Labor and Delivery Flashcards

1
Q

“Engagement”

A

Positioning of the head in the lower pelvis

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2
Q

“Flexion”

A

Flexion of the head, placing the occiput in presenting position

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3
Q

“Descent”

A

Descent of the neonate through the pelvis

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4
Q

“Internal rotation”

A

Internal rotation of the vertex to maneuver past the lateral ischial spines, the major barrier that the neonate must cross

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5
Q

“Extension”

A

Extension of the head to pass beneath the maternal symphysis

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6
Q

“External rotation”

A

External rotation of the head after delivery to facilitate shoulder delivery

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7
Q

What is the clinical definition of labor?

A
  • Two things must be present:
    • Painful uterine contractions
    • Cervical dilation
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8
Q

Painful uterine contractions without cervical dilation

A

These contractons are referred to as “Braxton-Hicks” contractions, and do not represent labor since cervical dilation is not present.

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9
Q

When a pregnant woman near term is experiencing contractions, when should she come to the hospital?

A
  • If there is:
    1. Leakage of fluid
    2. Vaginal bleeding
    3. Painful contractions every 5 minutes for 1 hour
    4. Decrease in fetal movements
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10
Q

Exam components unique to obstetrics

A
  • Fetal:
    • Fetal heart tone exam
    • Fetal presentation (orientation within uterus)
  • Maternal:
    • Sterile vaginal exam
      • Cervical dilation (internal os)
      • “Effacement” (distance between internal and external os)
      • “Fetal station” (position of head relative to ischial spines)
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11
Q

Cervical dilation

A

Specifically opening of the internal os

Maximal or complete dilation is 10 cm

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12
Q

Effacement describes. . .

A

. . . the closure of the space between the internal and external cervical os

In a non-effaced cervix, this distances is about 4 cm

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13
Q

Measuring fetal station

A

Fetal station of zero is defined as having the infant’s head on par with the level of the ischial spines by palpation

+1 represents 1 cm past the ischial spines, +2 2 cm past, etc.

-1 represents 1 cm beneat the ischial spine, etc.

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14
Q

Stage 1 of labor

A
  • Divided into latent and active phases
    • Latent phase:
      • Cervical dilation <4 cm
      • Can last for days, variable length and rate of dilation
    • Active phase:
      • Cervical dilation >4 cm
      • Consistent dilation of 1.2-1.5 cm/hour
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15
Q

Stage 2 of labor

A

From complete dilation (10 cm) to delivery of the infant

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16
Q

Stage 3 of labor

A

From delivery of the infant to delivery of the placenta

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17
Q

Stage 4 of labor

A

The immediate post-partum period of approximately 2 hours post-delivery of the placenta

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18
Q

Why should women avoid eating during active labor?

A

GI motility is halted, and eating can lead to severe nausea and emesis

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19
Q

Pain at different stages in labor

A
  • During stage 1, pain results from contrations of uterus and dilation of cervix ⇒ visceral pain at levels of T10 to L1
  • During stage 2, pain results from the neonate’s passage through the vaginal canal ⇒ somatic pain at level of S2-S4
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20
Q

Treatment of choice for pain of labor

A

Epidural blockage

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21
Q

Why are opioids suboptimal for pain of labor?

A

Their sedating effects are not desirable

However, if epidural is either insufficient or contraindicated, they can still be used and are often second-line

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22
Q

The epidural trade-off

A

Epidural helps a lot with pain, but also makes labor last slightly longer

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23
Q

Stage 2 of labor lasts. . .

A

. . . 2-3 hours for a 1st-time delivery, or potentially as short as minutes for multiparous women

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24
Q

Delivery is imminent when. . .

