Catheter-Related Thrombosis in Cancer Patients: Pathophysiology, Diagnosis, and Management

Risk factors analysis and the establishment of nomogram prediction model for PICC-related venous thrombosis in patients with lymphoma: a double-center cohort-based case-control study

Objective

The objective of this study is to examine the risk factors associated with the occurrence of PICC-Related Venous Thrombosis (PICC-RVTE) in individuals diagnosed with lymphoma, as well as to develop a predictive risk nomogram model.

Methods

A total of 215 patients with lymphoma treated at Yunnan Provincial Tumor Hospital from January 2017 to December 2020 were retrospectively evaluated as the training cohort; 90 patients with lymphoma treated at the Department of Oncology of the First People's Hospital of Anning, Affiliated to Kunming University of Science and Technology during the January 2021 to September 2023 were evaluated as the validation cohort. Independent influencing factors were analyzed by logistic regression, a nomogram was developed and validated, and the model was evaluated using internal and external data cohorts for validation.

Results

A total of 305 lymphoma patients were selected and 35 (11.48%) PICC-RVTE occurred, the median time was 13 days. The incidence within 1-2week was 65.71%. Multivariate analysis suggested that the activity amount, thrombosis history(within the last 12 months), ATIII, Total cholesterol and D-dimer levels were independently associated with PICC-RVTE, and a nomogram was constructed based on the multivariate analysis. ROC analysis indicated good discrimination in the training set (area under the curve [AUC] = 0.907, 95%CI:0.850-0.964) and the testing set (AUC = 0.896, 95%CI: 0.782-1.000) for the PICC-RVTE nomogram. The calibration curves showed good calibration abilities, and the decision curves indicated the clinical usefulness of the prediction nomograms.

Conclusions

Patients should be advised to undergo color Doppler ultrasound system testing within two week after the implantation of a PICC catheter to detect PICC-RVTE at an early stage. The validated nomogram can be used to predict the risk of catheter-related thrombosis (CRT) in patients with lymphoma who received at least one chemotherapy after PICC catheterization, no bleeding tendency, no recent history of anticoagulant exposure and no severe heart, lung, renal insufficiency. This model has the potential to assist clinicians in formulating individualized treatment strategies for each patient.

The 5 most frequently asked questions about factor Xa inhibitors

Direct oral anticoagulants (DOACs) are commonly used oral factor Xa inhibitors in recent years. However, in some special clinical situations, the appropriate use of these anticoagulants may be of concern. In this article, we address the 5 commonly asked questions regarding their use for the treatment of venous thromboembolism, including in the setting of obesity, renal impairment, gastrointestinal (GI) malignancy, catheter-related thrombosis, and drug-drug interactions. Data on the use of DOACs in the presence of significant obesity or renal failure are mainly observational. Some DOACs are shown to have an increased risk of bleeding in patients with unresected luminal GI malignancy but not others, so selection of appropriate patients is the key. Furthermore, literature on the use of DOACs for catheter-related thrombosis or when drug-drug interactions are of concern is limited, and more research is welcome.

Complications of surgical port-a-cath implantation in paediatric patients: a single institution experience

Background

Implantable vascular access devices (IVADs) provide durable routes for administering long-term treatments in patients. However, their associated complications pose a problem. One technique variation that can influence complication rates is the method of securing the IVADs, which is either by ligation or a purse-string suture.

Objective

To compare the two port-a-cath securing techniques, ligation and purse string, in terms of complication rates and types.

Study design

We prospectively included 67 paediatric patients who had port-a-cath insertions secured either by ligation or a purse-string suture at Salmaniya Medical Complex in Bahrain from January 2018 to June 2021. We recorded demographics, diagnoses, port-a-cath site of insertion and securing technique, operative time, follow-up duration, and complications. Patients who had previous port-a-cath insertions or other chemotherapy lines were excluded.

Results

Port-a-caths were secured by ligation in 35 cases and by a purse-string suture in 32 cases. There were 58.9% males and 41.8% females; sex was not correlated with complications (P = 0.11). Patients’ ages ranged from 2 months to 13 years. The overall complication rate of port-a-cath insertions was 16.42%. Complications occurred in 25.7% of ligation-secured port-a-caths and 6.3% of purse-string-secured port-a-caths. In the ligation-secured IVADs, complications included malfunction, infections, removal difficulty and blockage, malposition, and haematoma. Meanwhile, only leakage occurred in the purse-string-secured IVADs.

Conclusion

The port-a-cath securing technique was significantly correlated with complication rates. The complication types and rates in purse-string-secured catheters were lower than those reported in the literature. Leakage was the only complication that occurred in purse-string-secured port-a-caths.

Frequency and risk factors for thrombosis in acute myeloid leukemia and high-risk myelodysplastic syndromes treated with intensive chemotherapy: a two centers observational study

The frequency of thrombosis in AML has been evaluated only in a few studies and no validated predictive model is currently available. Recently, DIC score was shown to identify patients at higher thrombotic risk. We aimed to evaluate the frequency of thromboembolism in AML patients treated with intensive chemotherapy and to assess the ability of genetic and clinical factors to predict the thrombotic risk. We performed a retrospective observational study including 222 newly diagnosed adult AML (210) and high-risk MDS (12), treated with intensive chemotherapy between January 2013 and February 2020. With a median follow-up of 44 months, we observed 50 thrombotic events (90% were venous, VTE). The prevalence of thrombosis was 22.1% and the 6-months cumulative incidence of thrombosis was 10%. The median time to thrombosis was 84 days and 52% of the events occurred within 100 days from AML diagnosis. Khorana and DIC score failed to stratify patients according to their thrombotic risk. Only history of a thrombotic event (p = 0.043), particularly VTE (p = 0.0053), platelet count above 100 × 10⁹/L at diagnosis (p = 0.036) and active smoking (p = 0.025) significantly and independently increased the risk of thrombosis, the latter particularly of arterial events. AML genetic profile did not affect thrombosis occurrence. Results were confirmed considering only thromboses occurring within day 100 from diagnosis. DIC score at diagnosis, but not thrombosis, was independently associated with reduced survival (p = 0.004). Previous VTE, platelet count above 100 × 10⁹/L and active smoking were the only factors associate with increased thrombotic risk in AML patients treated intensively, but further studies are needed to validate these results.

