Transcript Womb To Grow - Logan Class of December 2011

“Womb To Grow”
Normal Labor & Delivery (ch 10)
Malpresentation (ch 21)
Complications of Labor & Delivery (ch 25)
Obstetric Anesthesia (ch 26)
Operative Delivery (ch 27)
Birth Experience
Presentation
Vertex (cephalic)
Breech
Transverse
Leopolds Maneuvers
Cephalic Presentation
Relationship of occiput to maternal
pelvis
Anterior fontanelle (frontal
bones/parietal bones) larger &
diamond shape
Posterior fontanelle (parietal bones &
occipital bone) smaller & triangle
shaped
Sagittal suture is midline
Asynclitism = sagittal suture not
midline
Preparations for Labor
Lightening – fetal head
settles into pelvis
Increased pelvic
pressure
Braxton Hicks
Cervical effacement
(thinning)
Bloody show
Mucous plug
Nausea/diarrhea
Let’s Talk Cervix
Dilation (closed to 10 cm)
Effacement (thinning)
Station (biparietal diameter in
relation to ischial spines)
Effacement
• Typical cervix 3-5 cm
• Subjective measurement
Station
Labor
Contractions that cause cervical
change (either effacement or
dilation)
Contractions
True Labor
Regular intervals
Increased intensity
Discomfort lower
abdomen/back
Does not stop with
walking/shower
Cervical change
False Labor
Irregular intervals
Intensity same
Discomfort lower
abdomen
Relieved with
walking/shower
No cervical change
Pain of Labor
Thinning & dilation of the cervix
Lactic acid build up as the uterus
contracts
Compression of the bladder/rectum
Stretching of the vagina &
perineum
Personal beliefs & cultural
conditioning in response to pain
Normal Labor – Stage 1
Onset of labor until completely
dilated (10 cm)
Nulliparous: average 10-12 hours
6-20 still considered normal
Multiparous: average 6-8 hours
2 to 12 still considered normal
Stage 1 – Latent Phase
Onset of labor until 3-4 cm dilation
Characterized by slow cervical
dilation
Stage 1 – Active Phase
Nulliparous: expect 1 cm/hour 
Multiparous: expect 1.2 cm/hour 
Cervical Exams
Rupture of Membranes
SROM = spontaneous rupture of
membranes
PROM = premature ROM
AROM = artificial ROM
PPROM = preterm premature ROM
Stage 2
Begins when the cervix is
completely dilated to delivery of
the infant
Nulliparous: average 50 minutes
Multiparous: average 20 minutes
Cardinal Movements of Labor
Episiotomy
Previously commonplace
Sometimes needed to hasten delivery
Relief from impending or ongoing
shoulder dystocia
Rate of 3rd & 4th degree lacerations
increased with routine use
Stage 3
Begins with delivery of the infant
until delivery of the placenta
Up to 30 minutes still considered
normal
Dystocia
Difficult labor or childbirth
•Power
•Passenger
•Pelvis
Abnormal Labor Patterns
Arrest Disorders
Arrest of dilatation – no cervical change
for > 2 hours with adequate contractions
Arrest of descent – no fetal descent
with adequate maternal effort
50% patients with arrest disorders
demonstrate fetopelvic disproportion
Precipitous Labor
Primipara >5 cm/hour dilatation
Multipara >10 cm in one hour!
(Ouch!)