A

. . . a half-dollar size circumference of the fetal vertex is visible in-between pushes

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25
As the infant crowns. . .
. . . **it is helpful to manually support the perineum and extension of the fetal head**
26
The optimal place for an infant after delivery
Skin-to-skin on the maternal chest
27
What is "active management" of the third stage of labor and why is it important?
* "Active management" * **Fundal massage** * **Gentle cord traction** * **IV or IM oxytocin** * Decreases the risk of post-partum hemorrhage
28
Placental separation
* Takes ~30 minutes post-delivery * There are two important signs that placental delivery is imminent: * Gush of blood * Lengthening of the umbilical cord
29
Forms of "operative delivery"
* Application of traction to fetal skull with forceps * Application of traction to fetal scalp with vacuum
30
When is operative delivery indicated?
1. Prolonged or arrested stage 2 labor 2. Suspicion of immediate or potential fetal compromise 3. Shortening of the second stage for maternal benefit
31
"Obstetric conjugate"
Measurement approximated by clinical pelvimetry Essentially, this is **the narrowest fixed distance through which the neonate must pass** in order to be delivered. It should be at least 11 cm to ensure that delivery goes smoothly. This measurement may not be made clinically due to the presence of the urinary bladder, and so it is estimated as **2 cm shorter than the diagonal conjugate (which is the distance between the top of S1 and the pubic symphysis).** So, in other words, you want the **diagonal conjugate to be at least 13 cm.**
32
Pudendal nerve block
Often necessary in obstetrics, especially when there is no time for a spinal block Find the ischial spine and position the needle 1 cm inferiorly and medially. Aspirate to ensure that you are not injecting into the pudendal artery or inferior gluteal artery, which are in close approximation. Once you have confirmed this, inject lidocaine here.
33
The most feared complication of post-partum hemorrhage
Shock and disseminated intravascular coagulation
34
Coagulability in pregnancy
Pregnancy is a **hypercoagulable state.** There is an increase in the concentrations of major clotting factors and a decrease in the concentration of anti-clotting factors like protein S and antithrombin. This is evolutionarily to prevent excessive postpartum blood loss. Factors normally return to normal levels 6-12 wks postpartum.
35
Complications of DIC in pregnancy
* Abruption/fetal demise * Amniotic fluid embolism * Preeclampsia/HELLP syndrome * Postpartum hemorrhage
36
What blood products are safe to give to DIC patients?
* **Generally:** * RBCs * Platelets if \<50,000 * **If active bleeding with risk of severe shock: (in other words, risk of shock outweighs risk of thrombosis)** * Cryporecipitate (fibrinogen, VWF/Factor VIII complex, Factor XIII) * FFP (All clotting factors)
37
Ideal position of infant for delivery
Head flexed, facing the sacrum. Extension of head once past sacrum.
38
Important structures for pelvic inlet and outlet
* Inlet: Sacram promontory and pelvic brim * Outlet: Ischial spines and coccys
39
Grading of vulvar lacerations
* **Grade 1:** Simple **superficial epithelial** tear -- does not require surgical repair unless bleeding actively * **Grade 2:** Involves muscle (**bulbocarvernosus**) -- indicates surgical repair * **Grade 3:** Into and through the **external anal sphincter**, with without going to the rectal mucosa -- immediate repair * **Grade 4:** Into and through the external anal sphincter AND involving the **rectal mucosa** - immediate repair
40
Best way to prevent grade 3 and 4 vulvar lacerations
* STOPPING any routine surgical interventions of the vulva, which were previously thought to help with delivery * **"Episiotomy"**
41
What can happen if you don't quickly repair a fourth degree vulvar tear?
A recto-vaginal fistula can form, sometimes within 24 hours
42
Use of multiple tocolytics increases the risk of ___ during labor
Use of multiple tocolytics increases the risk of **pulmonary edema** during labor
43
Most common tocolytics
**Magnesium sulfate (in specific cases, shown to be less effective than others)** **Nifedipine** **Indomethacin** **Terbutaline** **Ritodine**
44
Phases of parturition
