Central Venous Catheter Thrombosis Research Articles

Gene Polymorphism Association Studies in Dialysis: Vascular Access

Complications of the vascular access site for hemodialysis are a major cause of morbidity, suboptimal dialysis, and hospitalization. Vascular access for dialysis that is achieved by central venous catheters is associated with complications such as infection and thrombosis. Arteriovenous fistulas and grafts are also at risk for infectious complications. Further, proliferation of the venous wall with secondary thrombosis is a common pathophysiological process that leads to vascular access dysfunction. Genetic polymorphisms that contribute to vascular access failure are found among factors of the coagulation cascade, and host mediators that induce endothelial dysfunction as well as vessel wall proliferation. The two most common mutations of coagulation factors seem to influence the risk of central venous catheter and fistula thrombosis. Indeed, both the single nucleotide polymorphism of the factor V gene at amino acid position 506 (factor V Leiden mutation) and the prothrombin 20210 polymorphism have been associated with thrombotic complications of the vascular access. Among the endothelium-directed factors, a polymorphism of the methylene tetrahydrofolate reductase gene coding for an enzyme that degrades the endothelium toxic product homocysteine, has been associated with fistula failure. While the angiotensin converting enzyme polymorphism does not seem to be associated with vascular access complications, polymorphisms of the profibrogenic cytokine transforming growth factor-beta1 are associated with the prognosis of native arteriovenous fistulae. The role of pro- and anti-inflammatory cytokine gene polymorphisms as prognostic factors for vascular access is yet to be clearly defined.

High Incidence of Venous Thromboembolism in Patients with Lymphoma Receiving Chemotherapy: Assessment of Risk Factors.

Background: Venous thromboembolism (VTE) is a significant cause of cancer morbidity and mortality. Lymphoma patients (pts) are at increased risk of VTE, however, the exact incidence and risk factors are unknown.Methods: Of the 1050 newly referred Lymphoma pts to MDACC in 2003 identified, medical records (MR) of 538 consecutive pts were reviewed for demographics, tumor histology, staging, laboratory values, type of chemotherapy (CT) regimens, risk factors for VTE, incidence of VTE and management over a follow up of 2 years.Results: 207 out of 538 pts received at least one cycle of CT at MDACC (total CT cycles 1125). The median age was 56 years (range 17–82); there were 81 females and 126 males. Majority of pts (61.8%) were newly diagnosed and the most common histologies were Large Cell Lymphoma (31.88%), followed by Hodgkin's Disease (16.9%) and Follicular Lymphoma (14.98%). Thirteen out of 207 (6.28%) pts had history of VTE prior to CT and 37 (17.9 %) pts out of 207 had 41 new episodes of VTE; 29 Deep Vein Thrombosis (DVT) (12 upper and 12 lower extremity) and 12 Pulmonary Embolism (PE); 2 pts had both DVT and PE. All VTE episodes were confirmed by imaging except in 3 pts. The mean baseline hemoglobin (Hb) in VTE pts was 12.8 g/dL. The median cycle number for VTE occurrence was cycle 3 with 24/37 (64.86%) pts experiencing VTE by cycle 3 and 6/37 (16.2%) pts had VTE in cycle 1. Two out of the 37 (5.4%) pts had recurrent VTE. Among those with new VTE, 31/37 (83.78%) pts were of age greater than 40, 25/37 (67.56%) pts had BMI > 25, 32/37 (86.4%) pts had aggressive or highly aggressive histology and 29/37 (78.37%) pts had stage 3 or 4 disease. Twenty-three out of 31 (74.2%) pts had received erythropoietin before or during the cycle of VTE. Fourteen of 207 (6.79%) pts were on thromboprophylaxis before the chemotherapy. Only 1 of these 14 pts experienced VTE, approximately 2 months after the discontinuation of prophylaxis. Central venous catheter (CVC) thrombosis occurred in 6/174 (3.44%) patients with CVC. The most common systemic treatment for VTE was Enoxaparin (12/33). By multivariate logistic regression analysis of many of the previously described risk factors and other variables, Doxorubicin and/or Methotrexate based CT regimen was found to be a significant independent risk factor for VTE (OR 5.58, 95%CI 1.62 to 19.13. p = 0.0062).Conclusion: VTE is a frequent and underestimated complication in Lymphoma pts. These findings underscore the importance of prospective clinical trials of anticoagulation prophylaxis in the high risk patients receiving CT.

