Groshong catheter-associated subclavian venous thrombosis

Comparison of heparinized saline and 0.9% sodium chloride for maintaining central venous catheter patency in healthy dogs

Background

The purpose of this study was to determine whether heparinized saline (HS) would be more effective in maintaining the patency of central venous catheters (CVCs) in dogs compared to 0.9% sodium chloride. This was a prospective randomized blinded study conducted at a University Veterinary Teaching Hospital.

Methods

A total of 24 healthy purpose-bred dogs were randomized into two groups: a treatment and a control group. A CVC was placed in the jugular vein of each dog. Each dog in the treatment group had their CVC flushed with 10 IU/mL HS, while dogs in the control group had their CVC flushed with 0.9% sodium chloride every 6 h for 72 h. Immediately prior to flushing, each catheter was evaluated for patency by aspiration of blood. The catheter site was also evaluated for phlebitis, and a rectal temperature was obtained in each dog every 6 h. Prothrombin (PT) and activated partial thromboplastin (aPTT) times were evaluated prior to the administration of any flush solution. Results were then compared to values obtained 72 h later.

Results

All CVCs in both groups were patent after 72 h, which was demonstrated by aspiration of blood and ease of flushing the catheter. Two CVCs in the 0.9% sodium chloride group had a negative aspiration at hour 12 and 36, respectively. One CVC in the HS group had a negative aspiration at hour 18. Signs of phlebitis occurred in three dog: two in the 0.9% sodium chloride group and one in the HS group. No dog was hyperthermic (>103 °F). Two catheters were inadvertently removed by dogs in the HS group during the study. There were no significant differences in catheter patency, incidence of phlebitis, or incidence of negative aspirations between both groups. aPTT and PT values remained within the normal reference range for all dogs in both groups. Ultimately, 0.9% sodium chloride was as effective as 10 IU/mL HS in maintaining the patency of CVCs for up to 72 h in healthy dogs. Further evaluation in clinical patients is warranted.

The development of central venous thrombosis in hemodialyzed patients is associated with catheter tip depth and localization

INTRODUCTION

The aim of our work was to analyze the incidence of tunneled hemodialysis catheters-related thrombosis in hemodialyzed patients depending on catheter tip depth and position and to evaluate the impact of other established risk factors responsible for development of central venous thrombosis.

METHODS

The presence of central vein thrombosis, location, and the depth of the catheter tip was reviewed by two experienced radiologists. All patients with suspected central venous thrombosis had factor V Leiden, lupus anticoagulant, and cardiolipin antibodies checked (acIgM and acIgG) and were evaluated with cat-scan venography.

FINDINGS

A total of 68 tunneled hemodialysis catheters were analyzed with CT venography for central venous thrombosis. There were no signs of central venous thrombosis when catheter tips were placed in the right atrium. There was significantly higher number of catheter tips located on the vein wall than located centrally in patients with central venous thrombosis. Higher percentage of central venous thrombosis, smaller number of tips placed in the right atrium, higher values of IgM cardiolipin antibodies, and higher number of patients with positive factor V Leiden mutation were found in group of patients with catheter tips located on vein wall.

DISCUSSION

Higher incidence of central venous thrombosis in patients with the catheter tip placed on the vein wall is a consequence of a catheter tip depth proximal of the right atrium. Increased factor V Leiden mutation and acIgM values in these patients should be observed as a result of the vein stasis caused by inappropriate catheter tip depth and localization.

Right or left? Side selection for a totally implantable vascular access device: a randomised observational study

BACKGROUND

Totally implantable vascular access device (TIVAD)-related complications interfere in the anticancer treatment and increase medical expenses. We examined whether the implantation side of central line TIVADs is associated with the occurrence of thrombotic or occlusion events.

METHODS

We enrolled patients with cancer who required central line TIVADs and randomised them to receive the TIVAD implantation on either the left or right side. The primary endpoint was the occurrence of catheter-related thrombotic or occlusion events.

RESULTS

We randomised 240 patients, of which 235 received TIVAD implantation according to the protocol. In the per-protocol cohort, 117 and 118 patients received implantation on the left and right sides, respectively. Catheter-related thrombotic or occlusion events occurred in 9 (4%) patients, accounting for 0.065 events per 1000 catheter-days. Between the patients with left- and right-sided implantations, the occurrence rates (P=0.333) and the time from catheter implantation to the occurrence of thrombotic or occlusion events (P=0.328) were both similar. In the multivariate analysis, the side of implantation remained unassociated with the occurrence of thrombotic or occlusion events.

CONCLUSIONS

The side of central line TIVAD implantation was not associated with the occurrence of catheter-related thrombotic or occlusion events in patients with cancer.

Principles and Strategies for Monitoring Home Parenteral Nutrition

Patients who cannot ingest adequate calories to maintain body weight via their gastrointestinal tract may require parenteral nutrition (PN) at home. As with any therapy, the patient must be evaluated to determine if the home PN (HPN) is effective and the patient is free of complications. This review discusses specific items to monitor for HPN patients. Parameters to monitor can be divided into those used to determine effectiveness and those used to prevent complications of HPN. In addition, potential HPN-associated complications can be divided into those that occur with short- or long-term PN administration. Specific items to monitor are discussed within this framework.

Reduced risk of pulmonary emboli in children treated with long-term parenteral nutrition

BACKGROUND & AIMS

Pulmonary embolism (PE) is a complication of parenteral nutrition (PN) with a prevalence of 35% in children. In 2003 new intravenous lipid emulsions (ILEs) with MCT, olive and/or fish oil in addition to soybean oil were introduced. The aim was to compare the incidence of PE before and after introduction.

METHODS

327 surveillance ventilation-perfusion (V/Q) scintigraphies from 68 children aged 0.3-15 years, treated with PN from 1993 to 2010, were retrospectively reviewed. Rate of PE/1000 central venous catheter (CVC) days, number of children with PE pre- and post-introduction of ILEs were compared. Multivariate analyses were performed for risk factors.