* Phase 1: Quiescence * From conception to initiation of parturition * Myometrial contractility is suspended by progesterone, prostacyclin, relaxin, and nitric oxide * Phase 2: Activation * Lasts from initiation of parturition to onset of labor * Cervical lining softens and prepares for labor via mucosal and glandular hyperplasia, collagen cross-linking is removed, uterine oxytocin receptor expression changes -- mediated by estrogen, progesterone, uterine stretch, changes in proteoglycan composition * Phase 3: Stimulation * Onset of labor to delivery * Fetus and placenta produce CRH, triggering ACTH production in fetal pituitary, and cortisol and DHEAS production in fetal kidneys. These in turn increase estrogens, prostaglandins, progesterones, and oxytocins. In the mother, oxytocin rises and binds to oxytocin receptors on the myometrium, increasing prostaglandin levels and stretch receptor # and sensitivity, stimulating **regular** uterine contractions * Phase 4: Involution * From delivery to restoration of fertility * Return to pre-pregnancy physiology and anatomy, mediated by oxytocin
45
Pathology in stage 3 of parturition may lead to. . .
. . . **pre-term labor, labor dystocia, post-term pregnancies**
46
Sources of maternal oxytocin
Posterior pituitary Decidua Extraembryonic and placental fetal tissue
47
Reducing the risk of preterm labor in someone with a history of preterm labor
**Weekly injection of 250 mg of 17-hydroxyprogesterone caproate from weeks 16-36 gestation** reduces the risk of pre-term labor This is because progesterones maintain uterine quiescence in the third trimester by limiting the production of pro-labor prostaglandins and inhibiting downstream effects of prostaglandin and oxytocin receptors. Labor is associated with functional withdrawal of progesterone in the uterus.
48
Oxytocin pharmacokinetics
Biologic halflife: 3-4 minutes Circulatory halflife: 10-12 minutes Length of uterine effects: 20-40 minutes
49
Ideally during delivery, the uterus should contract __ times in a 10 minute period.
Ideally during delivery, the uterus should contract **3** times in a 10 minute period.
50
Rate of cervical dilation in nulliparous vs multiparous women in active labor (cervix dilated \>4 cm)
* Nulliparous: 1.2 cm/hr * Multiparous: 1.5 cm/hr
51
If a woman in active labor is not meeting our expectations for normal rate of cervical dilation, what are the next steps in management?
* We want to assess the strength of the uterine contractions, starting with an **intrauterine pressure catheter** * This procudes a graph where contraction strength is measured in **Montevideo** **units,** the sum of the maximal amplitude from baseline times the number of waves over a 10 minute period * **Normal progress** is usually associated with **\>200 Montevideo units** * If contractions are deemed not strong enough, augmentation may be performed by **amniotomy** (which stimulates **prostaglandin release**) or **IV oxytocin**
52
Bony landmarks of the infantile vertex
53
We describe the position of the infant being delivered in relation to the. . .
. . . **infantile occiput and maternal pubic symphysis**
54
The optimal infantile head orientation for delivery
Occiput against the female pubic symphysis / maternal body aka the **"occiput anterior"** position
55
Most common cephalic orientations of delivery
* Occiput anterior * Occiput posterior * Occipit transverse * Compound presentation * Face presentation * All positions have increased risk of labor dystocia relative to occiput anterior
56
Arrest of dilation vs arrest of descent
Arrest of dilation: Mother does not dilate fully to 10 cm Arrest of descent: Mother dilates fully, but infant does not descend
57
Uterine tachysystole
Defined as **\>5 uterine contractions / 10 minutes over 30 minute period** Potential **complication of giving IV oxytocin** for labor dystocia due to insufficient uterine contraction
58
Shoulder dystocia management
* Form of **obstetric emergency** * When the **infant's anterior shoulder is caught behind the pubic symphysis** during stage 2 labor * In these cases, there is about **5 minutes** to delivery a well-oxygenated term infant * Management: * Ensure adequate staff * **McRobert's maneuver** (hyperflexion and abduction of hips) to open space for shoulder * **Apply suprapubic pressure** * If the above does not work, attempt **manual delivery the posterior arm** of the fetus. Episiotomy may be required here to open space posteriorly. * **Woodscrew-Rubin manevuer** may be useful (rotation of infant to reduce the shoulder) * Intentional clavicular fracture * Zavenelli procedure: Push the baby back in, do a cesarean instead
