Central line associated bloodstream infections (CLABSI) result in significant morbidity and mortality, particularly in patients undergoing hematopoietic cell transplantation (HCT). HCT patients are at high risk for CLABSI due to multiple factors, including prolonged immune suppression and the need for long-term central venous access. The investigators want to assess the feasibility of the use of a parafilm central line barrier (parafilm) as standard of care in pediatric HCT patients. The investigators will also assess the effectiveness of the parafilm to reduce the incidence of CLABSI in these patients.