Mechanical Thromboprophylaxis and Hospital-Acquired Venous Thromboembolism Among Critically Ill Adolescents: A U.S. Pediatric Health Information Systems Registry Study, 2016-2023.

Objectives: To estimate the rate of mechanical thromboprophylaxis (mTP) prescription among critically ill adolescents using a multicenter administrative database and determine whether mTP prescription is inversely associated with hospital-acquired venous thromboembolism.

Design: Multicenter, observational, retrospective study of the Pediatric Health Information Systems (PHIS) Registry cohort, January 2016 to December 2023.

Setting: Thirty PICUs located within quaternary pediatric referral centers in the United States.

Patients: Critically ill children 12-17 years old, excluding encounters with a principal diagnosis at admission of venous thromboembolism.

Interventions: mTP prescription within the first 24 hours of hospitalization.

Measurements and main results: A total of 107,804 children met the study criteria, of which 21,124 (19.6%) were prescribed mTP. Hospital center prescribing rates ranged from 1.4% to 65.4% and decreased by 1.6% per year from 28.2% in 2016 to 17.1% in 2023. As compared with those without mTP, those with mTP more frequently had a concurrent central venous catheter (17.2% vs. 9.4%, p < 0.001), underwent invasive mechanical ventilation (37.4% vs. 24.8%, p < 0.001), were admitted for a primary surgical indication (30.9% vs. 12.7%, p < 0.001), and experienced a longer median duration of hospitalization (7 [interquartile range (IQR): 4-15] vs. 4 [IQR: 2-9] d, p < 0.001). Hospital-acquired venous thromboembolism occurred in 2.7% of the study sample and was more common among those with, as compared with without, prescription of mTP (4% vs. 2.4%, p < 0.001). In multivariable logistic regression models for hospital-acquired venous thromboembolism adjusting for salient prothrombotic risk factors, we failed to identify an association between mTP and greater odds of hospital-acquired venous thromboembolism (HA-VTE) among low-, moderate-, and high-risk tiers. However, we cannot exclude the possibility of 17-50% greater odds of HA-VTE in this population.

Conclusions: In the multicenter PHIS cohort, 2016-2023, the prescribing patterns for mTP among critically ill adolescents showed a low rate of mTP prescription (19.6%) that varied widely across institutions, decreased annually over the study period by 1.6%/year, and was not independently associated with HA-VTE risk reduction.