59
Shoulder dystocia brachial plexus injury
Rate ranges from 4-40% regardless of interventions performed
60
Cord prolapse
* Form of **obstetric emergency** * Cord descends in advance of the fetal presenting part and blood vessels in the umbilical cord are compressed during delivery * Often occurs with **non-vertex orientation** or **premature rupture of membranes** * Management: * Push the fetal head up so it does not further compress the umbilical cord * Manually reduce the cord back into the uterine cavity * Perform a cesarean section emergently **with the hand still in place until the baby is delivered**
61
Breech delivery
* Form of **obstetric emergency** * Singleton breech should be delivered by cesarean section, however there may be situations where this is not an option * Non operative management: * Call for assistance * Avoid traction on fetus and fetal head extension * **Wait until fetus is delivered to the level of the umbilicus, then apply suprapubic pressure to promote fetal head flexion.**
62
Schedule cesarean sections should be performed at \_\_\_
Schedule cesarean sections should be performed at **39 weeks**
63
Trial of labor after cesarean section and risk of uterine rupture
* Considering labor after previous cesarean section is a balance of risks and benefits * Vaginal delivery carries lower risk for future maternal complications, future abnormal placentation, and infantile long-term complications * However, it also carries risk of uterine rupture (~1% after one lower transverse cesarean, ~2% after two lower transverse cesareans, and 10% after just one classical cesarean section) * Hence, while women with LTCS can trial vaginal delivery, **women with classical CS should not**
64
Factors that increase the chance of successful vaginal birth after cesarean delivery
* History of prior vaginal birth * Spontaneous labor
65
Oligohydramnios effects on fetus
* Low amniotic fluid can lead to compression of the umbilical cord and **decreased placental flow** * Persistent oligohydramnios at \<22 wks eGA leads to **pulmonary hypoplasia** * **Fetal deformations** and **limb contractures** due to poor ability of fetus to move freely within amniotic sac
66
PROM vs PPROM
* PROM: Premature rupture of membranes (before the onset of labor) * PPROM: Pre-term premature rupture of membranes (before onset of labor AND before 37 weeks eGA)
67
Risk factors for premature rupture of membranes
* Ascending vaginal infections (STIs, bacterial vaginosis) * Short cervical length * Polyhydramnios (amniotic distension) * Multiple gestations (amniotic distension) * Smoking * Prior PROM * Prior pre-term delivery * Bleeding during pregnancy * Low BMI
68
Presentation of premature rupture of membranes (history and characteristic test results)
May be characterized by a **spontaneous gush of vaginal fluid**, or a **steady trickle of vaginal fluid** **Nitrazine paper** can be used on a sample to determine whether or not it is alkaline **(amniotic fluid has a pH \> 7.1** while vaginal secretions have a pH of 4.5-6 in healthy women). **Alkaline fluid will appear blue on nitrazine paper.** **"Ferning"** on dried microscope slide (dendritic crystallization pattern of amniotic fluid) **"Pooling" sign:** Filling of the speculum with amniotic fluid during speculum exam
69
Physical exam for PROM
* Sterile speculum exam with testing for chlamydia, gonorrhea, and GBS * Ultrasound to assess fetal position and amount of amniotic fluid * No digital examination / bimanual exam unless absolutely necessary (decreases risk of infection) *
70
Management of premature rupture of membranes
