NCLEX Review Guide: Fetal Distress During Labor and Birth

Definition and Pathophysiology

• Fetal distress occurs when the fetus experiences inadequate oxygenation (hypoxia) during labor, leading to potential acidosis and compromised fetal well-being.
• Primary causes include uteroplacental insufficiency, cord compression, maternal hypotension, and prolonged labor which reduce oxygen delivery to the fetus.

Fetal Heart Rate Patterns

• Baseline bradycardia (<110 bpm) may indicate fetal hypoxia, especially when persistent and accompanied by decreased variability.
• Late decelerations are the most ominous sign, indicating uteroplacental insufficiency with gradual decrease in FHR after contraction peak.
• Variable decelerations suggest cord compression and appear as abrupt drops in FHR with contractions, varying in timing and severity.
• Absent or minimal baseline variability (<5 bpm fluctuation) indicates potential fetal central nervous system depression.

Priority Actions for Fetal Distress

1. Position mother on left side to relieve vena cava compression and improve uteroplacental blood flow.
2. Administer oxygen at 8-10 L/min via face mask to increase maternal oxygen saturation and fetal oxygenation.
3. Increase IV fluid rate to improve maternal blood volume and placental perfusion, unless contraindicated.
4. Discontinue oxytocin if infusing to reduce uterine contraction strength and frequency.
5. Perform vaginal examination to assess for cord prolapse and cervical dilation progress.
6. Notify physician immediately and prepare for potential emergency cesarean delivery.

Medical Management

• Amnioinfusion may be performed to relieve cord compression by instilling normal saline into the amniotic cavity through an intrauterine pressure catheter.
• Tocolytic medications like terbutaline may be administered to reduce uterine contractions and improve fetal oxygenation temporarily.
• Fetal scalp stimulation or vibroacoustic stimulation can assess fetal responsiveness and central nervous system integrity.
• Emergency cesarean delivery is indicated for persistent fetal distress unresponsive to conservative measures, typically within 30 minutes of decision.