RNC-OB study guide by content category

For a patient with chronic hypertension requiring medication, which surveillance is recommended to detect uteroplacental insufficiency?

Pick the option you would mark on test day. The choice stays fixed, and every option then explains itself.

1. Weekly uterine artery Doppler

   Weekly uterine artery Doppler is not a recommended surveillance test here; Doppler of the umbilical artery is added once growth restriction is found.
2. Serial ultrasounds for fetal growth

   Serial ultrasounds for fetal growth are recommended when chronic hypertension needs medication, because growth restriction is the main sign of uteroplacental insufficiency.
3. Daily fetal kick counts

   Daily fetal kick counts are not an established surveillance method for uteroplacental insufficiency and cannot detect slowing growth.

A patient at 31 2/7 weeks has BP 168/112 mm Hg confirmed after 15 minutes, platelets 95,000/µL (95 × 10⁹/L) and AST twice the upper limit of normal. After magnesium sulfate is started, the nurse should anticipate

1. oral labetalol and birth planned at 37 weeks

   Oral labetalol and birth planned at 37 weeks fit hypertension without severe features; severe-range readings and abnormal labs call for rapid IV treatment and earlier birth.
2. expectant care with birth planned at 34 weeks

   Expectant care with birth planned at 34 weeks is reserved for stable severe preeclampsia without laboratory abnormalities; low platelets and elevated liver enzymes allow only the delay needed for steroids.
3. IV labetalol and steroids with birth in 48 hours

   Sustained severe-range pressure needs fast-acting treatment such as IV labetalol, and a platelet count under 100,000 with doubled transaminases before 34 weeks means corticosteroids and birth after about 48 hours if mother and fetus stay stable.

Before a nonstress test, a patient asks whether drinking orange juice will make the fetus more active. The nurse explains that maternal glucose intake

1. does not improve NST reactivity

   Maternal glucose intake does not improve NST reactivity in trials, so juice or sugar before the test is not recommended for that purpose.
2. is required before every nonstress test

   Saying glucose is required before every nonstress test repeats a common myth; no fasting or sugar preparation is needed.
3. should replace vibroacoustic stimulation testing

   Vibroacoustic stimulation does shorten testing and reduce nonreactive results, so glucose is no substitute for it.

Thirty minutes after IV fentanyl, a laboring patient's tracing shows minimal variability with a normal baseline and no decelerations. The most likely cause is

1. umbilical cord compression

   Umbilical cord compression shows up as variable decelerations, which this tracing does not have.
2. fetal metabolic acidemia

   Fetal metabolic acidemia usually develops with recurrent decelerations or a changing baseline; isolated minimal variability right after an opioid points to the drug.
3. maternal opioid effect

   A maternal opioid effect, such as IV fentanyl, depresses fetal central nervous activity and lowers variability for a while, with a normal baseline and no decelerations.

A patient in preterm labor received terbutaline 0.25 mg subcutaneously 30 minutes ago. The FHR baseline is now 170 bpm, up from 140, with moderate variability. This change is best explained by

1. fetal tachyarrhythmia

   A fetal tachyarrhythmia such as SVT usually runs above 200 to 220 bpm and starts abruptly, not at 170 bpm right after a beta-agonist.
2. beta-agonist medication effect

   Terbutaline is a beta-agonist that crosses the placenta, so a rise in the fetal baseline with preserved moderate variability soon after a dose is a medication effect.
3. evolving fetal hypoxemia

   Evolving fetal hypoxemia raises the baseline gradually and usually wears down variability; an abrupt rise with moderate variability right after a beta-agonist points to the drug.

A multiparous patient at 39 weeks with ruptured membranes is in triage. The finding that indicates active labor is

1. 6 cm dilation with regular contractions

   Current ACOG guidance puts the start of active labor at 6 cm, because progress before 6 cm is often slow even in normal labor.
2. 3 cm dilation with complete effacement

   3 cm dilation with complete effacement is still latent labor; effacement does not move the active-phase threshold.
3. 4 cm dilation with regular contractions

   4 cm dilation with regular contractions was the older threshold; many patients at 4 to 5 cm are still in a slow latent phase.

Immediately after spontaneous rupture of membranes, the FHR drops abruptly from 140 to 70 bpm and stays there. The nurse's first action is to

1. perform a sterile vaginal examination

   An abrupt, sustained drop in the FHR right after membranes rupture suggests cord prolapse, so a sterile vaginal examination is done at once to feel for the cord and lift the presenting part off it.
2. document the color of the amniotic fluid

   Documenting the color of the amniotic fluid does nothing for a fetus whose cord is possibly compressed, so it comes after the examination.
3. turn the patient to a supine position

   Turning the patient to a supine position adds aortocaval compression; with a suspected prolapse the hips are raised, as in knee-chest or Trendelenburg.

