Fetal heart tracing
From IDWiki
Components
- Baseline: normal range is from 110-160 bpm
- Variability
- Absent
- Minimal: less than 5 bpm
- Moderate (normal): 5 to 25 bpm (reassuring)
- Marked: more than 25 bpm
- Accelerations: rise from baseline of at least 15 bpm lasting at least 15 sec (or 10x10 if <30 weeks)
- Decelerations: decrease from baseline of at least 15 bpm lasting at least 15 sec (or 10x10 if <30 weeks)
- Early: associated with contractions, possibly related to head compression, and clinically benign
- Late: placental insufficiency or decreased perfusion to the fetus
- Variable: may reflect transient cord compression
- Prolonged: ≥15 bpm and lasting ≥2 minutes but <10 minutes; if > 10 min, then it's a baseline change
Classification
- Category I (normal/reassuring): all of the following must be present
- A baseline FHR of 110 to 160 bpm
- Moderate FHR variability (6 to 25 bpm)
- Absence of late or variable FHR decelerations
- Early decelerations may or may not be present
- Accelerations may or may not be present
- Category 2 (atypical/indeterminate/non-reassuring)
- Does not meet criteria for categories 1 or 2
- Not predictive of fetal outcomes
- Category 3 (abnormal/fetal distress): at least one of the following must be present
- Absent variability with recurrent late decelerations
- Absent variability with recurrent variable decelerations
- Absent variability with bradycardia
- A sinusoidal pattern
