Nebulized Heparin to Reduce COVID-19-induced Acute Lung Injury: A Prospective Observational Study

BACKGROUND: High mortality due to COVID-19 disease has been a serious concern, a few of the causes being disseminated intravascular coagulation (DIC) and venous thromboembolism. Considering this, some experts have used heparin. However, its role still needs to be validated. MATERIALS AND METHODS: This study predicts the role of nebulized heparin in decreasing the severity of lung injury caused by COVID-19. Thirty patients admitted with COVID-19 acute respiratory distress syndrome (ARDS) in the intensive care unit (ICU) of All India Institute of Medical Sciences, Rishikesh, were included in this study, which was conducted over a period of 3 months. Patients were nebulized with 2 mL of heparin 5,000 units/mL IV formulation diluted with 3 mL of 0.9% sodium chloride, every 6 hours for a total duration of 7 days. Improvement in oxygenation (ratio of partial pressure of oxygen in blood and fraction of inspired oxygen delivered, pO(2)/FiO(2) ratio) was calculated as the primary outcome. Other parameters like effect on inflammatory markers (neutrophil-lymphocyte ratio, total leukocyte count, interleukin (IL-6), and D-dimer values), time to liberate from mechanical ventilation, and hospital stay were calculated as secondary outcomes. RESULTS: In our study population, the mean age was 54.5 years and the majority of patients were males (79.0%). All patients received prone ventilation and none of them required tracheostomy. However, 5 patients (16.6%) succumbed to illness. After nebulization with unfractionated heparin, no statistically significant difference was seen in the neutrophil-lymphocyte ratio (mean = 6.87, p = 0.318) and interleukin (IL-6) levels (mean = 62.85, p = 0.6) over 7 days. Similarly, the D-dimer level also had no statistically significant change (mean = 1853.73 p = 0.570). However, there was a statistically significant improvement in oxygenation (pO(2)/FiO(2) ratio) over 7 days (mean = 184.96, p = 0.00). Similarly, there was a significant improvement in PaO(2) (84.17 ± 33.82) and SO(2) (92.30 ± 3.49). Although, no significant changes were seen in the partial pressure of carbon dioxide on nebulized heparin administration. CONCLUSION: Administration of nebulized heparin in COVID-19 pneumonia with mild ARDS may improve oxygenation and result in the improvement of inflammatory markers with variable sensitivity and specificity. HOW TO CITE THIS ARTICLE: Gupta B, Chandrakar S, Gupta N, Jain G. Nebulized Heparin to Reduce COVID-19-induced Acute Lung Injury: A Prospective Observational Study. Indian J Crit Care Med 2023;27(3): 222–224.