Anticoagulation without catheter removal in children with catheter-related central vein thrombosis

Anticoagulation results in increased line salvage for children with intestinal failure and central venous thrombosis

PURPOSE

The purpose of this study was to investigate whether anticoagulation (AC) results in thrombus resolution and increased line longevity in children with intestinal failure (IF) and catheter-associated central venous thrombosis (CVT).

METHODS

A retrospective, single institution review was performed of children with IF who were dependent on parenteral nutrition with known CVT between 2006 and 2017. Frequency of catheter-related complications including infection, occlusion, and breakage were compared 18months prior to and after starting AC. Thrombus resolution during anticoagulation was also determined. Data were analyzed using Poisson regression. p-Values <0.05 were considered significant.

RESULTS

Eighteen children had ≥1 CVT, with the subclavian vein most commonly thrombosed (44%). All children were treated with low molecular weight heparin, and 6 patients (33%) had clot resolution on re-imaging while receiving AC. Bloodstream infections decreased from 7.9 to 4.4 per 1000 catheter days during AC (p=0.01), and the number of infections requiring catheter replacement decreased from 3.0 to 1.0 per 1000 catheter days (p=0.01). There were no significant differences in line occlusions or breakages.

CONCLUSION

Anticoagulation for children with intestinal failure and central venous thrombosis may prevent thrombus propagation, and decrease blood stream infections and line replacements. Further research is needed to determine optimal dosing and duration of therapy.

LEVEL OF EVIDENCE

III; Retrospective Comparative Study.

Systemic treatments for the prevention of venous thrombo-embolic events in paediatric cancer patients with tunnelled central venous catheters

BACKGROUND

Venous thrombo-embolic events (VTEs) occur in 2.2% to 14% of paediatric cancer patients and cause significant morbidity and mortality. The malignant disease itself, the cancer treatment and the presence of central venous catheters (CVCs) increase the risk of VTE.

OBJECTIVES

The primary objective of this review was to investigate the effects of preventive systemic treatments in paediatric cancer patients with tunnelled CVCs on (a)symptomatic VTE. Secondary objectives of this review were to investigate adverse effects of systemic treatments for the prevention of (a)symptomatic VTE in paediatric cancer patients with tunnelled CVCs; and to investigate the effects of systemic treatments in the prevention of (a)symptomatic VTE with CVC-related infection in paediatric cancer patients with tunnelled CVCs.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, Issue 8 2012), MEDLINE (1966 to August 2012) and EMBASE (1966 to August 2012). In addition, we searched reference lists from relevant articles and conference proceedings of the International Society for Paediatric Oncology (SIOP) (from 2006 to 2011), the American Society of Clinical Oncology (ASCO) (from 2006 to 2011), the American Society of Hematology (ASH) (from 2006 to 2011) and the International Society of Thrombosis and Haematology (ISTH) (from 2006 to 2011). We scanned the International Standard Randomised Controlled Trial Number (ISRCTN) Register and the National Institute of Health (NIH) Register for ongoing trials (www.controlled-trials.com) (August 2012), and we contacted the authors of eligible studies if additional information was required.

SELECTION CRITERIA

Randomised controlled trials (RCTs) and controlled clinical trials (CCTs) comparing systemic treatments to prevent venous thrombo-embolic events (VTEs) in paediatric cancer patients with tunnelled CVCs with a control intervention or no systemic treatment. For the description of adverse events, cohort studies were eligible for inclusion.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies, extracted data and performed risk of bias assessment of included studies. Analyses were performed according to the guidelines of the Cochrane Handbook for Systematic Reviews of Interventions.

