Thrombotic complications of indwelling central catheters used for chronic hemodialysis

Streptokinase Therapy for Occluded Tenckhoff Catheters in Children on CAPO

Streptokinase was infused through the partially thrombosed Tenckhoff catheters of four children on continuous ambulatory peritoneal dialysis (CAPD). Radiographic contrast studies performed before and after the infusions demonstrated dramatic dissolution of the fibrin thrombi associated with restoration of normal catheter function. The catheters subsequently functioned for an average of 12.5 months. No allergic or hemorrhagic complications were noted in association with the infusions. Coagulation studies revealed no evidence for systemic streptokinase absorption. We suggest that streptokinase, when given in the manner described, is a safe and effective treatment of thrombosed Tenckhoff catheters in children.

Central Venous Catheter and the Hemodialysis Patient: A Difficult Symbiosis

In the last ten years, tunneled central venous catheters (pCVCs) have been increasingly utilized in chronic hemodialysis patients, sometimes in the place of fistulas. They have gained popularity for their unquestioned advantages, such as the possibility for immediate use. However, several problems have emerged following their diffusion. In this paper we review the main complications of pCVCs. Complications connected with insertion are generally due to an inaccurate approach to the vein. Ultrasonographic guidance has partially solved this problem and EC-ECG (endocavitary ECG) allows an accurate positioning of the tip. Infections, venous and/or pCVCs) thrombosis and dysfunctions are the most important catheter-related complications. Infections may occur with and without symptoms of systemic illness. Early diagnosis and appropriate antibiotic treatment are essential for saving the catheter. The pathogenesis of infections and strategies for prevention are discussed. Thrombosis and stenosis are well known complications of subclavian and jugular catheterization. In uremic patients, for temporary use, we suggest using the femoral position. Protocols for application of thrombolytic agents in pCVCs are considered. Dysfunction, defined as the failure to maintain a blood flow of at least 250 ml/min, remains the Achilles’ heel of the system. Adequate look therapy and tip position are only two basic aspects. In conclusion, a pessimistic outlook on the matter could lead us to consider that the advantages of catheter use are far outweighed by the disadvantages. However, we cannot avoid using central venous catheters in our dialysis units and a great challenge awaits both physicians and manufactures in the coming years.

The Natural History of Tunneled Hemodialysis Catheters Removed or Exchanged: A Single-Institution Experience

PURPOSE

To track the natural history of tunneled hemodialysis catheters requiring removal or exchange at a single institution.

MATERIALS AND METHODS

Over a 2-year period, tunneled hemodialysis catheters that presented to interventional radiology for removal or exchange were entered into this retrospective study. Patient demographics, catheter location, dwell time, and indication for removal were recorded. Pull-back contrast venography was performed with imaging over the chest. Catheters were then removed or exchanged.

RESULTS

Three hundred thirty-four tunneled dialysis catheters were removed or exchanged in 207 patients; 108 male, median age 53 years. Dwell time, available from 296 catheters, ranged from 1 to 114 days (median, 66 days) for a total of 32,847 catheter days. One hundred three catheters were removed for infection, yielding a rate of infection requiring catheter removal of 3.0 per 1,000 catheter days. One hundred catheters were removed for other working access, and 96 catheters were exchanged for poor function. Two hundred sixty-five were removed or exchanged from the internal jugular vein, 22 from the subclavian vein, and 24 from the femoral vein. One hundred seventy-two (76%) of the 226 catheters studied with contrast had fibrin sheaths; of which 42 had thrombus identified along the catheter tract. One hundred ninety-three catheters were removed, and 141 catheters were exchanged for new catheters with 82 catheters receiving balloon disruption of the fibrin sheath.

CONCLUSIONS

Approximately one third of tunneled dialysis catheters are removed for infection, one third for other working access, and one third for poor function. Catheters usually remain in the patient for a median of 2 months. Fibrin sheaths associated with hemodialysis catheters are very common. Thrombus formation around the sheath is frequent.

Multiple myeloma and hypercoagulability leading to internal jugular vein thrombosis in a dialysis patient

A 68-year-old male patient with end-stage renal failure on maintenance hemodialysis using a right internal jugular dual-lumen catheter developed thrombosis of the internal jugular vein with extension into the superior vena cava after removal of the catheter. As he developed a lower backache with MRI finding of disease of the D11 and D12 vertebrae, a bone biopsy performed showed multiple myeloma. Anticoagulant therapy led to recanalization of the thrombosed veins.

