A randomized trial of labor analgesia in women with pregnancy-induced hypertension.

OBJECTIVE: The purpose of this study was to compare the peripartum and perinatal effects of epidural with intravenous labor analgesia in women with pregnancy-induced hypertension. STUDY DESIGN: Women with pregnancy-induced hypertension who had consented to participate were randomized to receive either epidural or intravenous analgesia for labor pain. Both methods were given according to standardized protocols. All women received magnesium sulfate seizure prophylaxis. Obstetric and neonatal outcomes were compared according to intent-to-treat allocation. RESULTS: Seven hundred thirty-eight women were randomized: 372 women were given epidural analgesia, and 366 women were given intravenous analgesia. Maternal characteristics were similar, including the severity of hypertension. Epidural analgesia was associated with a significantly prolonged second-stage labor, an increase in forceps deliveries, and an increase in chorioamnionitis. Cesarean delivery rates and neonatal outcomes were similar. Pain relief was superior with the epidural method. Hypotension required treatment in 11% of women in the epidural group. CONCLUSION: Epidural labor analgesia provides superior pain relief but no additional therapeutic benefit to women with pregnancy-induced hypertension.

A randomized study of combined spinal-epidural analgesia versus intravenous meperidine during labor: impact on cesarean delivery rate.

BACKGROUND: Combined spinal-epidural (CSE) analgesia produces rapid-onset pain relief and allows ambulation in early labor. Epidural local anesthetics may contribute to an increase in operative deliveries by decreasing perineal sensation and causing motor weakness. Operative delivery rates might be reduced with CSE, by avoiding or delaying administration of local anesthetics. This study compares the operative delivery rates associated with a CSE technique and those associated with intravenous meperidine for labor analgesia. METHODS: Healthy parturients at full term were assigned randomly to receive CSE or intravenous meperidine analgesia. The CSE group received 10 microg intrathecal sufentanil, followed by epidural bupivacaine and fentanyl at their next request for analgesia. Parturients receiving intravenous meperidine had 50 mg on demand (maximum, 200 mg in 4 h). Labor and delivery outcomes in both groups were recorded and compared. RESULTS: An intent-to-treat analysis of 1,223 women indicated that CSE does not increase the rate of cesarean delivery for dystocia in nulliparous and parous women (CSE, 3.5% vs. intravenous meperidine, 4; P=not significant) or in nulliparous women alone (CSE, 7% vs. intravenous meperidine, 8%; P=not significant). Profound fetal bradycardia that necessitated emergency cesarean delivery within 1 h of the time the mother received sufentanil occurred in 8 of 400 parturients (compared with 0 of 352 who received meperidine; P < 0.01). However, the method of fetal monitoring differed between the two groups. Despite this, neonatal outcomes were similar overall. CONCLUSIONS: Combined spinal-epidural analgesia during labor does not increase the cesarean delivery rate for dystocia in healthy parturient patients at full term, regardless of parity. However, an unexpected increase in the number of cesarean deliveries for profound fetal bradycardia after intrathecal sufentanil was observed. Further investigation is warranted.

Cesarean delivery: a randomized trial of epidural versus patient-controlled meperidine analgesia during labor.