MAIN RESULTS

Three RCTs and three CCTs (including 1291 children) investigated the prevention of VTE (low molecular weight heparin (LMWH) n = 134, antithrombin (AT) supplementation n = 37, low-dose warfarin n = 31, cryoprecipitate and/or fresh frozen plasma (FFP) supplementation n = 240, AT supplementation and LMWH n = 41). AT, cryoprecipitate and FFP were supplemented only in cases of AT or fibrinogen deficiency. Of the six included RCTs/CCTs, five investigated the prevention of VTE compared with no intervention (n = 737), and one CCT compared AT supplementation and LMWH with AT supplementation (n = 71). All studies had methodological limitations, and clinical heterogeneity between studies was noted.We found no significant effects of systemic treatments compared with no intervention in preventing (a)symptomatic VTE and no differences in adverse events (such as major and/or minor bleeding; none of the studies reported thrombocytopenia, heparin-induced thrombocytopenia (HIT), heparin-induced thrombocytopenia with thrombosis (HITT), death as a result of VTE, removal of CVC due to VTE, CVC-related infection, and post-thrombotic syndrome (PTS)) between experimental and control groups. Two studies with comparable participant groups and interventions were included for meta-analyses (n = 182). In the experimental group, 1/68 (1.5%) children were diagnosed with symptomatic VTE, as were 4/114 (3.5%) in the control group (best case scenario: risk ratio (RR) 0.65, 95% confidence interval (CI) 0.09 to 4.78). These studies also evaluated asymptomatic CVC-related VTE: In the experimental group, 22/68 (32.4%) were diagnosed with asymptomatic VTE, as were 35/114 (30.7%) in the control group (best case scenario: RR 1.02, 95% CI 0.40 to 2.55). Heterogeneity was substantial for this analysis: I(2) = 73%.The attribution of LMWH to AT supplementation resulted in a significant reduction in symptomatic VTE (Fisher's exact test, two-sided P = 0.028) without bleeding complications; asymptomatic VTE, thrombocytopenia, HIT, HITT, death as a result of VTE, removal of CVC due to VTE, CVC-related infection and PTS were not assessed.Four cohort studies were included for the evaluation of adverse events. Three studies provided information on bleeding episodes: One participant developed an ischaemo-haemorrhagic stroke. One study provided information on other adverse events: None occurred.

AUTHORS' CONCLUSIONS

We found no significant effects of systemic treatments compared with no intervention in preventing (a)symptomatic VTE in paediatric oncology patients with CVCs. However, this could be a result of the low number of included participants, which resulted in low power. In one CCT, which compared one systemic treatment with another systemic treatment, we identified a significant reduction in symptomatic VTE with the addition of LMWH to AT supplementation.All studies investigated the prevalence of major and/or minor bleeding episodes, and none found a significant difference between study groups. None of the studies reported thrombocytopenia, HIT, HITT, death as a result of VTE, removal of CVC due to VTE, CVC-related infection or PTS among participants.On the basis of currently available evidence, we are not able to give recommendations for clinical practise. Additional well-designed international RCTs are needed to further explore the effects of systemic treatments in preventing VTE. Future studies should aim for adequate power with attainable sample sizes. The incidence of symptomatic VTE is relatively low; therefore, it might be necessary to select participants with thrombotic risk factors or to investigate asymptomatic VTE instead.

Rare but serious complications of central line insertion

Discussions on the complications of central venous catheterization in children typically focus on infectious and the more common mechanical complications of pneumothorax, hemothorax, or thrombosis. Rare complications are often more life-threatening, and inexperience may compound the problem. Central venous catheter complications can be broken down into early or late, depending on when they occur. The more serious complications are typically mechanical and occur early, but delayed presentations of pericardial effusions, cardiac tamponade, and pleural effusions may be of equal severity, and delay in diagnosis can be catastrophic. Careful insertion techniques, as well as continued vigilance in the correct position and function of central venous catheters, are imperative to help prevent serious complications.

Catheter-Related Central Venous Thrombosis: The Development of a Nationwide Consensus Paper in Italy

Catheter-related central venous thrombosis is a serious complication in patients who need long-term venous access. Though scientific data and clinical experience are steadily increasing, many uncertainties still exist about several aspects of this complication, including etiology, pathogenesis, diagnosis, management, and prevention of this complication. The GAVeCeLT (the Italian Study Group for Long Term Central Venous Access) promoted a nationwide consensus, and 12 experts reviewed systematically all the available literature. A preliminary document was presented and discussed during a specific Consensus Meeting, in front of a panel of more than 80 experts (representing different health professions and disciplines). This led to a prefinal document, which was presented to more than 800 health professionals. After peer review by an external board of experts, the final document was prepared. In this article, methodology and results of the consensus are presented.

