Abstract
Oxygen is a substance needed for aerobic metabolism. The process of ischemia and reperfusion are responsible for local changes in oxygen concentrations. Both subnormal and supranormal tissue oxygenations are dangerous. Monitoring of end-organ perfusion and oxygenation is essential for patients in the intensive care unit. Knowledge of the balance between supply and consumption of oxygen in the target organ tissue is necessary. An alternative possibility of measuring tissue oxygenation is near infra-red spectroscopy (NIRS) based on tissue transparency to the near infrared spectrum (NIR, wavelength 700–1000 nm), and its absorption by the relevant chromophores (oxy and deoxyhaemoglobin). The authors summarize current knowledge and practical experiences of neonatologists using NIRS in various indications – from the evaluation of immediate postpartum adaptation to its application as a part of intensive monitoring of critically ill newborns. NIRS directly and non-invasively measures the total light signal from microcirculation (from venous, arterial and capillary nets). NIRS is a modern non-invasive, continuous, real-time and bed-side monitoring of tissue oxygenation and in the future could be part of multimodal patient monitoring.