Central venous catheter outcomes in nocturnal hemodialysis

Central venous catheter (CVC) as hemodialysis (HD) access is associated with great morbidity and mortality in the end-stage renal disease population. Quotidian, nocturnal HD (NHD) is a novel dialysis modality associated with cardiovascular and quality of life benefits, yet there is a concern of a potential increase in vascular access-related complications through patient-directed access cannulation. We aimed to determine catheter incidence and prevalence in the NHD population and to compare rates of catheter-related: infection, thrombolytic administration, hospitalization, survival, and reasons for their loss before and after conversion to NHD. This observational cohort consisted of incident and prevalent NHD patients between 1 November 1993 and 31 May 2005. Rate comparisons were determined by Poisson analysis and catheter survival by Kaplan-Meier curves. Eighty-one CVCs in 33 patients accounted for 17 150 CVC days (CVCD); 40 CVCs were exclusively used for conventional three times weekly HD (CHD) and 25 CVCs were exclusively used during NHD. The incidence and prevalence of CVC use in our NHD population was 35 and 25%, respectively. Comparing CHD to NHD, no significant differences were seen in total rates of infection, thrombolytic administration, or access-related hospitalization. Catheter survival was superior in NHD vs CHD (P=0.03). Adverse terminal catheter events were higher during CHD than NHD (5.84 vs 2.92/1000 CVCD; P=0.03). CVC use and complications in NHD is comparable to that in CHD with the benefit of longer cumulative survival. More frequent CVC use should not be a deterrent to NHD.

Clinical Course Associated with Vascular Access Type in a National Cohort of Adolescents Who Receive Hemodialysis: Findings from the Clinical Performance Measures and US Renal Data System Projects

Limited research has described clinical outcomes that are associated with the type of vascular access in pediatric patients who receive maintenance hemodialysis. This retrospective cohort study examined prevalent pediatric patients who were aged 12 to <18 yr and identified in the 2000 ESRD Clinical Performance Measures Project as receiving in-center hemodialysis. Vascular access type as of December 31, 1999, was identified. These patients were linked with 1 yr of data (January 1, 2000, through December 31, 2000) from US Renal Data System standard analytic files that allow for the comparison of rates of hospitalizations and access complications by access type. Of the 418 patients who met inclusion criteria, the mean age was 15.6 yr, 53% were male, 49% were white, the mean time on dialysis was 22 mo, and 42% had a structural/urologic cause of ESRD; 42% of patients had an arteriovenous graft or fistula, and 58% had a vascular catheter. Patients with a vascular catheter as compared with those with a graft or fistula had the following adjusted relative risks (95% confidence interval): 1.84 (1.38 to 2.44) for hospitalization for any cause, 4.74 (2.02 to 11.14) for hospitalization as a result of infection, and 2.72 (2.00 to 3.69) for a complication of vascular access. Vascular catheters are the predominant access type in adolescent patients who receive maintenance hemodialysis and are associated with significantly more hospitalizations and complications.

Covalently grafted phospholipid monolayer on silicone catheter surface for reduction in platelet adhesion

We report a novel method of surface grafting a polymeric phospholipid system containing an acryloyl end group (1stearoyl-2-[12-(acryloyloxy)-dodecanoyl]-sn-glycero-3-phosphocholine) onto medical grade silicone catheters. The surface of silicone catheters was functionalized in a sequence of steps: plasma polymerization of allyl alcohol on the catheter surface, grafting acryloyl moieties and in situ polymerization of the pre-assembled acryloyl terminated phospholipids on the acryloyl functionalized catheter surface. The surface morphological changes analyzed by scanning electron microscopy (SEM) and atomic force microscopy (AFM), a sharp decrease in water contact angle, and appearance of N1s peak in XPS analysis indicated a successful monolayer grafting of the phospholipid. In platelet adhesion tests performed using platelets isolated from rabbit plasma, the phospholipid grafted surface showed fewer adhered platelets, without emerging pseudopodes or aggregation. However, ungrafted catheter surface showed large number of platelets in extensively spread and aggregated states. Thus, this modified phospholipid system and its simple grafting technique was very effective with regard to suppressing in vitro platelet adhesion on the silicon catheter surface.

