Labor and Delivery Notes

LABOR AND DELIVERY

Presenter: Melissa Dyer, PhD, RN, MSN, MBA

Critical Factors in Labor

  • The critical factors affecting labor include:
      - Birth Passage (Passageway)
      - Fetus (Passenger)
      - Relationship between Passage and Fetus (Proportion)
      - Physiologic Forces of Labor (Powers)
      - Psychological Factors (Psyche)

The Passenger

Key Aspects of Fetal Presentation

  • Considerations include fetal presentation, attitude, and head size.

Fetal Presentation

Types

  1. Cephalic (head first)

  2. Breech

  3. Shoulder

Types of Cephalic Presentation

  • A: 9.5 cm

  • B: 12.5 cm

  • C: 13.5 cm

  • The most ideal cephalic presentation for vaginal delivery is a well-flexed vertex presentation.

Common Presentations

  • The most common fetal presentations are:
      - ROA (Right Occiput Anterior)
      - ROT (Right Occiput Transverse)
      - ROP (Right Occiput Posterior)
      - LOA (Left Occiput Anterior)
      - LOT (Left Occiput Transverse)
      - LOP (Left Occiput Posterior)
      - RMA (Right Mentum Anterior)
      - RMP (Right Mentum Posterior)
      - LMA (Left Mentum Anterior)
      - LSA (Left Sacrum Anterior)
      - LSP (Left Sacrum Posterior)

Presentation Types

  • Brow Presentation

  • Facial Presentation

Types of Breech Presentation

  • A: Only 3% of pregnancies are breech.
      - Frank Breech
      - Footling Breech

Shoulder Presentation/Transverse and the Concept of Lie

  • The importance of understanding the relationship between the fetal position and axis concerning the pelvic inlet.

The Passenger - Fetal Attitude

  • Fetal attitude refers to the positioning of the fetus's body parts.
      - Ideal fetal attitude is one where the chin is flexed lower onto the chest, which optimizes the head's diameter during delivery.

The Passenger - Fetal Head Structure

  • The fetal head consists of three major parts:
      - Face: The bones are well-fused.
      - Base of Skull: Comprises two temporal bones that are well-fused.
      - Vault: Not fused, held together by sutures.
        - Sutures: Membranous spaces between cranial bones.
        - Fontanels: Intersections of cranial sutures that allow for molding of the infant's head. The anterior fontanel is diamond-shaped, and the posterior fontanel is triangle-shaped.

Passageway

Birth Passage Factors

  • Considerations affecting the birth passage include:
      - Size of Maternal Pelvis
      - Shape of Maternal Pelvis: Gynecoid shape is ideal.
      - Cervical Dilation and Effacement Capacity

Cervical Effacement & Dilation

  • Effacement: Thin, shorten, and draw up of the cervix, measured in percentages from 0% (thick) to 100% (paper-thin).

  • Dilation: Gradual opening of the cervix measured in centimeters from 0 cm to 10 cm.
      - 0% Effaced = Thick cervix
      - 100% Effaced = Paper thin cervix

Dilation Process

  • Cervix opens to allow for delivery, caused by fetal axis pressure.

  • Complete Dilation: The cervix is fully dilated to 10 cm.

Relationship of Presenting Part to Pelvis

Key Terms

  • Engagement: The largest diameter of the presenting part passes through the pelvic inlet (Biparietal Diameter - BPD).

  • Station: The relationship of the presenting part to the ischial spines, measured in centimeters.
      - Zero Station: Presenting part at ischial spines.

Station Measurement

  • Station ranges from:
      - -5 to +5, with 0 being at the ischial spines.

Forces of Labor

Contractions Details

  • Intensity: Strength of contractions.

  • Frequency: Time between the start of one contraction to the start of the next.

  • Duration: Time from the start of the contraction to relaxation phase.

  • Pushing: Engaging the abdominal muscles with contractions.

Premonitory Signs of Labor

Key Signs

  • Lightening: Engagement of fetus in the pelvis.

  • Increase in Frequency and Duration of Contractions

  • Vaginal Bleeding: Including bloody show and mucus plug.

  • Cervical Ripening

  • Back Pain

  • Spontaneous Rupture of Membranes (ROM)

  • Sudden Burst of Energy

Rupture of Membranes (ROM)

Confirmation Methods

  • Ferning Test

  • Nitrazine Test / Amnio Indicator

True Labor vs. False Labor

True Labor Characteristics

  • Regular contractions

  • Increase in frequency, duration, and strength.

  • Progressive dilatation and effacement.

  • Discomfort typically starts in the back and radiates around the body.

False Labor Characteristics

  • Irregular contractions

  • No increase in frequency, duration, or strength.

  • Does not lead to dilatation and effacement.

  • Experiencing a "hardening" sensation.

Common Labor and Delivery Medications

  • Pitocin:
      - A chemically manufactured version of oxytocin.
      - Used to augment or induce labor.
      - Promotes increased uterine tone following delivery.