Development and Validation of a New Clinical Prediction Model of Catheter-Related Thrombosis Based on Vascular Ultrasound Diagnosis in Cancer Patients

Background: Central venous catheters are convenient for drug delivery and improved comfort for cancer patients, but they also cause serious complications. The most common complication is catheter-related thrombosis (CRT). Objectives: This study aimed to evaluate the incidence and risk factors for CRT in cancer patients and develop an effective prediction model for CRT in cancer patients. Methods: The development of our prediction model was based on a retrospective cohort (n = 3,131) from the National Cancer Center. Our prediction model was confirmed in a prospective cohort from the National Cancer Center (n = 685) and a retrospective cohort from the Hunan Cancer Hospital (n = 61). The predictive accuracy and discriminative ability were determined by receiver operating characteristic (ROC) curves and calibration plots. Results: Multivariate analysis demonstrated that sex, cancer type, catheter type, position of the catheter tip, chemotherapy status, and antiplatelet/anticoagulation status at baseline were independent risk factors for CRT. The area under the ROC curve of our prediction model was 0.741 (CI: 0.715-0.766) in the primary cohort and 0.754 (CI: 0.704-0.803) and 0.658 (CI: 0.470-0.845) in validation cohorts 1 and 2, respectively. The model also showed good calibration and clinical impact in the primary and validation cohorts. Conclusions: Our model is a novel prediction tool for CRT risk that accurately assigns cancer patients into high- and low-risk groups. Our model will be valuable for clinicians when making decisions regarding thromboprophylaxis.

Efficacy and clinical outcome of the port-a-cath in children: a tertiary care-center experience

Background

Implanted vascular access devices play an essential role in the management of pediatric patients. The objectives of this study were to assess our experience with port-a-cath insertion in pediatric patients, report its complications, and compare open versus percutaneous approaches.

Methods

We performed a retrospective cohort study, including 568 patients who underwent port-a-cath insertion between 2013 and 2019 in our center. We grouped the patients according to the technique of insertion into two groups: group 1 (n = 168) included patients who had the open approach and group 2 (n = 404) included patients who had the percutaneous technique. (p < 0.001).

Results

Patients in group 1 were younger (4.10 ± 3.45 years) compared to patients in group 2 (5.47 ± 3.85 years). The main indications of insertion were hematological malignancy 57.74% (n = 328), solid organ malignancy 25.18% (n = 143), pure hematological diseases 5.46% (n = 31), metabolic diseases 2.64% (n = 15), and others for poor vascular access 8.8% (n = 50). The most common site for insertion in group 1 was the left external jugular (n = 136; 82.98%) and the left subclavian in group 2 (n = 203; 50.25%). Two hundred and two patients had a central line before catheter insertion (36.6%). Complications during insertion were comparable between both groups (p = 0.427). The catheter got stuck in 6 patients; all required additional incision and two needed venotomy. The most common reason to remove the catheter was the completion of the treatment (63.69% and 61.14%, in groups 1 and 2, respectively). The duration of the catheter was comparable between the two groups (13.14 ± 14.76 vs. 14.44 ± 14.04 months in group 1 vs.2; p = 0.327).

Conclusions

Open and percutaneous port-a-cath insertions are safe in children with chronic diseases. Port-a-cath improved patients’ management, and complications are infrequent. The most common complications are infection and catheter malfunction, which can be managed without catheter removal in some patients.

A retrospective analysis of risk factors associated with catheter-related thrombosis: a single-center study

BACKGROUND

Catheter-related thrombosis may lead to catheter infections and failure, further deep venous thrombosis, and pulmonary embolism. Recognizing the risk factors for catheter-related thrombosis is extremely important to inform the development of catheter care guidelines.

METHODS

Data were collected from a total of 1,532 patients who had undergone venous catheterization, including indwelling catheterization from 19 March 2019 to 30 March 2019 in the Sun Yat-sen Memorial Hospital. The factors for which data were to be collected included the patients' physical characteristics, catheter-related factors, and catheter care-related factors. Logistic regression analysis, the chi-squared test, Fisher's exact test, and the t-test were used to analyze the data.

RESULTS

Of the 1,532 patients studied, 28 developed intraductal thrombi, and of the factors analyzed, malignancy, a catheterization history, a history of thrombophilia, surgery during the week before catheterization, the catheterization duration, and anticoagulant therapy were significant risk factors associated with catheter-related thrombosis (all p < 0.05). There were no significant associations between the catheter brand, the number of lumens, the insertion direction, or the factors associated with catheter care and catheter-related thrombosis (all p > 0.05).

CONCLUSION

Our study incorporated clear and systematic risk factors associated with catheter-related thrombosis. Malignancy, history of thrombophilia, history of catheterization, surgery during the week before catheterization, and catheterization duration were associated with increased risks of catheter-related thrombosis. Prophylactic anticoagulation was effective for preventing and treating catheter-related thrombosis.

Risk factors, risk assessment, and prognosis in patients with gynecological cancer and thromboembolism

OBJECTIVE

This study aimed to investigate a suitable risk assessment model to predict deep vein thrombosis (DVT) in patients with gynecological cancer.

