Download Intrapartum Care - UNC School of Medicine

Intrapartum Care
UNC School of Medicine
Obstetrics and Gynecology Clerkship
Case Based Seminar Series
Objectives
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Review the signs and symptoms of true and false labor
Review the assessment of laboring patient
Describe stages of labor
Review pain management strategies
Review methods for monitoring mother and fetus
Review indications for operative delivery
Labor
• Labor: progressive change of the cervix in the setting of
uterine contractions
• Term Labor: > 37 weeks gestation, but < 42 weeks
• Preterm Labor: < 37 weeks gestation
» Leading direct cause of neonatal death
• The risk of mortality decreases with gestational age, but
relationship is non-linear
» 12% of all US births in 2011
• The majority late preterm
Signs and Symptoms of Labor
• Frequent, painful contractions
• “bloody show” – cervical effacement with extrusion of mucus
from endocervical glands and small amount of bleeding
• Leakage of vaginal fluid – rupture of membranes
False Labor
• Braxton Hicks Contractions
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Not associated with dilation of cervix
Shorter in duration that true labor contractions
Less intense that true labor contractions
Common late in pregnancy
• Management
» Ambulation
» Hydration
» Analgesia
Stages of Labor
• 1st stage – onset of labor until full cervical dilitation
• 2nd stage – from full dilitation to birth of infant
• 3rd stage – from birth of infant until delivery of placenta
• 4th stage – 2 hours after the delivery of placenta
Stages of Labor
• Latent phase: onset of contractions until
active phase
• Active phase: 3 cm dilation in nulliparas; 4
cm dilation in multiparas to deceleration
phase
• Deceleration phase: 8 – 9 cm dilation to
complete dilation
Exam of the laboring woman and her Fetus
• Review of prenatal records and labs
• Physical exam
» 1. Vitals and routine physical exam
» 2. Abdominal Exam
• Palpation of contractions
• Leopold’s maneuvers
» 3. Pelvic Exam
• Membranes
• Cervical status
» 4. Fetal heart rate monitoring
Review of Prenatal Records
• Past medical, surgical, obstetrical, gynecologic, social and family
histories
• Medications
• Allergies
• Routine prenatal lab work
» GBS status
• Complications of current or past pregnancies
Abdominal Exam
• Leopold maneuvers
» To assess estimated fetal weight, fetal lie, presentation and
position, attitude, and (a)synclitism
Estimating Fetal Weight
• Leopold’s maneuvers
• Ultrasound
» Estimate of fetal weight (error of 10 – 15%)
» Maternal estimate of fetal weight (best)
Fetal Lie
• Lie: relationship between the long axis of the fetus and
the mother
» Longitudinal
» Transverse
» Oblique
Fetal presentation
• Presentation: fetal part closet to pelvic inlet
» cephalic
» breech
» shoulder
Fetal Position
• Position: relationship of fetal presenting part to the
maternal pelvis
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Occiput
Brow
Mentum
Breech
Shoulder
Fetal Attitude
• The relationship of the fetal parts to one another (i.e. flexion 
extension of head relative to body).
(A)synclitism
• Synclitism is when the biparietal diameter of the fetal head is
parallel to the planes of the maternal pelvis.
Pelvic Exam
• Pelvic Exam = sterile vaginal exam +/- sterile speculum exam
• Assessing for:
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Dilation
Effacement
Station
Position of cervix
Obstetrical Pelvic Exam
• Dilation (dilatation): patency of the internal cervical os
» 0 = “closed”
» 10 cm = “complete”
• Effacement: shortening of the cervical length
» 0% = “thick”
» 100% = “fully effaced”
Obstetrical Pelvic Exam
• Station: level of presenting part (bony portion) in
relation to the maternal ischial spines
» Ischial spines = O station
» Above spines: -5 to -1
» Below spines: +1 to +5
What’s going on in there?
• The cardinal movements of labor are the mechanism by which
the fetus moves progressively through the birth canal.
Cardinal Movements of Labor
1. Engagement: descent of biparietal diameter to the
level of the ischial spines (0 station)
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Often occurs before onset of labor in nulliparous
patients
2. Descent
3. Flexion: presenting diameters of fetal head
presenting to maternal pelvis are optimized
Cardinal Movements of Labor
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Internal rotation: fetal occiput rotates from
transverse to AP
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Extension: head rotates under symphysis pubis
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External rotation (restitution): occiput and spine
assume same position
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Expulsion: fetal body delivers
3rd and 4th stages
• Delivery of placenta
• Bonding, etc
Anesthesia/Analgesia
• Cesarean section
» Spinal
» Epidural
» General (more risky in obstetrics)
• Vaginal delivery
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IV pain meds
Local
Pudendal
Epidural
Combined spinal/epidural
Pudendal Block
Lacerations
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Cervical (use clock to describe location)
Vaginal (left or right)
Periurethral
Clitoral
Perineal
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1st degree: skin only involved
2nd degree: skin and subcutaneous tissue
3rd degree: external rectal sphincter
4th degree: rectal mucosa not intact
First degree
Second degree
Third degree
External sphincter
External sphincter
Indications for Operative Vaginal Delivery
• Prolonged second stage of labor
• Non-reassuring fetal status
• Maternal cardiac or neurologic disease
» Valsalva maneuver is contraindicated or cant be performed well in
some conditions
Indications for Cesarean Delivery
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Hemorrhage from placenta previa
Placental abruption
Prolapse of umbilical cord
Uterine rupture
Breech (though vaginal delivery also a possibility)
Multiple Gestation
• The approach to delivery depends on:
» Gestational age/estimated fetal weight
» Presentation
» Experience of attending physician
• Twins
» Vertex/vertex – vaginal delivery
• 40% of all twin pairs enter labor this way
» Vertex/breech or transverse lie – external cephalic version,
breech extraction of 2nd twin, or cesarean
» Breech/other – C-section (locked twins)
• Multiple
» Cesarean delivery indicated
Bottom Line Concepts
• False labor is characterized by irregular uterine contractions
that do not lead to cervical change
• Labor management includes good communication, providing
comfort and regular assessment of both maternal and fetal
status.
• Leopold’s maneuvers and cervical examination provide
information about fetal lie, presentation and station
• After delivery of the placenta, it should be examined to make
sure it is intact