Characteristics of the cohort of eligible patients
| Early TH (n=54) | Late TH (n=37) | P value | |
| C-section, n (%) | 35 (64.8) | 16 (43.2) | 0.04 |
| Male sex, n (%) | 31 (57.4) | 23 (62.2) | 0.7 |
| Gestational age, mean (SD) | 39.0 (1.7) | 39.1 (1.4) | 0.7 |
| BW (kg), mean (SD) | 3.35 (0.65) | 3.31 (0.55) | 0.8 |
| Resuscitation score, median (IQR) | 5 (5–6) | 4 (4–5) | 0.001 |
| Apgar score at 10 min, median (IQR) | 4 (3–5) | 4 (4–6) | 0.1 |
| Arterial cord blood pH, mean (SD) | 6.9 (0.2) | 7.0 (0.2) | 0.2 |
| Who initiated TH? n (%) | <0.0001 | ||
| Centre before advice | 25 (46.3) | 3 (8.1) | |
| Centre after advice | 19 (35.2) | 11 (29.7) | |
| Transport team | 9 (16.7) | 18 (48.6) | |
| NICU | 1 (1.9) | 5 (13.5) | |
| How was TH initiated?* n (%) | 0.5 | ||
| Passive | 38 (71.7) | 19 (59.4) | |
| Passive, followed by cold packs | 12 (22.6) | 10 (28.6) | |
| Cold packs | 3 (5.7) | 3 (8.6) | |
| Time of referral to CHEO (hours), median (IQR) | 1.3 (0.8–1.7) | 2 (1.4–4) | 0.0003 |
| Time of arrival of transport team, median (IQR) | 2.3 (1.8–3.3) | 4.6 (3–5.9) | <0.0001 |
| Time of initiation of TH, median (IQR) | 1.4 (0.6–2) | 4.4 (4–6.4) | <0.0001 |
| Time to target temperature, median (IQR) | 4.3 (3.1–6.7) | 7.4 (6.4–8.9) | 0.007 |
| Degree of encephalopathy before TH | 0.03 | ||
| Normal or Sarnat 1, n (%) | 14 (25.9) | 11 (29.7) | |
| Sarnat 2, n (%) | 23 (42.6) | 23 (62.2) | |
| Sarnat 3, n (%) | 12 (31.5) | 3 (8.11) | |
| Abnormal cerebral function monitoring† | 0.2 | ||
| Discontinuous | 6 (14) | 5 (17.2) | |
| Burst suppression | 7 (16.3) | 7 (24.1) | |
| Low amplitude or flat trace | 9 (20.9) | 1 (3.4) | |
| Seizures | 29 (59.2) | 20 (40.8) | 1.0 |
| Death | 13 (24.1) | 3 (8.1) | 0.05 |
*For patients with TH initiation before their admission to NICU (53 patients in early TH and 32 patients in late TH).
†Cerebral Function Monitoring performed in 43 patients in early TH and 29 patients in late TH.
BW, birth weight; CHEO, Children’s Hospital of Eastern Ontario; C-section, caesarean section; NICU, neonatal intensive care unit; TH, therapeutic hypothermia.