Incidence, Risk Factors, and Outcomes of Catheter-Related Thrombosis in Adult Patients With Cancer

Thrombosis of long-term central venous catheters (CVC) is a serious complication that causes morbidity and interrupts the infusion of chemotherapy, intravenous medication, and blood products. We performed a prospective study to examine the incidence, risk factors, and long-term complications of symptomatic catheter-related thrombosis (CRT) in adults with cancer. Consecutive patients with cancer, undergoing insertion of a CVC, were enrolled and prospectively followed while their catheter remained in place plus 4 subsequent weeks or a maximum of 52 weeks, whichever came first. Patients with symptomatic CRT were followed for an additional 52 weeks from the date of CRT diagnosis. The end points were symptomatic CRT, symptomatic pulmonary embolism (PE), postphlebitic syndrome, and catheter life span. Over 76,713 patient-days of follow-up, 19 of 444 patients (4.3%) had symptomatic CRT in 19 of 500 catheters (0.3 per 1,000 catheter-days). The median time to CRT was 30 days and the median catheter life span was 88 days. Significant baseline risk factors for CRT were: more than one insertion attempt (odds ratio [OR] = 5.5; 95% CI, 1.2 to 24.6; P = .03); ovarian cancer (OR = 4.8; 95% CI, 1.5 to 15.1; P = .01); and previous CVC insertion (OR = 3.8; 95% CI, 1.4 to 10.4; P = .01). Nine of the 19 CRT patients were treated with anticoagulants alone, eight patients were treated with anticoagulants and catheter removal, while two patients did not receive anticoagulation. None had recurrent CRT or symptomatic PE. Postphlebitic symptoms were infrequent. In adults with cancer, the incidence of symptomatic CRT is low and long-term complications are uncommon.

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.

Is antithrombotic prophylaxis required in cancer patients with central venous catheters? Yes for special patient groups.

Is antithrombotic prophylaxis required in cancer patients with central venous catheters? Yes for special patient groups.

Central venous catheter thrombosis as a cause of SVC obstruction and cardiac tamponade in a patient with Diamond-Blackfan anemia and iron overload

Cardiac tamponade is an infrequent but potentially lethal complication related to use of central venous catheters (CVC). We present the case of a 16-year-old female with Diamond-Blackfan anemia (DBA) who developed pericardial tamponade secondary to superior venous caval obstruction caused by CVC thrombosis. The patient presented 3 months after line placement with vomiting, abdominal pain, and cardiomegaly on chest X-ray (CXR). Her condition quickly decompensated with cardiac arrest and subsequent death despite immediate pericardiocentesis. As a result of this case, our center has developed a protocol for the management of CVC problems as a means of facilitating rapid recognition of central line clots.

Central Venous Catheter Thrombosis Complicated by Paradoxical Embolism in a Patient With Diabetic Ketoacidosis and Respiratory Failure

Paradoxical embolus should be suspected in young patients with cerebrovascular events who do not have any vascular risk factors. There is significant controversy as to how best to treat his phenomenon. A case observation in a tertiary care center. A 46-year-old was admitted to the intensive care unit (ICU) for unresponsiveness secondary to diabetic ketoacidosis and acute respiratory distress syndrome. He was intubated, and central access was obtained through the right internal jugular vein. Initial computed tomography (CT) scan of his brain was unremarkable. Four days later, he suddenly became increasingly unresponsive. Repeat CT scan of the brain revealed large bilateral posterior infarcts. Transesophegeal echocardiogram revealed a patent foramen ovale (PFO), and Doppler ultrasound revealed a thrombus in the low right jugular vein. He was anticoagulated for 3 months with no intervention for his PFO. This case emphasizes the potential complications of the use of central lines in ICUs, particularly in patients with diabetic ketoacidosis in whom sluggish blood flow may predispose to a procoagulant state.