* **Expectant management:** * If patient is **term (\>37 weeks)**, ~90% of patients with PROM will go into spontaneous labor within 24 hours, so expectant management is reasonable. * If the patient does not go into labor within those 24 hours, induced labor should be performed with oxytocin. * If the patient is **early pre-term (24-33+6)**, the risks of prematurity outweigh the risk of infection, and corticosteroids and antibiotics are administered. Here, antibiotics have been shown to increase the amount of time before spontaneous labor, NOT to treat infection. Admit for inpatient hospitalization with regular ultrasounds and antepartum testing, Induce delivery between 32-34 weeks unless there are signs of infection. * **Immediate delivery:** * If the patient is **late pre-term (34-36+6)**, the risks of infection outweight the risks of prematurity, and induction of labor is started once rupture of membranes is performed. If infant is breech, cesarean section is performed. * If the patient is **early pre-term and there are signs of infection** (fever, uterine tenderness, increased WBC), immediate delivery must be performed.
71
Leading causes of morbidity and mortality for pre-term infants
* Respiratory distress * Infection * Intraventricular hemorrhage
72
Pre-term birth
Delivery between 20 and 37 weeks eGA
73
Risk factors for pre-term birth
* History of pre-term delivery * Short cervical length (\>2.5 cm) * Hx of cervical surgery (including LEEP/conization) * Vaginal bleeding * UTI * genital tract infections * Periodontal diseases * Low maternal BMI * Smoking * Alcohol * Short interpregnancy interval
74
Why is magnesium sulfate preferred as a short-term tocolytic for pre-term infants eGA 24-34 weeks if delivery is believed to be imminent?
This has been shown to **reduce the risk of cerebral palsy** in pre-term infants in this eGA category
75
Four classes of tocolytics
76
Tocolytics vs progesterone therapy in preterm delivery
Tocolytics are **short-term, temporizing agents** that can be used to delay delivery **up to 48 hours** Progesterone therapy (ie, **17-hydroxyprogesterone**), can actually **extend the length of the pregnancy** significantly and allow for greater fetal maturity at the time of delivery.
77
Major categories of women who should receive 17-hydroxyprogesterone therapy during pregnancy (weeks 16-36) to reduce the risk of preterm delivery
1. History of preterm birth 2. Short cervix during pregnancy (\>2.5cm)
78
Management of pre-term labor
* 24-34 weeks eGA: * Corticosteroids * 48 hours of tocolytic therapy (magnesium sulfate preferred if \<32 weeks eGA) * 34-36 + 6 weeks eGA:
79
Risk factors for cervical insufficiency
1. Hx of cone biopsy or LEEP (cervical trauma) 2. Hx of 2nd trimester miscarriage 3. Pervious early premature delivery 4. Cervical shortening prior to 24 weeks eGA
80
17-OHP in cervical insufficiency
No evidence that it helps this population when added to cerclage therapy
81
Definition of arrested active delivery
2 hours in active labor without dilation progression
82
"Clinically adequate" uterine contractility
Every ~2-3 minutes lasting for 40-60 seconds (w/ Montevideo units \> 200)
83
Traction should NOT be applied to the cord until all of the following signs have been observed:
* Gush of blood * Lengthening of the cord * Globular and firm shape of uterus * Uterus rises to the anterior abdominal wall * Otherwise, you may induce **uterine inversion**! This in turn is a risk factor for **massive post-partum hemorrhage.** **Even with optimal treatment, hemorrhage is almost a certainty in uterine inversion.** * Grand multiparity and placenta accreta are also risk factors.
84
Managing uterine inversion during placental delivery
* Two IV lines should be started immediately in the event of hemorrhage * Uterine relaxing agent is essential (often halothane, sometimes tertbutaline or magnesium sulfate) * If placenta fully separated, uterus may be replaced with a gloved hand * Once uterus is in place, oxytocin is given to restore uterine tone
85
Erb's palsy
Most common brachial plexus injury result of shoulder dystocia. Injury to the C5-C6 roots specifically.
86
McRobert's maneuver
1. Hyperflexion of maternal hip onto maternal abdomen 2. Suprapubic pressure
87
Specific risks for shoulder dystocia
1. Fetal macrosomia 2. Maternal diabetes (gestational or otherwise) 3. Maternal obesity 4. Prolonged second stage of labor
88
Why is diabetes an independent risk factor for shoulder dystocia?
Diabetes physiology in the fetus promotes central adiposity, increasing the shoulder girth
89
What maneuver should you *not* perform during a shoulder dystocia delivery?
Fundal pressure This increases the risk of injury to the neonate
90
A woman comes in for delivery at term and is in labor with cervical dilation at 5 cm, but membranes have not yet ruptured and the infant is at -3 cm station (unengaged). Artificial rupture of membranes is performed. But, after this is performed, the fetal heart rate decreases to 80 bpm for three minutes. What is the next step?
