Table 2.
Fetal pH, blood gases and metabolites before, during and after umbilical cord occlusion
| Group | Baseline | Occlusion | +1 h | +2 h | +4 h | +6 h | +24 h | +48 h | +72 h |
|---|---|---|---|---|---|---|---|---|---|
| pH | |||||||||
| Control | 7.37 ± 0.01 | 7.37 ± 0.01 | 7.37 ± 0.01 | 7.39 ± 0.01 | 7.37 ± 0.01 | 7.38 ± 0.01 | 7.37 ± 0.01 | 7.36 ± 0.01 | 7.36 ± 0.01 |
| 15 min | 7.36 ± 0.01 | 6.92 ± 0.01*δ | 7.33 ± 0.01*δ | 7.40 ± 0.01δ | 7.39 ± 0.01 | 7.37 ± 0.01 | 7.35 ± 0.01 | 7.36 ± 0.01 | 7.36 ± 0.00 |
| 25 min | 7.36 ± 0.01 | 6.84 ± 0.01# | 7.27 ± 0.02# | 7.32 ± 0.01# | 7.40 ± 0.01# | 7.40 ± 0.01 | 7.37 ± 0.01 | 7.37 ± 0.01 | 7.36 ± 0.01 |
| (mmHg) | |||||||||
| Control | 48.8 ± 1.2 | 47.0 ± 1.1 | 47.3 ± 1.1 | 47.4 ± 0.9 | 48.1 ± 1.1 | 47.5 ± 1.1 | 47.7 ± 1.1 | 47.6 ± 1.4 | 47.8 ± 1.5 |
| 15 min | 49.4 ± 0.9 | 114.5 ± 3.1*δ | 44.0 ± 0.6 | 45.6 ± 1.0 | 44.5 ± 1.1 | 46.7 ± 1.3 | 48.6 ± 1.0 | 48.4 ± 1.3 | 48.5 ± 1.3 |
| 25 min | 50.5 ± 1.3 | 141.6 ± 4.2# | 50.8 ± 3.6 | 48.2 ± 1.9 | 48.0 ± 1.3 | 47.4 ± 1.0 | 46.9 ± 1.1 | 47.1 ± 1.0 | 47.8 ± 1.1 |
| (mmHg) | |||||||||
| Control | 24.8 ± 0.7 | 24.5 ± 0.8 | 23.9 ± 0.9 | 24.9 ± 0.7 | 25.0 ± 0.6 | 24.7 ± 0.7 | 24.5 ± 1.0 | 24.6 ± 1.0 | 25.5 ± 1.2 |
| 15 min | 25.0 ± 0.6 | 7.6 ± 0.8* | 28.0 ± 0.6* | 26.5 ± 0.7 | 28.0 ± 0.7*δ | 26.1 ± 0.8 | 26.5 ± 0.6 | 25.6 ± 0.9 | 27.0 ± 0.9 |
| 25 min | 23.3 ± 0.6 | 9.4 ± 0.6# | 28.7 ± 2.2# | 25.9 ± 1.0 | 23.2 ± 0.9 | 24.1 ± 1.0 | 26.2 ± 1.1 | 27.9 ± 1.3 | 27.4 ± 1.2 |
| BE (mmol L−1) | |||||||||
| Control | 1.5 ± 0.5 | 1.6 ± 0.7 | 1.2 ± 0.7 | 2.7 ± 0.7 | 1.7 ± 1.0 | 2.4 ± 0.8 | 1.4 ± 0.8 | 1.1 ± 0.8 | 0.6 ± 0.6 |
| 15 min | 2.0 ± 0.4 | −9.6 ± 0.3*δ | −2.8 ± 0.4* | 2.6 ± 0.6δ | 1.7 ± 0.5 | 1.5 ± 0.6 | 0.8 ± 0.3 | 1.3 ± 0.7 | 1.3 ± 0.7 |
| 25 min | 2.3 ± 0.8 | −12.0 ± 0.6# | −4.0 ± 1.5# | −1.8 ± 1.0# | 3.2 ± 0.8 | 3.8 ± 0.7 | 0.8 ± 0.8 | 1.1 ± 0.8 | 0.6 ± 0.4 |
| Hct (%) | |||||||||
| Control | 26.7 ± 0.8 | 26.4 ± 1.0 | 26.8 ± 0.9 | 25.5 ± 2.1 | 26.3 ± 0.8 | 27.0 ± 1.0 | 27.2 ± 1.3 | 28.5 ± 1.8 | 29.6 ± 1.6 |