Is Thrombophilia a Risk Factor for Peripheral Vein Infusion Thrombophlebitis?.

Background and Objectives. Peripheral vein infusion thrombophlebitis (PVIT) is a common complication in hospitalized patients receiving peripheral intravenous (IV) therapy. Although catheter-related risk factors such as catheter material have been well elucidated, patient-related factors have received little attention, despite evidence that (1) individuals vary in biologic vulnerability to developing PVIT; (2) there is biological evidence that thrombus formation may play a role in the pathogenesis of PVIT; and (3) thrombophilic disorders have been linked to central venous catheter thrombosis. We conducted a nested case-control study to determine whether patients who developed PVIT were more likely to have thrombophilia than patients without PVIT.Methods. A cohort of consecutive, hospitalized patients with peripheral IV catheters was prospectively assembled from 8 wards in 2 large tertiary care hospitals and followed until PVIT developed, the catheter was removed for reasons other than PVIT, or the patient was transferred with catheter in place to a non-study ward. Recruitment to the cohort continued until 100 patients, who developed PVIT, were eligible for case enrolment. For each case, 2 control patients who had not developed PVIT and who were matched to cases on catheter duration (days) were identified. PVIT was defined as the presence of two or more of the following at the catheter site: pain, tenderness, erythema, swelling, purulence, or a palpable cord. Factor V Leiden and prothrombin G20210A mutations and homocysteine levels were measured. Homocysteine levels ≥ 15μmol/L were considered elevated. The association between PVIT and thrombophilia was tested using multivariate conditional logistic regression analysis to account for the matched design.Results. From the cohort of 6426 patients with catheters, there were 113 PVIT episodes (PVIT incidence of 4.4 per 1000 catheter-days) of which 100 cases were eligible and matched to 200 randomly chosen controls. There were no differences between cases and controls with regard to age, sex distribution, history of previous venous thromboembolism (VTE) or presence of active cancer. Cases were less likely than controls to be taking anticoagulant medication(s) (9% vs. 16%, respectively, OR=0.46; 95% confidence interval (CI) [0.19, 1.12]). One or more prior episodes of PVIT was reported by 18% of cases vs. 6% of controls (OR=3.0; 95% CI [1.4, 6.2]). Prothrombin G20210A or Factor V Leiden was detected in 6% of cases and 6% of controls. Hyperhomocysteinemia was present in 24% of cases vs. 22% of controls (OR=1.23; 95% CI [0.69, 2.19]). Multivariable conditional regression analyses adjusted for age, sex and anticoagulant use showed that prior PVIT was an independent predictor of PVIT (OR=2.8; 95% CI [1.3, 6.0]), but thrombophilia did not predict PVIT (OR=1.02; 95% CI [0.57, 1.84]).Conclusions. We did not find an association between PVIT and Factor V Leiden, prothrombin gene mutation, or hyperhomocysteinemia, although our results suggest an unidentified patient-specific predisposition to PVIT. The pathogenesis of PVIT appears to be different than that of central venous catheter thrombosis, since thrombophilia, cancer and prior VTE, which are known risk factors for central venous catheter thrombosis, were not significantly associated with PVIT in our study.

Increased Risk for Thromboembolism Associated with High Coagulation Factor VIII (F VIII) Levels in Patients with Malignant Lymphoma.

