Table 2.

Physiologic conditions at the beginning and the end of ventilation

	Nonventilated room air	6 ml/kg tidal volume room air	30 ml/kg tidal volume room air
PH	7.40 ± 0.05	7.35 ± 0.02	7.33 ± 0.06
Arterial oxygen pressure (mmHg)	98.7 ± 0.6	82.3 ± 7.5	86.1 ± 1.3
Arterial carbon dioxide pressure (mmHg)	40.2 ± 0.5	39.1 ± 1.1	35.3 ± 1.9
Mean arterial pressure (mmHg)
Start	86 ± 1.9	85.3 ± 3.0	84.6 ± 2.3
End	85 ± 0.8	81.3 ± 2.2	73.5 ± 7.1
Peak inspiratory pressure (mmHg)
Start		9.5 ± 1.5	23.6 ± 2.6
End		11.7 ± 1.8	27.9 ± 3.8

Arterial blood gases and mean arterial pressure of normal nonventilated mice and of mice ventilated at tidal volumes of 6 ml/kg or 30 ml/kg for 5 hours (n = 10 per group).