Table 2.
Computer analysis of FHR tracings in cases with and without major MHR-FHR ambiguities, before and after their removal
| N | Before | After | p | |
|---|---|---|---|---|
| No major MHR-FHR ambiguity | ||||
| Signal loss (%) mean (SD) | 17 | 13 (7) | 14 (7) | <0.001 |
| Basal FHR (bpm) mean (SD) | 17 | 140 (10) | 140 (10) | 1.000 |
| Accelerations (n) median (IQR) | 17 | 9 (3 to 15) | 9 (3 to 15) | 0.157 |
| Sporadic decelerations (n) median (IQR) | 17 | 3 (2 to 11) | 3 (1 to 8) | 0.317 |
| Prolonged decelerations (n) median (IQR) | 17 | 0 (0 to 0) | 0 (0 to 0) | 1.000 |
| Abnormal LTV (%) median (IQR) | 17 | 3 (0 to 7) | 3 (1 to 11) | 0.317 |
| Alarm n (%) | 17 | 1.000 | ||
| Green-Blue | 14 (82) | 14 (82) | ||
| Yellow-red | 3 (18) | 3 (18) | ||
| Major MHR-FHR ambiguity | ||||
| Signal loss (%) mean (SD) | 44 | 22 (11) | 28 (13) | <0.001 |
| Basal FHR (bpm) mean (SD) | 44 | 136 (13) | 136 (12) | 0.129 |
| Accelerations (n) median (IQR) | 44 | 7 (4 to 10) | 6 (3 to 10) | 0.285 |
| Sporadic decelerations (n) median (IQR) | 44 | 8 (6 to 10) | 6 (4 to 10) | 0.001 |
| Prolonged decelerations (n) median (IQR) | 44 | 0 (0 to 1) | 0 (0 to 0) | 0.046 |
| Abnormal LTV (%) median (IQR) | 44 | 1 (0 to 3) | 1 (0 to 3) | 0.414 |
| Alarm n (%) | 44 | 0.021 | ||
| Green-Blue | 15 (34) | 23 (52) | ||
| Yellow-red | 29 (66) | 21 (48) | ||
| Overall | ||||
| Signal loss (%) mean (SD) | 61 | 20 (11) | 24 (13) | <0.001 |
| Basal FHR (bpm) mean (SD) | 61 | 137 (12) | 137 (12) | 0.129 |
| Accelerations (n) median (IQR) | 61 | 7 (4 to 10) | 7 (3 to 10) | 0.170 |
| Sporadic decelerations (n) median (IQR) | 61 | 7 (4 to 10) | 6 (3 to 9) | 0.001 |
| Prolonged decelerations (n) median (IQR) | 61 | 0 (0 to 1) | 0 (0 to 0) | 0.046 |
| Abnormal LTV (%) median (IQR) | 61 | 1 (0 to 4) | 2 (0 to 5) | 0.197 |
| Alarm n (%) | 0.021 | |||
| Green-Blue | 29 (48) | 37 (61) | ||
| Yellow-red | 32 (52) | 24 (39) |
SD standard deviation, IQR inter-quartile range
p values with statistical significance are displayed in bold