Stephanie R. Goodman

Epinephrine is not a useful addition to intrathecal fentanyl or fentanyl-bupivacaine for labor analgesia

Background and Objectives Intrathecal fentanyl provides effective labor analgesia for a limited time with frequent side effects. We evaluated the effects of adding epinephrine to intrathecal fentanyl with and without bupivacaine. Methods Eighty healthy, term, nulliparous parturients with cervical dilation of 5 cm or less received combined spinal-epidural (CSE) analgesia. Subjects were randomized in a double-blind fashion to 1 of 4 intrathecal solutions containing fentanyl 35 μg with either saline (F); bupivacaine 2.5 mg + saline (FB); bupivacaine 2.5 mg + epinephrine 100 μg (FBE); or epinephrine 100 μg + saline (FE). Patients were evaluated for visual analog pain score, duration of spinal analgesia (time until patient request for additional analgesia), nausea/vomiting, pruritus, sensory and motor block, maternal blood pressure, and fetal heart rate (FHR). Results Intrathecal bupivacaine significantly prolonged fentanyl analgesia with or without epinephrine (P = .018), but epinephrine did not significantly prolong the duration of fentanyl alone or with bupivacaine (F, 92 ± 39 minutes; FB, 125 ± 31 minutes; FBE, 134 ± 42 minutes; and FE, 117 ± 48 minutes). Intrathecal epinephrine was associated with a higher incidence of severe nausea (P = .001), and the FBE group had more lower extremity weakness (P = .047). There was no difference in the incidence of severe pruritus, FHR deceleration, or delivery outcome between the groups. Conclusions These results suggest that intrathecal epinephrine does not prolong the duration of fentanyl or fentanyl with bupivacaine for labor analgesia in nulliparous parturients. Additionally, intrathecal epinephrine did not decrease the incidence of side effects and therefore cannot be recommended.

A randomized trial of breakthrough pain during combined spinal-epidural versus epidural labor analgesia in parous women.

BACKGROUND: There is controversy regarding the benefits and risks of combined spinal-epidural compared with epidural analgesia (CSE, EPID) for labor analgesia. We hypothesized that CSE would result in fewer patient requests for top-up doses compared to EPID. METHODS: One-hundred ASA physical status I or II parous women at term in early labor (<5 cm cervical dilation) requesting analgesia were randomized in double-blind fashion to the EPID group (epidural bupivacaine 2.5 mg/mL, 3 mL, followed by bupivacaine 1.25 mg/mL, 10 mL with fentanyl 50 &mgr;g) or the CSE group (intrathecal bupivacaine 2.5 mg with fentanyl 25 &mgr;g). Both groups received identical infusions of bupivacaine 0.625 mg/mL with fentanyl 2 &mgr;g/mL at 12 mL/h. The primary outcome variable was the number of top-up doses requested to treat breakthrough pain. RESULTS: There was no significant difference between the two groups in the percentage of patients requesting top-up doses (44% CSE vs 51% EPID; 95% confidence interval of the difference −28% to +14%) nor in the need for multiple top-up doses (14% CSE vs 15% EPID). Visual analog scale scores were lower in the CSE group compared to the EPID group at 10 min after initiation of analgesia [median 0 cm (0, 0) vs 4 cm (1, 6) respectively, P < 0.001] and at 30 min [0 cm (0, 0) vs 0 cm (0, 1), respectively, P = 0.03]. CONCLUSIONS: We did not find a difference in the need for top-up doses in parous patients; however, CSE provided better analgesia in the first 30 min compared to EPID.

Decreased postpartum use of oral pain medication after a single dose of epidural morphine

Background: Pain after vaginal delivery may result from episiotomy, perineal laceration, or uterine involution. Many women have indwelling epidural catheters in place at delivery. We hypothesized that a small dose of epidural morphine would be an effective strategy for postpartum analgesia. Methods: Eighty-one healthy parturients receiving epidural analgesia for labor were enrolled. Patients were randomized in double-blind fashion to 1 of 3 groups: all groups received a 4-mL volume of epidural solution consisting of saline (group 1, control), 1 mg (group 2), or 2 mg morphine (group 3) after vaginal delivery. During the first 24 hours postpartum, patients were evaluated for the amount of oral pain medication requested; visual analog scale scores for pain at rest and with movement; satisfaction with postpartum pain treatment; and opioid side effects including nausea, pruritus, urinary retention, and respiratory depression. Results: Patients who received 2 mg of epidural morphine used an average of 0.7 (0--1, interquartile range) opioid-containing pain pills (acetaminophen with codeine or oxycodone) compared with 1.2 (0-2) in the 1-mg group and 1.9 (0-3) in the control group (P = .07). There was a statistically significant difference in oral drug usage between those who received epidural morphine and those who did not (P < .03). There were no differences in side effects except that at 12 hours postpartum there was an increase in Foley catheterization in the 1-mg morphine group (P = .007). Conclusions: These results suggest that epidural morphine decreases the need for oral pain medication in the first 24 hours postpartum. No significant dose-dependent side effects were found.

Left Lateral Table Tilt for Elective Cesarean Delivery under Spinal Anesthesia Has No Effect on Neonatal Acid-Base Status: A Randomized Controlled Trial.