RESULTS

Twenty-two (32%) children (19/42 before 2003 and 3/26 after 2003, p = 0.007) had at least one episode of PE. Thirty seven (11%) episodes of PE were detected accounting for a mean of 0.2/1000 CVC days prior to 2003 and 0.05/1000 CVC days after 2003, p = 0.04. Regression analysis indicated that higher content of ILE/infusion (p = 0.045) and frequency of ILE of >3 nights/week were associated with more PE (p = 0.001). New ILEs were associated with lower risk (p = 0.003).

CONCLUSION

With a four-fold fall in incidence with new ILE, PE remains a complication. We recommend 12-18 monthly surveillance with lung perfusion scan and anticoagulants if PE is diagnosed.

Totally implantable central venous catheters for chemotherapy: experience with 793 patients

OBJECTIVE

To retrospectively study the results obtained with the implementation of totally implantable catheters in patients undergoing chemotherapy.

METHODS

815 totally implantable catheters placed in 793 patients undergoing chemotherapy regimen, preferably using the right cephalic vein. We evaluated early and late complications.

RESULTS

The retrospective analysis showed an average duration of 339 days of the catheters. In 733 (90%) catheters there was no observe complication. Among early complications we observed one pneumothorax, one bad positioning of the catheter, one arterial puncture, one bleeding, one hemothorax and hemomediastinum and six hematomas in the implantation site. As for late complications, there were 35 catheter-related infections ten, infections in the surgical site, six obstructions and 20 thromboses. We removed 236 catheters, 35 due to complications and 201 by the end of treatment.

CONCLUSION

totally implantable catheters for chemotherapy are a safe means for the administration of substances, in view of the low number of complications observed in this study.

Catheter-related thrombosis in cancer patients

Central venous catheters are commonly used in haematology departments for the administration of chemotherapy, blood products and parenteral nutrition in patients with haematological malignancy. Thrombosis is a recognized complication of such devices especially in oncology patients. Catheter-related thrombi (CRT) may lead to pulmonary embolism and infection, as well as catheter failure and potential delays in treatment. The vast majority of CRT are asymptomatic, thus a high index of suspicion is required in making the diagnosis. Doppler ultrasound or venography may be employed to identify CRT. Once confirmed, the initiation of treatment is a balance between the risks of anticoagulation against potential complications of CRT. A number of risk factors for CRT are discussed along with an overview of catheter types, their appropriate choice and intravascular positioning.

Review article: the management of long-term parenteral nutrition

BACKGROUND

Home parenteral nutrition (HPN) is currently the management of choice for patients with chronic intestinal failure.

AIM

To summarise the major issues in delivering long-term parenteral nutrition (>3 months) and assess outcome as per complications, mortality and quality of life. To assess the evidence for the therapeutic use of trophic factors such as teduglutide and to review evolving therapeutic options in the treatment of chronic intestinal failure.

METHODS

A literature search using PubMed and MEDLINE databases was performed.

RESULTS

Safe delivery of HPN relies upon individualised formulations of parenteral nutrition administered via carefully maintained central venous catheters by trained patients or carers, supported by a skilled multidisciplinary team. Early diagnosis and treatment of complications including catheter-associated blood stream infection (reported incidence 0.14-0.83 episodes/patient-year on HPN) and central venous thrombosis (reported incidence 0.03 episodes/patient-year) is important to minimise mortality and morbidity. There is a significant variation in the reported incidence of both hepatobiliary complications (19-75%) and advanced liver disease (0-50%). Five-year survival rates in large centres are reported between 60% and 78% with survival primarily related to underlying diagnosis. Long-term survival remains higher on HPN than with intestinal transplantation. The role of intestinal lengthening procedures is yet to be validated in adults.

CONCLUSIONS

Home parenteral nutrition delivered by skilled nutrition teams has low incidences of catheter-related complications. Most deaths relate to the underlying disease. Therapies such as teduglutide and small bowel transplantation appear promising, but home parenteral nutrition appears likely to remain the bedrock of management in the near term.

Catheter thrombosis and superior/inferior vena cava syndrome are rare complications of long term parenteral nutrition

The objective of this study was to determine the incidence of catheter thrombosis and superior/inferior vena cava (SVC IVC ) syndrome in a large population of patients receiving home total parenteral nutrition (TPN), using retrospective data collection and analysis. 527 patients including 138 children who were discharged on home TPN and followed in the UCLA home TPN program for a minimum of one week between April, 1973 and October, 1991. There was a total of 1154 years of patients follow-up, including 241 years in children. Fifty-seven patients (11%) developed 81 episodes of catheter thrombosis excluding SVC IVC syndrome with an incidence of 0.07 episodes per catheter year. The median catheter duration prior to thrombosis was 7 months. Twenty-one thromboses occured in children with an incidence of 0.09 per catheter year. Eleven percent of thrombotic episodes were associated with catheter sepsis. Thirty-nine percent of patients had a PTT less than control values. Twenty-two patients including 6 children developed SVC IVC syndrome with an incidence of 0.02 per catheter year. SVC IVC syndrome was not associated with catheter sepsis in any patient. Sixty-eight percent of patients had catheter thrombosis at some point prior to developing SVC IVC syndrome. It is concluded that catheter-related thrombotic events are rare complications of home TPN and are uncommonly associated with infection. However, we recommend warfarin anticoagulation following an initial thrombotic event, in the absence of catheter malposition, for all such patients as long as they maintain a central venous catheter.

Central Venous Catheter-related Complications in Patients with Hematological Malignancies: A Retrospective Analysis of Risk Factors and Prophylactic Measures

We retrospectively analyzed the incidence of thrombotic and infectious complications in relation with the use of central venous catheters (CVCs), in a series of patients with hematological malignancies and low platelet and leucocyte counts.

PATIENTS AND METHODS

126 patients with hematological malignancies were analyzed. A total of 207 CVCs were implanted: 137 centrally (CICCs) and 70 peripherally (PICCs). The median duration of the CVCs was 19 days for a total of 4051 catheter-days. Antithrombotic prophylaxis was unfractionated heparin (UFH), 2,500 IU daily by 24 h continuous infusion in 169 CVCs, low molecular weight heparin (LMWH), 3,800 IU daily by single bolus intravenous injection (i.v.) in 21 and warfarin in one. No prophylaxis was given in 16 CVCs. Thrombotic complications developed in 15.5% of the CVCs (7.9 events/1000 catheter days), and the frequency of infectious complications was 10.6% (5.2 events/1000 catheter days). On multivariate analysis thromboses were more frequent and earlier with PICCs than CICCs (p = 0.0001), and in patients on UFH (16.6%) than in LMWH prophylaxis (4.7%), but the last difference was not statistically significant. In conclusions the incidence of thrombotic complications in our series was comparable to that observed in non-thrombocytopenic patients and was significantly higher in those carrying PICC than CICC (p = 0.0001). There were fewer thrombotic events in the patients receiving i.v. LMWH prophylaxis than in those receiving i.v. UFH. The use of anticoagulants was safe and not associated with hemorrhages.