An increased annual incidence of thromboembolic events (TE) of up to 11% has been observed in patients with solid tumors, whereas there exists little data on TE in hematologic malignancies. A previous study found a 6,6% incidence of TE in patients with high grade Non Hodgkin's lymphoma (HG-NHL) mostly occuring during the first three months of therapy. Little is known about pathogenesis and risk factors in this patient group. We retrospectively evaluated the medical records of all patients with malignant lymphoma treated at our institution between 1991 and 2004. In a seperate effort laboratory analysis for detection of acquired and hereditary thrombophilia was performed at diagnosis and during treatment in 44 patients with various hematologic malignancies: HG-NHL (n = 22), Low grade- NHL (LG-NHL) (n = 7), Hodgkin's disease (HD) (n = 6), CNS-lymphoma (n = 1) and acute myeloid leukemia (AML) (n = 8). A total of 96 TE occurred in 80 of 1048 patients (7,6%) with malignant lymphoma: DVT (n = 51), pulmonary embolism (n = 19), central venous catheter thrombosis (n = 11), upper extremity thrombosis due to tumor compression (n = 9), central nervous system thrombosis (n = 3), arterial thrombosis (n = 2) and portal vein thrombosis (n = 1). 69 TE (72%) occurred during treatment, whereas 27 (28%) were diagnosed prior to (n = 16) (17%) or after completion of therapy (n = 11) (11%). 9 patients (9%) had comorbid solid tumors. In 12 patients (15%) results of thrombophilia screening were available and FVIII levels were high (> 150%) in 7 (58%). In the prospectively analyzed patient cohort 30 (68%) had high FVIII levels, 22 (50%) showing very high levels (> 180%). High FVIII was associated with high von Willebrand factor (vWF) and increased collagen binding activity, but not with elevated IL 6 or TNF-a. 4 patients (9%) had heterozygous factor V Leiden mutation, one had the G20210A mutation of the prothrombin gene. Fibrinolysis was normal in all patients as were protein C, S and AT-III. No anticardiolipin antibodies or lupus anticoagulants were detected. However only 2 patients (4,4%) in this cohort developed TE, one of whom also had heterozygous protein C resistance. Patients with malignant lymphoma are at substantial risk for TE, especially during treatment, thus prophylactic anticoagulation seems warranted. Our study shows sustained strikingly high factor VIII levels in patients with malignant lymphoma even months or years after a TE as well as in a prospectively analyzed, yet mostly asymptomatic cohort with lymphoma and acute leukemia. Infection as a cause of secondary F VIII elevation in these patients was ruled out by absence of fever and normal IL 6 and TNF-a. Increased FVIII activity (> 150%) has been recognized as an independent risk factor for TE, however the pathogenesis is unclear so far and high FVIII and vWF levels have previously also been found in Multiple Myeloma patients. Ongoing investigations will focus on the implication of these findings in the pathophysiology of hematologic disease.

Thrombosis prophylaxis in patient populations with a central venous catheter: a systematic review.

Central venous catheters (CVCs) are used in a wide variety of patients. Associated complications are thrombosis and infection. It is a matter of debate whether thromboprophylaxis is beneficial. We performed a systematic review of 3 different patient populations to render the available information in the literature more accessible to clinical practice: patients receiving parenteral nutrition (PN), patients with cancer, and patients admitted to intensive care units. Prophylaxis with heparin added to PN was found to give a nonsignificant reduction in the incidence of catheter-related thrombosis (pooled relative risk of randomized studies, 0.77; 95% confidence interval [CI], 0.11-5.48). In cancer patients, both low-dose warfarin and low-molecular-weight heparin significantly reduced the incidence of catheter-related thrombosis (relative risk of randomized studies, 0.25 [95% CI, 0.09-0.70] and 0.10 [95% CI, 0.01-0.71], respectively). So far, intensive care patients have hardly been studied with respect to thromboprophylaxis and the incidence of CVC thrombosis. Any effect of the type of catheter could not be established because of small numbers. There was no apparent increase in bleeding events with prophylactic anticoagulation in patients with CVCs. In the small number of patients studied, the addition of heparin to PN did not significantly decrease the risk of catheter-related thrombosis, whereas warfarin and dalteparin did decrease the thrombosis risk in cancer patients with CVCs. There is no apparent increase in bleeding events with prophylactic anticoagulants in patients with CVCs.

