Background: Inhaled pulmonary vasodilators are used as adjunctive therapies for the treatment of refractory hypoxemia. Available evidence suggest they improve oxygenation in a subset of patients without changing long-term trajectory. Given the differences in respiratory failure due to COVID-19 and “traditional” ARDS, we sought to identify their physiologic impact. Methods: This is a retrospective observational study of patients mechanically ventilated for COVID-19, from the ICUs of 2 tertiary care centers, who received inhaled epoprostenol (iEpo) for the management of hypoxemia. The primary outcome is change in PaO 2 /FiO 2 . Additionally, we measured several patient level features to predict iEpo responsiveness (or lack thereof). Results: Eighty patients with laboratory confirmed SARS-CoV2 received iEpo while mechanically ventilated and had PaO 2 /FiO 2 measured before and after. The median PaO 2 /FiO 2 prior to receiving iEpo was 92 mmHg and interquartile range (74 – 122). The median change in PaO 2 /FiO 2 was 9 mmHg (-9 – 37) corresponding to a 10% improvement (-8 – 41). Fifty-percent (40 / 80) met our a priori definition of a clinically significant improvement in PaO 2 /FiO 2 (increase in 10% from the baseline value). Prone position and lower PaO 2 /FiO 2 when iEpo was started predicted a more robust response, which held after multivariate adjustment. For proned individuals, improvement in PaO 2 /FiO 2 was 14 mmHg (-6 to 45) vs. 3 mmHg (-11 – 20), p = 0.04 for supine individuals; for those with severe ARDS (PaO 2 /FiO 2 < 100, n = 49) the median improvement was 16 mmHg (-2 – 46). Conclusion: Fifty percent of patients have a clinically significant improvement in PaO 2 /FiO 2 after the initiation of iEpo. This suggests it is worth trying as a rescue therapy; although generally the benefit was modest with a wide variability. Those who were prone and had lower PaO 2 /FiO 2 were more likely to respond.
【저자키워드】 COVID-19, ARDS, inhaled epoprostenol, 【초록키워드】 Treatment, SARS-CoV2, therapy, Respiratory failure, prone, ICU, Laboratory, management, Hypoxemia, Patient, Inhaled, trajectory, predict, Evidence, retrospective, Oxygenation, interquartile range, Primary outcome, severe ARDS, Variability, mechanically ventilated, multivariate adjustment, baseline value, feature, benefit, robust, IMPROVE, predicted, identify, lack, clinically, receiving, median, increase in, individuals, subset, respond, PaO, tertiary care centers, the median, 【제목키워드】 respiratory, Epoprostenol, failure, responsiveness,