Probing Brain Oxygenation Waveforms with Near Infrared Spectroscopy (NIRS)

Le résumé fourni par la source

Breathing may have dramatic effects on the human cerebral blood flow (CBF) and cognition.This was already known long time ago to Chinese (Li Xiuling, 2003), Hindus (Kuvalayananda, 1983) and Tibetans (Mullin, 1996).The main parameter influencing the CBF is the arterial partial pressure of carbon dioxide (PaCO 2 ).About 70% increase in PaCO 2 may double the blood flow (Sokoloff, 1989, Guyton, 1991).The increase of blood flow to the brain results in an increase of nutrients and oxygen, which may influence to great extent brain's physiology.On the other hand lowering the PaCO 2 through hyperventilation found an application in neurosurgery (Feihl and Perret, 1994).An evaluation of the CBF dependence on PaCO 2 was given by Gersten (Gersten, 2011).The human normal value of PaCO 2 is about 40 mmHg.Fig. 1 depicts our estimation of the changes of CBF as a result of changing PaCO 2 from normal.The estimate is based on the data of Refs.(Reivich 1964, Ketty and Schmidt 1948, Raichle et all 1970).An increase of only 12.5% from normal in PaCO 2 leads to the state of hypercapnia (PaCO 2 above 45 mm Hg).With aging both CBF and PaCO 2 tends to fall down, therefore breathing exercises (or procedures) with the aim to increase PaCO 2 and CBF might be important in preventing and alleviating neurodegenerative diseases.They may be also important in improving intellectual abilities.The amount of PaCO 2 in our arteries is proportional to the CO 2 which was metabolized by the organism and inversely proportional to the lung ventilation (i.e. to the amount of air exchanged between the lungs and the environment in one minute).www.intechopen.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.