Catheter lock heparin concentration: effects on tissue plasminogen activator use in tunneled cuffed catheters

The optimal cost-effective heparin concentration for locking tunneled cuffed hemodialysis catheters (TCC) is unclear. We performed a retrospective review of tissue plasminogen activator (tpa) use in TCC in 2 hemodialysis units that used different heparin concentrations for TCC lock to evaluate the effectiveness of lower dose heparin as a lock for TCC. Catheter blood flow rate per treatment, units of heparin given during treatments, patient hemoglobin values and use of warfarin, and tpa use were compared for all patients using TCC for at least 3 months in 2 in-center hemodialysis units between 11/04 and 5/05. Both units used the same type of catheters and biocompatible, non-re-use dialyzers. Unit A used heparin 1000 U/mL for catheter locks, and Unit B used heparin 10,000 U/mL for catheter locks. Twelve of 19 Unit A patients, tpa and 14 of 45 Unit B patients received intracatheter during the study period (p=0.0009). There were no differences in the number of patients on warfarin, treatment blood flow rate, or mean hemoglobin levels between the 2 groups. The mean heparin units given during hemodialysis treatments was higher in Unit A patients (3.92+/-2.2 vs. 3.83+/-2.5 1000 U, p=0.05). Assuming a 4.1 mL total catheter lumen volume, the cost of heparin 1000 U/mL lock was 0.20 dollars per treatment and heparin 10,000 U/mL cost 2.67 dollars/treatment; tpa cost 89.02 dollars/use. Using the 10,000 U/mL heparin as a catheter lock was associated with less frequent use of tpa. However, the significantly lower cost of the 1000 U/mL heparin could result in significant savings despite higher tpa use. This retrospective, uncontrolled study of a small number of patients suggests that comparing low and high heparin concentrations as a TCC lock would be worthwhile. Prospective studies would be helpful to define the most appropriate and cost-effective lock for TCC.     

Ethanol combined with heparin as a locking solution for the prevention of catheter related blood stream infections in hemodialysis patients: A prospective randomized study

Introduction: Ethanol lock solution has been mainly administered in paediatric and home parenteral nutrition patients in order to prevent catheter related blood stream infections (CRBSI). Its utility in hemodialysis (HD) patients with non‐tunneled‐uncuffed catheter (NTC) has been poorly explored. Methods: We conducted a prospective randomized study in chronic HD patients requiring a newly inserted NTC‐while awaiting for the maturation of an already established arteriovenous fistula (AVF) or arteriovenous graft (AVG) or tunneled‐cuffed catheter insertion. Patients were randomized in two groups: Group A, where the lock solution was ethanol 70% + unfractionated heparin 2000 U/mL and group B, that received only unfractionated heparin 2000 U/mL. Primary end point was CRBSIs whereas exit site infections, thrombotic and bleeding episodes were the secondary end points. Findings: One hundred three HD patients were enrolled in the study (group A, n = 52; group B, n = 51). The median number of catheter days was 32 for group A (range: 23–39) and 34 (range: 27–40) for group B with no statistically significant difference between the two groups. Group A (ethanol + heparin) demonstrated 4/52 episodes (7.69%) of CRBSI whereas Group B (heparin) 11/51 episodes (21.57%) (P = 0.04). CRBSI rates per 1000 catheter days were 2.53/1000 catheter days for group A and 6.7/1000 catheter days for group B (P = 0.04). Mean cumulative infection‐free catheter survival in the ethanol group did not differ significantly compared to the heparin group (log‐rank test = 2.99, P = 0.08). Thrombotic episodes did not differ between the two groups. Discussion: Locking of NTCs in HD patients with ethanol 70% + unfractionated heparin reduces CRBSI rates without increasing the thrombotic episodes.     