Risk factors for upper limb deep vein thrombosis associated with the use of central vein catheter in cancer patients

Deep vein thrombosis of upper limb is a common complication of CVC in patients with cancer. In these patients the risk factors for CVC-related thrombosis are not completely defined. The purpose of this study was to identify the risk factors for CVC-related thrombosis in patients included in a randomized, double-blind, placebo-controlled study aimed at assessing the efficacy and safety of enoxaparin for the prophylaxis of CVC-related thrombosis. CVC-related thrombosis was screened by mandatory venography after 6 weeks of study treatment. A number of patient baseline characteristics were assessed as potential risk factors for CVC-related deep vein thrombosis. Crude associations between risk factors and clinical outcomes were assessed by chi(2) test or Fisher's exact test. Multiple logistic regression analysis was used to identify independent risk factors. A CVC-related thrombosis was found in 50 out of 310 patients (16.1%). At multiple logistic regression analysis, CVC tip misplaced in the upper half of superior vena cava (OR 4.05, 95%CI 1.64-10.02), left-sided CVC insertion (OR 2.29, 95%CI 1.01-5.51) and chest radiotherapy (OR 7.01, 95%CI 1.42-34.66) were independent risk factors for thrombosis. In addition to these risk factors, the presence of distant metastases (OR 9.36, 95%CI 1.53-57.05) increased the risk of thrombosis in patients who received placebo. An inadequate position of the CVC tip, left-sided CVC insertion and chest radiotherapy are independent risk factors for CVC-related thrombosis in cancer patients. Patients with distant metastases have an increased risk for thrombosis in absence of antithrombotic prophylaxis.

[Venous thromboembolism associated with long-term use of central venous catheters in cancer patients]

Increased incidence of cancers and the development of totally implanted venous access devices that contain their own port to deliver chemotherapy will lead to a greater than before numbers of central venous catheter-related thrombosis (CVCT). Medical consequences include catheter dysfunction and pulmonary embolism. Vessel injury caused by the procedure of CVC insertion is the most important risk factor for development of CVCT. This event could cause the formation of a fresh thrombus, which is reversible in the large majority of patients. In some cases, thrombus formation is not related to catheter insertion. The incidence of CVC-related DVT assessed by venography has been reported to vary from 30 to 60% but catheter-related DVT in adult patients is symptomatic in only 5% of cases. The majority of patients with CVC-related DVT is asymptomatic or has nonspecific symptoms: arm or neck swelling or pain, distal paresthesias, headache, congestion of subcutaneous collateral veins. In the case of clinical suspicion of CVC-related deep venous thrombosis (DVT), compressive ultrasonography (US), especially with doppler and color imaging, currently is first used to confirm the diagnosis. Consequently, contrast venography is reserved for clinical trials and difficult diagnostic situations. There is no consensus on the optimal management of patients with CVC-related DVT. Treatment of CVC-related VTE requires a five- to seven-day course of adjusted-dose unfractionated heparin or low molecular weight heparin (LMWH) followed by oral anticoagulants. Long-term LMWH that has been shown to be more effective than oral anticoagulant in cancer patients with lower limb DVT, could be used in these patients. The efficacy and safety of pharmacologic prophylaxis for CVC related thrombosis is not established and the last recommendations suggest that clinicians not routinely use prophylaxis to try to prevent thrombosis related to long-term indwelling CVCs in cancer patients. Additional studies performed in high risk populations with appropriate dosage and timing will help to define which patients could benefit from prophylaxis.

Association between inherited thrombophilic abnormalities and central venous catheter thrombosis in patients with cancer: a meta-analysis

BACKGROUND

The risk of deep vein thrombosis (DVT) is increased in cancer patients with central venous catheters (CVC). Factor (F)V Leiden and the G20210A prothrombin mutation (PTM) may play a role in causing catheter-related DVT in patients with cancer. However, information on the association between these thrombophilic abnormalities and CVC-related thrombosis are scarce.

PURPOSE

To assess the risk of CVC-related thrombosis associated with these two thrombophilic disorders.

METHODS

MEDLINE and EMBASE databases (up to March 2007); reference lists of retrieved articles. Studies comparing the prevalence of prothrombotic abnormalities in cancer patients with CVC-related thrombosis and in a control group of cancer subjects with CVC without thrombosis. Two reviewers independently selected studies and extracted study characteristics, quality and outcomes. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated for each trial and pooled.

RESULTS

Ten studies involving 1000 patients were included. The pooled OR for CVC-related thrombosis was 4.6 (95% CI: 2.6, 8.1) in patients with FV Leiden. The pooled OR for CVC-related thrombosis was 4.9 (95% CI: 1.7, 14.3) in patients with PTM. The estimated attributable risk of CVC-related thrombosis was 13.1% for FV Leiden and 4.5% for PTM.

CONCLUSION

Our meta-analysis suggests that the presence of FV Leiden and PTM is associated with CVC-related thrombosis.

Thromboses sur cathéter central chez le patient cancéreux

OBJECTIVES

Increased incidence of cancers and the development of totally implanted venous access devices that contain their own port to deliver chemotherapy will lead to a greater than before numbers of central venous catheter related thrombosis (CVCT). Medical consequences include catheter dysfunction and pulmonary embolism. Compared with lower extremity deep venous thrombosis (DVT) (3 d) and with non CVC associated thrombosis (5 d), CVCT is associated with an increased duration of hospitalisation (9 d). CVCT oftentimes leads to the need to replace such ports at an average cost of 4500 euros.