**Evaluate for cord prolapse** This is a classic scenario for cord prolapse. The fetal head is usually what stops the cord from prolapsing -- if it is unengaged at the time of rupture of membranes, cord prolapse is likely to occur. This is why, as a general rule, **artificial rupture of membranes should not be performed with an unengaged fetal part** In any case, for this patient, once the cord is palpated on vaginal exam the diagnosis is confirmed and they should be taken for **immediate Cesarean section.** At this time **oxytocin should also be stopped**.
91
Positioning the patient in cord prolapse to avoid pressure on the cord
Patient should be in Trendelenburg position (head down) and physician should keep his or her hand in the vagina to elevate the presenting part and keep pressure off of the cord (like a Zavanelli maneuver)
92
\_\_ of women will delivery witihn 1 week of PPROM
**50%** of women will delivery witihn 1 week of PPROM
93
Role of antibiotics in PPROM
Buying time for betamethasone!!! We aren't looking to keep mom pregnant forever, but just long enough to do our interventions protecting against risks of prematurity
94
Three things you are worried about with PPROM
1. Chorioamnionitis 2. Preterm labor 3. Placental abruption
95
Fetal fibronectin assay
If pre-term labor is suspected, then prior to digital exam a swave may be uesd to sample the posterior fornix for fetal fibronectin. If present, this indicates likelihood of imminent preterm delivery. If negative, there is unlikely to be delivery for at least one week.
96
Common triggers of preterm labor
* UTI * Cervical infection * Bacterial vaginosis * Generalized infection * Trauma * Abruption * Hydramnios * Multiple gestations
97
Clinical diagnosis of preterm labor in a primigravid individual
* **Cervical dilation \> 2 cm with \>80% effacement** are sufficient in this population * However, if the individual is already parous or multiparous, this is not reliable.
98
Cervical length and features on ultrasound associated with increased risk of pre-term delivery
\<25 mm "Funneling" observed on US (amnion extending slightly in a cone shape into the cervix) also increases the risk.
99
Complication associated with use of indomethacin as a tocolytic
Can increase the risk of premature ductus arteriosus closure, resulting in neonatal pulmonary hypertension in the first weeks of life.
100
How to think about steroids for anticipated preterm delivery
Given between 24 and 34 weeks EGA On the lower end (24-28 weeks) their primary role is to reduce risk of intraventricular hemorrhage in the neonate On the higher end (28-34 weeks) their primary role is to reduce the risk of respiratory distress syndrome of the newborn.
101
Indomethacin and variable deccelerations
Variable deccelerations are caused by cord compression. Risk factors for this include oligohydramnios, rupture of membranes, vasa previa, and nuchal cord. Indomethacin is often associated with oligohydramnios, which can lead to cord compressions and variable deccelerations.
102
Common complications of PROM
1. **Preterm labor** 2. **Chorioamnionitis** 3. Necrotizing enterocolitis 4. Placental abruption * bolded are most common
103
Clinical suspicion of PPROM is high, but there is no pooling of fluid on speculum exam and you cannot obtain a decent sample for nitrizine or ferning tests. What other test can you preform?
Ultrasound demonstrating oligohydramnios would be suspicious for PPROM in this case.
104
How recommendations for intramuscular corticosteroids change for premature labor with and without PROM
Without PROM: Any baby from **24 to 34 weeks EGA** gets steroids With PROM: Babies from **24 to** **32 weeks EGA** get steroids UNLESS there is evidence of **chorioamnionitis**
105
If a patient arrives already in active labor with the infant above 0 station, but with low fetal heart rate, what is the best intervention?
Attempt operative delivery with forceps or vacuum.
106
A BPP during labor is. . .
. . . **never of any value** This is often on questions **purely to be a wrong answer**
107
\_\_ are contraindicated as induction agents in patients with history of C section