The CLOCK trial,a double‐blinded randomized controlled trial: Trisodium citrate 30% and minocycline 3 mg/mL plus EDTA 30 mg/mL are effective and safe for catheter patency maintenance among CKD 5D patients on hemodialysis

Introduction: Poor blood flow rate (PF) is highly prevalent among CKD 5D patients with long‐term central venous catheters. Heparin catheter lock solutions are commonly used to maintain catheter patency, however the incidence of PF remains high. The purpose of the CLOCK Trial was to evaluate two catheter lock solutions on reduction of PF incidence. Methods: Seventy‐five CKD 5D patients on high‐efficiency hemodialysis at the Integrated Centre of Nephrology (Guarulhos, Brazil) were randomized 1:1:1 to receive a lock solution combining minocycline 3 mg/mL with the anticoagulant/chelation agent EDTA 30 mg/mL (M‐EDTA) or heparin 1000 IU/mL (H) or trisodium citrate 30% (TSC) vs. Hfor 15 weeks. A total of 68 patients completed the trial in which both investigators and patients were blinded to treatment allocation. The primary end‐point was the occurrence of hydraulic resistance and secondary safety end‐point was adverse drug reactions related to the lock solutions. Findings: At the beginning of the trial, 7 patients were excluded from this trial due to their poor catheter care. The incidence of hydraulic resistance was significantly higher among patients on H (18/23) compared to TSC (4/22) and M‐EDTA (2/23) lock solutions, (P < 0.001). Discussion: The CLOCK Trial suggests TSC and M‐EDTA may preserve catheter patency better than H. TSC may be a better option due the lack of association with long‐term antimicrobial resistance.     

Air-Bubble Method of Locking Central-Vein Catheters for Prevention of Hub Colonization: A Pilot Study

Background: The major source of catheter‐associated bacteremia is contamination of the catheter hub during connection–disconnection procedures. A new method of catheter locking has been developed wherein anticoagulant is injected first, followed by a 0.1‐mL air bubble and 0.9 mL of bactericidal solution. The anticoagulant is then located at the catheter tip and the bactericidal solution is located at the catheter hub. The air bubble prevents mixing of the two solutions. The bactericidal solution was acidified concentrated saline (ACS). The 27% saline solution has a pH of 2.0. ACS was chosen because it is theoretically harmless if injected in the amount used to lock the catheter lumens. The goals of this pilot study were to determine whether the new method of catheter locking is easy to perform with available syringes and whether eventual injection of the experimental solution is well tolerated. Methods: Ten patients were randomly assigned, either to heparin lock (5 patients, 62 treatments) or air‐bubble method (5 patients, 56 treatments). In the control group, the catheters were locked with heparin, 5000 U/mL. In the experimental group, the catheters were locked with heparin, air bubble, and ACS. Altogether, the lumens were overfilled by 0.2 mL. Results: Compared to the routine method, the experimental method required a 1‐ to 2‐min‐longer procedure time. There were no errors in proper sequence of injections into the lumina. There were no episodes of bacteremia related to hub contamination in either group. In the air‐bubble group, there was one case of bacteremia associated with purulent drainage from the exit and the same organism in both cultures. In three instances in each group, the locking solution could not be aspirated and was injected without any subjective symptoms or objective signs. Conclusion: We conclude that the air‐bubble method of locking central‐vein catheters is easy to perform. In three instances of air‐bubble and ACS injection, there were no adverse effects. A full‐scale prospective randomized study is feasible and warranted.     

Antibiotic lock: In vitro stability of gentamicin and sodium citrate stored in dialysis catheters at 37 °C

Catheter‐related bacteremia (CRB) is a major cause of morbidity and mortality especially among patients receiving hemodialysis. Antibiotic lock therapy represents a promising technique in the treatment of CRB. Several studies have evaluated antibiotics in combination with heparin as an interdialytic locking solution for prophylaxis of CRB. The objective of this study was to evaluate the stability of gentamicin and sodium citrate in hemodialysis catheters as an interdialytic lock. Solutions containing gentamicin 2.5 mg/mL and sodium citrate 40 mg/mL (4%) were prepared individually and in combination. The solutions were instilled into dialysis catheters and stored at 37 °C for 96 h. Samples were withdrawn randomly from catheter lumens at 24‐hour intervals for 4 days and stored at ?20 °C until analysis. The samples were analyzed with validated, stability‐indicating HPLC assays. The luminal concentration of gentamicin 2.5 mg/mL, sodium citrate 40 mg/mL (4%), and the combination was determined on study days 0, 1, 2, 3, and 4. When gentamicin was combined with sodium citrate and stored at 37 °C in dialysis catheters, the solution showed no decrease in either the gentamicin or the sodium citrate concentrations over the 96‐hour study period. The percent of the original concentration at 96 h was 102.4±1.03 for gentamicin and 102.9±1.25 for citrate (P=0.5556). The combination of gentamicin 2.5 mg/mL and sodium citrate 40 mg/mL (4%) can be retained in hemodialysis catheters for at least 96 h at 37 °C with no evidence of degradation.     

