P0847 - Pediatric Venous Thromboembolism: Different Rates of Incidence, Anatomic Locations, and Risk Factors between Orthopaedic and Non-Orthopaedic Related Patients

Background/Purpose: The prevalence of venous thromboembolism (VTE) may be increasing in children; however, scarce literature exists comparing incidence rates between pediatric orthopaedic patients and other pediatric patients. The purpose of this study was to compare the incidence, anatomic locations, and risk factors of VTEs between orthopaedic and non-orthopaedic related pediatric patients.

Methods: Computed tomography and ultrasound data were reviewed for children (<19 years old) with a diagnosed VTE between January 1, 2009 and December 31, 2016. Demographic and clinical data, including VTE anatomic location and risk factors, were recorded. Two major cohorts were identified: 1.) Orthopaedic-related (ORTH) and 2.) Non-orthopaedic-related (NORTH) VTEs. Incidence rates were estimated and risk factors were compared using chi-square testing.

Results: There were 373 children diagnosed with a VTE (average age 10.3 years) out of a total of 810,097 treated as in-patients for an incidence rate of 4.60 per 10,000 cases (95% CI = 4.15 to 5.10 per 10,000 cases). The rate of ORTH VTEs (28 out of 188,669 orthopaedic patients, 1.48 per 10,000 cases) was significantly lower than that of NORTH VTEs (345 out of 621,428 non-orthopaedic patients, 5.55 per 10,000 cases; p<0.001). For the ORTH cohort, there was a significant difference in the proportion of deep vein thrombosis (DVT) in the lower extremity (91%) compared to the upper extremity (9%; p<0.001), while there was a more even distribution of NORTH DVTs in the upper (50%) and lower (41%) extremities. The primary risk factors for ORTH VTEs included surgery (93%; p<0.001), change in ambulatory status (61%; p<0.001), and trauma (18%; p<0.001), while the primary risk factors for NORTH VTEs included intravenous PICC/ central line (61%; p<0.001) and cancer (27%; p=0.001).

Conclusion: Pediatric orthopaedic-related VTEs have a significantly lower incidence rate and different primary risk factors than those of non-orthopaedic-related VTEs. This information is useful for health care providers and pediatric hospital systems when making decisions regarding risk and prophylaxis in pediatric patients with both orthopaedic and non-orthopaedic conditions.