Live Three-Dimensional Transthoracic Echocardiographic Assessment of Thrombus in the Innominate Veins and Superior Vena Cava Utilizing Right Parasternal and Supraclavicular Approaches

We report the usefulness of right parasternal and supraclavicular live three-dimensional transthoracic echocardiography in the delineation and follow-up of a thrombus involving a catheter placed in superior vena cava for dialysis in an adult patient with chronic renal disease.

Natural saline-flush is sufficient to maintain patency of immobilized-urokinase double-lumen catheter used to provide temporary blood access for hemodialysis

BACKGROUND

Thrombotic occlusion is a frequent complication of central venous catheters used to provide temporary blood access on hemodialysis therapy. Heparin-lock is conventionally used to maintain patency of the catheter, but the necessity of heparin-lock has not been determined yet.

METHODS

After the immobilized-urokinase double-lumen central venous catheter was inserted into 48 Japanese hemodialysis patients, 22 patients randomized to the heparin group received a 20-ml saline-flush, followed by 2 ml of 1,000 U/ml heparin-lock, and 26 patients randomized to the saline group received only the 20-ml saline-flush once a day for each lumen.

RESULTS

Thrombotic occlusion was observed in only 1 out of 22 patients in the heparin group and 1 out of 26 patients in the saline group. No significant difference of the catheter survival was observed between the two groups (p = 0.8599).

CONCLUSIONS

Natural saline-flush is sufficient for maintaining the patency of an immobilized-urokinase double-lumen central venous catheter.

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.

Central venous dialysis catheter dysfunction

Central venous catheter dysfunction is a limiting factor in regard to renal replacement therapy efficiency and can thus influence patient morbidity. Early catheter dysfunction is frequently due to mechanical problems such as inadequate positioning, kinking, or constriction, but early fibrin deposition can develop soon after insertion. Delayed dysfunction usually results from thrombus formation, either within the lumen, around the catheter ("fibrin sleeve"), or in the host vein. Catheter dysfunction is suspected clinically or documented by simple imaging studies. It is usually evident and manifested by failure to aspirate blood from the lumen(s), inadequate blood flow and/or high resistance pressures during hemodialysis. However, a more subtle dysfunction may lead to a high recirculation of dialyzed blood and be overlooked if dialysis adequacy is not monitored regularly. Local instillation of a fibrinolytic agent is usually successful in restoring catheter patency. Central venous dialysis catheters present intrinsic limitations consequent to their composition and design, whereas extrinsic limitations result from site of insertion, blood properties and anatomic particularities of a given individual. These characteristics largely determine overall catheter performances. Performance parameters to consider include maximal consistently achievable blood flow rate, resistance to blood flow indicated by arterial and venous pressures during hemodialysis, and blood recirculation rate. Catheter longevity is an important consideration for cuffed catheters implanted for long-term use. The tolerated blood recirculation within central venous dialysis catheters should be below 10% to 15%, and is ideally between 3% to 7% in most clinical settings. Several recent studies confirm that short femoral catheters recirculate significantly more than is desirable. Well functioning and nonreversed internal jugular and subclavian venous catheters have, in general, recirculation rates less than 5%. With regard to various performance criteria, the TwinCath (Medcomp, Harleysville, PA) appears particularly advantageous. In any case, a good catheter maintenance program is of critical importance for the prevention and the early detection of catheter dysfunction.

Silastic cuffed catheters for hemodialysis vascular access: thrombolytic and mechanical correction of malfunction

Silastic cuffed catheters are assuming a greater role in providing long-term vascular access for hemodialysis patients. However, catheter thrombosis, fibrin sheath formation, and catheter malposition are recurrent problems that reduce extracorporeal flow rates and shorten catheter life. We reviewed 163 consecutive episodes of catheter malfunction that occurred in 121 catheters in 88 patients over a 3.5-year period. Intraluminal instillation of urokinase was successful in reestablishing an extracorporeal flow rate of > or = 300 mL/min in 74% of episodes. The 42 remaining episodes (26%) were radiologically evaluated. Two catheters required replacement for catheter kinking or insufficient catheter length. Two additional catheters were malpositioned; both were successfully repositioned with percutaneous techniques. A fibrin sheath was detected encasing the catheter in 38 instances. The fibrin sheath was successfully stripped from the distal portion of the catheter in 36 of the 38 instances. Using endoluminal thrombolytic therapy and percutaneous mechanical techniques, we have extended the mean survival for catheters intended for permanent vascular access to 12.7 months and have allowed 95% of the catheters inserted for temporary use to reach their use goal. Tunnel tract infection and catheter-mediated bacteremia were the primary reasons for catheter removal.