Concentrated Sodium Citrate (23%) for Catheter Lock

For chronic central venous dialysis catheters, the standard method for maintaining catheter patency between treatments is to instill (lock) catheters with 5000 – 10 000 units of heparin in each lumen. Sodium citrate (citrate) is an anticoagulant with intrinsic antibacterial activity (at 20% concentration or higher). Citrate has only transient anticoagulant effects if accidentally infused to the patient. Prior studies of citrate as a catheter lock solution have utilized citrate concentrations of 1% in combination with 27 mg/mL gentamicin. We changed clinical protocols for catheter locks using various solutions, including concentrated citrate, in a dialysis unit with 50% of patients having chronic central venous catheters [40 catheters total, mostly Ash Split Cath (Medcomp, Harleysville, PA, U.S.A.) but some Tesio (Medcomp) and Hickman (BARD, Salt Lake City, UT, U.S.A.) catheters]. At 3‐ to 4‐month intervals, the standard catheter lock solution for the unit was varied on the following schedule: heparin; 10% citrate with 3 mg/mL gentamicin; 20% citrate with 3 mg/mL gentamicin; heparin; and 23% citrate. Catheters were not routinely removed during treatment of bacteremia. Incidence of bacteremia in patients with catheters using heparin as catheter lock was 4.32 episodes per 3000 patient‐days (equivalent to percent of patients with catheters having bacteremia per month). The incidence of bacteremia decreased to 1.68 using 20% citrate/gentamicin as catheter lock (p < 0.05) and to 0% with 47% citrate (p < 0.05). Incidence of bacteremia increased on return to heparin and decreased again with use of 23% citrate to 1.79 (p < 0.05). Use of urokinase for occluded catheters also significantly decreased with citrate during the time that it was available (p = 0.02). Life table analysis indicated an 83% survival of Ash Split Cath catheters at 1 year, in this unit. Concentrated citrate is an effective catheter lock solution that may provide prolonged central venous catheter use with a diminution in catheter‐related infections and occlusion.     

Efficacy of Tissue Plasminogen Activator for Thrombolysis in Central Venous Dialysis Catheters

Background:  Low blood flow is a frequent complication of central‐vein (CV) dialysis catheters. Since thrombotic occlusion accounts for many cases of reduced blood flow, it is common practice to administer empiric thrombolytic therapy in an attempt to restore catheter patency and improve function.
Methods:  We prepared tissue plasminogen activator (tPA) from 50 mg lyophilized powder, which was diluted (1 mg/mL) in sterile water for injection. A volume of 1 mL was frozen in 3 cc polystyrene syringes at −20 °C and thawed at room temperature when needed. tPA was then administered into the arterial and venous ports of the central venous catheter in a volume equal to the manufacturer's stated luminal volume and was allowed to dwell for 30 minutes.
Results:  tPA was administered 62 times in 25 patients with 30 catheters (11 Tesio, 17 PermCath, 2 Shiley) for treatment of low blood flow (pump speed < 250 mL/min). Complete restoration of patency was achieved in 23 episodes (mean blood flow pre‐tPA 130 mL/min; post‐tPA 320 mL/min); partial restoration of patency was achieved in 20 episodes (mean blood flow pre‐tPA 69 mL/min; post‐tPA 233 mL/min). tPA was just as likely to be effective in patients with complete catheter occlusion (i.e., no blood flow) as it was when some initial blood flow was present. Nineteen episodes failed to respond to tPA. These episodes occurred in 13 catheters, 12 of which ultimately underwent radiologic evaluation; an extraluminal cause for low blood flow was found in all 12 catheters (6 malpositioned, 6 fibrin sheaths).
Conclusions:  tPA at a dose of 1 mg/mL is effective for restoring patency in CV dialysis catheters. Failure to respond to tPA strongly suggests an extraluminal cause of catheter malfunction.     

