A method for estimating at least one local metabolic parameter of a tissue area of a patient, comprising the following steps: ∘ receiving light intensities measured for the tissue area being considered, said light intensities being measured by an acquisition device for at least three different wavelengths between 600 and 1000 nm, said wavelengths being chosen depending on the absorptivity of different types of hemoglobin, such as oxyhemoglobin and deoxyhemoglobin, the step of receiving consisting in receiving, for each wavelength, a plurality of light intensities measured at different times of a period of heart beat, ∘ selecting, for each wavelength, light intensities measured at least at one time of the cardiac cycle for which it is desired to estimate said and at least one local metabolic parameter, ∘ calculating, from the selected light intensities, absorbance values for the three wavelengths, ∘ determining, from the absorbance values calculated for the three wavelengths: - a concentration of oxyhemoglobin, - a concentration of deoxyhemoglobin, taking into consideration the tissue absorbance in the estimation of concentrations of oxyhemoglobin and deoxyhemoglobin, ∘ estimating at least one local metabolic parameter from the calculated concentrations of oxyhemoglobin and deoxyhemoglobin, wherein the step of selecting consists in selecting, from the set of measured light intensities, light intensities for which the amount of arterial blood is minimal in the tissue area being considered, so that the determined concentrations are representative of the concentration of oxyhemoglobin and deoxyhemoglobin in the venous blood. ∘ receiving light intensities measured for the tissue area being considered, said light intensities being measured by an acquisition device for at least three different wavelengths between 600 and 1000 nm, said wavelengths being chosen depending on the absorptivity of different types of hemoglobin, such as oxyhemoglobin and deoxyhemoglobin, the step of receiving consisting in receiving, for each wavelength, a plurality of light intensities measured at different times of a period of heart beat, ∘ selecting, for each wavelength, light intensities measured at least at one time of the cardiac cycle for which it is desired to estimate said and at least one local metabolic parameter, ∘ calculating, from the selected light intensities, absorbance values for the three wavelengths, ∘ determining, from the absorbance values calculated for the three wavelengths: - a concentration of oxyhemoglobin, - a concentration of deoxyhemoglobin, taking into consideration the tissue absorbance in the estimation of concentrations of oxyhemoglobin and deoxyhemoglobin, - a concentration of oxyhemoglobin, - a concentration of deoxyhemoglobin, ∘ estimating at least one local metabolic parameter from the calculated concentrations of oxyhemoglobin and deoxyhemoglobin, wherein the step of selecting consists in selecting, from the set of measured light intensities, light intensities for which the amount of arterial blood is minimal in the tissue area being considered, so that the determined concentrations are representative of the concentration of oxyhemoglobin and deoxyhemoglobin in the venous blood.