In active labor, a patient has intense back pain. The abdomen looks flattened below the umbilicus, and small fetal parts are felt easily in the anterior abdomen. The nurse suspects

1. a mentum anterior face presentation

   A mentum anterior face presentation is recognized by feeling the chin and facial features at the cervix; it does not produce this abdominal picture.
2. occiput posterior position

   Intense back pain, a flattened area below the umbilicus and fetal small parts felt anteriorly fit an occiput posterior position, with the fetal back toward the maternal spine.
3. occiput anterior position

   In an occiput anterior position the fetal back lies toward the front, so the abdomen is rounded and small parts are felt posteriorly.

After a vacuum-assisted birth, a neonate has a boggy scalp swelling that crosses suture lines and is spreading toward the neck; the neonate is becoming pale and tachycardic. The nurse should suspect

1. cephalohematoma

   A cephalohematoma lies under the periosteum, so it stops at suture lines and rarely causes hemodynamic change.
2. subgaleal hemorrhage

   Subgaleal hemorrhage is bleeding beneath the scalp aponeurosis; it crosses sutures, can spread to the neck and ears and can hold enough blood to cause hypovolemic shock, especially after vacuum birth.
3. caput succedaneum

   Caput succedaneum is scalp edema that crosses sutures but does not keep enlarging or cause pallor and tachycardia.

At discharge screening, a postpartum patient reports a week of hopelessness and, on direct questioning, occasional thoughts of overdosing, with no specific plan. The nurse should arrange

1. safety measures and an urgent mental health evaluation

   Thoughts of overdosing are suicidal ideation, so the patient stays under safety measures and is evaluated urgently by a mental health clinician before any discharge decision.
2. reassurance that these are normal baby blues

   Baby blues are mild, fade within about two weeks and do not include suicidal thoughts; reassurance here misses a positive screen.
3. outpatient referral and discharge with crisis line numbers

   Outpatient referral and discharge with crisis line numbers sends the patient home before anyone has assessed her suicide risk.

On postpartum day 1 after epidural labor analgesia, a patient has a severe frontal headache that worsens when she sits up and eases when she lies flat. BP is 118/74 mm Hg. The nurse suspects

1. postpartum preeclampsia

   Postpartum preeclampsia comes with raised blood pressure, and the headache is not positional; a BP of 118/74 mm Hg argues against it.
2. post-dural puncture headache

   A frontal or occipital headache that worsens upright and eases lying flat after neuraxial analgesia is the classic post-dural puncture headache.
3. caffeine withdrawal headache

   A caffeine withdrawal headache is diffuse and does not change with posture.

The 20-week anatomy scan shows a placental edge 1.5 cm from the internal cervical os. The patient has no bleeding. The nurse anticipates

1. a repeat transvaginal ultrasound at 32 weeks

   A placental edge less than 2 cm from the os at the anatomy scan is a low-lying placenta; most move away as the lower segment grows, so a repeat transvaginal ultrasound at about 32 weeks decides the plan.
2. weekly digital cervical examinations

   Weekly digital cervical examinations add bleeding risk when the placenta is near the os and give no information about where the placenta lies.
3. a cesarean at 36 weeks regardless of later scans

   Booking a cesarean at 36 weeks regardless of later scans ignores that most low-lying placentas resolve; the mode and timing of birth wait for the follow-up scan.

After a shoulder dystocia is resolved and the baby is born, which documentation is most essential?

1. Maternal pain scores during the second stage

   Maternal pain scores during the second stage are routine labor data and say nothing about the dystocia or how it was resolved.
2. Fetal weight estimate from the last ultrasound

   A fetal weight estimate from the last ultrasound is prenatal history already in the chart; it does not describe how the emergency was managed.
3. Head-to-body interval and maneuvers

   The time from birth of the head to birth of the body and each maneuver used, in order and by whom, are the core facts of a shoulder dystocia record and the first details reviewed if an injury is later claimed.

To track efforts to safely lower its cesarean rate, a labor unit uses the national perinatal core measure for cesarean birth. That measure counts cesareans among

1. all births at 37 weeks or later on the unit

   Counting all births at 37 weeks or later mixes in breech, twin and repeat cesareans, so the rate would move with the patient mix, not with practice.
2. births to patients with a previous cesarean

   Births to patients with a previous cesarean are left out of the measure; repeat cesarean rates reflect earlier decisions and TOLAC availability rather than current labor management.
3. term singleton vertex births to nulliparas

   The core measure counts cesareans in nulliparous patients with a term, singleton, vertex fetus: the group in which a first cesarean depends most on labor practice and shapes every later birth.