METHODS

Data from 212 patients with gynecological cancer in the Affiliated Tumor Hospital of Guangxi Medical University were retrospectively analyzed. Patients were risk-stratified with three different risk assessment models individually, including the Caprini model, Wells DVT model, and Khorana model.

RESULTS

The difference in risk level evaluated by the Caprini model was not different between the DVT and control groups. However, the DVT group had a significantly higher risk level than the control group with the Wells DVT or Khorana model. The Wells DVT model was more effective for stratifying patients in the DVT group into the higher risk level and for stratifying those in the control group into the lower risk level. Receiver operating curve analysis showed that the area under the curve of the Wells DVT, Khorana, and Caprini models was 0.995 ± 0.002, 0.642 ± 0.038, and 0.567 ± 0.039, respectively.

CONCLUSION

The Wells DVT model is the most suitable risk assessment model for predicting DVT. Clinicians could also combine the Caprini and Wells DVT models to effectively identify high-risk patients and eliminate patients without DVT.

Role of Chemoports in Children with Hematological/Solid Tumor Malignancies - Technical Implications and Complications: An Institutional Experience

Aim

The aim of this retrospective analysis was to identify the variously related complications and to study preventive and therapeutic measures for these complications.

Materials and Methods

A total of 72 catheters were inserted in 69 patients (mean follow-up of 1140 days) from December 2002 to May 2017. Sixty-four children were diagnosed to have hematological malignancies, and five children had solid tumors. The youngest child was 2 months of age, and the oldest was 15 years, 5 months. Records were analyzed retrospectively for the age, indication, route of insertion, and postoperative complications. A protocol-based insertion and postinsertion handling by trained nursing staff/doctors were instituted, including a periodic training program for those concerned.

Results

Chemoport-related complications were infection in 3 (4.16%), necessitating port removal in one patient. The rest were managed by antibiotic-lock therapy. The other problems were catheter tip occlusion in 1 (1.38%) and extravasation in two patients (2.77%) leading to a sterile collection around the port chamber. An unsightly scar in 4 (5.55%) and granuloma formation at scar site in 1 (1.38%) patient were noted.

Conclusion

Totally implantable chemoports are preferred in children with solid and hematological malignancies because of decreased pain, the rate of infection, and ability to maintain patency for the long term. Despite significant advantages over other types of central venous access, chemoports have their own complications. It was also noted that the rate of complications could be minimized by periodic training of all the personnel concerned and following protocol-based handling of ports.

A narrative review of long-term central venous access devices for the intensivist

Long-term central venous access devices are increasingly prevalent and consequently often encountered by intensivists. This review introduces the different types of long-term central venous access devices, outlines their potential utility, examines potential complications associated with their use and outlines an approach to the management of these complications.

Thrombotic complications and tip position of transjugular chronic dialysis catheter scheduled into superior vena cava: Findings on HR-MRCP and HR-T2WI

BACKGROUND

Catheter-related thrombotic complications(TCs) can occur during the long term use of a chronic dialysis catheter (CDC), including fibrin sheath (FS), mural thrombosis (MT), venous thrombosis (VT), and intraluminal clots (IC), which has not been reported with MRI. The aim of our study was to evaluate the determination of catheter tip position (TP) and resolution of TCs in patients with transjugular CDC scheduled into the superior vena cava using high resolution magnetic resonance cholangiopancreatography (HR-MRCP) and T2-weighted imaging (HR-T2WI).

METHODS

The study protocol was approved by the local Research Ethics Committee. Informed consent was obtained from all patients. In total, 41 consecutively enrolled transjugular CDC patients with suspected catheter dysfunction were scanned with HRMRCP and HR-T2WI. The distance from the top to the tip of the catheter and the presence and nature of catheter TCs were assessed by 2 experienced radiologists. Chest x-ray was taken within 1 to 2 days and CDC was withdrawn within 3 to 10 days from those patients with TCs identified by HR-MRI.

RESULTS

A total of 38 subjects successfully underwent HR-MRI, including 13 normal and 25 with TCs (fibrin sheath [FS]: n = 21, mural thrombosis [MT]: n = 7, venous thrombosis [VT]: n = 3, intraluminal clots [IC]: n = 4). There was no significant difference between HR-MRCP and chest x-ray in catheter TP determination (P = .124). Normal catheter appeared as "double eyes" on HR-T2WI and "double tracks" on HR-MRCP. TCs appeared as follows: FS displayed as a "thin ring" (<1mm) around the catheter, MT as patchy hyperintensity and VT as a "thick ring" (>5mm) on HR-T2WI. Unilateral IC appeared as a "single eye" on HR-T2WI and a "single track" on HR-MRCP (n = 3). Bilateral IC appeared as neither "eye" nor "track" (n = 1). Catheter withdrawal confirmed FS (n = 16), MT (n = 6), VT (n = 1), and IC (n = 4).

CONCLUSION

HR-MRCP and HR-T2WI are promising methods for visualizing TP and TCs in CDC patients, and are helpful in adjusting the treatment plan and avoiding the risk of pulmonary embolism.

Right atrial thrombus associated with subclavian catheter developed due to total parenteral nutrition application

Central venous catheterization as a frequent routine clinical procedure may have significant complications. Mechanical complications may occur during catheter placement, whereas thromboembolic and infectious complications can be seen during follow-up. Total parenteral nutrition (TPN) associated central venous catheterizations may result in early mechanical complications and thrombotic and infectious complications in the long term.

This paper describes a patient diagnosed as mitochondrial neurogastrointestinal encephalomyopathy requiring long-term central venous catheterization for TPN implementation, who had an infected thrombus on the catheter tip resected by cardiac surgery.

