Chapter 6 (Obstetrics): Complications of labor and delivery

Question 1

1. What is preterm labor?
2. What are the complications?
3. What are the risk factors?

Answer 1

1. Labor that occurs before week 37 is called preterm labor (PTL). Many patients present with preterm contractions, but only those who have cervical change as measured on cervical examination are diagnosed as having PTL.
2. Prematurity immediately puts infants at increased risk of respiratory distress syndrome (RDS), intraventricular hemorrhage, sepsis, and necrotizing enterocolitis.
3. These include but are not limited to preterm rupture of membranes (ROM); chorioamnionitis; multiple gestations; uterine anomalies, such as a bicornuate uterus; previous preterm delivery; maternal prepregnancy weight less than 50 kg; placental abruption; maternal disease, including preeclampsia, infections, intra-abdominal disease or surgery; substance abuse; and low socioeconomic status.

Question 2

1. What is tocolysis?
2. What are the contraindications?
3. What are the examples of tocolytics?

Answer 2

1. Tocolysis is the attempt to prevent contractions and the progression of labor. The principal goal of tocolytic therapy is to delay delivery by at least 48 hours. This is because the principal benefit is to allow treatment with steroids to enhance fetal lung maturity and reduce the risk of complications associated with preterm delivery. Betamethasone, a glucocorticoid, has been shown to reduce the incidence of RDS and other complications from preterm delivery.
2. Chorioamnionitis, nonreassuring fetal testing, and significant placental abruption are absolute indications to allow labor to progress and often to hasten delivery.
3. CCBs (Nifedipine), prostaglandin inhibitors (Indomethacin), magnesium sulfate, beta-mimetics (ritodrine and terbutaline) and oxytocin antagonist (atosiban).

Question 3

1. What is the main indication for ceserean section?

2. What are the “3 Ps”

Answer 3

1. One of the most common indications for cesarean section is failure to progress (FTP) in labor, most often caused by cephalopelvic disproportion (CPD).
2. The three “Ps” (pelvis, passenger, and power) are primarily responsible for a vaginal delivery. If the pelvis is too small, the fetal presenting part is too large, or the contractions are inadequate, there will be FTP. The strength of uterine contractions can be measured with an intrauterine pressure catheter and augmented with oxytocin, but little can be done about the other two factors that contribute to CPD.

Question 4

1. What are the risk factors associated with Breech presentation?
2. What are the complications of Breech vaginal delivery?
3. What are the types of breech presentation?
4. How do we diagnose it?
5. What is the management?
6. What are the other malpresentations?

Answer 4

1. Factors associated with breech presentation include previous breech delivery, uterine anomalies, polyhydramnios, oligohydramnios, multiple gestation, PPROM, hydrocephaly, and anencephaly. Persistent breech presentation is also associated with placenta previa and fetal anomalies.
2. Complications of a vaginal breech delivery include prolapsed cord and entrapment of the head.
3. Frank, complete and incomplete/footling
4. Abdominal examination (Leopold maneuvers), vaginal examination are used, and ultrasound can be used to confirm the diagnosis.
5. Breech presentation is typically managed with external cephalic version of the breech or elective cesarean delivery.
   6.

Question 5

1. What are the concerning malpositions?
2. What are they associated with?
3. What is the management?

Answer 5

1. Occiput transverse (OT) or occiput posterior (OP).
2. It is seen more commonly with epidural use
3. In either the OT or OP position, if the attempt at rotation or operative vaginal delivery fails, cesarean delivery is commonly required

Question 6

1. What is prolonged deceleration and fetal bradycardia?
2. What are the complications of FHR decelerations?
3. What are the etiologies of prolonged FHR decelerations?
4. How do we diagnose the cause of fetal bradycardia?
5. What is the management of fetal bradycardia?

