TABLE 6.

The influence of 30 s, 60 s, and 120 s oscillations of 80/20 and 30/70 O2/N2 concentrations on alveolar-arterial oxygen difference.

Testing period	Mean	SD	p-value
30 s oscillation rate
Pre	1.04	7.04
Mid	1.49	9.69	0.99
Post	−2.18	5.09	0.58
Recovery	−2.71	4.99	0.45
60 s Oscillation rate
Pre	0.16	4.18
Mid	−2.17	3.29	0.59
Post	−1.52	6.42	0.79
Recovery	−0.03	8.03	0.99
120 s Oscillation Rate
Pre	2.44	4.84
Mid	−0.08	3.55	0.69
Post	−1.50	4.06	0.34
Recovery	1.64	6.21	0.98

SD, standard deviation. Bolded p-values denote a significant difference between that testing period and the pre exposure testing period (p < 0.05).