Table 2.
Primary and secondary outcomes after the intervention
| Low-normal PaCO2 group (n = 61) | High-normal PaCO2 group (n = 59) | P value | Normoxia group (n = 61) | Moderate hyperoxia group (n = 59) | P value | |
|---|---|---|---|---|---|---|
| Primary outcome | ||||||
| Median (IQR) NSE at 48 h after cardiac arrest, µg/la | 18.8 (13.9–28.3) | 22.6 (14.8–34.9) | 0.290 | 22.4 (14.8–28.3) | 20.6 (14.2–34.9) | 0.649 |
| Secondary outcomes | ||||||
| Neurologic recovery at 6 months after cardiac arrest | ||||||
| Good, CPC score 1–2, n (%) | 43 (71) | 35 (59) | 0.200 | 42 (69) | 36 (61) | 0.368 |
| Mortality 30 days after cardiac arrest, n (%) | 15 (25) | 23 (39) | 0.090 | 18 (30) | 20 (34) | 0.605 |
| Median (IQR) duration of intensive care, hb | 92 (66–136) | 104 (79–147) | 0.120 | 97 (73–140) | 100 (76–143) | 0.810 |
| Median (IQR) duration of mechanical ventilation, hc | 63 (47–97) | 75 (52–110) | 0.589 | 61 (47–95) | 74 (52–115) | 0.211 |
| Severe adverse events | ||||||
| Severe hypercapnia and respiratory acidosis (PaCO2 > 10 kPa and pH < 7.15), n (%) | 0 (0) | 1 (2) | 0.307 | 1 (2) | 0 (0) | 0.323 |
| Unexplained brain oedema on CT scanning, n (%) | 0 (0) | 1 (2) | 0.307 | 1 (2) | 0 (0) | 0.323 |
| Severe ARDS (PaO2/FiO2 < 100 mmHg), n (%) | 0 (0) | 2 (3) | 0.147 | 1 (2) | 1 (2) | 0.981 |
PaCO2 arterial carbon dioxide tension, IQR interquartile range, NSE neuron-specific enolase, CPC cerebral performance category [1, good cerebral performance (normal life); 2, moderate cerebral disability (disabled but independent); 3, severe cerebral disability (conscious but disabled and dependent); 4, coma or vegetative state (unconscious); 5, brain death], CT computed tomography, ARDS acute respiratory distress syndrome, FiO2 fraction of inspired oxygen
aData missing for 1 patient
bData missing for 6 patients
cData missing for 3 patients