Patients will be randomized to the hydrocortisone or placebo arm using web-based, centralized permuted block randomization, stratified by centre. All study personnel (the overall study research coordinator, research assistants, site investigators, principal investigator, co-investigators, data management personnel, and statisticians), members of the health care team (treating physicians, bedside nurses, and clinical pharmacists) and patients/families will be blinded to the study group assignment.