CURRENT KNOWLEDGE AND KEY POINTS

Vessel injury caused by the procedure of CVC insertion is the most important risk factor for development of CVCT. This event could cause the formation of a fresh thrombus, which is reversible in the large majority of patients. The incidence of CVC-related DVT assessed by venography has been reported to vary from 30 to 60% but catheter-related DVT in adult patients is symptomatic in only 5% of cases. The majority of patients with CVC-related DVT is asymptomatic or has non-specific symptoms: arm or neck swelling or pain, distal paresthesias, headache, congestion of subcutaneous collateral veins. In the case of clinical suspicion of CVC-related DVT, compressive ultrasonography (US), especially with Doppler and color imaging, currently is first used to confirm the diagnosis. The main criteria of color-Doppler US are visualization of mural thrombi or incompressibility of the veins. Consequently, contrast venography is reserved for clinical trials and difficult diagnostic situations. There is no consensus on the optimal management of patients with CVC-related DVT. Treatment of CVC-related VTE requires a 5- to 7-day course of adjusted-dose unfractionated heparin or LMWH followed by oral anticoagulants. Long-term LMWH that has been shown to be more effective than oral anticoagulant in cancer patients with lower limb DVT could be used in these patients. The optimal duration of oral anticoagulation treatment for CVC-related DVT is unknown, but patients with active cancer should be treated for at least 6 months or indefinitely.

FUTURE PROSPECTS AND PROJECTS

The efficacy and safety of pharmacologic prophylaxis for CVC related thrombosis is not established. Additional studies performed in high risk populations are needed to define if LMWH or oral anticoagulation is indicated in this clinical setting.

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.

Specific topics and complications of parenteral nutrition

BACKGROUND/AIMS

Total parenteral nutrition (TPN) has proven a tremendous advance in all disciplines in medicine but itself introduces a spectrum of possible complications related to both the parenteral nutritional solution as well as the technique of intravenous delivery. Our aim is to review the specific complications of TPN.

MATERIALS AND METHODS

This article presents a critical literature review of relevant topics in TPN-related complications-metabolic, infections, and nutrition related.

RESULTS

Special emphasis focuses on complications of TPN arising from thrombosis or infectious sequelae related to the central venous catheterization and metabolic complications involving the kidneys, bones, liver, and biliary tract.

CONCLUSIONS

Awareness and surveillance of TPN-related complications can prevent, potentially, some of these complications related to parenteral nutritional support.

Therapy Insight: venous-catheter-related thrombosis in cancer patients

Central venous catheters (CVCs) have improved the management of patients with cancer substantially, by facilitating chemotherapy and supportive therapy. The use of CVCs is associated with complications such as infection and upper-limb deep vein thrombosis (UL-DVT). The incidence of clinically overt UL-DVT related to the use of CVCs ranges between 2% and 4%. In the most recent study, the incidence of CVC-related thrombosis, as screened by venography, was approximately 18% in the absence of prophylaxis. In cancer patients with CVC-related UL-DVT, the incidence of clinically overt pulmonary embolism was between 15% and 25%, and the incidence of autopsy-proven pulmonary embolism was up to 50%. Pathogenic factors for CVC-related thrombosis include vessel injury caused by the CVC insertion procedure, venous stasis because of the indwelling CVC, and hypercoagulability associated with cancer. Recent studies have not confirmed a benefit for prophylaxis with antithrombotic agents for CVC-related thrombosis. The recommended treatment for CVC-related thrombosis is based on long-term anticoagulant therapy, with or without catheter removal.

Primary thromboprophylaxis for cancer patients with central venous catheters--a reappraisal of the evidence

Venous thromboembolism (VTE) is responsible for an estimated 25 000 deaths per annum in UK hospital practice. It is well established that many of these deaths could be prevented through the use of appropriate thromboprophylaxis. This issue is of particular relevance in oncology practice, where the risks of VTE and bleeding are both significantly higher than those observed in general medical patients. Cancer patients with in-dwelling central venous catheters (CVCs) are at particularly high risk of developing thrombotic complications. However, the literature has produced conflicting conclusions regarding the efficacy of using routine primary thromboprophylaxis in these patients. Indeed such is the level of confusion around this topic, that the most recent version of the American College of Chest Physicians (ACCP) guidelines published in 2004 actually reversed their previous recommendation (published in 2001). Nevertheless, minidose warfarin continues to be routinely used in many oncology centres in the UK. In this article, we have performed a systematic review of the published literature regarding the efficacy and the risks, associated with using thromboprophylaxis (either minidose warfarin or low-dose LMWH) in cancer patients with CVC. On the basis of this evidence, we conclude that there is no proven role for using such thromboprophylaxis. However, asymptomatic CVC-related venous thrombosis remains common, and further more highly powered studies of better design are needed in order to define whether specific subgroups of cancer patients might benefit from receiving thromboprophylaxis.

Guidelines for management of home parenteral support in adult chronic intestinal failure patients

Management of home parenteral support in adult benign but chronic intestinal failure patients requires a nutrition support team using disease-specific pathways. Education of patients to ensure they self manage home parenteral nutrition (HPN) is cornerstone to obtain minimal rate of technical complications and improvement in quality of life. Nutritive mixtures, compounded by pharmacists in single "all-in-one" bags, must be tailored according to the nutritional and intestinal status of individual patients with definition of macronutrients and water-electrolyte needs, respectively. Each PN cycle should be complete in essential nutrients to be nutritionally efficient and should have sufficient amounts of amino acids, dextrose, water, minerals, and micronutrients to avoid deficiency. When the nutritional goal is achieved, a minimum number of PN cycles per week should be implemented, guided ideally by digestive balance(s) (In-Out) of macronutrients and minerals of individual patients. Indeed, HPN is, in most cases, a complementary nonexclusive mode of nutritional support. In short gut patients--who represent 75% of chronic intestinal failure patients--encouraging enteral feeding decrease PN delivery and the risk of metabolic liver disease associated with HPN. In short gut patients with no severe renal impairment, blood citrulline dosage, in association with the remnant anatomy, is a tool to delineate transient from permanent intestinal failure. The latter group includes candidates for trophic gut factors and rehabilitative or reconstructive surgery, including intestinal transplantation. Thus, outcome improvement for intestinal failure patients needs intestinal failure teams having expertise in all medical and surgical aspects of this field.

