Safety and Duration of Intrathecal Alteplase via IRRAflow for Intraventricular Hemorrhage

Introduction: Intraventricular hemorrhages (IVH) can have a mortality rate between 50-80%. IVH may result in hydrocephalus and elevated intracranial pressure that is traditionally managed with external ventricular drains (EVDs). However, EVDs are associated with complications such as infection, occlusion, and device replacement. IRRAflow is a closed loop ventricular irrigation and drainage system that allows for cerebrospinal fluid (CSF) exchange and intrathecal drug delivery without disruption of a sterile system. The purpose of this study was to assess the safety and duration of intrathecal (IT) alteplase via IRRAflow for evacuation of IVH within our institution.


Methods: This was a single center retrospective analysis of patients admitted to the neurocritical care unit from March 1, 2022 through May 17, 2025. Patients who received IT alteplase via IRRAflow were included. Patients were excluded if they did not have IVH or if their use of IRRAflow deviated from standard institutional practice. Duration of alteplase irrigation was assessed using time of IT alteplase initiation and discontinuation. Safety outcomes included the incidence of hemorrhage expansion, infection, occlusion, and device replacement.


Results: A total of 83 patients were reviewed and 51 met inclusion criteria. In most patients, IT alteplase was administered via alteplase 2mg in 500mL normal saline irrigation at a rate of ≤ 60 mL/min. The median duration of IRRAflow was 184 hours, while the median duration of IT alteplase administration was 46 hours. There were 5 (9.8%) incidences of hemorrhage expansion during alteplase irrigation, however discontinuation of therapy was rare (2%). The median time for hemorrhage expansion was 20 hours. There was a low incidence of CSF infection (5.8%), IRRAflow replacement (3.9%), and no device occlusions.


Conclusions: Given the low incidence of clinically significant hemorrhagic expansion, infection, catheter occlusion, and replacement, continuous IT alteplase via IRRAflow should be considered safe. The observed rate of hemorrhage expansion was lower than what has been reported in the literature with traditional EVDs. To our knowledge, this is the largest retrospective cohort study of alteplase administration via IRRAflow, supporting its potential role in the management of intraventricular hemorrhage.