A Retrospective Cohort Study of Tranexamic Acid Administration for the Treatment of Angiotensin-Converting Enzyme Inhibitor-Induced Angioedema in the Emergency Department.

Background: Treatment options for angiotensin-converting enzyme inhibitor-induced angioedema (ACEi-AE) are primarily limited to airway monitoring and protection with intubation. The efficacy of tranexamic acid (TXA) in this context remains poorly understood.

Objective: Examine outcomes among patients treated with and without TXA for ACEi-AE.

Methods: A retrospective cohort study conducted in two hospitals examined emergency department patients with suspected ACEi-AE from 2017 to 2021. Primary outcomes included intensive care unit (ICU) admission, intubation, days intubated, time to administration of TXA, surgical airway required, and death in patients that received TXA compared with those that did not.

Results: Of 336 eligible patients, 37 received TXA and 299 did not. ICU admission rate was significantly higher in the TXA group (57%) vs. the no-TXA group (15%), odds ratio (OR) 7.61 (95% confidence interval [CI] 3.69-15.70). There were significantly more intubations in the TXA group (20%) vs. the no-TXA group (5.7%), OR 3.87 (95% CI 1.49-10.08). The median time to TXA administration was 51 min (interquartile range 34-131). The number of days intubated, surgical airway, and 30-day mortality were not significantly different in the TXA group compared with the no-TXA group.

Conclusion: TXA use did not improve many of the clinical outcomes involved in the treatment of ACEi-AE. One interpretation of these results may be that TXA use was associated with patients who presented with more severe disease, as TXA use was up to the discretion of the treating physician. Randomized controlled trials are needed to clarify the efficacy of TXA use in ACEi-AE.