Figure 2. Mixed venous PCO2and PO2(Pv with bar sub CO2and Pv with barO2, respectively) and arterial blood PO2(PaO2) (mean plus/minus SD, n = 5) in the control and stroma-free methemoglobin groups of dogs at baseline, after intravenous administration of stroma-free methemoglobin in the stroma-free methemoglobin group, and at the end of the cyanide infusion. *Significant difference (P < 0.05) from baseline. (dagger)Significant difference (P < 0.05) from the other measurements in the stroma-free methemoglobin group.