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

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

Transhepatic PermCath for hemodialysis

The establishment and maintenance of a reliable vascular access continues to be a problem in hemodialysis. We report a patient with end-stage lupus nephritis who had no alternative for vascular access and failed peritoneal dialysis. A vascular access device (PermCath, Quinton Instrument Co, Bothell, WA) was inserted using a transhepatic approach. There were no bleeding or thrombotic complications. The catheter was replaced once through the same track due to poor blood flow and reinserted once after 5 days due to infection. The patient has been doing well and receiving adequate dialytic therapy for over 1 year with this form of vascular access.

Acute vascular access: new advances

Dual lumen central venous hemodialysis catheters have become the preferred form of acute of acute vascular access. Although they provide rapid angioaccess, these catheters are associated with a number of serious insertion complications. Furthermore, prolonged use can lead to late complications including infection and central venous stenosis. Recent advances in catheter construction as well as new techniques for line placement should reduce the incidence and severity of catheter-related problems.

The potential risk for subclavian vein occlusion in patients on haemodialysis

Subclavian vein (SCV) stenosis or occlusion can be a late complication of temporary haemodialysis or following catheterisation for intravenous hyperalimentation. In five patients with prior catheterisation or trauma of the SCV, incapacitating oedema of the upper extremity developed only after the creation of ipsilateral arteriovenous (AV) fistulas for haemodialysis. The duration of the previous catheterisation was 2 to 4 weeks. Massive upper extremity oedema developed at 10 days to 22 months with an average of 11 months after the establishment of AV fistulas. Subclavian-axillary vein bypass using a ringed polytetrafluoroethylene graft was successful for one patient and ligation of the AV fistulae led to good results for the other three. In planning vascular access procedures in the upper extremity, venography should be mandatory to try to prevent such complications if a previous history of subclavian catheterisation exits.

Staphylococcus aureus bacteremia in patients with Hickman catheters

PURPOSE

Determination of outcome and prognostic variables associated with Staphylococcus aureus bacteremia in patients with Hickman catheters.

PATIENTS AND METHODS

At the University of Washington Medical Center, 37 patients with Hickman catheters and S. aureus bacteremia were studied by retrospective chart review. Clinical features associated with each episode of infection were determined, and the relationships among clinical features, therapy, and outcomes were explored.

RESULTS

Only 18% of all Hickman catheter-associated S. aureus bacteremias and only 10% of those cases with exit site infections were cured without catheter removal. In seven of 41 episodes (17%), death or bacteremic relapse occurred. The best prognosis was found in infections with a low blood culture colony count (less than 1 colony/mL).

CONCLUSION

Hickman catheter-associated bacteremia due to S. aureus has a worse prognosis than other Hickman catheter-associated bacteremias. Early catheter removal should be considered except in cases with a remote, noncatheter focus of infection or in infections with no catheter-related physical signs and blood culture colony counts of less than 1/mL.

Use of a silicone catheter with a Dacron cuff for dialysis short-term vascular access

Polyurethane and Teflon subclavian vein catheters have been widely used for temporary vascular access for hemodialysis, but their use has been associated with a significant complication rate. A silicone dual-lumen catheter with a Dacron cuff placed in the internal jugular or subclavian vein was evaluated as a means of obtaining short-term vascular access. Sixty-two catheters in 54 patients provided a cumulative experience of 206 patient-months. Blood flow rates greater than or equal to 200 mL/min were achieved, with a mean recirculation of 2.1%. Catheter function was better with placement on the right side. Exit-site infections developed in nine patients, for a rate of 5.3 episodes per 100 patient-months; all resolved with antibiotics. Catheter-related bacteremia occurred in one patient, for a rate of 0.49 episodes per 100 patient-months, a rate much lower than rates reported for polyurethane and Teflon catheters. Clotting occurred in 24.5% of catheters, and thrombolytic therapy was always successful in restoring function. Because of the lower rate of complications, the silicone dual-lumen catheter with a Dacron cuff provides a safer alternative for short-term hemodialysis vascular access than the Teflon and polyurethane catheters.