Labor and Delivery: Part Two

Monitoring Fetal Status and Fetal Heart Rate (FHR)

• Fetal Heart Rate as an Indicator: The fetal heart rate is a primary indicator of the condition of the fetus during labor.

• Frequency of Monitoring:     * During the First Stage of Labor: Fetal heart rate should be monitored every $15-30\,min$.     * During the Second Stage of Labor: Fetal heart rate should be monitored every $5\,min$.     * Immediate monitoring is required after the rupture of membranes.

• Critical Thresholds:     * Normal FHR: $110-160\,bpm$.     * Fetal Distress: A change of $\pm 30\,bpm$ indicates fetal distress and must be reported immediately.

Rationale for Fetal Monitoring

• Stress Detection: Monitoring is performed to detect signs that the fetus is not tolerating the stress of labor, specifically regarding fetal oxygenation.

• Oxygen Interruption: All significant decelerations in heart rate indicate an interruption in oxygen delivery.

• Hypoxemia to Hypoxia: Oxygen interruption can result in hypoxemia, which can subsequently lead to hypoxia.

• Metabolic Acidosis: If hypoxia persists, it can lead to metabolic acidosis. This condition is clinically represented by minimal or absent variability and absent accelerations on the fetal monitor.

• Brain Protection: Proper monitoring and subsequent interventions protect the fetal brain by ensuring that hypoxia and acidosis do not occur.

Electronic Fetal Monitoring (EFM) Methods

• External Monitoring:     * Intermittent: Uses an external doppler for heart rate and palpation of the uterus to assess contractions.     * Continuous: Uses a "toco" (Tocodynamometer). Sensors are strapped to the abdomen.         * Doppler: Monitors heart rate.         * Tocodynamometer: Monitors contractions.

• Internal Monitoring:     * Requires cervical dilation and rupture of membranes.     * Continuous monitoring with a spiral scalp electrode (for heart rate) and an intrauterine pressure catheter (IUPC) for contractions.     * Risk: Associated with a risk of infection.

• Interpreting the Tracing:     * Top tracing: Shows the fetal heart rate.     * Bottom tracing: Shows uterine contractions.     * Time scale: Each small square on the monitor represents $10\,seconds$.     * Assessment: The FHR is always assessed in relation to the timing of contractions.

Analysis of Fetal Heart Rate Patterns

• Baseline FHR: The average rate over a $10\,minute$ period.

• Tachycardia: A heart rate greater than $160\,bpm$.     * Causes: Prematurity, maternal fever, maternal medication, fetal activity, fetal hypoxia, or fetal infection.

• Bradycardia: A heart rate less than $110\,bpm$.     * Causes: Fetal hypoxia, maternal drugs, maternal hypotension, or uterine hyperstimulation.     * Clinical Significance: Persistent bradycardia or a persistent drop of $20\,bpm$ below the baseline may indicate umbilical cord compression or separation of the placenta.

Fetal Heart Rate Variability

• Definition: Fluctuations in the fetal heart rate over time (assessed over a $10\,minute$ window). It is the result of integrated activity between the sympathetic and parasympathetic branches of the autonomic nervous system.

• Significance: It reflects the oxygenation of the central nervous system and reliably predicts the absence of ongoing hypoxic injury and metabolic acidemia at the time of observation.

• Categories of Variability:     * Absent: Fluctuations are undetectable.     * Minimal: Fluctuation range is less than $5\,bpm$. Causes include the fetus sleeping, prematurity, or reactions to medications.     * Moderate: Fluctuation range is between $6\,bpm$ and $25\,bpm$ (stated as range of >5\,bpm). This is normal and indicates the fetus is well-developed and oxygenated.     * Marked: Fluctuation range is greater than $25\,bpm$.

• Sign of Distress: Persistent absence or minimal variability is the most significant sign of fetal distress.     * Possible causes: Fetal metabolic acidosis, fetal sleep cycles, prematurity, congenital anomalies, central nervous system depressants, and Betamethasone.

Accelerations and Decelerations

• Accelerations:     * Elevation of FHR greater than $15\,bpm$ over baseline.     * Must last more than $15\,seconds$ and less than $10\,minutes$.     * Clinical Significance: Normal and considered reassuring.