Maternal Responses to Labor

Physiological Reactions

  • Cardiovascular:
      - Increased cardiac output.
      - Increased BP during contractions.

  • Fluid and Electrolyte Balance:
      - Diaphoresis, hyperventilation, increased temperature due to muscle activity.

  • Respiratory System:
      - Increased demand for O2, mild metabolic acidosis compensated by respiratory alkalosis.

  • Renal System:
      - Increased renin and angiotensin to control uterine blood flow, bladder pushed forward and upward.

  • GI System:
      - Gastric motility reduced, gastric emptying prolonged, increased acidity of gastric contents.

  • Immune System:
      - Increased WBC (25,000 - 30,000) due to stress, decreased blood glucose.

Birth Plan Considerations

Choices and Preferences

  • Care Provider Options:
      - Certified nurse-midwife
      - Obstetrician
      - Family physician
      - Lay midwife

Birth Settings:

  • Hospital:
      - Birthing room
      - Delivery room

  • Birth Center

  • Home Birth

Sample Birth Plan Components

  • Position During Birth:
      - Side lying
      - Hands and knees
      - Kneeling

  • Support During Labor and Birth:
      - Presence of partner
      - Doula presence

  • During Labor Preferences:
      - Ambulate freely
      - Use shower if desired
      - Wear own clothes
      - Use hot tub

Additional Considerations

  • Perineal prep, enema, water birth, etc.

  • Medication preferences

  • Newborn care

  • Postpartum care plans

  

Stages of Labor and Birth

Overview

  • First Stage

  • Second Stage

  • Third Stage

  • Fourth Stage

First Stage of Labor

  • Defined from 0 cm to 10 cm dilation.

Phases Within the First Stage

  1. Early/Latent Phase
      - Starts with the onset of contractions
      - Patient can cope with pain
      - Often excited

  2. Active Phase
      - Contractions intensify
      - Increased anxiety
      - Dilation ranges from 4-7 cm and fetal descent occurs
      - Typical pattern:
        - Nullipara: 1.2 cm/hour
        - Multipara: 1.5 cm/hour

  3. Transition Phase
      - Increasing force and intensity of contractions
      - Significant anxiety present
      - Dilation may slow while descent increases
      - Duration:
        - Nullipara: less than 3 hours
        - Multipara: less than 1 hour

Second Stage of Labor

  • Defined from 10 cm to delivery.

Pushing Phase

  • Urge to push is felt

  • Duration:
      - Nullipara: Approximately 2 hours
      - Multipara: Approximately 15 minutes

Coaching During Pushing

  • Provide reassurance and encouragement

  • Use birthing bar or support methods

  • Recommend open glottis pushing instead of breath-holding

  • Crowning: Indicates impending birth

Mechanisms of Labor: Cardinal Movements

  1. Descent: Head enters the inlet due to:
       1. Pressure from amniotic fluid
       2. Pressure from the uterus
       3. Contraction of abdominal muscles
       4. Extension of fetus

  2. Flexion: Chin flexes downward onto chest due to pelvic soft tissue resistance.

  3. Internal Rotation: The occiput rotates from left to right to fit the pelvic cavity's diameter.

  4. Extension: The fetal head extends under the symphysis pubis due to pelvic floor resistance and vulva opening.

  5. Restitution: Head comes out and aligns with the back due to neck twisting as shoulders enter the pelvis.

  6. External Rotation: Head turns to one side as shoulders rotate to the anterior/posterior position.

  7. Expulsion: Anterior shoulder moves under the symphysis pubis, followed by the posterior shoulder and the rest of the body.

Delivery Process

  • The head distends with each contraction.

  • Extension occurs under the symphysis pubis to deliver the head.

  • The provider instructs the patient to push to deliver the head and shoulders.

  • Followed by birth of the body.

Lacerations and Episiotomies

Types of Lacerations

  • Perineal Laceration:
      - Vaginal tissue tears for delivery.
      - Pros: It tears at the weakest areas.
      - Cons: May be difficult to repair; risks of extending to 4th-degree lacerations.
      - Prevention: Massage/mineral oil during delivery.

Episiotomy

  • Definition: Controlled cut to enlarge the vaginal opening.
      - Pros: More controlled and cleaner repair.
      - Cons: May be unnecessary.

Third Stage of Labor

Placental Separation and Delivery

  • Begins due to increased uterine tone and decreased surface area.

  • The placenta should not be pulled on.

  • Retained Placenta: Occurs when the placenta is not delivered within 30 minutes post-delivery.

Fourth Stage

Post-Delivery Period

  • Lasts 1-4 hours after delivery.

  • Ideal for initial bonding and breastfeeding.

  • Expect drop in BP and increased pulse due to blood loss.

  • Fundus should be firm and is measured between the umbilicus and symphysis pubis.