BACKGROUND: Reports indicate that the administration of epidural analgesia for pain relief during labor interferes with labor and increases cesarean deliveries. However, only a few controlled trials have assessed the effect of epidural analgesia on the incidence of cesarean delivery. The authors' primary purpose in this randomized study was to evaluate the effects of epidural analgesia on the rate of cesarean deliveries by providing a suitable alternative: patient-controlled intravenous analgesia. METHODS: Seven hundred fifteen women of mixed parity in spontaneous labor at full term were randomly assigned to receive either epidural analgesia or patient-controlled intravenous meperidine analgesia. Epidural analgesia was maintained with a continuous epidural infusion of 0.125% bupivacaine with 2 microg/ml fentanyl. Patient-controlled analgesia was maintained with 10-15 mg meperidine given every 10 min as needed using a patient-controlled pump. Procedures recorded in a manual that prescribed the intrapartum management were followed for each woman randomized in the study. RESULTS: A total of 358 women were randomized to receive epidural analgesia, and 243 (68%) of these women complied with the epidural analgesia protocol. Similarly, 357 women were randomized to receive patient-controlled intravenous meperidine analgesia, and 259 (73%) of these women complied with the patient-controlled intravenous analgesia protocol. Only five women who were randomized and received patient-controlled intravenous meperidine analgesia according to the protocol crossed over to epidural analgesia due to inadequate pain relief. There was no difference in the rate of cesarean deliveries between the two analgesia groups using intention-to-treat analysis based on the original randomization (epidural analgesia, 4% [95% CI: 1.9-6.2%] compared with patient-controlled intravenous analgesia, 5% [95% CI: 2.6-7.2%]). Similar results were observed for the analysis of the protocol-compliant groups (epidural analgesia, 5% [95% CI: 2.6-8.5%] compared with patient-controlled intravenous analgesia, 6% [95% CI: 3-8.9%]). Women who received epidural analgesia reported lower pain scores during labor and delivery compared with women who received patient-controlled intravenous analgesia. CONCLUSIONS: Epidural analgesia was not associated with increased numbers of cesarean delivery when compared with a suitable alternative method of analgesia.

Prevention of hypotension during spinal anesthesia: a comparison of intravascular administration of hetastarch versus lactated Ringer's solution.

This study was designed to compare the efficacy of 6% hetastarch to that of crystalloid administration in reducing the incidence and severity of hypotension during spinal anesthesia. Forty ASA grade I patients scheduled for postpartum tubal ligations under spinal anesthesia were randomly allocated to receive either 500 mL of hetastarch solution or 1000 mL of lactated Ringer's solution prior to spinal anesthesia. Spinal anesthesia was managed identically in both groups by anesthesiologists who were unaware of the type of fluid administered. The incidence of hypotension was 11 of 21 (52%) in the lactated Ringer's solution group and 3 of 19 (16%) in the hetastarch group. The difference in the incidence of hypotension was significant (P < 0.05). The requirement of 5-mg bolus doses of ephedrine to maintain systolic arterial blood pressure > 75% of baseline was significantly greater in the lactated Ringer's group than in the hetastarch group (15 vs 4, P < 0.05). We conclude that an intravenous infusion of 500 mL of 6% hetastarch solution is more effective than 1000 mL lactated Ringer's solution in attenuating spinal anesthesia induced hypotension in women undergoing postpartum tubal ligation.

EMLA cream effectively reduces the pain of spinal needle insertion.

BACKGROUND AND OBJECTIVE: EMLA cream is an effective topical anesthetic, which is commonly used for analgesia during venous cannulation in the pediatric population. This study was designed to compare the efficacy of EMLA cream with that of infiltration with lidocaine in relieving the pain associated with administration of spinal anesthesia. METHODS: The patient population consisted of 41 ASA status I and II women scheduled for postpartum tubal ligation. Spinal anesthesia was administered with a 25-gauge spinal needle via a 20-gauge introducer. The patients were randomly allocated to receive either EMLA cream for a minimum of 30 minutes or infiltration with 3 mL of 1% lidocaine prior to spinal needle insertion. Pain during spinal needle insertion was assessed immediately after each procedure by a 10-cm visual analog scale. RESULTS: Pain scores were significantly lower in the EMLA group (mean, 1.5) than in the lidocaine group (mean, 3.52) (P < .001). The number of patients satisfied with the method of analgesia was significantly higher in the EMLA than in the lidocaine group (90% vs 55%, P < .05). CONCLUSION: EMLA cream is an effective alternative to lidocaine infiltration for analgesia during the administration of spinal anesthesia when using a 25-gauge spinal needle via a 20-gauge introducer. Application of EMLA cream for at least 30 minutes prior to spinal needle insertion is adequate to provide good analgesia during needle insertion.

Randomized trial of epidural versus intravenous analgesia during labor.