• Decelerations (Transient fall in FHR related to contractions):     * Early Decelerations: Caused by Head Compression (HC).         * Characterized by a gradual decrease synchronized with the contraction (a "mirror image").         * The lowest point (nadir) occurs at the peak of the contraction (referred to as a "kiss").         * Action: Evaluate fetal station, maternal dilation, and effacement. No medical intervention is needed.     * Late Decelerations: Caused by Uteroplacental Insufficiency (UPI) or diminished placental function.         * Characterized by a smooth, symmetrical decrease.         * The lowest heart rate occurs after the peak of the contraction.         * Action: Execute all interventions immediately.     * Variable Decelerations: Indicates Cord Compression (CC).         * Abrupt decrease in heart rate in a $U$, $V$, or $M$ shape.         * Can occur at any time (before, during, or after contractions).         * Clinical Significance: Ominous if they are repetitive, prolonged, severe, or show a slow return to baseline.         * Action: May be relieved by changing the mother's position ("float the baby off the cord") or amnioinfusion.

The VEAL CHOP MINE Mnemonic

• Vvariable Deceleration - Cord Compression - Move mother.

• Eearly Deceleration - Head Compression - Intervention not needed (assess labor progress).

• Acceleration - Ok - None needed.

• Late Deceleration - Placental Insufficiency - Execute interventions.     * Intervention List for Late Decelerations:         1. Reposition the mother to the Left side ("Left is always Right").         2. Stop Pitocin (Oxytocin).         3. Administer IV fluids.         4. Give Oxygen ($O_2$).         5. Possible Cesarean Section ($C/S$) if the pattern persists.

Indicators of Fetal Distress and Hypoxia

• Patterns:     * Non-reassuring FHR patterns.     * Progressive increase or decrease in baseline heart rate.     * Progressive decrease in baseline variability.     * Tachycardia (>160\,bpm) or severe bradycardia (<100\,bpm).     * Persistent late decelerations.     * Severe variable decelerations with slow return to baseline.

• Amniotic Fluid Appearance:     * Normal: Pale, straw-colored, with white flecks.     * Abnormal (Meconium Staining): Pea-green, brown, yellow, or port-wine color.

Response of the Newborn to Birth

• Respirations:     * Surfactant permits the inflation of alveoli.     * The airway must be cleared (wipe vs. suction).     * A bulb syringe must be kept with the newborn at all times.     * Positioning: "Back to sleep."

• Warmth:     * Temperature drops from $99^{\circ}$ in the womb to a standard room temperature such as $70^{\circ}$.     * The infant must be dried.     * Placement: Skin-to-skin on the mother (the "best place to be") or in a radiant warmer.

• Identification:     * Identification bands for the mother, newborn, and significant other.     * Footprinting.     * Electronic security: HUGS or Totguard clamps.

Questions & Discussion

• Question 1: The provided EFM strip shows a gradual decrease in fetal heart rate that perfectly mirrors the uterine contraction, with the nadir occurring at the peak of the contraction. What are these?     * Answer: Early Decelerations.

• Question 2: What are the nursing interventions for the previous EFM strip (Early Decelerations)?     * Choices: a. Reposition mother, b. Increase IV fluids, c. Administer Oxygen, d. Continue to monitor.     * Answer: d. Continue to monitor. These are normal and expected fetal heart rate tracings.

• Question 3: When planning care for a woman whose membranes have ruptured, the nurse recognizes that the woman’s risk for what has increased?     * Choices: a. Intrauterine infection, b. Hemorrhage, c. Precipitous labor, d. Supine hypotension.     * Answer: a. Intrauterine infection. Rupture of membranes (ROM) leads to increased risk of infection due to the loss of protection from external microbes.

Nursing Process for Normal Labor

• Initial History Assessment:     * Last Menstrual Period (LMP).     * Estimated Date of Delivery (EDD).     * Labor pain characteristics.     * Presence of bleeding.     * Rupture of Membranes (ROM) status.     * Fetal movement.     * Maternal diseases and current medications.     * Last food intake.     * Birth plan, support person, and participation in childbirth classes.     * Cultural assessment and psychosocial reaction to labor.

