(815) Inhaled Tranexamic Acid for Pulmonary Hemorrhage in Pediatric Oncology and Stem Cell Transplant

Introduction: Pulmonary hemorrhage is a life-threatening complication in oncology and hematopoietic stem cell transplant (HSCT) patients. Tranexamic acid (TXA) is a lysine analog and anti-fibrinolytic medication that has systemic and topical applications. Nebulized inhaled TXA (iTXA) is a promising option for the management of pulmonary hemorrhage. We investigated the impact of iTXA on the management of pulmonary hemorrhage in pediatric oncology and HSCT patients.

Methods: We conducted a retrospective observational study at a quaternary children’s hospital. Pediatric patients with an oncologic diagnosis or history of HSCT who were treated with iTXA for pulmonary hemorrhage and admitted to the intensive care unit (ICU) were included (January 2018 - August 2022). The ISTH bleeding score was utilized for the severity of the bleeding. Coagulation studies, transfusion requirements, respiratory parameters, and outcome measures were evaluated between survival and non-survival groups.

Results: Thirty-four patients, 20 oncology (59%) and 14 HSCT (41%), were included. Mean age was 11±7 yrs with 53% female gender. The average ISTH bleeding score was 5±2 with a hemoglobin drop of 1.8±1 g/dL. 79% required mechanical ventilation (MV). Pulmonary infections (bacterial, viral, fungal) were the most common etiology (69%). The majority of HSCT patients experienced transplantation-associated thrombotic microangiopathy (TA-TMA, 75%). Overall, 25 (71%) survived the pulmonary hemorrhage (survival group) and 36% died without recovery of pulmonary hemorrhage (non-survival group). There was no difference in coagulation parameters, blood product transfusion, and duration of MV between the groups. There was a significantly less peak end-expiratory pressure (PEEP) requirement (9±3 vs 12±2, P= 0.02) and a significant improvement of oxygenation index (OI) in the survival group (10 ±10 vs 24±21, P= 0.02). There were no drug-related complications.

Conclusions: Pulmonary hemorrhage has high mortality and morbidity in pediatric oncology and HSCT patients. iTXA is a safe and effective tool for managing pulmonary hemorrhage, and its use can significantly impact the care progression in this highly complex patient population.