150 The effect of maternal position on fetal heart rate during epidural or intrathecal labor analgesia Robert L. Eberle, MD, a Mark C. Norris, MD, c Angela Mallozzi Eberle, MD, b J. Steven Naulty, MD, d and Valerie A. Arkoosh, MD e Albany, New York, St. Louis, Missouri, and Philadelphia, Pennsylvania OBJECTIVE: This study was designed to determine the relationship between maternal position and the inci- dence of prolonged decelerations after epidural bupivacaine or intrathecal sufentanil analgesia for labor. STUDY DESIGN: Laboring, healthy, term parturient women, with reassuring fetal heart rate tracings, re- questing either epidural (n = 145) or intrathecal (n = 160) analgesia were randomly assigned to lie either supine with measured 30-degree left uterine displacement (n = 136) or in the left lateral decubitus position (n = 145). Patients received either intrathecal sufentanil, 10 μg, or epidural 0.25% bupivacaine, 13 mL. An ob- stetrician, unaware of patient position or type of anesthesia, examined the fetal heart rate tracings. RESULTS: No demographic differences were noted among the groups. Prolonged decelerations occurred with equal frequency after epidural bupivacaine and intrathecal sufentanil (3.9%). Prolonged decelerations were not related to maternal position. No emergency cesarean deliveries were performed as a result of pro- longed decelerations. Prolonged decelerations correlated with the frequency of contractions before induction of analgesia (P < .05). Fewer fetal heart rate accelerations were noted after intrathecal sufentanil than after epidural bupivacaine (P < .005). More ephedrine was used after epidural bupivacaine (P < .001). Patients who received epidural analgesia in the left lateral position were more likely to have an asymmetric block ( P < .05). CONCLUSIONS: The risk of prolonged deceleration after epidural bupivacaine or intrathecal sufentanil labor analgesia is unrelated to maternal position or analgesic technique. (Am J Obstet Gynecol 1998;179:150-5.) The cause of prolonged decelerations after neuraxial labor analgesia remains controversial. After epidural bupivacaine analgesia, Preston et al 1 attributed severe fetal heart rate (FHR) changes to occult aortocaval com- pression. They reported that 15% (6/38) of women nursed in the wedged supine position had severe FHR decelerations compared with 0 of the 40 women nursed in the full lateral position. 1 We designed this study to con- firm the effect of maternal position on the incidence of prolonged fetal decelerations and other periodic FHR changes after epidural analgesia and to extend these data to women receiving intrathecal sufentanil analgesia. Material and methods After securing Thomas Jefferson University and Pennsylvania Hospital approval, we obtained verbal con- sent from 305 healthy term (37 weeks’ gestation or greater) laboring parturient women with singleton, ver- tex pregnancies from September 1994 through June 1995. A total of 152 patients were enrolled at Thomas Jefferson University and 153 at Pennsylvania Hospital. Patients with both spontaneous and oxytocin-augmented labor were included. We excluded patients with nonreas- suring FHR tracings, multiple gestations, fetal anomalies, known substance abuse, intrauterine growth restriction, oligohydramnios, polyhydramnios, hypertension, and preeclampsia. The patients chose the type of labor anal- gesia they wished to receive on the basis of obstetrician, anesthesiologist, or patient preference. They were ran- domly assigned to lie either supine with 30-degree left uterine displacement or in the left lateral decubitus posi- tion for 45 minutes after induction of analgesia. All patients received 500 to 1000 mL of intravenous crystalloid before induction of analgesia as per standard practice at the two institutions. With the patients in the sitting position we inserted an 18-gauge Hustead needle at the L2-3 or L3-4 interspace and identified the epidural space using loss of resistance to air or saline solution. For patients choosing intrathecal sufentanil, a 24- gauge 120 mm Sprotte needle was inserted through the Hustead needle. After obtaining free-flowing cere- brospinal fluid, we injected sufentanil, 10 μg, in 3 mL of preservative-free saline solution (time 0). A polyamide catheter was inserted 3 to 5 cm into the epidural space. From the Departments of Anesthesiology a and Obstetrics and Gynecology and Maternal-Fetal Medicine, b Albany Medical College, the Department of Anesthesiology, Washington University, c the Department of Anesthesiology, Pennsylvania Hospital, d and the Department of Anesthesiology, Allegheny University of the Health Sciences. e Supported in part by Optimark Corporation, Warwick, New York. Received for publication July 29, 1997; revised September 15, 1997; ac- cepted December 9, 1997. Reprint requests: Robert L Eberle, MD, Albany Medical College, Department of Anesthesiology, A-131, 47 New Scotland, Albany, NY 12208-3479. Copyright © 1998 by Mosby, Inc. 0002-9378/98 $5.00 + 0 6/1/88064