OBJECTIVE: To compare the effects of epidural analgesia with intravenous (IV) analgesia on the outcome of labor. METHODS: Thirteen hundred thirty women with uncomplicated term pregnancies and in spontaneous labor were randomized to be offered epidural bupivacaine-fentanyl or IV meperidine analgesia during labor. RESULTS: Comparison of the allocation groups by intent to treat revealed a significant association between epidural allocation and operative delivery for dystocia. However, only 65% of each randomization group accepted the allocated treatment. Four hundred thirty-seven women accepted and received meperidine as allocated, and they were compared with 432 women accepting epidural allocation. Significant associations resulted between epidural administration and prolongation of labor, increased rate of oxytocin administration, chorioamnionitis, low forceps, and cesarean delivery. Because of the high rate of noncompliance with treatment allocation, a multifactorial regression analysis was performed on the entire cohort, and a twofold relative risk of cesarean delivery persisted in association with epidural treatment. The impact of epidural treatment on cesarean delivery was significant for both nulliparous and parous women (risk ratios 2.55 and 3.81, respectively). Epidural analgesia provided significantly better pain relief in labor than did parenteral meperidine. CONCLUSION: Although labor epidural analgesia is superior to meperidine for pain relief, labor is prolonged, uterine infection is increased, and the number of operative deliveries are increased. A two- to fourfold increased risk of cesarean delivery is associated with epidural treatment in both nulliparous and parous women.

The pregnant patient with an intracranial arteriovenous malformation. Cesarean or vaginal delivery using regional or general anesthesia?

BACKGROUND AND OBJECTIVES: A parturient with large intracranial arteriovenous malformation presented for elective cesarean delivery. METHODS: The anesthetic technique included acute hydration with intravenous crystalloid followed by continuous epidural anesthesia with bupivacaine and fentanyl and oxygen by face mask. Intraoperative monitoring consisted of electrocardiography, pulse oximetry, invasive arterial blood pressure, and analysis of arterial blood gases. Postoperative analgesia in the immediate postoperative period was provided by a continuous epidural infusion of bupivacaine and fentanyl followed by intravenous patient-controlled analgesia using a mixture of morphine and droperidol. RESULTS: A cesarean delivery was successfully performed and both mother and infant were eventually discharged from the hospital in good condition. CONCLUSIONS: In this case report the choice of obstetric management (cesarean versus vaginal delivery) of a full-term parturient with an intracranial arteriovenous malformation is discussed, and the rationale for the preference of epidural anesthesia for the cesarean delivery is presented.

Randomized comparison of general and regional anesthesia for cesarean delivery in pregnancies complicated by severe preeclampsia.

OBJECTIVE: To evaluate the maternal and fetal effects of three anesthetic methods used randomly in women with severe preeclampsia who required cesarean delivery. METHODS: Eighty women with severe preeclampsia, who were to be delivered by cesarean, were randomized to general (26 women), epidural (27), or combined spinal-epidural (27) anesthesia. The mean preoperative blood pressure (BP) was approximately 170/110 mmHg, and all women had proteinuria. Anesthetic and obstetric management included antihypertensive drug therapy and limited intravenous (IV) fluid and drug therapy. RESULTS: The mean gestational age at delivery was 34.8 weeks. All infants were born in good condition as assessed by Apgar scores and umbilical arterial blood gas determinations. Maternal hypotension resulting from regional anesthesia was managed without excessive IV fluid administration. Similarly, maternal BP was managed without severe hypertensive effects in women undergoing general anesthesia. There were no serious maternal or fetal complications attributable to any of the three anesthetic methods. CONCLUSION: General as well as regional anesthetic methods are equally acceptable for cesarean delivery in pregnancies complicated by severe preeclampsia if steps are taken to ensure a careful approach to either method.

Comparison of 26-gauge Atraucan and 25-gauge Whitacre needles: insertion characteristics and complications.

