Table 2.
Performance of SpO2/FiO2 as a marker of PaO2/FiO2 when SpO2 ≤ 97 %
| Number of observations (n = 43) | Test characteristic | 95 % CI | ||||
|---|---|---|---|---|---|---|
| PaO2/FiO2 | ||||||
| ≤300 | >300 | Sensitivity | 83 % | 68–93 | ||
| SpO2/FiO2 | ≤315 | 34 | 1 | Specificity | 50 % | 1–99 |
| >315 | 7 | 1 | PPV | 97 % | 85–100 | |
| NPV | 13 % | 0–53 | ||||
| PaO2/FiO2 | ||||||
| ≤200 | >200 | Sensitivity | 70 % | 47–87 | ||
| SpO2/FiO2 | ≤235 | 16 | 2 | Specificity | 90 % | 68–99 |
| >235 | 7 | 18 | PPV | 89 % | 65–99 | |
| NPV | 72 % | 51–88 | ||||
CI confidence interval, FiO 2 fraction of inspired oxygen, NPV negative predictive value, PaO 2 partial pressure of oxygen, PPV positive predictive value, SpO 2 pulse oximetric oxygen saturation