Central venous catheter-related thrombosis in senile male patients: New risk factors and predictors

Central venous catheterization (CVC)-related venous thrombosis is a common but serious clinical complication, thus prevention and treatment on this problem should be extensively investigated. In this research, we aimed to investigate the incidence rate of CVC-related venous thrombosis in senile patients and give a further discussion on the related risk factors and predictors. A total of 324 hospitalized senile male patients subjected to CVC were selected. Retrospective investigation and analysis were conducted on age, underlying diseases, clinical medications, catheterization position and side, catheter retention time, and incidence of CVC-related venous thrombosis complications. Basic laboratory test results during catheterization and thrombogenesis were also collected and analyzed. Among the 324 patients, 20 cases (6.17%) of CVC-related venous thrombosis were diagnoseds. The incidence rate of CVC-related venous thrombosis in subclavian vein catheterization was significantly lower than that in femoral vein catheterization (P<0.01) and that in internal jugular vein catheterization (P<0.05). No statistically significant difference was found between femoral vein catheterization and internal jugular vein catheterization (P<0.05). Previous venous thrombosis history (P<0.01), high lactate dehydrogenase level (P<0.01), low high-density lipoprotein (HDL) level (P<0.05), and low albumin level (P<0.05) were found as risk factors or predictors of CVC-related venous thrombosis in senile male patients. Subclavian vein catheterization was the most appropriate choice among senile patients to decrease the incidence of CVC-related venous thrombosis. Previous venous thrombosis history, high lactate dehydrogenase level, low HDL level, and low albumin level were important risk factors in predicting CVC-related venous thrombosis.

An engineered micropattern to reduce bacterial colonization, platelet adhesion and fibrin sheath formation for improved biocompatibility of central venous catheters

Background

Catheter-related bloodstream infections (CRBSIs) and catheter-related thrombosis (CRT) are common complications of central venous catheters (CVC), which are used to monitor patient health and deliver medications. CVCs are subject to protein adsorption and platelet adhesion as well as colonization by the natural skin flora (i.e. Staphylococcus aureus and Staphylococcus epidermidis). Antimicrobial and antithrombotic drugs can prevent infections and thrombosis-related complications, but have associated resistance and safety risks. Surface topographies have shown promise in limiting platelet and bacterial adhesion, so it was hypothesized that an engineered Sharklet micropattern, inspired by shark-skin, may provide a combined approach as it has wide reaching anti-fouling capabilities. To assess the feasibility for this micropattern to improve CVC-related healthcare outcomes, bacterial colonization and platelet interactions were analyzed in vitro on a material common for vascular access devices.

Methods

To evaluate bacterial inhibition after simulated vascular exposure, micropatterned thermoplastic polyurethane surfaces were preconditioned with blood proteins in vitro then subjected to a bacterial challenge for 1 and 18 h. Platelet adhesion was assessed with fluorescent microscopy after incubation of the surfaces with platelet-rich plasma (PRP) supplemented with calcium. Platelet activation was further assessed by monitoring fibrin formation with fluorescent microscopy after exposure of the surfaces to platelet-rich plasma (PRP) supplemented with calcium in a flow-cell. Results are reported as percent reductions and significance is based on t-tests and ANOVA models of log reductions. All experiments were replicated at least three times.

Results

Blood and serum conditioned micropatterned surfaces reduced 18 h S. aureus and S. epidermidis colonization by 70% (p ≤ 0.05) and 71% (p < 0.01), respectively, when compared to preconditioned unpatterned controls. Additionally, platelet adhesion and fibrin sheath formation were reduced by 86% and 80% (p < 0.05), respectively, on the micropattern, when compared to controls.

Conclusions

The Sharklet micropattern, in a CVC-relevant thermoplastic polyurethane, significantly reduced bacterial colonization and relevant platelet interactions after simulated vascular exposure. These results suggest that the incorporation of the Sharklet micropattern on the surface of a CVC may inhibit the initial events that lead to CRBSI and CRT.

Early-onset Thrombosis of Internal Jugular Vein Associated with Introducer Catheter for Heart Catheterization in Cardiac Surgery

Purpose

In cardiac surgery, Swan-Ganz catheter (SGC) is often necessary and is inserted before the intervention through an introducer catheter. Catheter-related thrombosis (CRT) is a frequent complication of this procedure and often remains subclinical. The aims of this prospective cohort study were to determinate the incidence of CRT after positioning an SGC through an introducer and to identify factors relating to their occurrence.

Methods

One-hundred and sixteen cardiac surgery patients underwent ultrasound examination of the thoracic-cervical vessels, before and after introducer catheter removal. Data about drugs infused through the introducer catheter were also collected.

Results

The incidence of internal jugular vein CRT was 26.7%, corresponding to 70.5 cases per 1,000 catheter days. The incidence of “fibrin sleeve” was 28.4%. All introducer catheter tips lay in the brachiocephalic vein or in the upper third of the superior vena cava. The incidence of CRT was not associated with duration of the placement of the introducer catheter (average 3.9±2 days) or the SGC (average of 2.4±1.7 days). Infusion of total parenteral nutrition and dextran showed a significantly increased risk of thrombosis in both univariate and multivariate analyses. An overly proximal position of the introducer catheter tip was strongly associated with CRT incidence.

Conclusions

The presence of an introducer catheter for SGC, even for a short time, is associated with a high incidence of early-onset CRT. This incidence is significantly related to the catheter tip being positioned in the brachiocephalic vein and to its use as a central venous access.

Do children with central venous line (CVL) dysfunction have increased risk of symptomatic thromboembolism compared to those without CVL-dysfunction, while on cancer therapy?