Recombinant urokinase is safe and effective in restoring patency to occluded central venous access devices: a multiple-center, international trial

BACKGROUND

The treatment of choice for central venous access device (CVAD) occlusion is intracatheter thrombolysis, which has been reported to reestablish patency in up to 80% of cases. However, these salient results have only been achieved in highly selected CVAD subgroups such as nontunneled devices in adult patients, devices with recent occlusion, and in partially occluded devices through which fluid can still be infused (withdrawal occlusions). Less is known about the success of intracatheter thrombolysis in the broader range of CVAD malfunction encountered in clinical practice, especially in those devices that are totally occluded.

OBJECTIVE

This multiple-center, open-label study was performed to test the hypothesis that a new recombinant urokinase (r-UK, urokinase alfa) is safe and effective in reestablishing patency in a large unselected cohort of occluded CVADs.

METHODS

Pediatric and adult patients with any type of CVAD occlusion of any duration were treated with 5000 IU/mL intracatheter r-UK. Lumen patency was assessed after 5, 15, and 30 mins; a second dose of r-UK was instilled if the catheter remained occluded after 30 mins.

RESULTS

A total of 903 r-UK instillations were performed in 878 patients (age range, 16 days to 96 yrs). Overall, instillation of r-UK successfully restored total catheter patency (all treated lumens) to 75% of CVADs (681 of 902). Patency was restored to at least one occluded lumen in 79% of devices (712 of 902). Patency was restored equally in catheters with total occlusion (76%) as in catheters with only withdrawal occlusion (75%). The median +/- sd time to patency was 15 +/- 20.8 mins (range, 5-203 mins).

CONCLUSION

The use of a new r-UK, 5000 IU/mL, is safe and effective for the restoration of patency to occluded CVADs.

Upper extremity deep venous thrombosis: interventional management

Upper extremity deep venous thrombosis, previously thought to be a relatively innocuous disorder in comparison to lower extremity deep venous thrombosis, has recently begun to receive the attention it merits. Its optimal management remains controversial despite the development of several new techniques and devices which allow more rapid removal of thrombus and treatment of underlying venous stenotic disease. The following article provides a framework to discuss its treatment, with the emphasis on endovascular management.

Central venous catheter occlusion and thrombosis

Central venous catheters are widely used in children with critical illness and chronic disease. These devices are often essential in the delivery of medications and intravenous fluids and in hemodynamic monitoring. Central venous catheter occlusion and thrombosis are common problems in patients using these devices. This article reviews the background, pathophysiology, and incidence of catheter occlusion and catheter-related thrombosis. Diagnostic, preventive, and treatment strategies, along with future research directions, are addressed.

Superior vena caval syndrome: color flow Doppler detection of collateral venous channels

Thrombosis of the superior vena cava (SVC) is an important clinical problem that requires prompt diagnosis. Confirmation of suspected SVC syndrome requires the use of an imaging study to document the obstruction and presence of collateral venous channels. Echocardiography is often used to evaluate suspected SVC obstruction; however, previous methods have allowed only indirect detection of collateral flow. We describe 3 patients with SVC obstruction in whom color flow Doppler allowed direct demonstration of collateral venous channels.

Thrombus on indwelling central venous catheters: the histopathology of "Fibrin sheaths"

PURPOSE

Central venous catheters (CVC) may fail for many reasons, though "fibrin sheaths" blocking catheter ports are usually implicated. We examined the sheaths removed from dialysis catheters to determine their histopathology.

METHODS

Ten catheter strippings were performed and the removed material was studied grossly and microscopically.

RESULTS

The histologic specimens showed thrombus both with and without a proteinaceous sheath.

