A method for in vitro diagnosing asphyxia and disorders related thereto, a method of in vitro estimating duration of hypoxia in a patient subjected to asphyxia, and a method for in vitro monitoring of normoxic, hypoxic and hyperoxic conditions and/or normobaric and hyperbaric oxygen therapy, includes quantitatively detecting in a biological sample of a patient a plurality of asphyxia specific endogenous compounds which are selected from the group consisting of biogenic amines; carnitine-derived compounds; amino acids; bile acids; carboxylic acids; eicosanoids; lipids; precursors of cholesterol, cholesterol metabolites; prostanoids; and sugars.