Table 3.
Performance of various values of PetCO2 and duration of CPR for predicting ROSC in all patients with cardiac arrest
| PetCO2 | Cut-off (kPa [mmHg]) | n | Min-max (kPa [mmHg]) | Mean ± SD (kPa [mmHg]) | Sensitivity (%) | Specificity (%) | PPV (%) | NPV (%) | AUROC (95% CI) |
| Initial | ≤1.3 (≤10) | 168 | 0.0–1.3 (0.0–10) | 0.68 ± 0.34 (5.1 ± 2.5) | 100 | 50 | 71 | 100 | 0.68 (0.63–0.72) |
| >1.3 (>10) | 569 | 1.4–8.7 (10.1–65.4) | 3.52 ± 1.93 (26.3 ± 14.5) | ||||||
| 0 to 10 minutes | ≤1.6 (≤12.1) | 306 | 0.3–1.6 (2.3–12.1) | 0.96 ± 0.34 (7.2 ± 2.6) | 100 | 91 | 93 | 100 | 0.99 (0.99–1.00) |
| >1.6 (>12.1) | 431 | 1.7–5.6 (12.2–42.1) | 2.79 ± 0.82 (20.9 ± 0.8) | ||||||
| 10 minutes | ≤1.3 (≤9.8) | 202 | 0.3–1.3 (2.3–9.8) | 0.85 ± 0.31 (6.4 ± 2.1) | 100 | 60 | 75 | 100 | 0.99 (0.98–0.99) |
| >1.3 (>9.8) | 535 | 1.4–7.2 (9.9–54.2) | 2.89 ± 1.09 (21.7 ± 8.2) | ||||||
| 11–15 minutes | ≤1.7 (≤12.8) | 333 | 0.4–1.7 (3.1–12.8) | 0.99 ± 0.30 (7.6 ± 2.2) | 100 | 99 | 99 | 100 | 1.00 (0.99–1.00) |
| >1.7 (>12.8) | 404 | 1.8–5.5 (12.8–41.4) | 3.19 ± 0.77 (23.9 ± 4.8) | ||||||
| 15 minutes | ≤1.8 (≤13.6) | 328 | 0.2–1.8 (1.5–13.5) | 1.11 ± 0.39 (8.4 ± 2.8) | 100 | 98 | 98 | 100 | 0.99 (0.99–1.00) |
| >1.8 (>13.6) | 409 | 1.9–7.7 (13.6–57.9) | 3.65 ± 0.98 (27.8 ± 7.4) | ||||||
| 20 minutes | ≤1.9 (≤14.3) | 335 | 0.3–1.9 (2.3–14.3) | 0.92 ± 0.29 (6.8 ± 2.1) | 100 | 100 | 100 | 100 | 1.00 (1.00–1.00) |
| >1.9 (>14.3) | 402 | 2.1–7.8 (14.4–58.7) | 4.36 ± 1.11 (33.1 ± 8.4) | ||||||
| Maximal | ≤2.3 (≤17.3) | 293 | 0.7–2.3 (5.3–17.3) | 1.58 ± 0.34 (12.1 ± 2.6 | 100 | 87 | 91 | 100 | 0.99 (0.99–1.00) |
| >2.3 (>17.3) | 444 | 2.4–10.7 (18.1–80.5) | 5.12 ± 1.57 (38.4 ± 11.9) | ||||||
| Final | ≤1.7 (≤12.8) | 335 | 0.2–1.7 (1.7–12.8) | 0.98 ± 0.33 (7.4 ± 3.2) | 100 | 99 | 99 | 100 | 1.00 (1.00–1.00) |
| >1.7 (>12.8) | 402 | 1.9–6.6 (14.3–49.7) | 0.98 ± 0.33 (27.8 ± 7.2) |
AUROC, area under the receiver operating characteristic curve; CI, confidence interval; CPR, cardiopulmonary resuscitation; NPV, negative predictive value; PetCO2, partial pressure of end-tidal carbon dioxide; PPV, positive predictive value; ROSC, return of spontaneous circulation; SD, standard deviation