Thromboembolic complications in children with cancer

Thrombosis is a significant problem in patients with cancer. The impact of thromboembolism in association with childhood cancer is not clearly defined. Similarly the information of prevention and management of thromboembolic events in children receiving cancer-therapy is limited. This review aims to examine current knowledge regarding the epidemiology, pathophysiology and management of thrombosis in association with cancer in children.

Thrombose symptomatique sur cathéter veineux central de longue durée en oncologie : un score de risque prédictif?

BACKGROUND

Central venous catheters are essential to management of cancer patients. Thrombotic complications are potentially severe, but it is difficult to prescribe systematically a prophylactic treatment. So it is necessary to identify the higher risk patients who need a prophylaxis.

AIM

To identify factors associated with the development of clinically significant venous thrombosis in cancer patients with long-term catheters.

METHODS

Monocentric prospective study about 5447 long-term central venous catheters inserted into patients receiving treatment for solid tumours (50% of breast cancers). Clinically significant catheter-related thromboses are confirmed by ultrasonography, phlebography or scanner.

RESULTS

The median duration of catheter use is 147 days. There are 135 clinically significant catheter-related thromboses. The risk for thrombosis is 0.1149 events per 1000 device days. The incidence of symptomatic thrombosis is 0.9% at 30 days, 1.36% at 60 days, 1.83% at 90 days and 2.25% at 120 days. The multivariate analysis shows that female sex, duration of insertion procedure (more than 25 minutes) and place of insertion (femoral place) are factors associated with clinically significant venous thrombosis. The right subclavian insertion causes less risk. The catheters with their tip too "high" in the superior vena cava are systematically changed, so that the position of the catheter tip does not appear as a risk factor in our study. The disease stage and the type of treatments are not well examined.

CONCLUSIONS

A predictive score can be made with the three risk factors that have been identified. Thanks to this score it is possible to determine the patients with higher risk for clinically significant catheter-related venous thrombosis. These patients must be more frequently watched over and must receive a prophylactic treatment. The best prophylaxis has to be determined.

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

Central venous catheters (CVCs) are commonly used in oncology patients. Up to 50% of CVCs are complicated by thrombosis within the catheter or the blood vessel. These thrombi are the result of local tissue damage, the catheter itself, and the thrombophilia of cancer. Frequent flushes with saline or heparin may reduce the frequency of catheter dysfunction but do not reduce the rate of deep venous thrombosis (DVT) in the catheterized blood vessel. Efforts to use prophylactic heparin or warfarin to reduce catheter-related DVT have not been rewarding.

Cancer and thrombosis: mechanisms and treatment

Standard venous thromboembolic event (VTE) treatment practices including the use of intravenous unfractionated heparin (UFH) for initial anticoagulation, oral warfarin for chronic anticoagulation, and the prescription of only 3 to 6 months total therapy may not be optimal in the setting of active cancer and ongoing anti-cancer therapy. Challenges of VTE management in cancer patients include heparin resistance due to excess circulating acute-phase proteins, increased recurrence rates during and following standard-intensity warfarin therapy, limited venous access to support therapeutic monitoring, and anticoagulation intensity-independent increased bleeding rates during anticoagulation. Bleeding during anticoagulation is of particular concern in the treatment of cancer patients with disease- or chemotherapy-related thrombocytopenia, central nervous system involvement, or recent invasive procedures. Low-molecular weight heparins (LMWH) have been shown to be at least as effective and safe for initial anticoagulation compared with UFH in persons with acute VTE and have gained popularity in the setting of VTE in cancer. LMWHs have the advantage of less non-specific protein binding, subcutaneous weight-based dosing without the need for monitoring in most cases, and probably less heparin-induced thrombocytopenia. Recent trials have demonstrated efficacy superiority of select LMWHs in place of oral warfarin for long-term anticoagulation in the cancer patient. The potential for anti-tumor effects and a survival advantage associated with select classes of anticoagulant agents is actively being investigated.

Upper-extremity deep vein thrombosis: a prospective registry of 592 patients

BACKGROUND

Upper-extremity deep vein thrombosis (UEDVT) occurs spontaneously or sometimes develops as a complication of pacemaker use, long-term use of a central venous catheter (CVC), or cancer.

METHODS AND RESULTS

To improve our understanding of UEDVT, we compared the demographics, symptoms, risk factors, prophylaxis, and initial management of 324 (6%) patients with central venous catheter (CVC)-associated UEDVT, 268 (5%) patients with non-CVC-associated UEDVT, and 4796 (89%) patients with lower-extremity DVT from a prospective US multicenter DVT registry. The non-CVC-associated UEDVT patients were younger (59.2+/-18.2 versus 64.2+/-16.9 years old; P<0.0001), less often white (65% versus 73%; P<0.01), leaner (body mass index [BMI] 26.8+/-7.1 versus 28.5+/-7.3 kg/m2; P<0.001), and more likely to smoke (19% versus 13%; P=0.02) than the lower-extremity DVT patients. By way of propensity analysis and multivariable logistic regression analysis, we determined that an indwelling CVC was the strongest independent predictor of UEDVT (odds ratio [OR], 7.3; 95% confidence interval [CI], 5.8 to 9.2). An age of <67 years, a BMI of <25 kg/m2, and hospitalization were the independent predictors of non-CVC-associated UEDVT. Most (68%) UEDVT patients were evaluated while they were inpatients. Only 20% of the 378 UEDVT patients who did not have an obvious contraindication to anticoagulation received prophylaxis at the time of diagnosis.

CONCLUSIONS

UEDVT risk factors differ from the conventional risk factors for lower-extremity DVT. Our findings identify deficiencies in our current understanding and the prophylaxis of UEDVT and generate hypotheses for future research efforts.

Totally implantable femoral vein catheters in cancer patients

INTRODUCTION

Totally implantable devices are increasingly being utilized for chemotherapy treatment of oncological patients. When it is impossible to implant the reservoir on the anterior wall of the thorax, or when there is an obstruction of the superior vena cava system, alternative access routes must be sought. Of these, the femoral vein is the most utilized. Few studies have been performed to analyse the results obtained from the implantation and utilization of such catheters in the femoral vein. The goal of this work was to prospectively study the results obtained from the implantation of 20 TIC in femoral veins in a large-sized cancer hospital with its own dedicated vascular clinical team.

