Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Theoretical calculations of the Alveolar-arterial PO2 difference (AaPO2) (upper panel) and peripheral O2 extraction (lower panel) during peak exercise as a function of standard and in vivo P50 (ranges indicated by solid and dashed lines, respectively). While extraction increases essentially linearly with P50 over a wide range, AaPO2 falls with P50 only when the latter is lower than about 20 mmHg. These outcomes help explain the observations in Figure 4.