Heparin‐induced thrombocytopenia due to heparin lock in a hemodialysis patient: A case report

Heparin‐induced thrombocytopenia (HIT) is a potentially fatal clinical condition which can develop after exposure to unfractionated or low‐molecular‐weight heparins. Even small doses of heparin such as heparin flushes in hemodialysis catheter can induce the development of HIT. However, the true incidence of heparin lock‐related HIT is unknown. We report a 58‐year‐old woman with acute kidney injury because of obstructive uropathy who developed HIT after heparin‐free hemodialysis. She was found to have severe thrombocytopenia with deep vein thrombosis of left lower limb and arterial thrombosis of the right anterior and middle cerebral arteries. The heparin‐platelet factor 4 antibody was positive and she was put on plasmapharesis. However, her condition further deteriorated and succumbed shortly. Heparin lock solution in the hemodialysis catheter was believed to be the cause of HIT in our patient.     

Prevention and Treatment of Thrombosis Associated With Long-Term Hemodialysis Catheters

Soft, cuffed, central vein hemodialysis catheters are used in about 20% of chronic hemodialysis patients in the United States, because long-term arteriovenous blood access cannot be maintained in an aging patient population with a large proportion of diabetics. The most frequent complication of these catheters is thrombosis. The treatment of catheter-related thrombosis is difficult and expensive; thus the emphasis should be on prevention. The preferred material for a long-term catheter is silicone rubber, since it is the least thombogenic. Anticoagulation should be more vigorous during “catheter dialysis” than during “fistula dialysis.” Heparin is the least expensive and most convenient anticoagulant, suitable for over 99% of chronic dialysis patients. The dose of heparin for sufficient anticoagulation depends on many factors, varies widely, and should be established for each patient based on activated clotting time (ACT). ACT should be kept over 270 sec throughout dialysis. Recently we introduced a method of locking catheter lumina with a predetermined amount of heparin; this heparin is not discarded before the next dialysis, but serves as a loading dose. This saves a number of connections/ disconnections and decreases dialysis-associated blood losses. To prevent catheter thrombosis, over 60% of patients require warfarin in sufficient doses to keep the international normalized ratio (INR) between 1.5 and 2.5. The most common catheter-related thrombus is a periluminal fibrin sleeve. Locking the catheter with urokinase to dissolve the clot is of little value, because the bulk of the thrombus is outside the catheter. We have found a high-dose (250 000 U or more) intradialytic urokinase infusion through the venous chamber to be a very efficient and convenient method for dissolving clots. Cumulative success of up to three infusions is over 99%. This obviates the need of catheter stripping or replacement, which is more cumbersome and expensive.     

Initial clinical experience with a new heparin-coated chronic hemodialysis catheter

In this paper we wish to report our clinical experience with a new heparin-coated dialysis catheter with a symmetric tip. Over a 16-month period, 60 heparin-coated Tal Palindrome^™ catheters were placed in 57 patients. Catheter patency, catheter-related complications, and reasons for catheter removal were recorded. The patient's initial cause of end-stage renal disease, underlying diseases, and site of access were recorded as well. Patients were specifically followed for development of heparin-induced thrombocytopenia. Patient ages were 34–91 (average 66). Fifty-four percent of patients had a history of diabetes. Sixty catheters were placed for a total of 5353 catheter-days. The average catheter indwell time was 107 days (range of 2–381 days). Catheter-related infection occurred in 6 patients over the study period, with a rate of 1.12/1000 catheter-days. Bacteremia occurred in 3 patients with a rate of 0.56/1000 catheter-days. Six catheters were removed or exchanged due to malfunction. There was no incidence of heparin-induced thrombocytopenia. Initial clinical experience with the heparin-coated Tal Palindrome^™ hemodialysis catheter demonstrated safe, reliable use, and low infection rates.     

