Kids! We Need to CHAT about Clots and Central Lines.

Central venous catheters (CVCs) have been a crucial advance in caring for critically ill children, especially those with complex medical issues, cancer, or conditions requiring multiple intravenous medications or blood draws. Overall, CVC use and accessibility to CVCs have decreased the risk of medications associated with high risk of extravasation injuries (ie, chemotherapy) and increased accessibility for long-term total parental nutrition and apheresis procedures for numerous conditions [[1]Ares G. Hunter C.J. Central venous access in children: indications, devices, and risks.Curr Opin Pediatr. 2017; 29: 340-346Crossref PubMed Scopus (57) Google Scholar], thereby changing practice across specialties. While these devices have allowed for life-saving treatments, they also have serious complications, including catheter-associated bloodstream infections, malposition, catheter embolization, and venous thromboembolism (VTE) [2Jaffray J. Witmer C. O’Brien S.H. Diaz R. Ji L. Krava E. Young G. Peripherally inserted central catheters lead to a high risk of venous thromboembolism in children.Blood. 2020; 135: 220-226Crossref PubMed Scopus (47) Google Scholar, 3Pinon M. Bezzio S. Tovo P.A. Fagioli F. Farinasso L. Calabrese R. Marengo M. Giacchino M. A prospective 7-year survey on central venous catheter-related complications at a single pediatric hospital.Eur J Pediatr. 2009; 168: 1505-1512Crossref PubMed Scopus (60) Google Scholar, 4Fratino G. Molinari A.C. Parodi S. Longo S. Saracco P. Castagnola E. Haupt R. Central venous catheter-related complications in children with oncological/hematological diseases: an observational study of 418 devices.Ann Oncol. 2005; 16: 648-654Abstract Full Text Full Text PDF PubMed Scopus (174) Google Scholar, 5Carter J.H. Langley J.M. Kuhle S. Kirkland S. Risk factors for central venous catheter-associated bloodstream infection in pediatric patients: a cohort study.Infect Control Hosp Epidemiol. 2016; 37: 939-945Crossref PubMed Scopus (33) Google Scholar, 6Jamshidi R. Central venous catheters: indications, techniques, and complications.Semin Pediatr Surg. 2019; 28: 26-32Crossref Scopus (27) Google Scholar]. In this issue of the Journal of Thrombosis and Haemostasis, Jaffray et al. [[7]Jaffray J. Mosha M. Branchford B. Goldenberg N.A. Silvey M. Croteau S.E. Fargo J.H. Cooper J.D. Bakeer N. Stillings A. Krava E. Young G. Amankwah E.K. Evaluation of venous thromboembolism risk factors reveals subtype heterogenicity in children with central venous catheters: a multi-center study from the CHAT consortium.J Thromb Haemost. 2023; 21: 2441-2450Abstract Full Text Full Text PDF Scopus (1) Google Scholar] analyzed hospitalized children with a CVC, which accounts for up to 80% of hospital-acquired (HA) VTE cases [[6]Jamshidi R. Central venous catheters: indications, techniques, and complications.Semin Pediatr Surg. 2019; 28: 26-32Crossref Scopus (27) Google Scholar]. The study was part of the multicenter Children’s Hospital-Acquired Thrombosis (CHAT) Registry through the CHAT Consortium, a registry from 8 large US Children’s Hospitals [[8]Takemoto C.M. Sohi S. Desai K. Bharaj R. Khanna A. McFarland S. Klaus S. Irshad A. Goldenberg N.A. Strouse J.J. Streiff M.B. Hospital-associated venous thromboembolism in children: incidence and clinical characteristics.J Pediatr. 2014; 164: 332-338Abstract Full Text Full Text PDF PubMed Scopus (102) Google Scholar]. This is one of the largest cohorts of children with HA-VTE analyzed and sought to address some of the key knowledge gaps in pediatric VTE, including if certain catheter-related thrombosis (CRT) groups are at the highest risk; if the type of central catheter changes overall risk of thrombosis formation; and why some children with a CVC develop CRT, while others develop HA-VTE unrelated to the CVC. This study used a case-case design that compares the “cases of interest” (HA-VTE due to presence of a CVC) with “comparison cases” (HA-VTE unrelated to the child’s CVC) [[9]Jaffray J. Branchford B. Goldenberg N. Malvar J. Croteau S.E. Silvey M. Fargo J.H. Cooper J.D. Bakeer N. Sposto R. Ji L. Development of a risk model for pediatric hospital-acquired thrombosis: a report from the Children’s Hospital-Acquired Thrombosis Consortium.J Pediatr. 2021; 228: 252-259.e1Abstract Full Text Full Text PDF PubMed Scopus (19) Google Scholar]. While this type of study design does not allow for determination of the incidence or overall risk of CRT, it allows for comparison of related populations (hospitalized children with a CVC), potentially reduces selection bias as no control group is needed, and can be useful in identifying more subtle or nuanced risk factors in a population with multiple subtypes [[10]Pogreba-Brown K. Austhof E. Ellingson K. Methodology minute: an overview of the case-case study design and its applications in infection prevention.Am J Infect Control. 2020; 48: 342-344Abstract Full Text Full Text PDF PubMed Scopus (4) Google Scholar]. In this cohort of 1144 hospitalized children with HA-VTE and a CVC, higher odds of CRT (compared to non-CRT) on multivariable analysis were seen in cases with peripherally inserted central catheters (PICCs), CVCs inserted in the femoral vein, having multiple CVCs, and/or having CVC malfunction. This study adds to the knowledge of risk for CRT across hospitalized pediatric patients with a diversity of diagnoses, including inflammatory bowel disease and other autoimmune and inflammatory conditions. It also raises concern for judicious use of PICC lines and femoral CVCs and should be considered in the therapeutic process when deciding if a PICC line is a reasonable choice or whether a central line can be placed in another location. The use of CVCs in hospitalized children has allowed many children to receive easier and successful treatment of their underlying critical or complex illnesses. However, this study affirms that CRT remains a significant complication and further studies are needed to assess both mechanical and pharmacologic prevention techniques to try and mitigate this risk. M.B. and A.B. contributed equally to the writing and editing of this manuscript. There are no competing interests to disclose.