Objective: To describe the use of tranexamic acid (TXA) in a population of cats with high-rise syndrome and associated cavitary bleeding.

Design: Retrospective case series.

Methods: Search of the hospital’s database from 2018 to 2019 for cats with high-rise syndrome that received TXA.

Complete history and signalment: 5 domestic short hair cats presented to the hospital with a history of high-rise syndrome after falling various heights (2nd–6th floor). Mean age in months and standard deviation (SD) were 7,6 and 3 respectively. There were 2 entire females and 3 entire males. Abnormal physical examination findings included weak pulses (4/5), altered mentation (3/5), tachypnea (3/5), epistaxis (2/5), mandibular instability (2/5), bradycardia (2/5), oral bleeding (2/5), carpal/tarsal instability (2/5), tachycardia (1/5) and subcutaneous emphysema (1/5).

Clinicopathological abnormalities included hyperglycemia (mean 212 mg/dL, SD 54,5), hyperlactatemia (mean 3,5 mmol/dL, SD 1,4) acidemia (mean pH 7,27, SD 0,08), alveolar patterns compatible with pulmonary contusions (5/5), pneumothorax (2/5), rib fractures (1/5), pelvic fractures (1/5), free thoracic fluid compatible with hemothorax (2/5) and free abdominal fluid compatible with hemoabdomen (5/5). The median abdominal fluid score (AFS) was 1 (interquartile range 0,5).

Therapy: All patients received TXA 10 mg/kg IV every 8 hours. Additional treatments administered were oxygen therapy via oxygen cage, maropitant, methadone, buprenorphine, meloxicam and crystalloid fluid therapy. None of the patients required a blood transfusion or a surgical procedure to control bleeding. All cats were discharged from hospital within four days.

Discussion: TXA is an antifibrinolytic drug that acts by blocking the lysine-binding site of the plasminogen molecules inhibiting its conversion into plasmin. The use of TXA has been previously described in dogs (traumatic and non-traumatic hemoabdomen, post-interventional bleeding in greyhounds and acute traumatic coagulopathy) but to the authors´ knowledge it has not been described in cats. The main adverse effect in canines is vomiting. The cats in our study received preemptive therapy with maropitant to avoid this complication. TXA appears to be safe in felines at the doses used in this study with preemptive antiemetics.