title: Development of a new risk score for hospital-associated venous thromboembolism in critically-ill children not undergoing cardiothoracic surgery.
abstract: BACKGROUND
  Although risk of hospital-associated venous thromboembolism (HA-VTE) differs between critically and non-critically ill children, studies to date have not led to distinct, pragmatic risk scores.
  
  
  OBJECTIVE
  To determine risk factors for HA-VTE in critically ill children not undergoing cardiothoracic surgery, in order to derive a novel HA-VTE risk score for this population.
  
  
  METHODS
  We conducted a retrospective analysis from January 2006 through April 2013 at All Children's Hospital Johns Hopkins Medicine. HA-VTE cases were identified using ICD-9 discharge diagnosis codes, with subsequent validation via radiologic record review. Cases were restricted to Pediatric Intensive Care Unit (PICU) admissions. Patients who underwent cardiothoracic surgery were excluded; cardiac catheterization per se was not exclusionary. For each case, three non-HA-VTE PICU controls were randomly selected. Data were abstracted on putative risk factors, and associations between risk factors and HA-VTE were estimated using odds ratios (ORs) and 95% confidence intervals (95%CIs).
  
  
  RESULTS
  There were 57 HA-VTE cases and 171 controls. HA-VTE occurrence was 3 per 1000 PICU admissions (0.3%). Central venous catheter (CVC) (OR:26.64; 95%CI:7.46-95.13), length of stay (LOS) ≥4days (OR:20.22; 95%CI:2.27-180.07), and significant infection (OR:3.41; 95%CI:1.13-10.29) were independent, statistically-significant risk factors for HA-VTE in a multivariate model. A risk score was derived in which HA-VTE risk exceeded 2% (threshold for anticoagulant thromboprophylaxis in hospitalized adults) with a score of 15, and was >1% but <2% (risk zone for mechanical thromboprophylaxis in hospitalized adults) with scores of 7-14.
  
  
  CONCLUSIONS
  The presence of a CVC, LOS≥4days and infection are significant risk factors for HA-VTE in critically ill children not undergoing cardiothoracic surgery, forming the basis for a new risk score that warrants prospective validation.
authors.affiliation: Clinical and Translational Research Organization, All Children's Research Institute, All Children's Hospital Johns Hopkins Medicine, St. Petersburg, FL, USA.
authors.forename: Shilpa J
authors.initials: SJ
authors.lastname: Arlikar
authors.affiliation: Undergraduate Medical Education, Department of Pediatrics, University of South Florida Morsani College of Medicine, Tampa, FL, USA.
authors.forename: Christie M
authors.initials: CM
authors.lastname: Atchison
authors.affiliation: Clinical and Translational Research Organization, All Children's Research Institute, All Children's Hospital Johns Hopkins Medicine, St. Petersburg, FL, USA.
authors.forename: Ernest K
authors.initials: EK
authors.lastname: Amankwah
authors.affiliation: Johns Hopkins Medicine Pediatric Thrombosis Program, All Children's Hospital and Johns Hopkins Children's Center, St. Petersburg, FL and Baltimore, MD, USA.
authors.forename: Irmel A
authors.initials: IA
authors.lastname: Ayala
authors.affiliation: Clinical and Translational Research Organization, All Children's Research Institute, All Children's Hospital Johns Hopkins Medicine, St. Petersburg, FL, USA; Johns Hopkins Medicine Pediatric Thrombosis Program, All Children's Hospital and Johns Hopkins Children's Center, St. Petersburg, FL and Baltimore, MD, USA.
authors.forename: Laurie A
authors.initials: LA
authors.lastname: Barrett
authors.affiliation: Section of Hematology/Oncology/Bone Marrow Transplantation, Department of Pediatrics, University of Colorado School of Medicine Anschutz Medical Campus and Children's Hospital Colorado, Aurora, CO, USA.
authors.forename: Brian R
authors.initials: BR
authors.lastname: Branchford
authors.affiliation: Division of Hematology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Michael B
authors.initials: MB
authors.lastname: Streiff
authors.affiliation: Johns Hopkins Medicine Pediatric Thrombosis Program, All Children's Hospital and Johns Hopkins Children's Center, St. Petersburg, FL and Baltimore, MD, USA; Division of Hematology, Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Clifford M
authors.initials: CM
authors.lastname: Takemoto
authors.affiliation: Clinical and Translational Research Organization, All Children's Research Institute, All Children's Hospital Johns Hopkins Medicine, St. Petersburg, FL, USA; Johns Hopkins Medicine Pediatric Thrombosis Program, All Children's Hospital and Johns Hopkins Children's Center, St. Petersburg, FL and Baltimore, MD, USA; Division of Hematology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Division of Hematology, Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD, USA. Electronic address: neil@jhmi.edu.
authors.forename: Neil A
authors.initials: NA
authors.lastname: Goldenberg
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D016638:Critical Illness / Q000628:therapy*; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D012307:Risk Factors; D019616:Thoracic Surgical Procedures / Q000009:adverse effects*; D054556:Venous Thromboembolism / Q000453:epidemiology; D055815:Young Adult
keywords: Children; Critical care; Prevention; Risk factor; Risk score; Venous thromboembolism