Labor Flashcards
Phase 1 Parturition
Quiescence
- contractile unresponsiveness
- cervical softening
Phase 2 Parturition
Activation
- Uterine preparedness for labor
- Cervical Ripening
Phase 3 Parturition
Stimulation
- uterine contraction
- cervical dilation
- Fetal and placenta expulsion
Phase 4 parturition
Involution
- uterine involution
- cervical repair
- breastfeeding
Three Stages of Labor
First Stage = closed to 10 cm
Second Stage = 10 cm to delivery of the fetus
Third Stage = delivery of fetus to delivery of placenta
Cardinal Movements of Labor
- Engagement
- Descent
- Flexion
- Internal Rotation
- Extension
- External Rotation
- Expulsion
Classic female pelvic shape
Most Common
Gynecoid
A/P triangles are roughly even
Excellent candidate for NSVD
Least favorable pelvic shape for vaginal delivery
Android
Anterior triangle much bigger, heart shaped, prominent Sacrosciatic notch
Highly associated with arrest of first stage
Head difficult to get into pelvis
Pelvic shape associated with OP position
Anthropoid
15%
Anterior triangle bigger than posterior, narrow AP diameter
Associated with arrest in first or second stage
Least common pelvic shape
Associated with transverse arrest
Platypelloid Pelvis
A/P triangles are equal, but short AP diameter
Wide transverse axis of the pelvic inlet readily accommodates the occipitofrontal diameter of the fetal head as it descends in the pelvis - results in OT position
Pinard Maneuver - Breech extraction
Delivery of fetal legs
Two fingers are used to palpate down the fetal thigh until the knee is felt and flexed. The thigh is then moved away from midline after knee flexion is performed. Traction is then employed to deliver the foot
Loveset Maneuver Breech Extraction
Resolution of Nuchal Arm
Identify the anterior fetal arm and then gently flex the fetal elbow and attempt to sweep the arm down past the fetal face and out
Prague Maneuver Breech Extraction
Support shoulders and legs for flexion and subsequent delivery of fetal head
Two fingers of one hand support the shoulders of the fetus from underneath the fetus, while the other hand brings the fetal legs above and over the maternal abdomen.
Mauriceau-Smellie-Veit Maneuver Breech Extraction
Maxilla for flexion of fetal head
The index and middle fingers are applied to the fetal maxillae in order to flex the head during a breech delivery
Incidence of PPH for vaginal delvieries?
4%
Incidence of PPH for C/S?
6%
Timeframe for delayed PPH?
24H to 12 weeks postpartum
FHT w/ narcotics?
Decrease in accelerations
Decrease in variability
(should return to normal after 1-2 hours)
Adequate uterine contraction pattern for CST?
3 contractions in 10 minutes lasting AT LEAST 40 seconds each
Define Positive CST
Late decelerations after 50% or more of contractions (even if the contraction frequency is fewer than 3 in 10 minutes
Define Negative CST
No late or significant variable decelerations
Define Equivocal-Suspicious CST
Intermittent late decelerations or significant variable decelerations
Define Equivocal CST
Fetal heart rate decelerations that occur in the presence of contractions more frequent than every 2 minutes or lasting longer than 90 seconds
Define Unsatisfactory CST
Fewer than 3 contractions in 10 minutes or an uninterpretable tracing
Incidence of SD overall?
1.4%
Incidence of SD in pregnancies NOT affected by diabetes, but with birth weight > 4,500 g?
9-24%
Incidence of SD in pregnancies w/ diabetes + birth weight > 4,500 g?
20-50%
At what gestational age do you need 15x15 for NST?
32 weeks
Does an NST have a high or low negative predictive value?
HIGH!
Negative = no evidence of compromise
Reassuring that there is a high negative predictive value meaning low chance of disease in the fetus
Poor positive predictive value meaning even with decels, etc we don’t really know what is going on with the fetus
Components of BPP
30 mins, 10 pts (2 pts each)
- NST
- Fetal Movement (3 body or limb movements)
- Fine tone (1 episode of extension/flexion of extremity or open/close of hands)
- Breathing (1 episode of 30 seconds)
- Fluid (2x2 pocket, AFI >/= 5)
What is an equivocal BPP?
6/10
- If >/= 37w0d, consider delivery
- If < 37w, repeat BPP in 24 hours
- If repeat test = 6, delivery
- If repeat test > 6, observe and repeat per protocol
4/10 BPP?
- Typically deliver
- If same day repeat test is = 6, deliver
- If < 32w0d, additional monitoring may be appropriate
0-2/10 BPP?
- Delivery
- If delivery is not planned antenatal testing should not be performed because results will not inform management
In what order do BPP components develop? And at what gestation?
- fluid (early)
- fine tone (8wks)
- Gross movement (9 wks)
- Breathing (21 wks)
- FHT reactivity (26- 32 wks)
Loss of components is OPPOSITE of development (FHT reactivity and breathing are first to go), fluid is last
What parameter of a BPP can be BEST used to evaluate uteroplacental function?
AFI
- reflects fetal urine production, which if decreased is due to lack of renal perfusion which can be caused by placental dysfunction
Components of a modified BPP?
NST + Amniotic fluid assessment
Prolonged second stage for nulliparous
3 hr
No longer dependent on epidural status
Prolonged second stage for multiparous
2 hrs
No longer dependent on epidural
GA needed for Vacuum?
34 weeks
- less than 34w has increased risk of cephalohematoma, retinal hemorrhage, and intracranial hemorrhage