Demographic details of the study population
| Birth characteristics | All infants | HIE Median (IQR) | Non-HIE Median (IQR) | P value |
| Gestation | 39.0 (37.7–40.3) | 39.5 (38.2–40.6) | 39.0 (37.7–40.3) | 0.12 |
| Birth weight (grams) | 3420 (3020–3800) | 3290 (2915–3650) | 3440 (3030–3800) | 0.04 |
| Sex | N (%) | N (%) | ||
| Male | 612 (56) | 40 (52) | 572 (57) | 0.47 |
| Female | 469 (43) | 36 (47) | 433 (43) | |
| Mode of delivery | n=1081(%) | n=76 (%) | n=1005 (%) | |
| Spontaneous vaginal | 213 (19.7) | 18 (23.7) | 195 (19.4) | 0.005 |
| Operative vaginal | 270 (24.9) | 29 (38.15) | 241 (23.9) | |
| Caesarean section | 598 (55.2) | 29 (38.15) | 569 (56.5) | |
| Prelabour c-section | 348 (32.1) | 5 (6.6) | 343 (34.0) | |
| Type of blood gas | n=1081 (%) | n=76 (%) | n=1005 (%) | |
| Arterial | 20 (1.9) | 13 (17.1) | 7 (0.7) | <0.001 |
| Venous | 926 (85.6) | 55 (72.4) | 871 (86.6) | |
| Capillary | 135 (12.4) | 8 (10.5) | 127 (12.6) | |
| Diagnosis | HIE N (%) | Non-HIE N (%) | ||
| Mild HIE | – | 37 (48.7) | – | |
| Moderate HIE | – | 29 (38.2) | – | |
| Severe HIE | – | 10 (13.1) | – | |
| Respiratory (TTN/RDS) | – | – | 449 (44%) | |
| Perinatal asphyxia | – | – | 231 (22.9%) | |
| Suspected infection | – | – | 167 (16.5%) | |
| Low birth weight | – | – | 37 (3.6%) | |
| Congenital anomalies | – | – | 29 (2.8%) | |
| Haemorrhage (subgaleal, maternal) | – | – | 27 (2.6%) | |
| Meconium aspiration | – | – | 16 (1.5%) | |
| Cardiac | – | – | 13 (1.2%) | |
| Neurological (non-encephalopathic) | – | – | 5 (0.5%) | |
| Hypoglycaemia | – | – | 3 (0.3%) | |
| Dysmorphic features | – | – | 2 (0.2%) | |
| Miscellaneous | 26 (2.58%) | |||
| Apgar Scores | All infants | HIE | Non-HIE | |
| At 1 min | 8 (5- 9) | 2 (1- 4) | 8 (5- 9) | <0.001 |
| At 5 min | 9 (7 -9) | 5 (3- 7) | 9 (8- 9) | <0.001 |
| First postnatal gas | All infants | HIE | Non-HIE | |
| pH | 7.25 (7.19–7.29) | 7.14 (7.05–7.23) | 7.25 (7.20–7.29) | <0.001 |
| Base deficit | 4.0 (2.0–6.8) | 11.7 (7.9–15.9) | 3.7 (1.9–6.1) | <0.001 |
| Lactate | 3.8 (2.2–6.8) | 9.6 (7.4–12.8) | 3.5 (2.1–6.2) | <0.001 |
HIE, hypoxic ischaemic encephalopathy; RDS, respiratory distress syndrome; TTN, transcient tachypnoea of the newborn.