Associations between HR <100 bpm at 60 s after birth, newborn characteristics, treatment and short-term outcomes
| HR <100 bpm at 60 s (n=162) | HR ≥100 bpm at 60 s (n=4210) | Total (n=4372) | |
| P value | |||
| First HR (bpm) | 100 (80, 137) | 149 (114, 173) | <0.001 |
| Time to first HR (s) | 18 (12, 33) | 15 (10, 24) | <0.001 |
| HR at 30 s (bpm) | 120 (92, 156) | 170 (146, 187) | <0.001 |
| HR at 60 s (bpm) | 88 (80, 94) | 175 (157, 189) | <0.001 |
| Gestational age (weeks) | 40.1 (38.8, 40.9) | 40.3 (39.3, 41.0) | 0.080 |
| Birth weight (kg) | 3.59 (3.25, 3.90) | 3.58 (3.24, 3.91) | 0.740 |
| Gender | 0.998 | ||
| Female, number (%) | 80 (49) | 2093 (50) | |
| Male, number (%) | 82 (51) | 2117 (50) | |
| Apgar 1 min | 9 (9, 9) | 9 (9, 9) | <0.001 |
| Apgar 5 min | 10 (9, 10) | 10 (10, 10) | <0.001 |
| Apgar 10 min | 10 (10, 10) | 10 (10, 10) | <0.001 |
| Umbilical arterial pH | 7.25 (7.19, 7.29) | 7.24 (7.19, 7.29) | 0.754 |
| Time to cord clamping (s) | 273 (189, 373) | 307 (232, 400) | 0.004 |
| Mode of delivery | <0.001 | ||
| Spontaneous vaginal | 121 (75%) | 3304 (78%) | |
| Vacuum | 7 (4%) | 543 (13%) | |
| Forceps | 2 (1%) | 17 (<1%) | |
| Elective caesarean | 2 (1%) | 42 (1%) | |
| Acute caesarean | 25 (15%) | 238 (6%) | |
| Vaginal breech | 5 (3%) | 66 (2%) | |
| Delivery room PPV | 29 (18%) | 93 (2%) | <0.001 |
| Admission to the NICU | 32 (20%) | 367 (9%) | <0.001 |
| Tracheal intubation | 0 (0%) | 2 (<1%) | |
| Chest compressions | 1 (<1%) | 0 (0%) | |
| Hypothermia treatment | 0 (0%) | 3 (<1%) | |
| HIE | 2 (1%) | 9 (<1%) | |
| Death before discharge | 1 (<1%) | 0 (0%) |
HR, gestational age, births weight, Apgar and umbilical arterial pH is given as median (quartiles). Delivery room PPV, tracheal intubation, chest compressions, admission to the NICU, hypothermia treatment and HIE as number (%).
HIE, hypoxic ischaemic encephalopathy; HR, heart rate; NICU, neonatal intensive care unit; PPV, positive pressure ventilation.