Background

Thromboembolism (TE) and infection are two common complications of central venous line (CVL). Thrombotic CVL-dysfunction is a common, yet less studied, complication of CVL. Two retrospective studies have reported significant association of CVL-dysfunction and TE. Recent studies indicate association of CVL-related small clot with infection. Infection is the most common cause of non-cancer related mortality in children with cancer. We and others have shown reduced overall survival (OS) in children with cancer and CVL-dysfunction compared to those without CVL-dysfunction. Despite these observations, to date there are no prospective studies to evaluate the clinical significance of CVL-dysfunction and it’s impact on the development of TE, infection, or outcome of children with cancer.

Study design

This is a prospective, analytical cohort study conducted at five tertiary care pediatric oncology centers in Ontario. Children (≤ 18 years of age) with non-central nervous system cancers and CVL will be eligible for the study. Primary outcome measure is symptomatic TE and secondary outcomes are infection, recurrence of cancer and death due to any cause. Data will be analyzed using regression analyses.

Discussion

The overall objective is to delineate the relationship between CVL-dysfunction, infection and TE. The primary aim is to evaluate the role of CVL-dysfunction as a predictor of symptomatic TE in children with cancer. We hypothesize that children with CVL-dysfunction have activation of the coagulation system resulting in an increased risk of symptomatic TE. The secondary aims are to study the impact of CVL-dysfunction on the rate of infection and the survival [OS and event free survival (EFS)] of children with cancer. We postulate that patients with CVL-dysfunction have an occult CVL-related clot which acts as a microbial focus with resultant increased risk of infection. Further, CVL-dysfunction by itself or in combination with associated complications may cause therapy delays resulting in adverse outcome.

This study will help to identify children at high risk for TE and infection. Based on the study results, we will design randomized controlled trials of prophylactic anticoagulant therapy to reduce the incidence of TE and infection. This in turn will help to improve the outcome in children with cancer.

Central venous line dysfunction is an independent predictor of poor survival in children with cancer

Central venous line (CVL) dysfunction (mainly from thrombotic occlusion) is a frequent, but relatively less-studied complication compared with infection and thromboembolism (TE). In adults with cancer, TE results in poor outcome. We evaluated the impact of CVL-dysfunction and TE on overall survival (OS) and event-free survival (EFS) in children with noncentral nervous system cancer (n=358). CVL-dysfunction was defined as persistent or recurrent difficulty of blood draw and/or infusion. Event was defined as cancer relapse, second malignancy, or death due to any cause. OS and EFS were estimated using Kaplan-Meier method and survival curves compared using log-rank test. Hazard ratios (HR) were calculated using the Weibull regression model. Diagnosis of TE (n=43, 12%) had no effect on the OS and EFS. Children with CVL-dysfunction (n=74, 21%) had shorter 5- and 10-year EFS compared with children without CVL-dysfunction (P=0.029 and P=0.027). Multiple regression analyses, adjusting for age, sex, diagnostic era, TE, and cancer type identified CVL-dysfunction as an independent determinant of 5-year OS (HR 1.87; 95% confidence interval, 1.02-3.42; P=0.043) and EFS (HR 1.96; 95% confidence interval, 1.23-3.41; P=0.018). Although the etiology of adverse impact of CVL-dysfunction on survival is unknown, its prevention and prompt treatment may improve outcome from cancer in children. Further prospective studies are recommended.

Prevention of VTE in nonsurgical patients: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines

BACKGROUND

This guideline addressed VTE prevention in hospitalized medical patients, outpatients with cancer, the chronically immobilized, long-distance travelers, and those with asymptomatic thrombophilia.

METHODS

This guideline follows methods described in Methodology for the Development of Antithrombotic Therapy and Prevention of Thrombosis Guidelines: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines in this supplement.

RESULTS

For acutely ill hospitalized medical patients at increased risk of thrombosis, we recommend anticoagulant thromboprophylaxis with low-molecular-weight heparin (LMWH), low-dose unfractionated heparin (LDUH) bid, LDUH tid, or fondaparinux (Grade 1B) and suggest against extending the duration of thromboprophylaxis beyond the period of patient immobilization or acute hospital stay (Grade 2B). For acutely ill hospitalized medical patients at low risk of thrombosis, we recommend against the use of pharmacologic prophylaxis or mechanical prophylaxis (Grade 1B). For acutely ill hospitalized medical patients at increased risk of thrombosis who are bleeding or are at high risk for major bleeding, we suggest mechanical thromboprophylaxis with graduated compression stockings (GCS) (Grade 2C) or intermittent pneumatic compression (IPC) (Grade 2C). For critically ill patients, we suggest using LMWH or LDUH thromboprophylaxis (Grade 2C). For critically ill patients who are bleeding or are at high risk for major bleeding, we suggest mechanical thromboprophylaxis with GCS and/or IPC at least until the bleeding risk decreases (Grade 2C). In outpatients with cancer who have no additional risk factors for VTE we suggest against routine prophylaxis with LMWH or LDUH (Grade 2B) and recommend against the prophylactic use of vitamin K antagonists (Grade 1B).

CONCLUSIONS

Decisions regarding prophylaxis in nonsurgical patients should be made after consideration of risk factors for both thrombosis and bleeding, clinical context, and patients' values and preferences.

Thrombolytic therapy for central venous catheter occlusion

BACKGROUND

Long-term central venous catheters have improved the quality of care for patients with chronic illnesses, but are complicated by obstructions which can result in delay of treatment or catheter removal.

DESIGN AND METHODS

This paper reviews thrombolytic treatment for catheter obstruction. Literature from Medline searches using the terms "central venous catheter", "central venous access device" OR "central venous line" associated with the terms "obstruction", "occlusion" OR "thrombolytic" was reviewed. Efficacy of thrombolytic therapy, central venous catheter clearance rates and time to clearance were assessed.

