Prevention of recurrent thrombotic events in children with central venous catheter-associated venous thrombosis

Central venous catheters (CVC) are the most significant risk factor for pediatric venous thromboembolism (VTE). After an index CVC-associated VTE (CVC-VTE), the role of secondary prophylaxis for subsequent CVC placement is uncertain. Aims of this single-center retrospective study were to evaluate the efficacy of secondary prophylaxis for patients with a prior CVC-VTE and identify risk factors associated with recurrent VTE in patients less than 19 years with an index CVC-VTE between 2003 and 2013. Data collection included clinical and demographic factors, subsequent CVC placement, secondary prophylaxis strategy, recurrent VTE, and bleeding. Risk factors for recurrence and effectiveness of secondary prophylaxis were evaluated using survival and binomial models. Among 373 patients with an index CVC-VTE, 239 (64.1%) had subsequent CVC placement; 17.4% (65/ 373) of patients had recurrent VTE, of which 90.8% (59/65) were CVC-associated. On multivariable survival analysis, each additional CVC (hazards ratio [HR] 12.00; 95% confidence interval [CI] 2.78-51.91), congenital heart disease (HR 3.70; 95% CI 1.97-6.95), and total parenteral nutrition dependence (HR 4.02; 95% CI 2.23-7.28) were associated with an increased hazard of recurrence. Full dose anticoagulation for secondary prophylaxis was associated with decreased odds of recurrent CVC-VTE (odds ratio [OR] 0.35; 95% CI 0.19-0.65) but not prophylactic dosing (OR 0.61; 95% CI 0.28-1.30). Only 1.3% of CVCs experienced major bleeding with prophylactic or full-dose anticoagulation. In summary, children with CVC-VTE are at increased risk for recurrent VTE. Secondary prophylaxis with full-dose anticoagulation was associated with a 65% reduction in odds of thrombotic events.