  • Shaking may occur alongside a hypotonic bladder.

Pain Management During Labor

First Stage Pain

  • Pain experienced due to dilation and contractions.

Second Stage Pain and Delivery

  • Adaptive pain management strategies are critical.

Pain Management Strategies

  • Relaxation Techniques: Comfort measures, massage, distraction, effleurage, patterned-paced breathing, and position changes.

  • Narcotics:
      - Stadol (Butorphanol Tartrate), Nubain (Nalbuphine Hydrochloride), Demerol (Meperidine), Morphine.

  • Epidural: Local anesthetics and narcotics injected into the epidural space.

  • Spinal: Local anesthetic injected into the spinal fluid, usually for cesarean sections.

Nursing Support During Labor

  • Support such as massage, breathing techniques, and meditation is key.

Epidurals: Pros and Cons

Advantages

  • Patient remains fully awake.

  • The dosage can be adjusted.

  • Ideally maintains the urge to push.

Disadvantages

  • Skilled procedure that takes about 30 minutes.

  • Reduced control of movement below the waist.

  • Higher costs.

  • Possible side effects: hypotension, seizures (rare), meningitis (rare), arrest (rare), and spinal headaches.

Supporting a Patient with an Epidural

Requirements

  • Platelet count must be at least 100,000/mm³.

Nursing Actions

  • Fluid bolus administration

  • Monitor BP frequently, observe effects on fetus

  • Frequent repositioning to prevent pressure ulcers

  • Ensure the bladder is emptied (e.g., straight catheter every 2 hours)

Contraindications for Epidurals

  • Platelet counts less than 100,000/mm³

  • Coagulation disorders or hemorrhage

  • Severe spinal abnormalities

  • Infection

  • Uncooperative patients

Cesarean Birth

Definition

  • Surgical delivery through incisions in the abdomen and uterus.

  • Method used for over one-third of births due to various indications.

Common Indications

  • Previous cesarean section (C/S)

  • Breech presentation

  • Failure to progress

  • Fetal distress

  • Placental complications

Incisions

  • Low Transverse Abdominal Incision: Most common in non-emergent situations, allowing VBAC (Vaginal Birth After Cesarean) potential with a lower rupture risk.

Nursing Care in C/S Preparations

  • Shave prep, Foley catheter placement, SCDs, and prep for spinal anesthesia during surgery.

Post-Delivery Care

  • Encourage breastfeeding in recovery

  • Provide emotional support

  • Pain management, DVT prevention strategies (ambulation, SCDs), and diet advancements.

Fetal Monitoring

Electronic Fetal Monitoring Methods

  1. External Fetal Monitor
       - Light indicates each fetal heartbeat on a digital display of fetal heart rate (FHR).
       - The tocotransducer (Toco) monitors uterine contractions.

  2. Internal Fetal Monitor
       - Uses a catheter for scalp electrode monitoring methods.

Electronic Monitoring Benefits and Drawbacks

  • External: Good for general monitoring but may miss some details.

  • Internal: Provides precise readings; however, carries risks.

Understanding Contractions

  • Frequency: Measured from the beginning of one contraction to the beginning of the next, or peak to peak.

  • Duration: Measured from the start to the end of a contraction.

  • Intensity: Graded using palpation:
      - Mild: Nose (able to indent easily)
      - Moderate: Chin (difficult to indent)
      - Strong: Forehead (hard to indent).

Fetal Heart Rate Basics

Normal Fetal Heart Rate

  • Normal baseline heart rate is between 110-160 bpm.

  • Rates may slow with increased gestational age:
      - Tachycardia: >160 bpm
      - Bradycardia: <110 bpm

Variability as a Measure of Fetal Well-Being

  • Defined by the pattern's irregularity ( factor between sympathetic and parasympathetic systems).

  • Absent Variability: Characterized by a smooth FHR pattern, indicating potential distress; nursing interventions may be necessary.

Accelerations

  • Defined as an FHR elevation of >15 bpm lasting at least 15 seconds, indicating fetal well-being.

Decelerations in Fetal Heart Rate

Types

  1. Early Decelerations:
       - Mirroring contractions due to head compression.

  2. Late Decelerations:
       - Caused by uteroplacental insufficiency, indicating stress and hypoxia. Require interventions using the "5 Turns" method.

  3. Variable Decelerations:
       - Due to cord compression; characterized by abrupt onset and abrupt return to baseline.

Further Complications of Decelerations

  • Understand the differences in deceleration patterns:
      - Prolonged Deceleration: Drop in baseline FHR lasting longer than 2 minutes but less than 10 minutes.

Indirect Assessment Methods

  • Scalp Stimulation and Cord Blood Analysis at birth for blood gases and pH checks.

Conclusion

Summary

  • Comprehensive understanding of labor and delivery is vital, including stages, maternal responses, fetal monitoring, and potential complications to ensure safe delivery outcomes.