Inhaled pressure of oxygen

So hyperoxic vasoconstriction is a local phenomenon where local blood flow adjusts to the requirements of the perfused tissues. Even more importantly, the recurrence of vasomotion in ischemic areas shows that the pace-maker function of the smooth muscle cells is once again at work -demonstrating an improvement in their metabolic condition87.

Four conclusions can be made from our study: (1) DO2 in ischemic areas is increased in HBO because there is an increase in the blood oxygen content and because local blood flow does not decrease; (2) hyperoxic vasoconstriction appearing in normally perfused areas is in fact an adjusted response of the vessels reducing the risk of oxygen toxicity; (3) vasoconstriction in correctly perfused areas combined with maintained blood flow in ischemic areas leads to a redistribution of blood flow into the poorly perfused areas. This phenomenon of vascular redistribution can play an important part in the beneficial effects of HBO in cases where perfusion is heterogeneously altered in organs - for instance in reperfusion syndromes; (4) the recurrence of vasomotion proves the improvement of the metabolic condition of the ischemic areas. This could be used as an objective to guide the use of HBO in clinical practice.

0 0

Post a comment