MATERIAL AND METHODS

Twenty femoral TIC were inserted in 20 patients out of a group of 560 cancer patients submitted to TIC implantation for chemotherapy. Evaluations were made of the early and late-stage complications and patient evolution until removal of the device, death or the end of the treatment.

RESULTS

The prospective analysis showed a mean duration of 215 days for the catheters. There were 16 patients with no complications. There were no early complications. Among the late complications, three were infections, representing 0.69/1000 days of catheter use, and one was a deep vein thrombosis (0.23/1000 days of catheter use). One catheter was removed due to primary bacteremia and one due to subcutaneous pocket infection. Fourteen patients died while the catheter was functioning and four patients are still making use of the catheter.

CONCLUSION

The low rate of complications implying catheter loss in this study confirms the safety and convenience of the use of femoral TIC in patients who cannot be submitted to implantation in the superior vena cava system.

Totally implantable venous catheters for chemotherapy: experience in 500 patients

CONTEXT

Totally implantable devices are increasingly being utilized for chemotherapy treatment of oncological patients, although few studies have been done in our environment to analyze the results obtained from the implantation and utilization of such catheters.

OBJECTIVE

To study the results obtained from the implantation of totally implantable catheters in patients submitted to chemotherapy.

TYPE OF STUDY

Prospective.

SETTING

Hospital do Cancer A.C. Camargo, Sao Paulo, Brazil.

METHODS

519 totally implantable catheters were placed in 500 patients submitted to chemotherapy, with preference for the use of the right external jugular vein. Evaluations were made of the early and late-stage complications and patient evolution until removal of the device, death or the end of the treatment.

RESULTS

The prospective analysis showed an average duration of 353 days for the catheters. There were 427 (82.2%) catheters with no complications. Among the early complications observed, there were 15 pathway hematomas, 8 cases of thrombophlebitis of the distal stump of the external jugular vein and one case of pocket infection. Among the late-stage complications observed, there were 43 infectious complications (0.23/1000 days of catheter use), 11 obstructions (0.06/1000 days of catheter use) and 14 cases of deep vein thrombosis (0.07/1000 days of catheter use). Removal of 101 catheters was performed: 35 due to complications and 66 upon terminating the treatment. A total of 240 patients died while the catheter was functioning and 178 patients are still making use of the catheter.

CONCLUSION

The low rate of complications obtained in this study confirms the safety and convenience of the use of totally implantable accesses in patients undergoing prolonged chemotherapy regimes.

Central venous catheters: choosing the most appropriate access route

Intravenous therapy and care is a complex and intricate area of practice, which is being subsumed into the core role of registered nurses. As more patients become recipients of a vascular access device (VAD), particularly those requiring intermediate to long-term central venous access, it is important to ensure that not only the device but also the most appropriate vein meets their clinical physiological and psychological needs. There is much research and literature on the insertion and care of central venous catheters (CVCs) as well as the detection and treatment of complications. However, apart from a few small studies comparing the performance of devices placed either in the subclavian or jugular veins, there is little to guide doctors or nurses as to which vein is preferable, if secondary complications are to be avoided. This article will describe a number of primary and secondary complications associated with both the subclavian and internal jugular veins and how these can be minimized by selecting the most appropriate vessel. The article concludes with the author's suggestions for correct patient assessment in order that the correct vein is utilized.

Thrombotic Complications of Central Venous Catheters in Cancer Patients

Central venous catheters (CVCs), such as the tunneled catheters and the totally implanted ports, play a major role in general medicine and oncology. Aside from the complications (pneumothorax, hemorrhage) associated with their initial insertion, all of these CVCs are associated with the long-term risks of infection and thrombosis. Despite routine flushing with heparin or saline, 41% of CVCs result in thrombosis of the blood vessel, and this markedly increases the risk of infection. Only one-third of these clots are symptomatic. Within days of insertion, almost all CVCs are coated with a fibrin sheath, and within 30 days, most CVC-related thrombi arise. Aside from reducing the function of the catheter, these CVC-related thrombi can cause postphlebitic syndrome in 15%-30% of cases and pulmonary embolism in 11% (only half of which are symptomatic). Risk factors for CVC thrombosis include the type of malignancy, type of chemotherapy, type of CVC, and locations of insertion site and catheter tip, but not inherited thrombophilic risk factors. Efforts to reduce CVC thrombosis with systemic prophylactic anticoagulation with low-molecular-weight heparin have failed. Low-dose warfarin prophylaxis remains controversial; all studies are flawed, with older studies, but not newer ones, showing benefit. Currently, less than 10% of patients with CVCs receive any systemic prophylaxis. Although its general use cannot be recommended, low-dose warfarin may be a low-risk treatment in patients with good nutrition and adequate hepatic function. Clearly, additional studies are required to substantiate the prophylactic use of low-dose warfarin. Newer anticoagulant treatments, such as pentasaccharide and direct thrombin inhibitors, need to be explored to address this major medical problem.

Venous thromboembolism associated with long-term use of central venous catheters in cancer patients

Long-term central venous catheters (CVCs) have considerably improved the management of cancer patients because they facilitate chemotherapy, transfusions, parenteral nutrition, and blood sampling. However, the use of long-term CVCs, especially for chemotherapy, has been associated with the occurrence of upper-limb deep venous thrombosis (UL-DVT). The incidence of clinically overt UL-DVT related to CVCs has been reported to vary between 0.3% and 28.3%. The incidence of CVC-related UL-DVT screened by venography reportedly varies between 27% and 66%. The incidence of clinically overt pulmonary embolism (PE) in patients with CVC-related UL-DVT ranges from 15% to 25%, but an autopsy-proven PE rate of up to 50% has been reported. Vessel injury caused by the procedure of CVC insertion, venous stasis caused by the indwelling CVC, and cancer-related hypercoagulability are the main pathogenetic factors for CVC-related venous thromboembolism (VTE). Several studies have assessed the benefit of the prophylaxis of UL-DVT after CVC insertion in cancer patients. According to the results of these studies, prophylaxis with low molecular weight heparin or a low fixed dose of warfarin has been recently proposed. However, the limitations of the experimental design of the prophylactic studies do not allow definitive recommendations. The recommended therapy for UL-DVT associated with CVC is based on anticoagulant therapy with or without catheter removal. This review focuses on the epidemiology, pathogenesis, diagnosis, prevention, and treatment of VTE in cancer patients with long-term CVC.

