Hospital-Acquired Venous Thromboembolism among Children Undergoing Invasive Mechanical Ventilation

ABSTRACT

INTRODUCTION: Hospital-acquired venous thromboembolism (HA-VTE) has an incidence of 2.2% among critically ill children. Although risk factors have been described (e.g., immobility, central venous catheterization [CVC], and systemic inflammation), insufficient data exists to recommend routine thromboprophylaxis (TP) in the pediatric intensive care unit (PICU). Children undergoing mechanical ventilation (MV) may represent an at-risk population due to illness severity, intentional immobility, and frequent CVC presence. We sought to estimate the rate and timing of HAVTE for children undergoing MV and explore for variation in HA-VTE rates by MV parameters. METHOD(S) We performed a single-center, retrospective cohort study of children < 18 years of age in the PICU undergoing MV from October 2020 - March 2022 excluding those with tracheostomy, HA-VTE prior to MV, and a total MV exposure of < 24 hours. The primary outcome was HA-VTE identified after intubation confirmed by imaging. Secondary outcomes were HA-VTE characteristics (i.e., timing, location, and CVC-related), MV parameters (i.e., barometric, volumetric, and compliance data within 72-hours of intubation), and other known HA-VTE risk factors. Descriptive and comparative statistics (Fisher's exact, Wilcoxon rank sum, and Student's t tests) were employed. RESULT(S) Of 170 subjects studied, 18 (10.6%) developed a HA-VTE (limb deep venous thromboses) at median of 4 (interquartile range [IQR]1.4,6.4) days after intubation. Those with HA-VTE had a greater frequency of comorbid CVC (88.9% vs 61.8%, P=0.034) and prior history of HA-VTE (27.8% vs 8.6%, P=0.027). No differences in demographics, anthropometrics, severity of illness indices, immobility, applied TP, rates of comorbid hematologic malignancy, sepsis, COVID-19, trauma, or postoperative admission were noted. No differences were observed for rates of conventional MV, high-frequency oscillation, intubation timing, or MV duration. Ventilator parameters were not different between those with and without HA-VTE. CONCLUSION(S) In our study, the rate of HA-VTE among critically ill children undergoing MV was 10.6% and more common to children with comorbid CVC. Although HA-VTE rates were not observably different by MV exposure, duration, or intensity, prospective studies are still required.