Abnormalities of the Passenger
5% of all labors
Vertex malpositions
Occiput posterior
Malrotation during active phase (66% time)
Contracted pelvis (android/anthropoid)
Insufficient uterine action
Passenger
Other malpositions
Occiput transverse
Brow presentation
Face presentation
Transverse (back up/down)
Breech Presentation
Breech Presentation
At term 3-4%
32 weeks = 7%
< 28 weeks = 25%
ACOG’s formal position is that planned
vaginal delivery of breech presentation
no longer appropriate
External cephalic version
Planned cesarean section
External Cephalic Version
Fetal Macrosomia
Implies fetal growth 4000-4500 g
5% deliveries
Risk Factors
Maternal diabetes
Maternal obesity (>90 kg)
Excessive weight gain (>20 kg)
Post-date pregnancy
Previous macrosomic delivery
Male infant
Advanced maternal age
40% macrosomic infants born to patients
without identifiable risk factors
Shoulder Dystocia
Difficult delivery of the shoulders
after delivery of the fetal head
Obstetric emergency
High risk of brachial plexus injury,
hypoxia, asphyxia
Fracture of clavicle/humerus
Spinal Cord Injuries
Brachial Plexus Injuries
Erb’s Palsy
Injury to C5-C6 nerve roots
Upper limb internally rotated/flexed
wrist (Waiter’s tip)
Klumpke’s Palsy
Less common
Injury to C7-C8 nerve roots
Paralysis of intrinsic muscles of the
hand, wrist weakness
Fractures
Clavicle most frequently fractured bone
during delivery
Infant doesn’t move affected arm as
freely
Crepitus or bony irregularity
Immobilization
Remarkable callous formation within 1
week
Excellent prognosis
Cranial Molding
Over-riding of parietal bones allows
passage of vertex into pelvis
Results in caput succedaneum
Disappears within first few days of
life
Diffuse, edematous swelling of soft
tissues of scalp
Crosses suture lines
Cephalohematoma
Subperiosteal hematoma
Usually over one parietal bone
Usually results from difficult
vacuum or forceps delivery
Develops hours after birth
Occasionally associated with skull
fracture
Usually resolves spontaneously
Operative Vaginal Delivery
Prolonged second stage
Maternal exhaustion
Maternal medical conditions that
preclude pushing
Need to hasten delivery (fetal
indications)
Vaginal operative delivery rate 10-12%
Forceps vs. Vacuum
Cesarean section
Forceps
Traction +/- rotation
Cervix must be fully dilated
Membranes ruptured
Head at “0” station or below
Empty bladder
Exact position known
No significant cephalopelvic disproportion
Adequate anesthesia
Experienced operator
Forceps Application
Vacuum Extractor
Introduced in 1954
Same indications/contraindications
Only traction – no rotation
3 pop offs indicates need to move
toward c-section
Higher incidence of
cephalohematoma
Cesarean Section
Nothing to do with Julius Caesar!
First documented c-section on a living
patient 1610 (died 25 days later)
First successful C/S in the US 1794
Maternal mortality 0.01%
Past 20 years rate has risen from 5% to
>20%
Avoidance of mid-forceps/vaginal breech
delivery
Fetal heart rate monitoring in labor
Previous c-sections
Reasons for C-section
Previous c-section (most common)
Failure to progress in labor
Breech, shoulder, or compound
presentation
Placenta previa
Placental abruption
Fetal distress
Cord prolapse
Failed operative delivery
Active herpes
Types of C-section
Uterine not skin incision is what
counts
Classical
“Simplest”
Greatest blood loss
Highest risk for rupture in subsequent
pregnancies (4-9%)
Vertical incision on the uterus
Placenta previa
Transverse lie
Premature delivery
Low Transverse/Low Cervical
Much more common
Incision made transversely in low
uterine segment
Risk of rupture 0.2-1.5%
Goals for Healthy People 2010
Reduce primary C/S rate among low
risk women to 15.5%
Increase VBAC among low risk
women to 37/100 deliveries
(baseline 30/100 in 1996)
Labor Pain
First Stage
Second Stage
T10-L1 segments
Ischemia of the
uterus during
contractions
Dilation &
effacement
Distention of the
vagina & perineum
Pudendal nerve
Regional Anesthesia
Lumbar epidural block
Subarachnoid (spinal) block
Pudendal block
Have a good week off! Don’t
forget your Take Home Exam