BACKGROUND Current recommendations for women undergoing cesarean delivery include 15° left tilt for uterine displacement to prevent aortocaval compression, although this degree of tilt is practically never achieved. We hypothesized that under contemporary clinical practice, including a crystalloid coload and phenylephrine infusion targeted at maintaining baseline systolic blood pressure, there would be no effect of maternal position on neonatal acid base status in women undergoing elective cesarean delivery with spinal anesthesia. METHODS Healthy women undergoing elective cesarean delivery were randomized (nonblinded) to supine horizontal (supine, n = 50) or 15° left tilt of the surgical table (tilt, n = 50) after spinal anesthesia (hyperbaric bupivacaine 12 mg, fentanyl 15 μg, preservative-free morphine 150 μg). Lactated Ringers 10 ml/kg and a phenylephrine infusion titrated to 100% baseline systolic blood pressure were initiated with intrathecal injection. The primary outcome was umbilical artery base excess. RESULTS There were no differences in umbilical artery base excess or pH between groups. The mean umbilical artery base excess (± SD) was -0.5 mM (± 1.6) in the supine group (n = 50) versus -0.6 mM (± 1.5) in the tilt group (n = 47) (P = 0.64). During 15 min after spinal anesthesia, mean phenylephrine requirement was greater (P = 0.002), and mean cardiac output was lower (P = 0.014) in the supine group. CONCLUSIONS Maternal supine position during elective cesarean delivery with spinal anesthesia in healthy term women does not impair neonatal acid-base status compared to 15° left tilt, when maternal systolic blood pressure is maintained with a coload and phenylephrine infusion. These findings may not be generalized to emergency situations or nonreassuring fetal status.

Obstetric anesthesia: not just for cesareans and labor.

The scope of obstetric anesthesia practice ranges far beyond the delivery of care to women for vaginal and cesarean deliveries. Increasingly, obstetric anesthesiologists are involved in the management of anesthetics for new procedures and for new indications. Anesthesia is frequently needed for maternal procedures, as well as fetal procedures, and at varying times in the intrapartum period. Maternal-specific procedures include cerclage, external cephalic version (ECV), postpartum bilateral tubal ligation (BTL), and dilation and evacuation (D and E). Fetus-specific procedures include fetoscopic laser photocoagulation and ex-utero intrapartum treatment (EXIT). This review will not include discussion of the anesthetic management of non-obstetric surgery during pregnancy, such as appendectomy or cholecystectomy.

Complications with 25-gauge and 27-gauge Whitacre needles during combined spinal-epidural analgesia in labor

Needle size and shape may influence the incidence of paresthesias, post-dural puncture headache and other complications during combined spinal-epidural (CSE) procedures. We have noted a relatively high incidence of transient paresthesias during placement of the spinal needle during CSE for labor analgesia. The purpose of this study was to compare the occurrence of paresthesia and post-dural puncture headache in parturients who received CSE analgesia with either a 25-gauge or 27-gauge Whitacre needle. In a prospective observational study, data were gathered from 478 consecutive women receiving labor analgesia. Incidence, duration, and character of any paresthesias upon spinal needle placement and the incidence and treatment of headache were recorded. The incidence of paresthesia with the two needles was similar (16% with 25-gauge vs 15.4% with 27 gauge) but the incidence of post-dural puncture headache was higher with the 25-gauge needle (4% vs 0.7% with 27 gauge, P < 0.05). Our data suggest that with Whitacre needles, 27-gauge might be preferable to 25-gauge needles to reduce the rate of post-dural puncture headache in parturients but that they do not alter the incidence of transient paresthesias.

EPINEPHRINE IS NOT A USEFUL ADDITION TO INTRATHECAL FENTANYL OR FENTANYL-BUPIVACAINE FOR LABOR ANALGESIA

Background and Objectives: Intrathecal fentanyl provides effective labor analgesia for a limited time with frequent side effects. We evaluated the effects of adding epinephrine to intrathecal fentanyl with and without bupivacaine. Methods: Eighty healthy, term, nulliparous parturients with cervical dilation of 5 cm or less received combined spinal‐epidural (CSE) analgesia. Subjects were randomized in a double‐blind fashion to 1 of 4 intrathecal solutions containing fentanyl 35 &mgr;g with either saline (F); bupivacaine 2.5 mg + saline (FB); bupivacaine 2.5 mg + epinephrine 100 &mgr;g (FBE); or epinephrine 100 &mgr;g + saline (FE). Patients were evaluated for visual analog pain score, duration of spinal analgesia (time until patient request for additional analgesia), nausea/vomiting, pruritus, sensory and motor block, maternal blood pressure, and fetal heart rate (FHR). Results: Intrathecal bupivacaine significantly prolonged fentanyl analgesia with or without epinephrine (P = .018), but epinephrine did not significantly prolong the duration of fentanyl alone or with bupivacaine (F, 92 ± 39 minutes; FB, 125 ± 31 minutes; FBE, 134 ± 42 minutes; and FE, 117 ± 48 minutes). Intrathecal epinephrine was associated with a higher incidence of severe nausea (P = .001), and the FBE group had more lower extremity weakness (P = .047). There was no difference in the incidence of severe pruritus, FHR deceleration, or delivery outcome between the groups. Conclusions: These results suggest that intrathecal epinephrine does not prolong the duration of fentanyl or fentanyl with bupivacaine for labor analgesia in nulliparous parturients. Additionally, intrathecal epinephrine did not decrease the incidence of side effects and therefore cannot be recommended. Reg Anesth Pain Med 2002;27:374‐379.