Preoperative concomitant radiotherapy and chemotherapy in ultrasound-staged T3 and T4 rectal cancer.

To analyze early results of a single institution's experience using neo-adjuvant chemoradiotherapy in locally advanced, ultrasound-staged rectal cancer. Since 1998, 67 consecutive patients (36 males and 31 females; mean age, 59.5) have received preoperative combined treatment for T3 or T4 rectal cancer. All patients were staged by endorectal ultrasound and computed tomography, and all had a pathology-demonstrated invasive adenocarcinoma of the rectum. Patients were treated preoperatively with concomitant radiochemotherapy: pelvic irradiation (50 Gy in 25 fractions) and protracted-venous-infusion 5-fluorouracil (225 mg/m2/d, 7 days per week). Patients were restaged within 4 weeks, then submitted to surgery within 6-7 weeks after the end of therapy. Adjuvant postoperative chemotherapy with 5-fluorouracil plus folinic acid--the "de Gramont" schedule--for 24 weeks was purposed to all patients. Radiotherapy was completed in all cases; only one patient required suspension of the treatment for grade 4 toxicity (diarrhea). Instead, chemotherapy was interrupted in 3 cases (2 for central venous catheter thrombosis and 1 for grade IV diarrhea). Sixty-six patients underwent surgical resection (1 patient died before surgical treatment). Radical surgery was performed in 94%, and 46% of the 26 patients with distal rectal cancer had a conservative sphincter-sparing surgery. A complete pathologic response (defined as no evidence of viable tumor cells) was obtained in 22%. At a median follow-up of 17 months, distant metastases have been observed in 10 patients, and 3 of them developed a local recurrence. The actuarial estimations of 4-year overall survival, disease-free survival, local and distant control are 79%, 61%, 94% and 61%, respectively. Preoperative chemoradiotherapy seems to be an effective and well-tolerated treatment with a low complication rate. The high percentage of down-staging and sphincter sparing, also in distal rectal cancer, shows the efficacy of the treatment, which could significantly influence the incidence of relapses and quality of life.

A retrospective experience of right atrial and superior vena caval thrombi diagnosed by transesophageal echocardiography

Central venous catheter (CVC) thrombosis and infection has become a frequent finding in immunosuppressed and chronically ill medical patients, particularly those with end-stage renal disease. Transeophageal echocardiography (TEE), as the only reliable noninvasive method of imaging the superior vena cava (SVC) is appreciated to be very useful in the evaluation of these lesions. We retrospectively review our findings of TEE for this purpose, with regard to frequency of positive findings, patient characteristics, and microbiologic findings from SVC and right atrial thrombi and vegetations associated with CVCs. (J Am Soc Echocardiogr 2002;15:76-79.)

Central Venous Catheter Thrombosis in Children with Cancer

Many children with cancer receive treatment through central venous catheters. One common complication is catheter-related thrombosis; as with adults,

Prevention and management of central venous catheter thrombosis.

Central venous catheters play an integral part in the treatment of patients with a variety of illnesses. Complications, although not common, do occur. However, the benefits of these devices far outweigh the risks. Thrombosis, one of the most common problems, can be divided into three distinct clinical entities. The prophylaxis, diagnosis, pathogenesis, and treatment of central venus catheter-related thromboses are critical in the treatment of patients requiring long-term venous access.

