Fig. 1.

Pulse oximetry in the bleomycin model of lung injury. A: dynamics of oxygen saturation (SpO₂) levels in bleomycin-injured and uninjured (sham-injured with NaCl) mice over the course of 12 days following injury. Only bleomycin-injured mice dropped SpO₂ levels below 90% (dashed line) that were significantly lower than in uninjured mice beginning on day 8. B: SpO₂ curves extracted from Windaq files of bleomycin-injured and uninjured mice prior to the beginning of the experiment and 12 days after injury. Note visible changes in the SpO₂ curve of injured animals (bleomycin day 12). C and D: although no significant changes from preinjury baseline recordings (day 0) were detected, heart rates of bleomycin-injured mice were significantly lower on day 12 and breath rates were significantly lower on days 4, 6, and 12 compared with uninjured mice. E: weight changes normalized to preinjury (day 0). Significant weight changes were noted on day 6 and constituted ∼20% weight loss in injured mice. P values were calculated between uninjured and bleomycin-injured groups at each time point by 1-tailed t-test. *P < 0.05, **P < 0.01.