Source / episode info
- **Episode:**338
- **Title:**Divine Intervention Episode 338 – Fetal Heart Rate Tracings Made Easy
- **Published:**2021-09-01
- Source:Episode page
One-liner
This episode reviews the interpretation of fetal heart rate tracings, covering normal ranges (110-160 bpm), defining accelerations (>15 bpm for 15 seconds) and decelerations, utilizing the V-E-A-L mnemonic (Variable, Early, Accelerations, Late), and detailing the distinct mechanisms and management of each type of deceleration.
High-yield summary
- Normal FHR: 110 to 160 beats per minute (bpm). Tachycardia >160 bpm; Bradycardia <110 bpm.
- Accelerations: Increase in FHR by 15 bpm for 15 seconds. Two accelerations in 20 minutes constitute a reactive Non-Stress Test (NST).
- Variable Decelerations (V): Caused by umbilical cord compression; characterized by an abrupt, downsloping V shape with a trough duration of <30 seconds. Management priority: Left Lateral Decubitus position -> Amnio infusion -> Stop Oxytocin.
- Early Decelerations (E): Caused by head compression activating the Cushing reflex; characterized by a gradual, symmetrical downsloping V shape that coincides with the peak of uterine contractions and lasts >30 seconds. No intervention needed as it is physiologic.
- Late Decelerations (L): Sign of uteroplacental insufficiency; characterized by a decrease in FHR that begins after the peak of the uterine contraction and lasts >30 seconds. Management priority: Left Lateral Decubitus position -> Amnio infusion -> Stop Oxytocin.
- V-E-A-L Mnemonic: V = Variable (Cord); E = Early (Head); A = Accelerations; L = Late (Placenta).
Learning objectives
- Differentiate the mechanisms, shapes, and timings of variable, early, and late fetal decelerations.
- Identify appropriate interventions for different types of nonreassuring FHR patterns (e.g., repositioning, fluid administration).
- Recognize physiological causes of fetal tachycardia (e.g., maternal fever, anemia, beta-blocker use).
- Interpret the Non-Stress Test (NST) results based on acceleration criteria.
- Understand the clinical significance of the V-E-A-L mnemonic in obstetrics.