Introduction: Inhaled epoprostenol (iEPO) has various off label indications for use in critically ill patients. The aim of this study was to evaluate if use of and response to iEPO aligns with our institution’s clinical practice guideline. Methods: Single-center, retrospective, observational study of adult intensive care unit (ICU) patients who received iEPO for any indication. Patients were included if they received iEPO from November 2024 to June 2025. Primary endpoint was percentage of patients who received iEPO for an approved indication (heart transplant with pulmonary hypertension (PH), cardiac/assist device surgery with right ventricular failure, precapillary PH, congenital cardiac disease with PH, or life-threatening hypoxemia). Secondary endpoints included response to iEPO at 1 and 6 hours, duration of use, duration of mechanical ventilation (MV), length of stay (LOS), and mortality. Response was defined by clinical endpoints predetermined in our clinical practice guideline based on indication for use. Data were analyzed using chi-squared for dichotomous data and Mann-Whitney U for continuous data. Results: A total of 147 patients were included (median (IQR) age 59 (46-71) years, 65% male). Many had cardiac surgery (n=50, 34%) or acute respiratory distress syndrome (n=40, 27%). More patients received iEPO for a non-approved (n=76, 52%) than an approved indication (n= 71, 48%). Most common approved indication was life threatening hypoxemia (n=59, 83%). In those with an approved indication, 30% (n=21) were responders after 1 hour. An additional 16 patients responded after 6 hours. Nearly all the non-responders (n=33, 97%) continued use beyond 6 hours. ICU LOS was higher (15 vs 7.5 days, p=0.02) in responders, however there was no difference in duration of iEPO use (39 vs 29 hours, p=0.14), hospital mortality (51% vs 74%, p=0.054), or days alive and free of MV at day 28 (0 vs 0 days, p=0.31) between the responders and non-responders. Conclusions: Several patients received iEPO for an unapproved indication and many were continued on iEPO despite non-response. This warrants re-evaluation of our approved indications and education regarding iEPO use to reduce time and resources associated with inappropriate use.
Bishop et al. (Sun,) studied this question.