Minerva anestesiologica
-
Given the low physical solubility of oxygen (O2) in plasma, little value is attached to hyperoxic ventilation (FiO2 1.0) as a modality for improving O2 transport and tissue oxygen supply when hypoxemia (i.e., O2 partial pressure (paO2) <60 mmHg) is absent. Because recent experimental and clinical data conflict with this notion, we used mathematical modeling to reevaluate efficacy of hyperoxic ventilation in improving tissue oxygenation in the absence of hypoxemia by specifying its theoretical efficacy in terms of hemoglobin (Hb) equivalents. ⋯ Hyperoxic ventilation establishes a highly available source of O2 that can be utilized effectively for tissue oxygenation. Although further experimental studies are required to quantify this theoretically calculated amount of utilizable O2, these results suggest that the tissue oxygenation efficacy of hyperoxic ventilation, even in absence of hypoxemia, is grossly underestimated in daily clinical practice.