Deep Venous Thrombosis Screening of Hemophilia Patients with Central Venous Catheters.
Authors: Cost Carrye R. , Spencer Kim L. , Buchanan George R. , Journeycake Janna M. 
Published: April 2020

Abstract
Introduction: Central venous catheters (CVC) are employed to manage patients with severe bleeding disorders. However, up to 50% of these children may develop CVC-related deep vein thrombosis (CVC-DVT). Due to the high risk of CVC-DVT, in 2001 we instituted a DVT screening program consisting of performing contrast venograms and Doppler sonograms every two years after CVC insertion and regular assessment for signs or symptoms of post-thrombotic syndrome (PTS). Identification of early vascular changes prompted transitioning of patients to peripheral vein (PV) access within the following 12 months. We now report the outcome of this screening program.
Methods: We reviewed all patients with inherited bleeding disorders who had CVCs placed during 2000–08. Data collected included CVC type, location, duration, associated complications, and imaging results. Examination findings of prominent chest wall veins and arm circumference discrepancies were also recorded. We evaluated the time to transition to PV infusions.
Results: Thirty-six patients were studied, of whom 28 had Factor VIII deficiency, 6 Factor IX deficiency, and 2 severe von Willebrand disease. Thirty catheters were placed for prophylaxis and 7 for immune tolerance induction. One patient had 2 lines placed. Median age at line placement was 25 months. Catheters were inserted into the subclavian (n=15), external jugular (n=16), internal jugular (n=3), or facial vein (n=1); the site of 2 catheters is unknown. CVCs were in place a median of 41.3 ± 22.8 months. In 27 patients, the first venogram was performed at a median time of 25.5 months after placement. Of the other 9 patients (10 catheters), 5 catheters were in place ≤ 24 months, 1 CVC was removed without imaging, 2 patients transferred to other programs, 1 CVC was removed for infection within one month after placement, and 1 child died from sepsis with CVC in place (Haemophilia2006; 12: 183–6). Thirteen patients (36%) had evidence on venogram of DVT (defined as: 1) thrombosis, 2) stenosis, 3) post-stenotic dilation, or 4) multiple visible collaterals). Ten abnormalities were detected on first venogram and 3 on the second. None had an abnormal sonogram. Of the patients with abnormal venograms, 6 CVCs were in the subclavian and 7 in the external jugular vein. Median time from insertion to DVT identification was 26 ± 19.7 months. There was no difference in CVC duration between patients with and without abnormal venogram results. Seven CVCs were removed in patients with positive venograms. Median time between the abnormal venogram result and CVC removal was 10 months. Delay in removal of CVC was secondary to difficult peripheral access or parental resistance. Nine (69%) patients with CVC-DVT had dilated chest wall veins and/or ipsilateral arm swelling (conventional signs of PTS). Excluding symptomatic joint disease, no patient complained of arm pain or dysfunction.
Conclusion: Early screening identified a CVC-DVT incidence of 28% within 2 years and 36% within 4 years. Successful transition to PV infusion is usually possible within a year after vascular changes and before 5 years of CVC use. In addition, 69% of those with CVC-DVT had evidence of mild PTS. The late sequelae of CVC-DVT are unknown. Therefore, screening for DVT, early transition to PV, and long-term follow-up is essential when CVCs are used for children with inherited bleeding disorders.