Lecture Notes on Fetal Assessment and Monitoring

Importance of Fetal Assessment and Monitoring

• Fetal assessment is crucial during labor.
• Fetal monitoring involves using a fetal monitor to track the fetal heart rate and detect contractions.
• Monitoring can be intermittent or continuous based on doctor's orders.
• Aims to reduce long-term neurological effects.
• Critically used in over 80% of laboring women.

Types of Fetal Monitoring

1. External Monitoring

   • Requires knowledge of reading tracings.
   • Boxes on the tracing indicate time: each box = 10 seconds; highlighted lines = 1 minute.
   • Ultrasound transducer with gel is placed on the mother's abdomen.
   • Key features to identify:
     • Baseline Heart Rate: Normal range is 110-160 bpm.
     • Variability: Four types - Absent, Minimal, Moderate, and Marked.
     • Accelerations: Increase in heart rate by 15 bpm for at least 15 seconds.
     • Decelerations: Opposite of accelerations, can be early, late, variable, or prolonged.
   • Measures frequency and duration of contractions, but not strength (requires palpation).

2. Internal Monitoring

   • Requires ruptured membranes.
   • More precise measurement of fetal heart rate and contraction strength.
   • Involves a fetal scalp electrode or intrauterine pressure catheter (IUPC).
   • IUPC provides exact strength of contractions and calculates Montevideo units (MVUs).

Understanding Variability in Fetal Heart Rate

• Absent Variability: No fluctuation - indicates possible fetal distress.
• Minimal Variability: 0-5 bpm - could indicate fetal sleep or effects of narcotics.
• Moderate Variability: 5-25 bpm - indicates a healthy fetal neurological system.
• Marked Variability: Over 25 bpm - unclear significance.

Categories of Fetal Heart Rate Tracings

1. Category I: Reassuring

   • Baseline 110-160 bpm
   • Moderate variability
   • No late or variable decelerations, accelerations may be present or absent.

2. Category II: Not Reassuring

   • Baseline abnormalities; minimal or absent variability; presence of variable or late decelerations.

3. Category III: Requires Immediate Intervention

   • Sinusoidal pattern, absent variability with recurrent decelerations.

Decelerations in Fetal Heart Rate

• Early Decelerations: Mirrors contractions, indicates head compression.
• Late Decelerations: Caused by uteroplacental insufficiency, requires immediate action.
• Variable Decelerations: Abrupt changes indicating cord compression.
• Prolonged Decelerations: Lasts more than 2 but less than 10 minutes.

Interventions for Abnormal Tracings

• Position Change
• Oxygen Administration
• IV Fluid Increase
• Sterile Vaginal Exam
• Turn Off Pitocin
• Notify Physician
• Amnioinfusion: Used for oligohydramnios or variable decelerations.
• Tocolytics: Magnesium sulfate or Terbutaline.

Conclusion

• Proper documentation of fetal monitoring is critical.
• Fetal monitoring helps ensure the well-being of the fetus during labor.
• Nurses must be aware of their scope of practice based on state regulations.

Note

• For additional understanding or queries, reach out to the course professor.