Figure 3From: A simple breathing circuit allowing precise control of inspiratory gases for experimental respiratory manipulationsRespiratory traces of hyperoxic manipulations using the new circuit (right) vs. an oxygen mask (left). In the first row we show tests where 50% O2 and 100% O2 were administered in two different instances and in which flow rate was 15 L/min during the entire manipulation. In the second row we repeated the first experiments but increasing the flow rate to 30 L/min during 1 m:30s after transitions. Fractional concentrations are given as partial pressure with respect to an atmospheric pressure of 760 mmHg. FA = fractional concentration of administered O2; Fi = fractional concentration of inspired O2; ET model = model of the fractional concentration of expired O2; FR = flow rate.Back to article page