ABSTRACT
The skin essentially consists of two different layers: the epidermis, an avascular superficial layer of stratified epithelium, and underneath, the dermis, a layer of connective tissue including a complex system of skin vasculature. Nutritive capillaries ascend toward the epidermis where they bend and form capillary loops. The blood flow of these capillary loops supplies oxygen to the surrounding tissue and the epidermis above it. Carbon dioxide is produced by proliferating keratinocytes and diffuses through the stratum corneum into the atmosphere or through the dermis and is removed by the skin blood flow. A two-point calibration of the sensor is carried out with external gas mixtures and/or automatically using the measuring equipment. The process commonly called “cutaneous respiration” has been known for a long time.
