A 33-year-old woman, gravida 3 para 2, at 37 weeks gestation is admitted in active labor. The patient's first child was born via cesarean delivery for breech presentation, and her second was born via spontaneous vaginal delivery. She receives epidural analgesia on admission and her contractions become nonpainful. An intrauterine pressure catheter is placed due to variable decelerations, which resolve with amnioinfusion. The patient reaches a cervical dilation of 10 cm and 100% effacement; the fetal vertex is at +1 station. After she pushes for 20 minutes, there is a sudden onset of abdominal pain, which is initially intermittent but becomes constant after a few minutes. The fetal heart rate tracing is shown in the following exhibit. On repeat examination, the cervix is 10 cm dilated and 100% effaced, and the fetal vertex has retracted to ?2 station. Which of the following is the best next step in management of this patient?

Question

A 33-year-old woman, gravida 3 para 2, at 37 weeks gestation is admitted in active labor.  The patient's first child was born via cesarean delivery for breech presentation, and her second was born via spontaneous vaginal delivery.  She receives epidural analgesia on admission and her contractions become nonpainful.  An intrauterine pressure catheter is placed due to variable decelerations, which resolve with amnioinfusion.  The patient reaches a cervical dilation of 10 cm and 100% effacement; the fetal vertex is at +1 station.  After she pushes for 20 minutes, there is a sudden onset of abdominal pain, which is initially intermittent but becomes constant after a few minutes.  The fetal heart rate tracing is shown in the following exhibit.  On repeat examination, the cervix is 10 cm dilated and 100% effaced, and the fetal vertex has retracted to ?2 station.  Which of the following is the best next step in management of this patient?

Quizplus · Accepted Answer

Explanation: 11ec25c8_da19_717e_bc81_6f590c218dc8_MD0003_00 This laboring patient with sudden-onset abdominal pain likely has uterine rupture, a full-thickness myometrial tear. Uterine rupture typically occurs in patients with prior uterine surgery (eg, prior cesarean delivery regardless of subsequent vaginal delivery) because inelastic uterine scar tissue can separate with contractions. When the uterus ruptures, maternal and fetal compromise occurs by multiple mechanisms: If the placenta is involved, fetal perfusion is disrupted, leading to fetal hypoxia (ie, late decelerations, prolonged bradycardia). If the umbilical cord prolapses into the maternal abdomen, cord compression may increase (ie, variable decelerations). Because either or both are likely to occur, an abrupt fetal heart rate tracing abnormality is the most common finding of uterine rupture. Disordered contractions occur because ruptured myometrial fibers cannot contract in unison. This is often evidenced by progressively decreasing contraction amplitude (ie, staircase sign on tocodynamometry). Partial fetal delivery into the maternal abdomen can cause fetal head retraction (eg, +1 to ?2 station) and loss of fetal station. Myometrial tearing causes severe abdominal pain and massive intraabdominal bleeding, which may result in hemodynamic instability. Uterine rupture is an obstetric emergency and requires emergency laparotomy and cesarean delivery for immediate delivery and uterine repair. (Choice A) Although amnioinfusion alleviates umbilical cord compression, it does not resolve prolonged fetal bradycardia caused by placental disruption. (Choice C) The McRoberts maneuver with suprapubic pressure facilitates delivery in patients with shoulder dystocia. This condition can present with fetal head retraction against the perineum (ie, turtle sign); however, it does not cause sudden, severe abdominal pain. shoulder dystocia (Choice D) Vacuum-assisted vaginal delivery may be performed in patients who are 10 cm dilated and require immediate delivery (eg, nonreassuring fetal heart rate). In this patient, however, fetal head retraction to ?2 station has made this procedure unsafe. In addition, vaginal delivery does not address this patient's uterine rupture, which requires laparotomy to repair. (Choice E) Oxytocin infusion increases contraction frequency and strength in patients with inadequate contractions. However, it is not administered in the setting of acute fetal bradycardia due to the risk of further fetal compromise. Educational objective: Patients with prior uterine surgery (eg, cesarean delivery) are at increased risk for uterine rupture, which can present with abdominal pain, fetal heart rate tracing abnormalities, progressively decreasing contraction amplitude, and loss of fetal station. Management is with emergency laparotomy and cesarean delivery. References: Risk factors for uterine rupture and neonatal consequences of uterine rupture: a population-based study of successive pregnancies in Sweden. (http://www.ncbi.nlm.nih.gov/pubmed/17877673) ACOG practice bulletin no. 205: vaginal birth after cesarean delivery. (http://www.ncbi.nlm.nih.gov/pubmed/30681543)

A 33-Year-Old Woman, Gravida 3 Para 2, at 37 Weeks