| 15 min | 25.3 ± 1.2 | 26.3 ± 1.6 | 23.9 ± 1.2δ | 25.7 ± 1.2 | 25.8 ± 1.1 | 25.4 ± 1.2 | 25.2 ± 1.3 | 26.3 ± 1.1 | 26.8 ± 1.4 |
| 25 min | 27.2 ± 0.9 | 27.7 ± 0.9 | 29.9 ± 1.6 | 28.5 ± 0.9 | 27.1 ± 0.8 | 27.6 ± 1.1 | 27.6 ± 1.1 | 26.6 ± 1.0 | 27.3 ± 1.1 |
| O2ct (mmol L−1) | |||||||||
| Control | 3.7 ± 0.1 | 6.0 ± 2.2 | 3.7 ± 0.2 | 3.9 ± 0.2 | 3.7 ± 0.2 | 3.8 ± 0.2 | 3.8 ± 0.2 | 5.9 ± 2.0 | 4.0 ± 0.2 |
| 15 min | 3.5 ± 0.2 | 0.3 ± 0.0*δ | 3.5 ± 0.2 | 3.8 ± 0.2 | 3.8 ± 0.2 | 3.7 ± 0.2 | 3.6 ± 0.2 | 3.7 ± 0.2 | 4.0 ± 0.3 |
| 25 min | 3.6 ± 0.1 | 0.5 ± 0.0# | 4.2 ± 0.3 | 4.0 ± 0.2 | 3.8 ± 0.2 | 3.9 ± 0.2 | 4.0 ± 0.2 | 4.1 ± 0.2 | 4.2 ± 0.2 |
| Lactate (mmol L−1) | |||||||||
| Control | 0.7 ± 0.1 | 0.8 ± 0.0 | 0.9 ± 0.1 | 0.8 ± 0.0 | 0.8 ± 0.1 | 0.9 ± 0.1 | 0.8 ± 0.0 | 0.8 ± 0.0 | 0.8 ± 0.1 |
| 15 min | 0.8 ± 0.1 | 5.2 ± 0.2*δ | 3.1 ± 0.1*δ | 1.5 ± 0.1δ | 1.0 ± 0.1δ | 1.0 ± 0.1δ | 0.8 ± 0.1δ | 0.9 ± 0.0 | 0.8 ± 0.0 |
| 25 min | 0.8 ± 0.1 | 7.0 ± 0.2# | 5.0 ± 0.5# | 4.3 ± 0.4# | 2.7 ± 0.4# | 2.3 ± 0.3# | 1.2 ± 0.1# | 0.9 ± 0.1 | 0.8 ± 0.1 |
| Glucose (mmol L−1) | |||||||||
| Control | 1.0 ± 0.1 | 1.0 ± 0.0 | 1.1 ± 0.1 | 1.1 ± 0.1 | 1.1 ± 0.1 | 1.1 ± 0.1 | 1.1 ± 0.1 | 1.0 ± 0.0 | 1.0 ± 0.1 |
| 15 min | 1.2 ± 0.0 | 0.7 ± 0.1* | 1.6 ± 0.1* | 1.7 ± 0.1*δ | 1.6 ± 0.01* | 1.6 ± 0.0* | 1.2 ± 0.1 | 1.2 ± 0.1* | 1.2 ± 0.1 |
| 25 min | 1.0 ± 0.1 | 0.8 ± 0.1# | 1.4 ± 0.1# | 1.4 ± 0.1# | 1.4 ± 0.1# | 1.5 ± 0.1# | 1.3 ± 0.1# | 1.2 ± 0.1# | 1.1 ± 0.1 |
Samples during occlusion were taken at either 12 min after the start of umbilical cord occlusion (15 min group) or 17 min after the start of umbilical cord occlusion (25 min group). , arterial partial pressure of carbon dioxide in arterial blood; , arterial partial pressure of oxygen in arterial blood; BE, base excess; Hct, haematocrit; O2ct, arterial blood oxygen content. Data are the mean ± SEM. * P < 0.05, 15 min vs. control; # P < 0.05, 25 min vs. controls; δ P < 0.05, 15 min vs. 25 min.