Methods
This pilot trial was an open, randomised, parallel group study investigating the effect of nebulised unfractionated sodium heparin (Cristalia Ltda; Brazil, 25,000 IU) in patients admitted to two hospitals in the state of Sao Paulo, Brazil (Sao Roque Hospital and Santa Casa de Sorocaba Hospital) between February 25th, 2021, and July 14th, 2021. The trial identification UTN code is U111-1263-3136 and all patients gave their written informed consent to participate in this study which was approved by the Ethics Committee of the University of Sao Paulo – Biomedical Sciences Institute.