RESULTS

Alteplase, one of the current therapies, clears 52% of obstructed catheters within 30 min with 86% overall clearance (after 2 doses, when necessary). However, newer medications may have higher efficacy or shorter time to clearance. Reteplase cleared 67-74% within 30-40 min and 95% of catheters overall. Occlusions were resolved in 70 and 83% of patients with one and 2 doses of tenecteplase, respectively. Recombinant urokinase cleared 60% of catheters at 30 min and 73% overall. Alfimeprase demonstrated rapid catheter clearance with resolution in 40% of subjects within 5 min, 60% within 30 min, and 80% within 2 h. Additionally, urokinase prophylaxis decreased the incidence of catheter occlusions from 16-68% in the control group to 4-23% in the treatment group; in some studies, rates of catheter infections were also decreased in the urokinase group.

CONCLUSIONS

Thrombolytic agents successfully clear central venous catheter occlusions in most cases. Newer agents may act more rapidly and effectively than currently utilized therapies, but randomized studies with direct comparisons of these agents are needed to determine optimal management for catheter obstruction.

Thrombosis and cancer: spectrum of multidetector CT findings in oncologic patients with thromboembolic disease. A pictorial review

This article is a reasoned pictorial review illustrating the many faces of thrombotic and embolic disease developing in the cancer patient. From a clinical point of view, we particularly point out the importance of properly identifying this occurrence in its various presentations. From a radiological point of view, special emphasis is given to the wide spectrum of multidetector CT findings, to the clues of benign and malignant thrombus diagnosis, and to the potential interpretative pitfalls.

Central venous device-related thrombosis as imaged with MDCT in oncologic patients: prevalence and findings

BACKGROUND

Venous thrombosis is a common occurrence in cancer patients, developing spontaneously or in combination with indwelling central venous devices (CVD).

PURPOSE

To analyze the multidetector CT (MDCT) prevalence, appearance, and significance of catheter-related thoracic venous thrombosis in oncologic patients and to determine the percentage of thrombi identified in the original reports.

MATERIAL AND METHODS

Five hundred consecutive patients were considered. Inclusion criteria were: presence of a CVD; availability of a contrast-enhanced MDCT; and cancer history. Exclusion criteria were: direct tumor compression/infiltration of the veins; poor image quality; device tip not in the scanned volume; and missing clinical data. Seventeen (3.5%) out of the final 481 patients had a diagnosis of venous thrombosis.

RESULTS

Factors showing the highest correlation with thrombosis included peripherally-inserted CVD, right brachiocephalic vein tip location, patient performance status 3, metastatic stage disease, ongoing chemotherapy, and longstanding CVD. The highest prevalence was in patients with lymphoma, lung carcinoma, melanoma, and gynecologic malignancies. Eleven out of 17 cases had not been identified in the original report.

CONCLUSION

CVD-related thrombosis is not uncommon in cancer patients and can also be observed in outpatients with a good performance status and a non-metastatic disease. Thrombi can be very tiny. Radiologists should be aware of the possibility to identify (or overlook) small thrombi.

Risk factors for catheter-related thrombosis (CRT) in cancer patients: a patient-level data (IPD) meta-analysis of clinical trials and prospective studies

BACKGROUND

Knowledge of independent, baseline risk factors for catheter-related thrombosis (CRT) may help select adult cancer patients who are at high risk to receive thromboprophylaxis.

OBJECTIVES

We conducted a meta-analysis of individual patient-level data to identify these baseline risk factors.

PATIENTS/METHODS

MEDLINE, EMBASE, CINAHL, CENTRAL, DARE and the Grey literature databases were searched in all languages from 1995 to 2008. Prospective studies and randomized controlled trials (RCTs) were eligible. Studies were included if original patient-level data were provided by the investigators and if CRT was objectively confirmed with valid imaging. Multivariate logistic regression analysis of 17 prespecified baseline characteristics was conducted. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were estimated.

RESULTS

A total sample of 5636 subjects from five RCTs and seven prospective studies was included in the analysis. Among these subjects, 425 CRT events were observed. In multivariate logistic regression, the use of implanted ports as compared with peripherally implanted central venous catheters (PICCs), decreased CRT risk (OR, 0.43; 95% CI, 0.23-0.80), whereas past history of deep vein thrombosis (DVT) (OR, 2.03; 95% CI, 1.05-3.92), subclavian venipuncture insertion technique (OR, 2.16; 95% CI, 1.07-4.34) and improper catheter tip location (OR, 1.92; 95% CI, 1.22-3.02), increased CRT risk.

CONCLUSIONS

CRT risk is increased with use of PICCs, previous history of DVT, subclavian venipuncture insertion technique and improper positioning of the catheter tip. These factors may be useful for risk stratifying patients to select those for thromboprophylaxis. Prospective studies are needed to validate these findings.

Thrombotic complications in adult patients with lymphoma: a meta-analysis of 29 independent cohorts including 18 018 patients and 1149 events

Thrombotic complications in hematologic malignancies have important clinical implications. In this meta-analysis we sought to obtain accurate estimates of the thrombotic risk in lymphoma patients. Articles were searched in electronic databases and references. Eighteen articles were identified (29 cohorts, 18 018 patients and 1149 events). Pooled incidence rates (IRs) were calculated by the use of a method based on the exact maximum likelihood binomial distribution. The global IR of thrombosis was 6.4% (95% confidence interval [CI] 6.0%-6.8%). The global IRs of venous or arterial events were 5.3% (95% CI, 5.0%-5.7%) and 1.1% (95% CI, 0.9%-1.2%), respectively. The IR of thrombosis observed in subjects with non-Hodgkin lymphoma (NHL) was 6.5% (95% CI, 6.1%-6.9%), significantly greater than that observed for patients with Hodgkin lymphoma (4.7%; 95% CI, 3.9%-5.6%). Within NHL, patients with high-grade disease had a greater risk of events (IR 8.3%; 95% CI, 7.0%-9.9%) than low-grade disease (IR 6.3%; 95% CI, 4.5%-8.9%). This meta-analysis shows that the IR of thrombosis in lymphoma patients is quite high, especially in those with NHL at an advanced stage of the disease. These results may help better defining lymphoma populations at high thrombotic risk, to whom prophylactic approaches could be preferentially applied.

