A 19-year-old P0 at 41 weeks presents in spontaneous labor. Her membranes rupture spontaneously after she is admitted to labor and delivery, demonstrating meconium-stained amniotic fluid.
What is the best management strategy for this patient and fetus at the time of delivery?
In 2006, the American Academy of Pediatrics and the American Heart Association published new guidelines on neonatal resuscitation, which the American College of Obstetricians and Gynecologists adopted as well. Infants with meconium-stained amniotic fluid should no longer receive routine intrapartum suctioning, which used to be the standard of care. Current evidence no longer supports this practice, because routine intrapartum suctioning has not been shown to prevent or alter the course of meconium aspiration syndrome. If the newborn is depressed, tracheal suctioning should be undertaken. Attempted intubation of a vigorous newborn may potentially result in more injuries to the vocal cords.
A 38-year-old G3P2 at 40 weeks’ gestation presents to labor and delivery with gross rupture of membranes occurring 1 hour prior to arrival. The patient is having contraction every 3 to 4 minutes on the external tocometer, and each contraction lasts 60 seconds. The FHR tracing is 120 beats per minute with accelerations and no decelerations. The patient has a history of rapid vaginal deliveries, and her largest baby was 3200 g. On cervical examination she is 5-cm dilated and completely effaced, with the vertex at -2 station. The estimated fetal weight is 3300 g. The patient is in a lot of pain and requesting medication.
Which of the following is the most appropriate method of pain control for this patient?
The most appropriate modality for pain control in this patient is administration of an epidural analgesia. An epidural block provides relief from the pain of uterine contractions and delivery. It is accomplished by injecting a local anesthetic agent into the epidural space at the level of the lumbar intervertebral space. An indwelling catheter can be left in place to provide continuous infusion of an anesthetic agent throughout labor and delivery via a volumetric pump. In this patient, intramuscular narcotics such as meperidine or morphine would not be preferred because these agents can cause respiratory depression in the newborn if delivery is imminent. A pudendal block involves local infiltration of the pudendal nerve, which provides anesthesia to the perineum for delivery but no pain relief for uterine contractions. A local perineal block refers to infusing a local anesthetic to the area of an episiotomy. The inhalation of anesthetic gases (general anesthesia) is reserved primarily for situations involving emergent cesarean deliveries and difficult deliveries. All anesthetic agents that depress the maternal CNS cross the placenta and affect the fetus. In addition, a major complication of general anesthesia is maternal aspiration, which can result in aspiration pneumonitis.
A 35-year-old G2P1 at 39 weeks’ gestation presents to labor and delivery in active labor. Her cervix is 5-cm dilated and 80% effaced, and the vertex is at 0 station. The tocometer shows that she is having contractions every 3 minutes. The fetal heart tracing shows a baseline rate of 140 beats per minute, moderate variability, with accelerations and no decelerations.
This FHR tracing may best be interpreted as which of the following?
In 2008, a workshop sponsored by the American College of Obstetricians and Gynecologists, the National Institute of Child Health and Human Development, and the Society for Maternal-Fetal Medicine convened to update fetal heart tracing nomenclature and interpretation. A normal baseline FHR is 110 beats per minute to 160 beats per minute. Moderate (normal) variability is an amplitude range of 6 beats per minute to 25 beats per minute. An acceleration is an abrupt increase in the FHR, with onset to peak in less than 30 seconds. If an acceleration lasts 10 minutes or longer, it is a baseline change. The committee adopted a threetiered FHR interpretation system. Category I tracings include: baseline FHR 110 beats per minute to 160 beats per minute, moderate variability, no decelerations, and either presence or absence of accelerations. A category II tracing includes all tracings not categorized as category I or III. These tracings require evaluation, increased surveillance, initiation of corrective measures where appropriate, and reevaluation. They may include tachycardia, minimal variability, absence of induced accelerations after fetal stimulation, or episodic decelerations. Category III tracings include either absent variability with recurrent late decelerations, recurrent variable decelerations, or bradycardia, or a sinusoidal pattern. Category III tracings are abnormal and indicate an increased risk for fetal academia. If unresolved, these tracings usually require prompt delivery.
One hour after she is admitted, her membranes rupture spontaneously. Shortly thereafter, she develops recurrent variable decelerations.
What is the best next step in management?
Intermittent variable decelerations by definition occur with fewer than 50% of contractions. They are the most common FHR abnormality that occurs during labor, and typically do not require treatment. Recurrent variable decelerations by definition occur with greater than or equal to 50% of contractions and may be more indicative of impending fetal academia. Management of recurrent variables should include relieving umbilical cord compression. Changing the maternal position is a reasonable first step. Amnioinfusion has been shown to decrease both recurrent variables and the cesarean delivery rate. Terbutaline and oxygen are not indicated for treatment of recurrent variable decelerations.
A 29-year-old G2P1 at 40 weeks is in active labor. Her cervix is 5-cm dilated, completely effaced, and the vertex is at 0 station. She is on oxytocin to augment her labor, and she has just received an epidural for pain management. The nurse calls you to the room because the FHR has been in the 70s for the past 3 minutes. The contraction pattern is noted to be every 3 minutes, each lasting 60 seconds, with return to normal tone in between contractions. The patient’s vital signs are: blood pressure 90/40 mm Hg, pulse 105 beats per minute, respiratory rate 18 breaths per minute, and temperature 36.1°C (97.6°F). On repeat cervical examination, the vertex is well applied to the cervix and the patient remains 5-cm dilated and at 0 station, and no vaginal bleeding is noted.
Which of the following is the most likely cause for the deceleration?
A prolonged FHR deceleration is a decrease in the FHR that is 15 beats per minute or more, lasting 2 minutes or longer, but less than 10 minutes from onset to return to baseline. Epidural analgesia is a common cause of FHR decelerations because it can be associated with maternal hypotension and decreased placental perfusion. Therefore, maternal blood pressure should always be noted in cases of FHR decelerations. If maternal blood pressure is abnormally low, ephedrine can be given to correct the hypotension. Because an umbilical cord prolapse can be associated with decelerations, the patient should undergo a cervical examination to evaluate for a prolapsed cord. In addition, the Pitocin infusion should be discontinued to reduce uterine contraction frequency. The patient should be turned to the left lateral position to decrease uterine pressure on the great vessels and enhance uteroplacental flow. Supplemental oxygen should be given to the patient in an attempt to increase oxygen to the fetus. A cesarean delivery may be performed if the FHR does not respond to these resuscitative measures.