**Cervical ripening agents** are contraindicated as induction agents in patients with history of C section Due to risk of uterine rupture!!! Oxytocin with careful observation is okay, but this more increases contraction strength than truly inducing labor. AROM also helps.
108
High dose oxytocin may induce __ due to its structural resemblance to \_\_
High dose oxytocin may induce **hyponatremia** due to its structural resemblance to **vasopressin**
109
Reasons for C/S vs Operative Delivery in a patient in 2nd stage arrest
* **Operative delivery:** * Faster * If high odds of success, this is the best option * Risk of ICH * **C/S:** * Slow, but less prone to possibility of procedural failure * Lower risk of ICH if station is negative * If station is positive/baby is arrested close to the perineum, risk of ICH is similar to operative deliver * **THE HIGHEST POSSIBLE RISK IS TO FAIL AN OPERATIVE DELIVERY, THEN ATTEMPT A C SECTION**
110
When should external cephalic version be performed?
37 weeks and beyond Since prior to this, fetus is likely to turn on its own
111
Past what point is misoprostol really not helpful for initiating or progressing labor?
Once the patient is ~7 cm dilated. Remember, it will help *get you to* cervical ripening, but if the cervix is basically ripe then it won't do anything.
112
Risks of a forceps delivery
* Facial nerve palsy * Increased risk of 3rd and 4th degree laceration and OASIS (Obstetric anal sphincter injury syndrome -- incontinence/loss of bowel control) * Risk of fetal cranial hematomas (benign and concerning)
113
Vitamin D is supplemented in neonates until. . .
. . . **2 months**
114
Use of high doses of pitocin increases risk of. . .
. . . **uterine hemorrhage, tachysystole, and uterine rupture (in those with prior C section)**
115
You don't want someone's membranes ruptured for more than \_\_\_\_
You don't want someone's membranes ruptured for more than **18-24 hours** They are at high risk for chorioamnionitis after this time.
116
\_\_\_ is an important and specific sign for uterine rupture
**Loss of fetal station** is an important and specific sign for uterine rupture
117
Use of amnioinfusion trial to prevent unnecessary emergent Cesarean section in oligohydamnios delivery
In a patient with oligohydramnios with recurrent variable decelerations that persist despite repositioning, amnioinfusion may be tried to see if this eliminates decelerations. This may prevent an unnecessary Cesarean delivery.
118
After rupture of membranes, ___ indicates arrest of labor in the first stage.
After rupture of membranes, **\> 4 hours of adequate uterine contractions (≥ 200 Montevideo units) and failure of the cervix to dilate past 7 cm** indicates arrest of labor in the first stage. **Cesarean delivery** is indicated at this time.
119
When do you test for markers of fetal lung maturity?
Only if you do not have an estimate of the gestational age for a fetus when mom presents in PROM. If you do know the EGA, then just follow standard guidelines for betamethasone, do not order this test.
120
Management of transverse lie presentation
* If the patient is at term and **not yet in labor,** **external cephalic version** may be attempted * If the patient is already **in active labor, Cesarean seciton** is indicated
121
Why is external cephalic version usually performed at 37 weeks for breech and transverse lie fetuses?
Two reasons: 1. They are **unlikely to change position** prior to delivery 2. This is the time when the level of **amniotic fluid is at a maximum** and **uterine tone is still optimal** for the procedure
122
Side effect of terbutaline
Sometimes terbutaline may result in **hypokalemia** due to **hyperactivation of the Na/K pump.** This will present as **fatigue, proximal muscle weakness,** and **decreased deep tendon reflexes** in a patient on terbutaline for tocolysis.
123
Role of tranexamic acid in postpartum hemorrhage
Tranexamic acid is the **last *medical* therapy** we try for postpartum hemorrage, following oxytocin, ergotamines, and prostaglandins -- however we use it before we resort to **surgical and interventional radiological procedures.** Remember, it is a **synthetic lysine analog** and **inhibitor of plasminogen with antifibrinolytic action**.
124
With a history of term abruption, induced delivery of subsequent pregnancies at ___ is indicated
With a history of term abruption, induced delivery of subsequent pregnancies at **37-38 weeks EGA** is indicated