Fetal Monitoring and Uterine Activity iRAT Cedarville University Junior Nursing OB

Fetal Monitoring

Method to measure fetal wellbeing and uterine activity.

External Tocodynamometer (Toco)

Pressure-sensing device placed on fundus measuring contraction frequency and duration.

Intrauterine Pressure Catheter (IUPC)

Internal device measuring contraction frequency, duration, resting tone, and intensity in mm Hg.

Ruptured membranes and cervix dilated 2-3 cm.

Prerequisites for IUPC Insertion

Fetal Scalp Electrode (FSE)

Internal direct EKG monitor applied to fetal scalp; requires ruptured membranes.

Uterine Activity Monitor Display

Displayed on the lower pane of the monitor paper (0-100 mm Hg).

Fetal Heart Rate

Displayed on the upper pane of the monitor paper.

Contraction Resting Tone

Pressure of the uterus between contractions during uterine relaxation.

Contraction Frequency

Time from the beginning of one contraction to the beginning of the next.

Fewer than 5 contractions in 10 minutes.

Normal Contraction Frequency

Tachysystole

More than 5 contractions in a 10-minute window.

Contraction Duration

Length of time a contraction lasts from start to end, measured in seconds.

Soft like cheek

Palpation Intensity: Indicates no contraction.

Tip of nose

Palpation Intensity: Indicates a mild contraction.

Chin

Palpation Intensity: Indicates a moderate contraction.

Forehead

Palpation Intensity: Indicates a strong contraction.

Baseline rate, variability, accelerations, and decelerations.

4 Essentials of FHR Tracing

110 to 160 beats per minute.

Normal Fetal Heart Rate Baseline

Minimum Time for Baseline FHR Segment

At least 2 minutes of continuous tracing (ideally 10 minutes).

Baseline FHR greater than 160 bpm.

Fetal Tachycardia

Maternal fever, dehydration, maternal anxiety, and early fetal hypoxia.

Common Causes of Fetal Tachycardia

Baseline FHR less than 110 bpm.

Fetal Bradycardia

Vagal stimulation, maternal hypotension, cord compression, and monitoring maternal pulse.

Common Causes of Fetal Bradycardia

Detected baseline FHR amplitude range of 5 bpm or less.

Minimal Variability

Normal baseline FHR amplitude range of 6 to 25 bpm.

Moderate Variability

Baseline FHR amplitude range greater than 25 bpm.

Marked Variability

Periodic changes occur with contractions; episodic changes occur independently.

Periodic vs Episodic FHR Changes

Increase ≥15 bpm lasting ≥15 seconds, returning to baseline

FHR Acceleration (≥32 weeks)

Increase ≥10 bpm lasting ≥10 seconds.

FHR Acceleration (

FHR acceleration lasting between 2 and 10 minutes.

Prolonged Acceleration

Fetal head compression (benign response).

Early Deceleration Cause

Nadir coincides exactly with the peak of the contraction.

Early Deceleration Pattern

Uteroplacental insufficiency (requires immediate intervention).

Late Deceleration Cause

Nadir and recovery occur after the peak and end of contraction.

Late Deceleration Pattern

Umbilical cord compression.

Variable Deceleration Cause

Abrupt drop ≥15 bpm lasting ≥15 seconds; often U, V, or W shaped.Variable Deceleration Pattern

Variable Deceleration Pattern

FHR drop ≥15 bpm lasting between 2 and 10 minutes.

Prolonged Deceleration

Normal baseline (110-160), moderate variability, no late/variable decels.

Category I Tracing Criteria

Left side position, IV fluids, Oxygen, Notify provider, Stop Pitocin.

LIONS Interventions for Decelerations

Amnioinfusion

Instillation of NS/LR via IUPC to treat variable decels or oligohydramnios.

Every 30 minutes in First Stage active phase.

Monitoring Frequency: Active Phase (Low Risk)

Every 5 minutes during pushing.

Monitoring Frequency: Second Stage (High Risk)