Question

A 33-year-old gravida 2, para 1 at 39 weeks of gestation is admitted to the labor suite for a trial of labor. Her obstetric history is significant for a previous low transverse cesarean delivery performed due to breech presentation. She is currently in the active phase of labor, with the cervix dilated to 6 cm and the fetal presenting part at 0 station. Her contractions are strong and occur every 3 minutes. The baseline fetal heart rate is 140/min with moderate variability and no decelerations. Thirty minutes later, the patient suddenly reports an excruciating, tearing pain in her lower abdomen that does not resolve between contractions. Her blood pressure decreases to 88/54 mmHg, and her heart rate increases to 122/min. The electronic fetal monitor reveals a sudden, prolonged deceleration to 70/min that has lasted for over 4 minutes. A repeat pelvic examination demonstrates a cervical dilation of 6 cm, but the fetal presenting part is now palpable at -3 station. Moderate dark red vaginal bleeding is noted. Which of the following is the most appropriate immediate next step in management?