Thrombotic complications of tunneled central lines in children with malignancy

BACKGROUND

The total rate of thrombotic complications caused by tunneled central lines (TCL) is still not known, as are the long-term consequences.

AIM OF THE STUDY

Estimation of a rate of thrombotic complications in children with TCL and malignancy and Doppler ultrasound assessment of blood flow after TCL removal.

MATERIALS AND METHODS

One hundred twenty-four children were enrolled for the study. Heparin lock was used as a prophylaxis for line occlusion. The rate and type of thrombotic events associated with TCL were analyzed in all patients. In children without an earlier history of thrombosis, a Doppler ultrasound examination was carried out after TCL removal.

RESULTS

In 45.2% of patients at least 1 thrombotic event occurred. These events were TCL lumen thrombosis (42.8% of patients) and subclavian vein thrombosis (2.4% of patients). In 37 patients Doppler ultrasound was carried out and revealed an abnormal blood flow in the vein that was examined in 59.5% of them.

CONCLUSIONS

The total rate of thrombotic complications in children with TCL and malignancy is high. A substantial proportion of thrombotic complications can be clinically silent. The use of a heparin lock once a week seems far from effective in preventing thrombotic events in patients with TCL. The TCL life span has no influence on the rate of thrombotic events.

Diagnosis and initial treatment of venous thromboembolism in patients with cancer

PURPOSE

Venous thromboembolism (VTE) is a common complication of cancer and its therapy. The purpose of this article is to review the diagnosis and initial treatment of VTE in the patient with cancer.

METHODS

I conducted a survey of the English-language literature on topics relevant to the diagnosis and initial treatment of VTE in patients with cancer.

RESULTS

Patients with cancer are at increased risk for VTE because of the presence of multiple risk factors for thrombotic disease. The most common signs and symptoms of VTE as well as the utility of clinical prediction rules and D-dimer testing in the diagnosis of VTE in the patient with cancer are reviewed. Duplex ultrasound and computer tomography angiography are the primary objective diagnostic modalities for VTE. Low molecular weight heparin is the preferred initial therapy for VTE. Until further data emerge, thrombolysis and vena cava filters should be reserved for patients in whom anticoagulation is insufficient or contraindicated. Outpatient management is feasible for carefully selected patients with cancer with deep vein thrombosis (DVT) and low-risk pulmonary embolism. Anticoagulation is the preferred initial therapy for cancer patients with central venous catheter-associated DVT, calf DVT, and unsuspected VTE.

CONCLUSION

Optimal initial management of VTE in patients with cancer entails maintaining a high index of suspicion for thrombotic disease, confirming diagnostic suspicions with objective testing and evidence-based use of anticoagulation, and adjunctive therapeutic modalities (thrombolysis, vena cava interruption, venous stenting). Further investigation of initial diagnostic and treatment strategies for VTE focusing on patients with cancer are warranted.

Risk of thrombosis and infections of central venous catheters and totally implanted access ports in patients treated for cancer

INTRODUCTION

Thrombosis and infections are well known complications of central venous catheters and totally implanted access ports. These complications lead to increased costs due to prolonged hospitalisation, increased antibiotics use and need for replacement. The objectives of the study were to document the occurrence of catheter related thrombosis and infections in patients with central venous catheters and totally implanted chest ports in cancer patients and to investigate whether factor V Leiden is a risk factor for catheter related thrombosis.

MATERIALS AND METHODS

Between February 2002 and November 2004, 43 patients with central venous catheter or totally implanted access port were followed up to document the occurrence of catheter related thrombosis and infections. Patients received chemotherapy either for haematological malignancy or for solid tumours. Factor V Leiden (R506Q) was determined by restriction fragment length polymorphism analysis. Follow-up period ended in April 2007.

RESULTS

Catheter related thrombosis occurred in 4 patients (4/43; 9.3%) with a totally implanted access port. None of the 3 patients with factor V Leiden had catheter related infection or thrombosis. Catheter related infections occurred in 15 patients: 10 patients (23.3%; 10/43) with central venous catheter and 5 patients (11.6%; 5/43) with totally implanted access ports. Time to infection was 32.5 days in the central venous catheter group compared to 88 days in the totally implanted access port group.

CONCLUSION

A higher incidence of catheter related infections was observed in patients with central venous catheters in contrast to patients with totally implanted access ports were venous thrombosis was more frequent.

Management of occlusion and thrombosis associated with long-term indwelling central venous catheters

Long-term central venous catheters (CVCs) are important instruments in the care of patients with chronic illnesses, but catheter occlusions and catheter-related thromboses are common complications that can result from their use. In this Review, we summarise management of these complications. Mechanical CVC occlusions need cause-specific treatment, whereas thrombotic occlusions usually resolve with thrombolytic treatment, such as alteplase. Prophylaxis with thrombolytic flushes might prevent CVC infections and catheter-related thromboses, but confirmatory studies and cost-effectiveness analysis of this approach are needed. Risk factors for catheter-related thromboses include previous catheter infections, malposition of the catheter tip, and prothrombotic states. Catheter-related thromboses can lead to catheter infection, pulmonary embolism, and post-thrombotic syndrome. Catheter-related thromboses are usually diagnosed by Doppler ultrasonography or venography and treated with anticoagulation therapy for 6 weeks to a year, dependent on the extent of the thrombus, response to initial therapy, and whether thrombophilic factors persist. Prevention of catheter-related thromboses includes proper positioning of the CVC and prevention of infections; anticoagulation prophylaxis is not currently recommended.