Central line thrombosis in patients with cancer

Central venous catheters are used frequently to care for patients with cancer and often serve as long-term venous access. Catheter-related central venous thrombosis is a serious and common complication in these patients. The incidence of this event ranges from 2 to 40%. Potential risk factors are catheter position, size of the catheter, and perhaps site of insertion. The diagnosis of catheter-associated deep venous thrombosis may be difficult. Doppler ultrasound has a lower accuracy in this setting than it does in symptomatic lower extremity venous thrombosis. No clinical management studies have validated the practice of withholding anticoagulant therapy in patients with a negative Doppler ultrasound. The practice of prophylaxis with low-dose warfarin or low-molecular-weight heparin has been recommended, although results from recent studies have called this into question. Larger, prospective, randomized trials with a uniform population of patients or stratification of risk factors will be essential to address this issue further.

Central venous line-related thrombosis in children: association with central venous line location and insertion technique

Venous thromboembolic events (VTEs) in children are associated with central venous lines (CVLs). The study objective was to assess whether CVL location and insertion technique are associated with the incidence of VTE in children. We hypothesized that VTE would be more frequent with (1). CVL location on the left body side, (2). CVL location in the subclavian vein rather than the jugular vein, and (3). CVL insertion by percutaneous technique rather than venous cut-down. This was a prospective, multicenter cohort study in children with acute lymphoblastic leukemia who had a CVL placed in the upper venous system during induction chemotherapy. Characteristics of CVL were documented prospectively. All children had outcome assessment for VTE by objective radiographic tests, including bilateral venography, ultrasound, echocardiography, and cranial magnetic resonance imaging. Among 85 children, 29 (34%) had VTE; 28 VTEs appeared in the upper venous system, and 1 was sinovenous thrombosis. Left-sided CVL (odds ratio [OR], 2.5; 95% confidence interval, 1.0-6.4; P =.048), subclavian CVL (OR, 3.1; 95% CI, 1.2-8.5; P =.025), and percutaneous CVL insertion (OR, 3.5; 95% CI, 1.3-9.2; P =.011) were associated with an increased incidence of VTE. Interaction occurred between CVL vein location and insertion technique. Subclavian vein CVL inserted percutaneously had an increased incidence (54%) of VTE compared with any other combination (P =.07). For CVL in the upper venous system, CVL placement on the right side and in the jugular vein may reduce the risk for CVL-related VTE. If subclavian vein placement is necessary, CVL insertion by venous cut-down appears preferable over percutaneous insertion.

Minidose warfarin prophylaxis for catheter-associated thrombosis in cancer patients: can it be safely associated with fluorouracil-based chemotherapy?

PURPOSE

The use of prophylactic low-dose oral warfarin in cancer patients with a central venous catheter (CVC) in place has an established role in the prevention of thrombotic complications and is associated with a low hemorrhagic risk. Despite the literature indicating an adverse interaction between warfarin and fluorouracil (FU), the frequency of this interaction and whether it occurs when minidose warfarin is used is unknown. We analyzed the incidence of alterations in the International Normalized Ratio (INR) and bleeding in cancer patients given minidose warfarin during treatment with continuous-infusion FU-based regimens.

PATIENTS AND METHODS

Between July 1999 and August 2001, 95 cancer patients were evaluated. Forty-one patients (43%) had liver metastases. Seventy-nine patients (83%) had a Groshong CVC (Bard Access System, Salt Lake City, UT), and 16 (17%) had a Port-a-Cath device (Bard Access System). All patients received oral warfarin at a dose of 1 mg/daily as prophylaxis beginning the day after the catheter was positioned. An INR of more than 1.5 was considered significantly elevated.

RESULTS

INR elevation occurred in 31 patients (33%), with 18 patients (19%) having an INR more than 3.0. Twelve (39%) of the 31 patients had liver metastases. Bleeding was observed in eight patients (8%); seven of these patients had elevated INR levels. We observed INR elevations in 12 of 21 patients treated with a FU, folinic acid, and oxaliplatin (FOLFOX) regimen, 11 of 40 treated with a de Gramont regimen (FU and folinic acid), and five of 19 treated with a FU, folinic acid, and irinotecan (FOLFIRI) regimen.

CONCLUSION

A high incidence of INR abnormalities was observed in our cohort of patients, especially those treated with FOLFOX regimen. Clinicians should be aware of this interaction and should regularly monitor the prothrombin time in patients receiving warfarin and FU.

Treatment of venous thromboembolism in cancer patients

The management of deep vein thrombosis (DVT) and pulmonary embolism (PE) in patients with cancer can be a clinical dilemma. Comorbid conditions, warfarin failure, difficult venous access, and a high bleeding risk are some of the factors that often complicate anticoagulant therapy in these patients. In addition, the use of central venous access devices is increasing but the optimal treatment of catheter-related thrombosis remains controversial. Unfractionated heparin (UFH) is the traditional standard for the initial treatment of venous thromboembolism (VTE) but low molecular weight heparins (LMWHs) have been shown to be equally safe and effective in hemodynamically stable patients. For long-term treatment or secondary prophylaxis, vitamin K antagonists remain the mainstay treatment. However, the inconvenience and narrow therapeutic window of oral anticoagulants make extended therapy unattractive and problematic. As a result, LMWHs are being evaluated as an alternative for long-term therapy. New antithrombotic agents are being tested in clinical trials and may have the potential to replace conventional treatment. The role of inferior vena cava filters in cancer patients remains ill defined but these devices remain the treatment of choice in patients with contraindications for anticoagulant therapy.

Complications of long-term home total parenteral nutrition: their identification, prevention and treatment

The purpose of this review is to describe the most common complications of home total parenteral nutrition, their identification, treatment and prevention. Data sources were manuscripts and abstracts published in the English literature since 1968. Studies were selected for summarization in this review on the basis of clinical relevance to the practicing clinician. Home total parenteral nutrition is a relatively safe, life-saving method for nutrient delivery in patients with compromised gastrointestinal function. However, numerous complications, with associated morbidity and mortality, involving the delivery system and the gastrointestinal, renal, and skeletal systems may develop. Catheter-related complications are often preventable and treatable when they occur, although renal and bone abnormalities have elusive etiologies.

