Table 1.
Demographic and ventilatory parameters for all infants, showing differences in variables between those who were successfully extubated and those who failed.
| All infants (n = 48) | Extubation success (n = 35) | Extubation failure (n = 13) | p value | |
|---|---|---|---|---|
| Gestational age (weeks) | 27.2 (25.6 to 30.4) | 27.7 (25.6 to 31.3) | 27.0 (26.0 to 27.8) | 0.417 |
| Birth weight (g) | 940 (760 to 1115) | 935 (690 to 1185) | 970 (765 to 1090) | 0.808 |
| Male gender | 29 (60.4) | 23 (65.7) | 6 (46.2) | 0.218 |
| Postmenstrual age (weeks) | 30.2 (27.9 to 32.0) | 31.3 (29.0 to 33.7) | 28.0 (26.9 to 28.6) | 0.004 |
| Duration of mechanical ventilation (days) | 4 (2 to 10) | 4 (2 to 9) | 5 (2 to 10) | 0.967 |
| Fraction of inspired oxygen pre study | 0.25 (0.21 to 0.30) | 0.23 (0.21 to 0.30) | 0.25 (0.23 to 0.29) | 0.280 |
| Haematocrit pre study (%) | 41.1 (38.9 to 49.2) | 42.8 (39.1 to 52.8) | 40.8 (38.2 to 44.1) | 0.164 |
| Mean airway pressure pre study (cmH20) | 8.4 (7.0 to 10.3) | 8.3 (6.9 to 9.9) | 9.6 (7.8 to 10.9) | 0.244 |
| Partial pressure of carbon dioxide pre study (kPa) | 5.6 (4.7 to 6.3) | 5.3 (4.7 to 6.3) | 5.7 (4.7 to 6.8) | 0.560 |
| Caffeine pre study (Y) | 39 (88.6) | 27 (87.1) | 12 (92.3) | 0.619 |
| Sedation at time of study (Y) | 10 (21.7) | 7 (21.2) | 3 (23.1) | 0.982 |
| Spontaneous breathing trial (SBT) pass | 45 (94) | 33 (94.3) | 12 (92.3) | 0.801 |
| % change EMG amplitude (µV) | 32.8 (10.3 to 81.6) | 29.6 (8.4 to 85.2) | 35.9 (14.2 to 52.2) | 0.618 |
| % change EMGAUC (µV.S) | 7.4 (−5.2 to 38.2) | 3.4 (−10.0 to 24.6) | 31.8 (6.4 to 55.6) | 0.019 |