Device for determining the hemoglobin count of a patient

A method for the determination of a hemoglobin amount of a patient using a carbon monoxide administration device, the carbon monoxide administration device having a closed gas volume, a gas outlet including a mouthpiece configured to enable inhalation and exhalation of gas into and out of the closed gas volume, and a carbon monoxide reservoir that provides a carbon monoxide supply into the closed gas volume, the carbon monoxide reservoir having a volume which is provided with sensors for the determination of temperature and pressure of the carbon monoxide in the carbon monoxide reservoir, wherein the method comprises the steps of:

• i) supplying a defined amount of carbon monoxide to the closed gas volume;
• ii) in and exhaling the gas in the closed gas volume by the patient;
• iii) non-invasively determining the amount of carbon monoxide in the blood of the patient;
• iv) determining the hemoglobin value based on the amount of carbon monoxide in the blood of the patient, wherein the method comprises before step i) the steps:
• supplying pure oxygen into the closed gas volume;
• and
• in- and exhaling of the supplied pure oxygen by the patient.