The Incidence of Percutaneous Central Venous Catheter (PCVC) Thrombosis in High Risk Neonates, and the Relationship of Thrombosis to the Occurrence and Persistence of Bacteremia 1420

Percutaneously inserted central venous catheters (PCVCs) are commonly used in high risk neonates, but may be complicated by the formation of thrombi in the central veins or right atrium, and/or the occurrence of foreign-body induced bacterial blood stream infection. The purpose of this study is to determine the incidence of PCVC-related, central vein and/or right atrial thrombosis in neonates. In addition, the study will assess the relationship of thrombus formation to the subsequent development of bacterial blood stream infection, and determine if the presence of a thrombus is associated with failure of antibiotic treatment to eradicate bacteremia. To date, 47 neonates(mean birth weight 1139.4 grams, mean gestational age 28.1 weeks) have been enrolled in the study. In all subjects, immediately post insertion, a blood culture was drawn from the PCVC. Within 72 hours of insertion, a baseline 2-D echocardiogram with color flow Doppler study was performed. Thereafter, while the catheter was in place, blood cultures were drawn and a follow-up 2-D echocardiogram/color flow Doppler study was done once weekly. If a positive blood culture was detected, two additional, quantitative blood cultures (one from the PCVC; one from a peripheral vein) were obtained prior to initiating antibiotic therapy, and a 2-D echocardiogram/color flow Doppler study was performed within 24 hours. Following initiation of antibiotic therapy, a single, daily blood culture was obtained from the PCVC or peripheral vein depending on access, until three consecutive, daily blood cultures showed no bacterial growth. The median duration of PCVC lines was 37 days. Four neonates(0.09%) had positive blood cultures, at a mean of 25.3 days post-insertion. Neonates had a median of 5 blood cultures performed. Only 1 neonate (0.02%) had evidence of thrombus formation on echocardiogram at 10 days post-insertion. Neonates are continuing to be enrolled in this study. Based on this preliminary data, it appears that, despite the fact that in our unit PCVC lines are not changed, PCVC-related bacteremia and thrombosis are rare complications.

Benefit of Heparin in Central Venous and Pulmonary Artery Catheters: A Meta-analysis of Randomized Controlled Trials

To evaluate the effect of heparin on thrombus formation and infection associated with use of central venous and pulmonary artery catheters. We used MEDLINE, EMBASE, citation review of relevant primary and review articles, personal files, and contact with expert informants. Fourteen randomized controlled trials evaluating prophylactic doses of heparin or heparin bonding were included. In duplicate, independently, we abstracted data on the population, intervention, outcome, and methodologic quality. Prophylactic heparin decreases catheter-related venous thrombosis (relative risk [RR], 0.43; 95% confidence interval [CI], 0.23, 0.78) and bacterial colonization (RR, 0.18; 95% CI, 0.06, 0.60) of central venous catheters and may decrease catheter-related bacteremia (RR, 0.26; 95% CI, 0.07, 1.03). Heparin bonding decreases the risk of pulmonary artery catheter clot formation within 24 h (RR, 0.08; 95% CI, 0.02, 0.37). Heparin administration effectively reduces thrombus formation and may reduce catheter-related infections in patients who have central venous and pulmonary artery catheters in place. Cost-effectiveness comparisons of unfractionated heparin, low molecular weight heparin, and warfarin are needed.

Anticoagulation with warfarin in infants and children.

To provide a comprehensive review of warfarin use in infants and children, including recommendations for appropriate dosage and monitoring parameters. A MEDLINE search (1966-1995) was used to identify pertinent English-language articles in the medical literature. The key search term was warfarin. Additional material was obtained from references cited in articles retrieved through MEDLINE. All articles involving children younger than 18 years were evaluated. In addition, articles on the pharmacokinetics and pharmacodynamics in adults, adverse effects, and drug interactions were included. Material selected for review included clinical trials, case reports, and surveys of practice. Warfarin has been used as prophylactic therapy in children with prosthetic cardiac valves as well as for prevention of thromboembolic complications associated with autoimmune disorders and protein C or protein S deficiency. Warfarin also has been used to prevent embolization in children with deep-vein thrombosis or clots in central venous catheters. According to the literature, an initial dosage of 0.1 mg/kg/d should provide anticoagulation without significant adverse effects. As in adults, dosing should be adjusted to achieve a target international normalized ratio (INR). Although the target range in children is not well established, INR values of 1.5-3 are recommended for most patients. Higher values have been used in children with prosthetic cardiac valves and hereditary clotting disorders. Due to its infrequent use, there is limited information on the effects of warfarin in children. Basic guidelines for initiating and monitoring warfarin were developed by using data gathered from clinical trials, retrospective reviews, case series, and surveys of practice.

