Fig. 2. Changes in venous PO2 (A) and O2
content (B) with time into apnea. Individual data points (see
Table 2 for labels of seals)
from each of the three venous compartments are indicated by color: extradural
vein (EDV; red), central veins (CV; green) and pulmonary artery (PA; blue);
curve fits indicating compartmental trends are shown in the same respective
colors. (A) Equation, from all data pooled (black line), for exponential rate
of PO2 decline:
y=43.7e(–x/4.30)+15.8
(r2=0.71, N=163). (B) Equation from pooled data
(black line) for linear depletion rate of O2 content:
y=–2.01x+26.0 (r2=0.54,
P<0.0001, N=163).