• Physical and Laboratory Assessment:     * Vital signs, allergies, skin/falls/pain assessment.     * Labs: CBC, blood type, urinalysis, Group B strep (rapid) screen.     * Leopold’s maneuver to determine fetal position.     * Auscultation of FHR and palpation of the fundus.     * Vaginal Exam: Assesses changes to the cervix (dilation/effacement), membranes, and discharge. This provides the most valuable information about labor status.     * Vaginal Drainage: Moderate discharge is common; linen changes should be regular. Report any bright red bleeding immediately.

• Identified Patient Problems:     * Anxiousness and fearfulness.     * Impaired coping.     * Lethargy or malaise.     * Potential for: Inadequate fluid volume, infection, or injury.

Medical Interventions: Induction of Labor

• Maternal Indications: ROM >24\,hrs, Pregnancy-Induced Hypertension (PIH), Diabetes Mellitus (DM), stillbirth/fetal demise, or post-dates pregnancy.

• Fetal Indications: Intra Uterine Growth Restriction (IUGR), non-reassuring fetal status, or oligohydramnios.

• Contraindications: Active herpes infection, placenta previa, malpresentation, unexplained bleeding, or (possibly) a history of cesarean section.

• Bishop Scoring: Used to assess the readiness of the cervix for induction. A score of $5+$ is desired (See Table 11.1).

• Induction Methods:     * Amniotomy: Artificial Rupture of Membranes (AROM) to facilitate contractions. Interventions include monitoring FHR before/after, assessing fluid color/amount, and monitoring maternal temperature.     * Cervical Ripening:         * Prostaglandin gel or crushed misoprostol tablet applied to the cervix.         * Foley balloon catheter ($16F$ transcervical catheter) inserted to or past the cervical os; the balloon is filled with $30-50\,ml$.

Oxytocin (Pitocin) Management

• Purpose: To induce labor or augment labor (make contractions stronger).

• Administration: The dose is titrated to contractions and requires close monitoring of both mother and baby.

• Risks: Overstimulation of the uterus, uterine rupture, and fetal distress.

• Discontinuation Criteria: Stop the infusion and notify the Health Care Provider (HCP) if:     * Contractions are less than $2\,min$ apart.     * Contractions last more than $90\,sec$.     * Intrauterine Pressure Catheter (IUPC) shows intensity greater than $90\,mm\,HG$.     * IUPC shows a resting tone greater than $20\,mm\,HG$.     * There is no uterine relaxation between contractions.     * Non-reassuring FHR occurs.

Assisted Vaginal Birth

• Indications: Maternal exhaustion, inadequate maternal expulsive efforts, fetal distress/non-reassuring FHR, or a prolonged second stage of labor.

• Forceps Delivery:     * Spoon-like device applied to the fetal head.     * Risks to Baby: Bruising, edema, or brachial plexus injury.     * Risks to Mother: Lacerations, hematomas, episiotomy, bleeding, or prolapse.

• Vacuum Extraction:     * Vacuum cup applied to the fetal head using negative pressure.     * Risks to Mother: Lacerations.     * Risks to Baby: Cephalohematoma, bruising, or laceration.

Cesarean Section (C/S)

• Prevalence: Accounts for more than $30\%$ of deliveries.

• Classification: Scheduled or emergency major surgery.

• Reasons for C-section:     * Labor dystocia.     * Fetal distress.     * Malpresentation, Cephalopelvic Disproportion (CPD), or macrosomia.     * Multiple gestations.     * Active HSV (Herpes Simplex Virus) outbreak.     * Obstetrical emergencies.

TOLAC and VBAC

• Trial of Labor After Cesarean (TOLAC):     * The patient is allowed to have a normal spontaneous labor.     * Requires close monitoring for uterine rupture.     * The medical team must be on call for immediate cesarean delivery.

• Vaginal Birth After Cesarean (VBAC):     * Major Complication: Uterine rupture.     * Assessment/Reporting Signs of Rupture:         * Acute abdominal pain.         * Client reporting a "popping" sensation.         * Palpating fetal parts outside of the uterus.         * Repetitive or prolonged FHR decelerations.         * Vaginal bleeding.

• Decision Basis: The type of uterine incision used in the previous C-section drives the decision for TOLAC/VBAC status.