CONCLUSION

Dialysis catheters fail because of thrombus formation. This can occur in either the absence or presence of a protein coating on the catheter, the so-called "fibrin sheath."

Combined thrombolytic and anticoagulant therapy for venous thrombosis in children

OBJECTIVES

To evaluate safety, efficacy, and outcome after combination thrombolytic and anticoagulant therapy.

STUDY DESIGN

An open nonrandomized clinical protocol with prospective standardized monitoring and data collection. Children with a documented first episode of deep vein thrombosis were treated with urokinase 4400 U/kg load and per hour with unfractionated heparin at 10 U/kg/h. At 48 hours heparin infusions were increased to achieve a therapeutic level for 5 days. Children were given therapeutic warfarin for at least 3 months. Outcome was assessed at 48 hours and > or =1 year with history, physical examination, high-resolution imaging, and Doppler ultrasonography +/- impedance and photo plethysmography.

RESULTS

Thirty-two children were treated. There was 1 thrombotic death, 1 nonfatal thrombus progression, and 1 pulmonary embolism. At 48 hours half of the children showed substantial clot lysis, and on follow-up these children had complete resolution and had no symptoms. Three children with poor early clot lysis had recurrent thromboemboli, pulmonary embolism, or both, 2 had limb pain and swelling, and 2 had asymptomatic swelling. Two children had minor bleeding, whereas systemic reactions were common.

CONCLUSIONS

Combination therapy in children (urokinase and unfractionated heparin) was safe and efficacious. A prospective, randomized, controlled study in children is needed.

Catheter-induced thrombus in the superior vena cava diagnosed by transesophageal echocardiography

BACKGROUND

To present the role of transesophageal echocardiography (TEE) in the diagnosis and management of catheter-related superior vena cava thrombosis.

CASE HISTORY

A 42-year-old woman with severe Crohn's disease presented with septic shock and pulmonary embolism three weeks after emergency laparotomy and ileocolic resection for small-bowel perforation with peritonitis. Cardiopulmonary evaluation with ECG, pulmonary artery catheter and TEE demonstrated no evidence of acute myocardial ischemia or ventricular dysfunction; hemodynamic indices were consistent with severe sepsis. TEE revealed a large sheathing thrombus surrounding a central venous catheter used for parenteral nutrition. A spiral CT scan of the chest confirmed multiple peripheral pulmonary emboli. Treatment consisted of systemic anticoagulation and antibiotics. To avoid further pulmonary embolism, the central venous catheter was not removed until six days later under TEE monitoring, which revealed that the thrombus was firmly adherent to the superior vena cava. The patient made an uneventful recovery and was discharged from hospital on long-term anticoagulant therapy.

CONCLUSION

In a case of catheter-induced superior vena cava thrombosis with septicemia and pulmonary embolism, bedside TEE was very helpful to make the correct diagnosis early, assess thrombus size during anticoagulation, and monitor cardiac performance and thrombus disposition during central venous catheter removal.

Prevention of central venous catheter associated thrombosis using minidose warfarin in patients with haematological malignancies

Thrombosis is a well-recognized complication following insertion of central venous catheters and is associated with significant morbidity. In an attempt to reduce line-associated thrombosis, 108 consecutive patients with haematological malignancies were commenced on prophylactic 'minidose' warfarin, 1 mg/d, at the time of line insertion. This group of patients were compared with a historic group of 115 consecutive patients who had not received warfarin. Clinically-suspected venous thrombosis was confirmed by Doppler ultrasound or venography. Patients taking prophylactic warfarin had their prothrombin time measured three times per week with the aim of maintaining an INR <1.6. Five (5%) of the 108 patients who received minidose warfarin developed a thrombosis, at a median of 72 d (range 5-166) from the time of catheter insertion. In the 115 patients who were not anticoagulated 15 (13%) developed a catheter-associated thrombosis at a median of 16 d (range 1-35). There was a significant reduction in line-associated thrombosis in patients receiving warfarin (P=0.03). These data suggest that minidose warfarin reduces the incidence of central venous catheter related thrombosis in patients with haematological malignancies.