Lecture 3: Labor Flashcards
What are the components of a cervical exam?
- Dilation: How open internal os is. 10cm or more = complete
- Effacement: length of cervix (thickness/difference between internal and external os)
- Station: Degree of descent of presenting part of fetus (cm from ischial spine, measured in 3rds)
- Consistency: More firm = not in labor
- Position: anterior, mid anterior, posterior
What is required to dx labor?
Cervical change.
Contractions without changes = braxton hicks
What is the Bishop score?
Favorability of cervix for labor, determined via cervical exam results
> 8 score = favorable
What are the 4 ways to check membrane status during labor?
- Ferning
- Nitrazine paper on fluid
- Presence of pooling/cervical leakage during valsalva
- AFI (amniotic fluid index)
When is GBS screened for and how is it treated if positive?
- Screened at 35 weeks for all women.
- PCN (erythro/clinda or vanco)
C&S determines erythro vs vanco
Common cause of neonatal sepsis
Why are IV pain meds generally avoided in labor?
Can cause nonreassuring fetal status and respiratory distress
Where is an epidural given in labor? What are the complications and contraindications?
- Placed in the L3-L4 space
- Complications: maternal hypotension, respiratory depression, or spinal HA
- Contraindications: Maternal bleeding disorder or use of LMWH within 12h, or refusal
When is spinal anesthesia primarily used?
C-section
When is a pudendal block utilized in labor?
- Operative vaginal delivery
- Extensive perineal repair post delivery
When is general anesthesia utilized for labor?
Emergent/urgent settings, as the fetus gets anesthetized too.
What bishop score correlates with a poor result in induced labor?
< 5 is generally 50% failure
However, cervical ripening can help
What drug class is used for cervical ripening and why?
PGE1 (cervidil) & PGE2 (cytotec), which cause dissoution of collagen bundles and increase water uptake.
Prostaglandin
SEs and CIs of cervidil (PGE1) & Cytotec (PGE2)
- SEs: Tachysystole, Fever, V/D, uterine rupture
- CIs: Hx of C-section, myomectomy, hysterotomy
What is pitocin?
IV equivalent of oxytocin
SEs and contraindications of pitocin?
- SEs: tachysystole, uterine rupture (rarer than PGEs), HypoN, Hypotension, amniotic fluid embolism
- CI: fetal distress, HSR
What are the mechanical methods for inducing labor?
- Balloon catheter (cook)
- Laminaria (seawood to pull out water and dilate cervix)
- Amnio hook to puncture sac (better if multipara)
Balloon catheter + pitocin = good combo
What drug is typically used to augment labor?
Pitocin
What are the two ways operative vaginal delivery is done?
- Forceps
- Vacuum
When is operative vaginal delivery indicated?
- Prolonged 2nd stage of labor
- Maternal exhaustion
- Hasten delivery to prevent fetal compromise
What are the 4 stages of labor?
- Onset of labor to complete cervical dilation
- Complete cervical dilation to expulsion of fetus
- Delivery of infant to delivery of placenta
- Delivery of placenta to 1 hour postpartum
When it comes to spontaneous labor, is primip or multip quicker?
Multipara becomes quicker once the cervix is dilated 6cm.
What phase of labor is prolonged if labor has to be induced?
Latent phase
What are the 2 phases in stage 1 of labor?
- Latent phase, 0cm to 6cm (slow)
- Active (6cm to complete)
Stage 1 lasts 6-8 hours for multips, 10-12 for primips
What are the factors that affect the active stage of labor?
- Power: uterus
- Passenger: fetus
- Pelvis: opening the fetus comes out of
3 P’s
How can uterine contraction force be measured?
IUPC (Intrauterine pressure catheter) or via external tocodynamometry
What is considered adequate labor?
- 3-5 contractions in a 10 minute period
- > 200 montevideo units in a 10 minute period