Prevention and management of central venous catheter occlusion and thrombosis in children with cancer

BACKGROUND

The views and clinical practice of children's cancer units were surveyed regarding management of central venous catheter (CVC) occlusion (CVC-occlusion), CVC-related thrombosis (CVC-thrombosis) and thromboembolism (CVC-thromboembolism).

PROCEDURE

A questionnaire was sent to all 22 United Kingdom Children's Cancer Study Group centres, requesting information about their views of the importance of, and their practices regarding, prophylaxis, diagnosis and treatment of CVC-occlusion/thrombosis.

RESULTS

Twenty (91%) centres responded. Eighty percent, 80% and 70%, respectively, stated that CVC-occlusion, CVC-thrombosis and CVC-thromboembolism were clinically important concerns. All centres used heparinised saline flushes as prophylaxis against CVC-occlusion, with little variation (</=30% centres) in frequency, volume and heparin concentration. Symptoms or signs suggesting partial CVC-occlusion, total CVC-occlusion, or CVC-thrombosis/thromboembolism were always investigated in 20%, 55% and 85% of centres, respectively, but with considerable variability in the nature and sequence of investigations performed, which included (depending on the clinical scenario) chest X-ray, contrast linography or venography, ultrasonography, echocardiography and magnetic resonance venography. A fibrinolytic lock was administered before investigation of CVC-occlusion in 75% of centres. Although 45%, 60% and 80%, respectively, always treated partial CVC-occlusion, total CVC-occlusion or CVC-thrombosis/thromboembolism, the type and order of treatments differed greatly between centres, especially for CVC-thrombosis/thromboembolism, in which CVC removal, systemic anticoagulation (heparin or warfarin), local or systemic fibrinolysis, or thrombectomy were performed in at least some centres.

CONCLUSIONS

The clinical practice of UKCCSG centres regarding prevention, investigation and treatment of CVC-occlusion/thrombosis varies greatly. Additional trials should facilitate development of evidence-based guidelines.

Clinical dilemmas: vascular access devices

OBJECTIVES

To present an overview of clinical dilemmas regarding maintenance care and managing complications of vascular access devices (VADs).

DATA SOURCES

Current research and published literature.

CONCLUSION

The use of VADs has increased over the past three decades because they have proven to be an effective and convenient method of accessing the venous system. The difficulty of maintaining VADs during the course of treatment however, continues to be a challenge resulting in practice dilemmas.

IMPLICATIONS FOR NURSING PRACTICE

Although VADs have been in use for more than 30 years, no universal standard of maintenance care exists. Research is still needed to establish evidence-based practice regarding the care and maintenance of VADs.

Quantitative analysis of catheter roughness induced by cutting and manipulation: a potential prothrombotic risk

Thrombosis is a major complication of central venous access devices, its incidence depending on material, diameter, tip position, and tip surface. Catheters are usually cut to the appropriate length for accurate positioning. Cutting is not recommended, however, as rough surfaces can serve as a nidus for thrombosis. The present study was performed to assess the roughness of catheter tips provided by various manufacturers versus the roughness once cut and handled. Three types of catheters (Hickman, Port-a-Cath, and Per Q Cath) were cut by scissors, iris scissors, or scalpel, and were handled with debakey forceps, a needle driver, adson with teeth or adson without teeth, to determine the damage created on the catheter. The uncut manufactured tip was compared as a control. Scanning electron microscopy was used for imaging of all samples, and roughness was quantified by atomic force microscopy for the cutting methods. Qualitative results by scanning electron microscopy showed that scalpel-cut and manufactured ends appeared smoother relative to those cut with scissors or iris scissors. This complemented the roughness analysis by atomic force microscopy. Catheters handled by debakey forceps and adsons with teeth showed most roughness, visible as deep holes or a grainy surface when observed by high-magnification scanning electron microscopy. Overall, the smoothest result was produced by scalpel, followed by the manufactured end, scissors, and iris scissors. Handling should be minimized, and use of adsons with teeth, needle drivers and debakey forceps should be avoided, as they can leave permanent damage. Adsons without teeth appeared the least damaging.

Fatal postoperative pulmonary embolism in mild haemophilia

The use of thromboprophylaxis in patients with haemophilia receiving factor replacement is often not considered necessary, but remains an area of debate. In this report we describe a patient with mild haemophilia A, who underwent major pelvic surgery. He had several underlying risk factors associated with the development of thromboembolism, and ultimately died as a direct consequence of multiple pulmonary emboli. The need for thromboprophylaxis and the risk balance ratio should always be considered in patients with bleeding disorders if they fall into what would otherwise be high-risk category for hospital acquired venous thromboembolism.

Venous Thromboembolism in the ICU and Reversal of Bleeding on Anticoagulants

Venous thromboembolic disease is a very common complication in the ICU. This article reviews incidence, prevention, and therapy related to venous thromboembolism, including both deep venous thrombosis and pulmonary embolism. Special diagnostic and treatment considerations in the ICU setting are highlighted. The increased use of antithrombotic agents has led to an increased number of patients who experience bleeding complications on anticoagulant therapy. This review also addresses the methods of reversing various anticoagulants.