Comparison of alteplase (tissue plasminogen activator) high‐dose vs. low‐dose protocol in restoring hemodialysis catheter function: The ALTE‐DOSE study

Hemodialysis catheter (HDC) dysfunction due to thrombosis is common, and dysfunction incidence can reach up to 50% within 1 year of use. Although administration of intraluminal alteplase (tissue plasminogen activator [tPA]) is the standard of practice to pharmacologically restore HDC function, there are no evidence‐based guidelines concerning the optimal tPA dose. The purpose of this study was to compare the efficacy of 1.0‐mg vs. 2.0‐mg tPA dwell protocols in restoring the HDC function in thrombotic dysfunctional catheters. A retrospective, single‐center study was conducted on two independent cohorts of patients; the first (n = 129) received 2.0 mg tPA/catheter lumen, while the second (n = 108) received 1.0 mg tPA/catheter lumen. Kaplan–Meier and Cox regression analyses were performed to compare the catheter survival time between patients who received 1.0 mg tPA and those who received 2.0 mg tPA. Catheter removal occurred in 25 (19.4%) of those catheters treated with 1.0 mg tPA compared with 11 (10.2%) of catheters treated with 2.0 mg tPA (P = 0.05). The hazard ratio (HR) for catheter removal was 2.75 (95% confidence interval [^95%CI] = 1.25–6.04) for the 1.0‐mg tPA cohort compared with the 2.0‐mg tPA cohort. Correction added on 3 December 2012, after first online publication: The tPA cohort values were changed. Female gender (HR = 2.51; ^95%CI = 1.20–5.27) and age (HR = 0.96; ^95%CI = 0.94–0.98) were also associated with catheter survival. Our findings suggest that treatment of dysfunctional HDC with 2.0‐mg tPA dwells is superior to 1.0‐mg tPA dwells.     

Catheter‐related bacteremia and mortality in frequent nocturnal home hemodialysis

Frequent nightly home hemodialysis (NHHD) has emerged as an attractive alternative to thrice weekly in‐center hemodialysis, albeit with preponderant long‐term hemodialysis catheter used. Sixty‐three NHHD patients from University of Virginia Lynchburg Dialysis Facility were matched 1:2 with 121 conventional hemodialysis patients admitted to Fresenius Medical Care North America facilities from January 1, 2007 to December 31, 2010. Matching considered age (± 5 years), gender, race, dialysis vintage, and diabetes. The primary end‐point was the combined incidence of bacteremia/sepsis, for up to 20 months or upon changing to a fistula/graft (with catheter removal), transferring to peritoneal dialysis (PD), or at the time of kidney transplant or death. No significant differences were observed in rate of fistula/graft conversion, transfer to PD, transplant, or death between NHHD and in‐center hemodialysis (IHD) groups. For the first catheter used, the rate of catheter‐related sepsis was not significantly different between the NHHD (1.77 per 100 patient months) and IHD (2.03 per 100 patient months; P = 0.21). Combining all catheters, the rate of bacteremia/sepsis per 100 patient months in the NHHD group was 1.51 and in the IHD group was 2.01 (P = 0.35). Median catheter lifespan for the first catheter was 5.6 (1.7～19.0) for NHHD and 4.6 (2.7～7.8) for the IHD group (P = 0.64), and for all catheters used was 5.2 (Q1～Q3 = 1.5～15.2) months in NHHD group, and 4.1 (2.0～6.8) months in IHD group (P = 0.20). The rate of bacteremia and death is not different for up to 20 months in catheter users who dialyze via frequent NHHD vs. thrice weekly IHD.     