Extensive thrombosis of the caval venous system after central venous catheters in severely burned patients

Central venous thrombosis is a rare but extremely dangerous complication following central venous catheter placement. Two cases of massive central venous thrombosis in severely burned patients are reported. The clinical course, diagnostic problems and treatment options are described and discussed. From these cases we conclude that central venous catheter thrombosis should be included early in the differential diagnosis of trunk and extremity oedema in patients with indwelling central venous catheters and that thrombolytic therapy is safe and effective even in the severely burned patient.

230 Patient years of experience with home long-term parenteral nutrition in childhood: Natural history and life of central venous catheters

The records of 27 pediatric patients who required parenteral nutrition (PN) for 5 to 14.5 years (mean ± SD, 8.5 ± 3.8) were analyzed to determine the frequency of complications with their central venous catheters (CVC). This represents a 230 patient-year experience. Patients with short bowel syndrome and chronic intestinal pseudoobstruction syndrome (CIPS) accounted for all but two of the patients. Unsuccessful medical management of the exit site or CVC infection was responsible for removal of 62% of the 123 CVCs. Ninety-five episodes of line infection occurred in 24 patients. Fifty (52%) were successfully treated without catheter removal. The organisms responsible for catheter removal were fungal (14), mycobacterium species (5), gram-positive cocci (22), or gramnegative bacilli (19). The CVCs were infected an average of once every 884 days. The life of the second CVC (23.5 ± 17.9 months) was significantly longer than that of the first ( P < .05). Clotting of the CVC with unsuccessful lysis of the clot was responsible for removal of 24%, and breakage or unsuccessful repair was responsible for 14%. In no patient were all possible venous sites for CVC placement exhausted. Patients with CIPS had substantially fewer catheter complications ( P < .05) than did those with short bowel syndrome. In conclusion, CVCs can “survive” without major complications for more than a decade. Numerous factors contribute to the increased rate of CVC survival over time, including improvement in PN self-care with greater experience, improvement in teaching, regular follow-up of patients, better management of infection, and better ability to treat CVC thrombosis or breakage.

Upper Extremity Deep Venous Thrombosis: Underdiagnosed and Potentially Lethal

The significance of upper extremity deep venous thrombosis (DVT) has been minimized in comparison to iliofemoral thrombosis, likely due to the erroneous belief that subsequent pulmonary thromboembolism is rare. The possibility of pulmonary thromboembolism originating in the upper extremity veins must now be seriously considered with catheters and medical instrumentation being performed more commonly in accessing the central venous system. It has been incorrectly assumed that the risk of pulmonary embolism was low due to the abundant collateral flow, and thus lack of stasis around an upper extremity even with venous occlusion. However, several studies, including a recent prospective trial, concluded that pulmonary embolism is not a rare complication in upper extremity DVT. Significantly, when comparing all sources of secondary upper extremity DVT, catheter-related upper extremity DVT is at greatest risk of subsequent pulmonary thromboembolism. We present an illustrative case documenting extensive pulmonary embolization that occurred following insertion of a central venous catheter and subsequent thrombosis of the right subclavian and innominate veins. With absolute contraindications to thrombolytic and anticoagulation therapy, prevention of further embolization was achieved by percutaneous insertion of a superior vena cava filter.