A 17 year old G1P0 Woman at 39 weeks gestation presents to labor and delivery reporting a gush of blood-tinged fluid approximately five hours ago and the onset of uterine contractions shortly thereafter. She reports contractions have become stronger and closer together over the past hour. The fetal heart rate is 140 to 150 with accelerations and no decelerations. Uterine contractions are recorded every 2-3 minutes. A pelvic exam reveals that the cervix is 4 cm dilated and 100 percent effaced. Fetal station is 0. After walking around for 30 minutes the patient is put back in bed after complaining of further discomfort. She requests an epidural. However, obtaining the fetal heart rate externally has become difficult because the patient cannot lie still. What is the most appropriate next step in the management of this patient?