Antibiotic lock solutions allow less systemic antibiotic exposure and less catheter malfunction without adversely affecting antimicrobial resistance patterns

There are current concerns that antibiotic lock solutions (ABL) can induce antimicrobial resistance in long‐term hemodialysis patients. Retrospective chart review of 157 children on hemodialysis between January 1997 and June 2006 was performed. In ERA I, only systemic antibiotics were used. In ERA II, ABL were added to systemic antibiotics when needed. In ERA III, ABL were used for treatment of all cases of catheter‐related bacteremia (CRB) and for CRB prophylaxis in high‐risk patients. The study includes 111,325 catheter days. The CRB incidence was 3.9 CRB/1000 catheter days. There was significant decrease for the total systemic antibiotic exposure (P = 0.0484) and the percentage of catheters lost to malfunction (P = 0.001) in ERA III. Protocol ABL exposure was associated with a trend to increased tobramycin‐gentamicin resistance for gram‐positive CRBs (P = 0.2586) but with improved tobramycin‐gentamicin resistance for gram‐negative (P = 0.0949) and polymicrobial CRBs (P = 0.1776) and improved vancomycin resistance for gram‐positive CRBs (P = 0.0985). This retrospective analysis does not support the premise that ABL use will promote antimicrobial resistance in the hemodialysis population. The decreased exposure to systemic antibiotics by vigorous ABL use may even improve the antimicrobial resistance patterns in this population in the long term.     

Inserting tunnelled hemodialysis catheters using elective guidewire exchange from nontunnelled catheters: Is there a greater risk of infection when compared with new‐site replacement?

The objective is to evaluate bacteremia outcomes and survival rates when using guidewire exchange to place tunnelled hemodialysis catheter (THDC) compared with a new-site replacement. Retrospectively, all patients were identified who received a THDC between January 1, 2000 and January 1, 2007. Any THDC having received antibiotic line locks or tunnel-to-tunnel exchange were excluded. This left 408 THDC placed in 329 patients: 46 guidewire exchange, 362 new-site replacement. Bacteremia rate from the new-site insertion group was 3.0 per 1000 catheter days, the guidewire exchange group demonstrated a rate of 2.8 per 1000 catheter days. Local infection rates did not differ between the groups at 1.2 per 1000 catheters days. The actuarial catheter survival rates using Kaplan-Meier survival analysis demonstrated no difference between the 2 groups. The placing of tunnelled cuffed hemodialysis catheters to replace temporary catheters using a guidewire exchange did not contribute to further episodes of sepsis and has the advantage of preserving venous access and minimizing invasive procedures for the patient.     

Alteplase vs. urokinase for occluded hemodialysis catheter: A randomized trial

Introduction Thrombosis of tunneled central venous catheters (CVC) in hemodialysis (HD) patients is common and it can lead to the elimination of vascular sites. To compare the efficacy of alteplase vs. urokinase in reestablishing adequate blood flow through completely occluded vascular catheters. Methods In this randomized study, patients with completely occluded tunneled HD catheters received 40 minutes intracatheter dwell with alteplase (1 mg/mL) or urokinase (5000 IU/mL). Primary endpoint was the proportion of patients with occluded catheters achieving post‐thrombolytic blood flow of ≥250 mL/min. Safety endpoints included the incidence of hemorrhagic and infectious complications. Findings Eligible adult patients (n = 100) were treated with alteplase (n = 44) or urokinase (n = 56). The two groups were similar in gender (male: 51.8% vs. 56.8%, P = 0.35), age (60 ± 12 vs. 59 ± 13 years, P = 0.71), time on dialysis (678 ± 203 vs. 548 ± 189 days, P = 0.77), diabetes and cardiovascular disease (55.6% vs. 70.4%, P = 0.08 and 17.8% vs. 22.7%, P = 0.38, respectively), jugular vein as main vascular access (54.8% vs. 62.5%, P = 0.57), and time of CVC (278 ± 63 vs. 218 ± 59 days, P = 0.67). Primary success with alteplase and urokinase occurred in 42/44 (95%) vs. 46/56 (82%), P = 0.06. Success was not achieved after the second dose of alteplase and urokinase in 1 and 7 cases, respectively (2% vs. 12%, P = 0.075). Serious adverse effects were not observed in both groups. There was no difference between the two groups in infectious complications (P = 0.94). Discussion Alteplase and urokinase are effective thrombolytic agents for restoring HD catheter patency. Our study has revealed a likely slight superiority of alteplase over urokinase for unblocking central lines, but which has enrolled too few patients to be able to detect a difference of this size.     

