Obgyn · Year 3 · from Obgyn

Case 2: Non-Reassuring Fetal Heart Rate Tracing and Intrauterine Resuscitation

Patient Demographics

  • Age: 31 years
  • Sex: Female
  • Occupation: Marketing manager

Chief Complaint

"The nurse said the baby's heart rate is dropping."

History of Present Illness

The patient is a G2P1 at 40 weeks 1 day undergoing induction of labor for post-dates. She received misoprostol for cervical ripening followed by oxytocin augmentation. She has been in active labor for 4 hours and just received epidural analgesia. Shortly after the epidural was placed, the fetal heart rate monitor shows recurrent variable decelerations with slow return to baseline.

Current Labor Status

  • Cervix: 6 cm dilated, 90% effaced, 0 station
  • Oxytocin running at 12 milliunits/minute
  • Recent epidural placement with patient supine
  • Amniotic fluid clear when membranes ruptured 3 hours ago

Fetal Heart Rate Findings

  • Baseline: 150 bpm
  • Variability: Minimal (decreased from moderate prior to decelerations)
  • Decelerations: Recurrent variable decelerations to 80 bpm, lasting 60-90 seconds, with slow return to baseline
  • Accelerations: Absent

Diagnosis

Category II Fetal Heart Rate Tracing with:

  • Recurrent variable decelerations (suggesting cord compression)
  • Minimal variability (concerning in context of decelerations)

Immediate Intrauterine Resuscitation

Step 1: Position Change

  • Patient repositioned from supine to left lateral decubitus
  • If no improvement, try right lateral, then hands-and-knees position

Step 2: Discontinue Oxytocin

  • Oxytocin infusion stopped immediately to reduce uterine activity

Step 3: IV Fluid Bolus

  • 500 mL lactated Ringer's bolus administered to improve maternal perfusion

Step 4: Oxygen

  • Supplemental oxygen 10 L/min by face mask (consider if hypoxic)

Step 5: Cervical Examination

  • Performed to rule out cord prolapse
  • No cord palpable; cervix 6 cm, vertex at 0 station

Step 6: Assess for Tachysystole

  • Contraction frequency: 3-4 in 10 minutes (not tachysystole)

Response to Resuscitation

After 5 minutes:

  • Variable decelerations persist but less severe (nadir 90 bpm)
  • Variability improved to moderate
  • Baseline stable at 145 bpm

After 15 minutes:

  • Decelerations resolved
  • Category I tracing restored
  • Oxytocin restarted at lower rate (8 milliunits/minute)

Subsequent Labor Course

  • Labor progressed without further significant decelerations
  • Complete dilation at 4 hours after resuscitation
  • Spontaneous vaginal delivery
  • Infant vigorous at birth, Apgar 8/9

Teaching Points

Variable Decelerations:

  • Caused by umbilical cord compression
  • Characterized by abrupt onset and return
  • Mild variables are common and usually benign
  • Recurrent severe variables require intervention

When to Consider Emergent Delivery:

  • Prolonged deceleration >10 minutes not responding to resuscitation
  • Category III tracing (absent variability with recurrent late or variable decelerations, bradycardia, or sinusoidal pattern)
  • Evidence of cord prolapse

Documentation:

  • Time and nature of abnormality
  • Interventions performed and timing
  • Response to each intervention
  • Communication with team

Clinical Image

Image Description: Electronic fetal heart rate monitoring strip demonstrating variable decelerations with abrupt onset and variable timing relative to contractions. The lower channel shows uterine contraction pattern.

Attribution: Image from medical education resources. Used for educational purposes.


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