Implantable venous access devices (VADs) are used in sickle cell disease (SCD) for patients with poor venous access to facilitate chronic blood transfusions and management of acute complications. Children and adults with chronic illnesses have high rates of VAD-related complications including bloodstream infection and thrombosis. Patients with SCD may be at higher risk given the presence of functional asplenia and evidence of a hypercoaguable state. The objective of this study was to define the frequency of VAD related bloodstream infections and thrombosis in adults and children with SCD.
We performed a single institution retrospective review of VAD placement in patients with SCD. Subjects were identified through the sickle cell clinic database and the Hospital Information System. Subjects were included if they had SCD, VAD placement between December 1, 1998 to December 1, 2009 and had completed at least 12 months of follow-up. VAD-related bloodstream infection was defined by positive blood culture and VAD-related thrombosis (deep vein thrombosis, superior vena cava syndrome, and pulmonary embolism without lower extremity thrombosis) was defined by imaging. Comparisons were made between pediatric and adult sickle cell patients using Student's t-test for continuous variables and Fisher's exact test was used to compare categorical variables; p<0.05 was considered significant.
Of the greater than 800 sickle cell patients followed at our Comprehensive Sickle Cell Center, 32 subjects were eligible for inclusion (median age 20 years, range 1–59). There were 81 VAD placed (median 2.6 VAD per patient, range 1–7) with a total of 49268 catheter days (median 608, range 323–3999). The mean catheter lifespan in adults (1798 days ± 266) was significantly higher than pediatric patients (971 ± 328, p=0.039). There were a total of 66 VAD-related bloodstream infections (1.34 infections per 1000 catheter days) occurring in 17 of 32 (53%) subjects. Although not statistically significant, children had fewer VAD-related bloodstream infections (3 of 10; 30%) compared to adults (14 of 22; 64%, p=0.08). There were 24 catheter-related thromboses (0.49 thromboses per 1000 catheter days) occurring in 10 of 32 (41%) of subjects. Children also had fewer VAD-related thrombosis (1 of 10; 10%) compared to adults (9 of 22; 40%, p=0.08). The overall rates of infection and thrombosis per 1000 catheter days were not significantly different between adult and pediatric patients.
In summary, we report a long lifespan and low rate of infection in the subjects who had VADs during the study period. Most concerning was a high proportion of adults with catheter-related thrombosis, which adds the burden of anticoagulation to patient management and put patients at risk for post-thrombotic syndrome. Potential lifespan of VADs, risk of bloodstream infection and thrombosis as well as its long-term consequences should be discussed with patients and families considering VAD placement.
No relevant conflicts of interest to declare.
Asterisk with author names denotes non-ASH members.