catheter use were independently associated with race, sex, and geographic region. Whites were 43%, 49%, and 34% less likely than African Americans to use a catheter because of graft maturation, graft interruption, and all vascular access sites exhausted and 70% and 40% more likely because of fistula maturation and no fistula or graft surgically planned, respectively. Men were 50% less likely than women to use a catheter because of graft interruption and 80% more likely because of fistula maturation. Geographic end-stage renal disease network was associated with catheter use because of fistula maturation (P = 0.03), no fistula or graft surgically created (P < 0.001), and no fistula or graft surgically planned (P = 0.05).

LIMITATIONS

The cross-sectional study design precludes our ability to assess trends over time in reasons for catheter use. Associations were assessed for a limited set of variables.

CONCLUSION

Race, sex, and geographic differences in reasons for hemodialysis catheter use exist. Understanding these differences may aid in developing strategies to decrease catheter initiation rates.

Factors affecting long-term survival of tunnelled haemodialysis catheters--a prospective audit of 812 tunnelled catheters

BACKGROUND

In 2001, in the US, 23% of haemodialysis patients were dialysing through tunnelled venous catheters (TVCs), and in the UK (2006) there were 28% of prevalent patients using catheters. It is unlikely that numbers will significantly decrease. We present the results of a prospective audit of the survival of 812 TVCs placed in 492 patients at our institution over a 6-year period (comprising 212 048 patient catheter days or 7068 patient catheter months of follow-up). Four different designs of catheter were studied: Split-Cath III (Medcomp), HemoSplit (Bard), Tesio twin catheter (Medcomp) and Permcath (Quinton).

METHODS

We used Kaplan-Meier survival analysis with log-rank test, to compare the effect of different parameters on catheter survival. The relative importance of significant parameters was determined by Cox regression analysis.

RESULTS

We have shown a significant catheter survival advantage of first catheters over second and subsequent insertions, of right internal jugular site over left internal jugular and thereafter over femoral site, and of non-diabetic over diabetic patients. Patient age, sex and operator (physician in ward-based procedure room under ultrasound control or surgeon in operating theatre under fluoroscopic assistance) did not significantly affect survival. The Permcath design demonstrated inferior survival in all but first catheter insertions in catheter-naïve patients. The HemoSplit and Tesio twin catheter designs demonstrated best survival overall. By Cox proportional hazard modelling the design and the position of the TVC seemed to be the most significant independent survival factors.

CONCLUSIONS

Clinicians need accurate data regarding catheter survival, mode of insertion and design, to inform practice.

Fluid Mechanics and Clinical Success of Central Venous Catheters for Dialysis-Answers to Simple but Persisting Problems

Over 60% of patients initiating chronic hemodialysis in the United States have a chronic central venous catheter (CVC) as their first blood access device. Although it would be better if these patients started dialysis with fistulas, the CVC is used because it is a reliable and relatively safe method for obtaining blood access over a period of months. Drawing blood from a vein at 300-400 ml/minute is a relatively delicate and somewhat unpredictable process, and there is always a tendency for the vein wall to draw over the arterial tip and obstruct flow. Several methods have been employed to minimize this problem and maximize blood flow, and differing catheter designs have resulted. With all of the different catheter designs now on the market, it is natural to ask what is the logic of different designs. Moreover, in the absence of many direct comparative studies it is natural to ask whether one design is really better than another. There is some misinformation regarding catheter design and function. The following is a list of 10 frequently asked questions In this review, the hydraulic features of CVC are discussed and explained, and logical answers are provided for the following questions: 1. Why do ''D'' catheters flow better than concentric or side by side catheters? 2. Why are all catheters about the same diameter? Does making them bigger really decrease the resistance to flow? 3. Why might a split tip catheter flow better than a solid body catheter? 4. What happens to injections of lock solution at catheter volume? 5. What's better-numerous side holes or none? 6. Why does blood rise into some internal jugular catheters over time, displacing the lock solution? 7. How can a little kink (or stenosis) decrease flow so much? 8. Where should the tips be placed-superior vena cava or right atrium? 9. Which is really better, splitsheath or over-the-wire placement? 10. Which dialysis access has a lower complication rate--CVC or arteriovenous (AV) graft? There remain important problems with CVC for dialysis. With a few more improvements, chronic CVC for dialysis could become a painless, effective and safe long-term access for the majority of dialysis patients and acceptable as an alternative to AV grafts.