A model is introduced for the oxygen consumption in thin vital tissue preparation. The steady uptake kinetics is modelled by a Michaelis–Menten form and for this case it proved that the resulting boundary value problem admits a unique solution for those parameter ranges typical of related physiological experiments. This solution is compared with Otto Warburg's hyperoxia model and with a hypoxia model. Useful and easily computed approximations are derived for the minimum oxygen supply across the tissue and some numerical solutions of the governing equations are discussed.