Intrapartum Hypoxic Damage is detected by Hypoxia Index to Prevent Cerebral Palsy
Author(s): Kazuo Maeda
Aims: To prevent fetal brain damage and cerebral palsy (CP).
Methods: The hypoxia index was studied to solve the vague late deceleration (LD). Hypoxic fetal brain damage was known by the loss of variability. Early delivery before the loss of variability will prevent cerebral palsy, however, no numeric sign of the loss of variability was present, which was seeked by the author in the summing hypoxic effect in repeated FHR deceleration, where the sum of durations of FHR deceleration (min) was divided by the lowest FHR (bpm) and multiplied by 100, in the hypoxia index (HI), in the full FHR monitoring course, possibly using a computer.
Results: The Hi was 25 & 26 in CP and severe brain damage, while 20-24 in abnormal FHR but neither brain damage nor cerebral palsy with significant differences. Thus, a numeric threshold in HI to develop cerebral palsy was 25, and the safe HI is 24 or less. The CP will be prevented by the early delivery when the HI is less than 25.
Discussion: As HI was 6 in 3 connected LD while HI was 26 after 50 min’s LD repetition, the outcome depends on the repetition, but not to the LD pattern, and all of early, late, variable decelerations and continuous fetal bradycardia are evaluated by HI, namely, HI decides outcome, instead of deceleration pattern, where outcome is digitally diagnosed using numeric HI.
Conclusion: HI covers the role of all decelerations, while FHR pattern was discarded in computerized FHR diagnosis.