Septic and hemorrhagic shock
It can be hypothesized that peripheral vasoconstriction, induced by hyperoxia, may be beneficial in septic and hemorrhagic shock, reducing the need for intravenous volume resuscitation and vasopressor requirements. Furthermore, hyperoxia exerts anti-inflammatory effects and may even have antimicrobacterial properties in humans [45]. To date, however, no studies have shown benefits of reaching supranormal oxygen levels. In fact, hyperoxia may impair oxygen delivery in patients with sepsis [46]. Moreover, hyperoxia decreases whole-body oxygen consumption in critically ill patients [47]. The Surviving Sepsis Campaign guidelines recommend that peripheral oxygen saturation be maintained between 88% and 95% in sepsis patients with acute respiratory distress syndrome and do not advocate hyperoxia [48]. In hemorrhagic shock, increasing the fraction of inspired oxygen does not affect survival but does compromise hemodynamics [49].