Right Drug in the Wrong Place: The Effects of Inadvertent Intrathecal Tranexamic Acid.

Tranexamic acid (TXA) is an antifibrinolytic drug widely used to reduce blood loss in major surgeries and trauma patients, thus reducing morbimortality. In recent years, clinical indications for TXA have expanded, including many off-label uses. This broad use has led to an increased incidence of reported side effects and administration errors with serious neurological and cardiovascular outcomes, such as seizures, myoclonus, and arrhythmias. This case report describes a 75-year-old female, American Society of Anesthesiologists (ASA) physical status III, who underwent lumbar spine surgery and received topical TXA for hemostatic control despite intraoperative incidental dural tears. Postoperatively, the patient experienced severe back pain, perianal burning, and painful lower limb myoclonus, prompting emergency surgery to rule out surgical complications. Despite no structural issues being identified, her symptoms persisted, requiring reintubation, sedation, and ICU admission. On the first postoperative day, no further pain or myoclonus was present with analgosedation and mechanical ventilation weaning. The patient's clinical condition improved gradually, being discharged one week later with no further complaints or neurological sequelae. TXA reduces inhibitory neurotransmission of γ-Aminobutyric acid type A (GABA-A) and glycine receptors with increased neuronal excitability and potential proconvulsant properties. This mechanism of action is responsible for the clinical features of acute neurotoxicity with imbalanced inhibitory-excitatory motor, sensory, and autonomic neurotransmission following intrathecal TXA. This case report intends to increase awareness for early recognition of the neurotoxic effects following inadvertent intrathecal TXA. The authors are unaware of other reports regarding this clinical feature as a complication from spinal topical use, enhancing the importance of dural integrity before considering topical TXA administration. Any dural tear could allow TXA to enter the intrathecal space, potentially leading to severe neurotoxic effects. In conclusion, further studies are required to evaluate the safety, efficacy, and clinical indications for topical TXA, particularly in spine surgery, to provide a safer use of this promising drug.