Answer 6

1. Anytime the FHR is below 100 to 110 beats per minute for longer than 2 minutes, it is called a prolonged deceleration. Longer than 10 minutes is termed bradycardia.
2. These FHR decelerations are associated with a number of complications such as placental abruption, cord prolapse, uterine tetanic contraction, uterine rupture, pulmonary embolus (PE), amniotic fluid embolism (AFE), and seizure. They have also been associated with poor fetal outcome.
3. The etiology of prolonged FHR decelerations can be considered to be preuterine, uteroplacental, or postplacental.
   - Preuterine issues would be any event leading to maternal hypotension or hypoxia. These would include seizure, AFE, PE, Myocardial Infarction (MI), respiratory failure, or recent epidural or spinal placement leading to hypotension.
   - Uteroplacental issues include placental abruption, infarction, and hemorrhaging previa, as well as uterine hyperstimulation.
   - Postplacental etiologies include cord prolapse, cord compression, and rupture of a fetal vessel such as vasa previa.
   4.A simple algorithm to diagnose the etiology of bradycardia is as follows:
   A–> Look at the mother for signs of respiratory compromise or change in mental status. This should commonly diagnose seizures, PE, and AFE.
   B–> While putting on a glove for a cervical examination, assess the maternal BP and heart rate. This will diagnose maternal hypotension, which is commonly seen after epidural placement and is a potential cause of FHR decelerations. This will also aid in determining whether the FHR being recorded could be maternal.
   C–> Immediately before the examination, assess for vaginal bleeding. With increased vaginal bleeding, placental abruption and uterine rupture should be considered. If placentation is unknown, placenta previa is also a possibility. Rarely, vaginal bleeding is secondary to rupture of a fetal vessel, as in vasa previa.
   D–> Examine the patient with one hand on the maternal abdomen and the other hand vaginally feeling for cervical dilation, fetal station, and prolapsed umbilical cord. The abdominal hand should feel for uterine hyperstimulation and fetal parts outside the uterus. If the fetal station is dramatically lower than expected, then the prolonged FHR deceleration may be because of rapid descent and vagal stimulation. If the fetal station is much higher than expected, uterine rupture should be suspected. If the cervix is fully dilated and the fetus is in the pelvis, operative vaginal delivery can be performed if the FHR decelerations do not resolve in a timely fashion.
4. In the setting of prolonged FHR deceleration, the initial management is standardized. The patient is moved to the left or right lateral decubitus position to resolve a FHR deceleration secondary to compression of the inferior vena cava, leading to decreased preload or, more commonly, a compressed umbilical cord by the fetus. Oxygen by face mask is commonly administered to the mother in case hypoxia is an issue. The examination is performed as described above, and the individual etiologies are diagnosed and treated appropriately.
   A–> In the setting of maternal hypotension, the patient can be given aggressive IV hydration and ephedrine.
   B–> Tetanic uterine contraction is treated with nitroglycerin, usually administered via a sublingual spray, and/or terbutaline (a β-agonist tocolytic).
   C–> Umbilical cord prolapse, placenta previa, and placental abruption can all be treated with cesarean section.

Question 7

1. What is shoulder dystocia?
2. What are the risk factors?
3. What are the complications?
4. How do we diagnose shoulder dystocia?
5. What are the maneuvers for delivering an infant with shoulder dystocia?

Answer 7

1. Once the head of the fetus is delivered, if there is difficulty in delivering the shoulders, particularly because of impaction of the anterior shoulder behind the pubic symphysis, this is termed shoulder dystocia.
2. Risk factors for shoulder dystocia include fetal macrosomia (weight greater than 4,000 g), preconceptional and gestational diabetes, previous shoulder dystocia, maternal obesity, postterm pregnancy, prolonged second stage of labor, and operative vaginal delivery.
3. Fetal complications include fractures of the humerus and clavicle, brachial plexus nerve injuries (Erb palsy), phrenic nerve palsy, hypoxic brain injury, and death.
4. The actual diagnosis of a shoulder dystocia is made when routine obstetric maneuvers fail to deliver the fetus. At the time of delivery, suspicion is increased with prolonged crowning of the head and then with the “turtle” sign of either incomplete delivery of the head or the chin tucking up against the maternal perineum.
5. Maneuvers;

• Mcroberts menuver–> Hyperflex of maternal hips
• Suprapubic pressure applied at an oblique
• Rubin maneuver–> Pressure on either accessible shoulder toward the anterior chest
• Wood corkscrew–> Pressure behind the posterior shoulder to rotate the infant
• Delivery of the posterior arm/shoulder
• Perform episiotomy
• Gaskin maneuver–> Fracture or cut fetal clavicle to disimpact the anterior shoulder
• Zavanelli maneuver–> Place infants head back into pelvis and perform ceserean delivery
• Symphysiotomy (this should be reserved for true emergency as it can be complicated by
  following–> Infection, difficulty healing and chronic pain)