TABLE 1.
BLOOD GASES AND OXYGENATION
| pH | Pco2 (mm Hg) | Hco3 (mmol/L) | O2 Saturation | |
| Control | 7.195 ± 0.0295 | 62.03 ± 9.00 | 24.03 ± 1.86 | > 92% |
| LTV | 7.194 ± 0.0251 | 57.15 ± 5.05 | 21.66 ± 0.81 | > 92% |
| HTV | 7.187 ± 0.0381 | 55.89 ± 5.60 | 20.05 ± 1.03 | > 92% |
| NS | NS | NS | NS |
Definition of abbreviations: HTV, high tidal volume; LTV, low tidal volume; NS, no significance; ± SEM.
In a subset of mice, a terminal blood sample was obtained by cardiac puncture for blood gas analysis. Oximetry was measured at 15-minute intervals during ventilation, using a Mouse Ox system. No differences in pH, Pco2, or Hco3 were evident between the three experimental groups. All mice demonstrated acute hypercapnic acidosis, consistent with previously published studies, and were well matched to spontaneously breathing anesthetized control mice. No measurable hypoxia occurred in any of the mice studied during these 4-hour experiments.