H(2)S in Critical Illness—A New Horizon for Sodium Thiosulfate?

Ever since the discovery of endogenous H(2)S and the identification of its cytoprotective properties, efforts have been made to develop strategies to use H(2)S as a therapeutic agent. The ability of H(2)S to regulate vascular tone, inflammation, oxidative stress, and apoptosis might be particularly useful in the therapeutic management of critical illness. However, neither the inhalation of gaseous H(2)S, nor the administration of inorganic H(2)S-releasing salts or slow-releasing H(2)S-donors are feasible for clinical use. Na(2)S(2)O(3) is a clinically approved compound with a good safety profile and is able to release H(2)S, in particular under hypoxic conditions. Pre-clinical studies show promise for Na(2)S(2)O(3) in the acute management of critical illness. A current clinical trial is investigating the therapeutic potential for Na(2)S(2)O(3) in myocardial infarct. Pre-eclampsia and COVID-19 pneumonia might be relevant targets for future clinical trials.