What is the first action a nurse should take when a fetal heart rate (FHR) is less than 100/min in a 38-week gestation patient?

Immediate Nursing Action for Fetal Heart Rate < 100 bpm at 38 Weeks

The nurse should immediately reposition the patient to the left lateral position (Option C) as the first action when fetal bradycardia is detected, followed by immediate provider notification while simultaneously implementing other intrauterine resuscitation measures.

Rationale for Immediate Repositioning

The clinical scenario describes fetal bradycardia (FHR < 100 bpm) in a term pregnancy with pre-existing concerning features (decreased variability and fetal movement on non-stress test). This represents a potential obstetric emergency requiring immediate intervention to optimize fetal oxygenation before definitive management 1.

Maternal repositioning to left lateral position is the most immediate, non-invasive intervention that can be performed within seconds and addresses the most common reversible causes of acute fetal bradycardia:

• Relieves aortocaval compression, improving maternal cardiac output and uteroplacental perfusion 1
• Alleviates potential umbilical cord compression by changing fetal position relative to the cord 1
• Can be initiated immediately without requiring equipment, orders, or additional personnel 1

Classification and Urgency

This FHR pattern represents NICHD Category III (abnormal) findings when bradycardia (< 110 bpm) occurs with absent baseline variability, which was already noted on the prior non-stress test 1. Category III tracings require immediate intervention to resolve the abnormal pattern or move toward expeditious delivery 1.

Prolonged deceleration is defined as FHR drop lasting > 2 minutes below baseline 2. If this bradycardia persists beyond 10 minutes, it becomes "terminal bradycardia" with significantly increased risk of hypoxic-ischemic brain injury and dyskinetic cerebral palsy 2.

Complete Intrauterine Resuscitation Protocol

While repositioning is the first action, the nurse must simultaneously implement a comprehensive intrauterine resuscitation protocol 1:

1. Reposition to left lateral (or right lateral if no improvement) 1
2. Immediately notify the provider while performing other interventions 1
3. Administer supplemental oxygen (8-10 L/min via face mask) 1
4. Perform vaginal examination to rule out umbilical cord prolapse or rapid fetal descent 1
5. Check maternal vital signs to identify maternal hypotension 1
6. Administer intravenous fluid bolus if hypotension present 1
7. Discontinue oxytocin if being administered 1
8. Consider acute tocolysis if uterine hyperstimulation present 2

Why Other Options Are Incorrect

Option A (Reassure mother) is contraindicated because:

• FHR < 100 bpm with pre-existing decreased variability represents a potentially ominous pattern 1
• Bradycardia with absent variability may predict current or impending fetal asphyxia 1
• False reassurance delays appropriate intervention and provider notification 1

Option B (Immediately notify provider) is essential but not the first action because:

• Notification takes time (locating provider, communicating findings) 1
• Reversible causes of bradycardia may resolve with immediate repositioning 2
• The nurse can reposition the patient in seconds while simultaneously calling for help 1
• Both actions should occur nearly simultaneously, but physical repositioning can begin instantly 1

Option D (Ask about fetal movement) is inappropriate as the first action because:

• This information was already obtained during the non-stress test (decreased fetal movement noted) 1
• Gathering additional history delays intervention for a potentially emergent situation 2
• Fetal movement assessment does not address the immediate bradycardia 1

Critical Timing Considerations

The window for intervention is narrow: if acute profound hypoxia continues, the fetus progresses from initial chemoreflex-mediated bradycardia to myocardial hypoxia within minutes 2. Recovery of FHR to baseline is most likely when:

• Normal variability was present before the deceleration 2
• Variability remains normal within the first 3 minutes of prolonged deceleration 2
• The underlying cause is reversed quickly 2
• Recovery typically occurs within 9 minutes if the cause is truly reversible 2

Common Pitfalls to Avoid

• Delaying repositioning while waiting for provider response - every second counts in acute fetal bradycardia 2
• Assuming bradycardia is benign - in the context of pre-existing decreased variability and decreased fetal movement, this represents high-risk findings 1
• Performing only one intervention - intrauterine resuscitation requires multiple simultaneous measures 1
• Failing to prepare for emergency delivery - if bradycardia persists despite interventions, expeditious delivery may be necessary 1

The nurse must recognize that this clinical scenario (term pregnancy with bradycardia and pre-existing concerning features) may rapidly progress to requiring emergency cesarean delivery if intrauterine resuscitation measures fail to restore normal FHR patterns 1, 2.