Heparin leak from a hemodialysis catheter causing major bleeding,ultimately leading to transplant rejection and death

Leakage of hemodialysis catheter‐locking solutions into the circulation has been reported in in vitro and in vivo studies, although there have been few reports of serious clinical adverse events. We describe a case of heparin leak from a hemodialysis catheter, which caused significant clinical bleeding requiring multiple transfusions and may have ultimately been responsible for the patient's death after transplantation.     

An unusual case of an irretrievable hemodialysis catheter in a patient with end stage renal disease

Hemodialysis catheters are associated with higher risks of complications compared to arteriovenous fistulas and grafts. Some common complications of dialysis catheters include infection, thrombus formation, central venous stenosis, and mechanical dysfunction. Rarely, catheters can become firmly adhered to a vessel wall. Catheter adhesion is a serious complication that can impact the delivery of safe and effective dialysis to affected patients. Adherent catheters commonly present insidiously with no overt diagnostic signs and symptoms or antecedent catheter malfunction. Prognosis is variable, but can be potentially fatal depending on the severity of adhesion, and sequelae of complications. There are no standardized methods of therapy and treatment strategies are anecdotally reported by interventional radiology, vascular, and cardiothoracic surgery. We hereby describe a case of hemodialysis catheter that has become firmly embedded within the superior vena cava wall. We review the available literature on the epidemiology, risk factors, long‐term sequelae, and known management strategies of adherent catheters. The development of preventative measures will be of great importance given serious complications and limited treatment options. Clinical awareness and understanding of this rare condition is imperative to the prevention and management of adherent catheters.     

Efficacy of preventing hemodialysis catheter infections with citrate lock

Prevalent use of tunneled dialysis catheters can reach 30%. Infection remains the most serious catheter‐related problem. Catheter locks are increasingly used for prevention, but are not yet recommended either by the Food and Drug Association or European Medicines Agency, on the basis of increasing bacterial resistance or lock toxicity. The aim was to test safety and effectiveness of citrate. A prospective, interventional study was conducted to assess the safety and efficacy of a 30% citrate lock in preventing catheter‐related bacteremia (CRB). A total of 157 prevalent tunneled catheters were locked with citrate and prospectively followed during a 1‐year period. The primary endpoint was first CRB diagnosed according to two of the diagnostic criteria for Catheter Infection of Centers for Disease Control and Prevention (CDC), namely definite and probable infection. The CDC criterion of possible but not proved infection was not considered. This citrate lock cohort (n = 157) had 10 episodes of CRB. We observed 0.49 CRB episodes/1000 patient‐days and the mean infection‐free catheter day was 130.6 ± 100.9. No clinically relevant adverse events were observed. No proved tunnel or exit site infection was observed and no patients died because of CRB. Catheter obstruction episodes were reported on 69 occasions out of 14 catheters. These results were compared with an historical cohort from a previous study of catheter locking with low‐dose gentamicin and did not show significant difference in efficacy. Citrate lock is effective in preventing CRB. No toxicity was observed. The use of citrate lock may have advantages over antibiotic locks: No reported bacterial resistance, lower industrial cost, and less manipulation.     

Central Venous Catheters for Hemodialysis: How to Overcome the Problems

The use of central venous dialysis catheters is increasing in clinical practice. These devices, although relatively easy to insert, do have problems. Catheter size limits the amount of dialysis that can be delivered. Central venous hemodialysis catheters minimize cardiopulmonary recirculation, but have increased potential for access recirculation compared to native or artificial arteriovenous (AV) fistulas and grafts. Developments in catheter design and optimal positioning have improved the amount of dialysis that can be delivered. Similarly, infection rates are improving with careful attention to peri‐insertion care and the use of topical antiseptics and antibiotics. Although catheter thrombus remains a problem, the introduction of recombinant tissue plasminogen activator and mechanical dislodgement with an endoluminal brush have improved patency rates, but some patients may require long‐term warfarin therapy.