This study will recruit 90 patients from Instituto Nacional de Ciencias Médicas Salvador Zubiran in México City. The study will begin in April 2017. The patients will be randomized to one of 2 groups of treatment (Spironolactone 25 mg or placebo). All treatments looks identical (1 capsule), will be administered through the nasogastric tube. Neither the patients nor their doctors will be able to know or decide which group you are in. You will receive the medication during the first five days of stay in the critical care unit.