(801) Hospital-Acquired Venous Thromboembolism Among Chronically Immobilized Children With Tracheostomy

Introduction: Immobility is a prothrombotic risk factor related to venous stasis and is believed to increase the risk of hospital-acquired venous thromboembolism (HA-VTE). We sought to characterize the prevalence of acute and chronic immobility and the frequency of HA-VTE among critically ill children with tracheostomy.

Methods: We performed a retrospective cohort study of children 0-17 years of age admitted to a tertiary pediatric intensive care unit from Oct 2020 - May 2023 with a tracheostomy excluding those with a known VTE on admission. The primary outcomes were the prevalence of acute (e.g., Braden Q mobility scores) and chronic (e.g., bed-bound state prior to admission) immobility. The secondary outcome was the frequency of HA-VTE, including deep venous thrombosis and pulmonary embolism. Demographics, admission diagnoses, severity of illness indices, inherited prothrombotic conditions, central venous catheterization (CVC), thromboprophylaxis, length of stay (LOS), and mortality were recorded. Descriptive (e.g., proportions and medians), comparative (e.g., Fisher’s exact and Wilcoxon rank-sum tests), and associative (e.g., Logistic regression) statistics were employed, as appropriate.

Results: A total of 346 encounters and 180 unique patients encounters met study criteria. Median age of 3.6 years (IQR:1.8-22.6), Pediatric Risk of Mortality Probability of Death of 0.6% (IQR:0.3-1.1%), LOS of 5.2 days (IQR:2.5-10.7), and mortality was 3.2%. Principal diagnoses were pulmonary conditions (58.1%) and infectious diseases (52.9%, predominantly tracheitis 49.7%). None had an inherited prothrombotic condition, 17.9% a prior VTE, and 15.6% a CVC. Median Braden Q on admission was 1 (IQR:1-2) indicating 75% were completely or very immobilized at presentation. Regarding chronic immobility, 59% were bed-bound, 80.6% chronically ventilated, 93% intellectually/developmentally delayed, and 29.5% resided in a long-term care facility. Three (0.9%) patients developed a HA-VTE, of which two were CVC-related.

Conclusions: These findings suggest that, among critically ill children with tracheostomy, the prevalence of acute and chronic immobility is high, but the frequency of HA-VTE is low. Further investigation is warranted in a larger multicenter cohort to inform optimal HA-VTE prevention measures in this population.