Tunneled infusion catheters: increased incidence of symptomatic venous thrombosis after subclavian versus internal jugular venous access

PURPOSE

To compare the incidence of symptomatic venous thrombosis after tunneled infusion catheter placement via the internal jugular vein (IJV) versus the subclavian vein (SCV).

MATERIALS AND METHODS

A retrospective analysis was performed of 774 catheters placed. Only patients with complete follow-up were included, which yielded a population of 279 catheters in 238 patients (166 in the SCV, 113 in the IJV; total of 26,242 catheter days). All catheters were placed by interventional radiologists with ultrasonographic (in IJV) or venographic (in SCV) guidance.

RESULTS

Initial complications were limited to one pneumothorax in the SCV group and one episode of oversedation in the IJV group. There was no difference in infection rates between the two sites (SVC vs IJV: 0.25 vs 0.32 per 100 catheter days; P >.99). The mean dwell time was slightly longer for SCV catheters (103 days) than for IJV catheters (79 days) (P =.04). Venous thrombosis developed in 13% of patients (0.12 per 100 catheter days) with an SVC catheter placed as compared with in 3% (0.04 per 100 catheter days) with an IJV catheter (P =.018). This difference persisted after adjustment for catheter size and side of placement (P =.025). The mean time to thrombosis was 36 days for SCV catheters and 142 days for IJV catheters.

CONCLUSION

The IJV is the preferred site for tunneled infusion catheter placement because of the lower incidence of symptomatic venous thrombosis.

Resistance to Coccidioides immitis in mice after immunization with recombinant protein or a DNA vaccine of a proline-rich antigen

Two inbred strains of mice (BALB/c and C57BL/6) were vaccinated with either recombinant expression protein of a Coccidioides immitis spherule-derived proline-rich antigen (rPRA) in monophosphoryl lipid A-oil emulsion adjuvant or a DNA vaccine based on the same antigen. Four weeks after vaccination, mice were infected intraperitoneally with arthroconidia. By 2 weeks, groups of mice receiving saline or plasmids with no PRA insert exhibited significant weight loss, and quantitative CFUs in the lungs ranged from 5.9 to 6.4 log10. In contrast, groups of mice immunized with either rPRA or DNA vaccine had significantly smaller pulmonary fungal burdens, ranging from 3.0 to 4.5 log10 fewer CFUs. In vitro immunologic markers of lymphocyte proliferation and gamma interferon (IFN-gamma) release after splenocytes were stimulated with rPRA correlated with protection. Also, plasma concentrations of rPRA-specific total immunoglobulin G (IgG), IgG1, and IgG2a showed increases in vaccinated mice. These studies expand earlier work by demonstrating protection in mice which differ in H-2 background, by using an adjuvant that is potentially applicable to human use, and by achieving comparable protections with a DNA-based vaccine. Our in vitro results substantiate a Th1 response as evidenced by IFN-gamma release and increased IgG2a. However, IgG1 was also stimulated, suggesting some Th2 response as well. PRA is a promising vaccine candidate for prevention of coccidioidomycosis and warrants further investigation.

Regional thrombolysis with urokinase for central venous catheter-related thrombosis in patients undergoing high-dose chemotherapy with autologous blood stem cell rescue

Fifty-one of 300 patients undergoing high-dose chemotherapy with (n = 245) or without (n = 55) autologous stem cell rescue developed central venous catheter-related thrombosis diagnosed by Doppler sonography or contrast venography. Eighteen of these individuals underwent regional thrombolysis defined as the infusion of urokinase into a superficial vein of the ipsilateral upper extremity in a dose not sufficient to produce systemic fibrinolysis by laboratory criteria. Urokinase was administered at a dose of 75,000-150,000 U/hour for 24 to 96 hours and contrast venography was performed to assess response. All individuals had a partial or complete resolution of clinical signs and symptoms. Fifty percent of patients also achieved a partial radiographic response defined as clot lysis with irregular canalization of the vein. Therapeutic doses of heparin for 5 to 7 days and warfarin for at least 3 months were commenced at the conclusion of urokinase therapy. Twelve catheters were salvaged and utilized subsequently until no longer required. Six catheters were removed because of poor catheter function or rethrombosis. The median interval from diagnosis of the thrombus until extraction of the 12 salvaged catheters was 3 months (range 1-8 months). Only a single patient who developed gastrointestinal bleeding required discontinuation of urokinase. Regional thrombolysis is safe, easy to administer, effective in many instances, less costly than the doses of antifibrinolytic agents required to induce systemic fibrinolysis, and should be considered in patients receiving high-dose chemotherapy with autologous stem cell rescue who develop central venous catheter-related thrombosis.

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.

The timing and sequence of multiple device-related complications in patients with indwelling subcutaneous ports

BACKGROUND

Multiple complications associated with venous access ports are a common occurrence. In an effort to define patterns of sequential complications in our community, we undertook a prospective analysis of adult cancer patients in whom a subcutaneous port was inserted.

METHODS

One hundred nineteen consecutive adult cancer patients in whom a subcutaneous port was inserted were observed prospectively for the development of complications.

RESULTS

Complications were identified in 70 of the 91 evaluable patients, while sequential complications were identified in 35 patients (38%). In aggregate, 121 complications were identified. The ball-valve effect, the most frequently identified problem, was found to occur disproportionately as a primary complication (52 of 70 versus 26 of 51, P <0.02). In contrast, port-related venous thrombosis was identified most frequently as a subsequent complication (11 of 51 versus 4 of 70, P <0.02). The only identified risk factor for the development of port-related complications was the ball-valve effect, found to be associated with the subsequent development of port-related venous thrombosis (9 of 52 versus 2 of 69, P <0.02).

CONCLUSIONS

Multiple sequential complications of subcutaneous ports are common and occur in a rather predictable order. The occurrence of port-related venous thrombosis in patients with an earlier, relatively minor vascular complication (ball-valve effect) suggests a cause-effect relationship. Insight into complication sequencing may lead to improved strategies for prevention and therapy.