Ninety-six women undergoing post-partum tubal ligation under spinal anaesthesia were studied to compare 26G Atraucan with 25G Whitacre spinal needles for ease of insertion, number of attempts at needle insertion, cerebrospinal fluid (CSF) flow characteristics through the needles, quality of subsequent analgesia, and incidence of perioperative complications. A higher rate of successful dural puncture at the first attempt (40/50 vs 27/46, P < 0.05) and faster (mean +/- SD, 11.5 +/- 2.2 vs 13.5 +/- 2.4, P < 0.001) CSF flow through the needle was achieved with the Atraucan than with the Whitacre needle. The incidence of failed spinal (4% vs 5%) and post-dural puncture headache (PDPH) (4% vs 4.3%) was similar with both needles, but more patients experienced paraesthesiae during needle insertion with the Whitacre than with the Atraucan needle (15% vs 2%, P < 0.05). We conclude that the use of the 26G Atraucan needle is associated with a higher rate of successful identification of the subarachnoid space at the first attempt, faster CSF backflow, and fewer paraesthesia when compared with the 25G Whitacre needle.

A survey of obstetric patients who refuse regional anaesthesia.

One hundred obstetric patients presenting for elective surgery who had refused regional anaesthesia were interviewed just prior to entering the operating room. In each case, the reason for refusing a regional technique was recorded. The most frequent reasons given were fear of backache (33%) and fear of the needle (28%). Anaesthetists should be aware of patients' concerns and be able to discuss the relevant issues.

Fetal acidemia associated with regional anesthesia for elective cesarean delivery.

OBJECTIVE: To determine the prevalence, magnitude, and type of fetal acidemia associated with contemporary obstetric anesthetic techniques. METHODS: Umbilical artery blood gases were obtained in 1601 singleton pregnancies delivered by elective cesarean. RESULTS: General anesthesia was used in 371 (23%) women, epidural in 286 (18%), combined spinal-epidural in 659 (41%), and spinal in 231 (14%). Approximately 18% of infants exposed to regional anesthetics had umbilical artery blood pH values 7.19 or less, 42 (3%) infants had pH values less than 7.10, and nine (1%) had values 6.99 or less. The incidence of fetal acidemia was greater in spinal and combined spinal-epidural procedures compared to epidural anesthetics. Fetal acidemia was predominantly respiratory in type because carbon dioxide pressure was abnormally increased when fetal acidemia was diagnosed. CONCLUSIONS: Regional anesthesia is associated with fetal acidemia, occasionally severe, and has features of an acute respiratory type of acidemia. Fetal acidemia is less frequent with epidural anesthesia compared to subarachnoid techniques.

Penicillin levels following the administration of benzathine penicillin G in pregnancy.

OBJECTIVE: To investigate the distribution of penicillin in the maternal-placental-fetal unit at term gestation. METHODS: Twenty-five healthy gravidas at 38-39 weeks' gestation scheduled for elective repeat cesarean delivery under spinal anesthesia received benzathine penicillin G, 2.4 million units intramuscularly (IM) preoperatively. Ten women delivered 1 day after injection, five delivered 2-3 days after, and ten delivered 7 days after. We collected maternal serum and cerebrospinal fluid, amniotic fluid (AF), and cord serum at delivery. Penicillin levels were measured using a validated agar disc diffusion method (sensitivity 0.006 micrograms/mL) with Micrococcus lutea as the test organism. RESULTS: There was no significant difference in mean penicillin levels at day 1, day 2-3, or day 7 for maternal serum, maternal cerebrospinal fluid, cord serum, or AF. The mean (+/- standard error) penicillin concentration (range 0.005-0.59 micrograms/mL) in maternal serum declined from 0.14 +/- 0.04 micrograms/mL 1 day after injection to 0.08 +/- 0.06 micrograms/mL 7 days after injection. The proportion of patients with a penicillin concentration at or above 0.018 micrograms/mL in the maternal serum declined significantly from day 1 to day 7 (P = .03). Overall, nine of 25 women (36%) had serum penicillin levels that were less than 0.018 micrograms/mL. CONCLUSION: A wide range of penicillin levels were observed in gravidas at term in the maternal serum, cerebrospinal fluid, umbilical cord serum, and AF within 1 week after 2.4 million units of benzathine penicillin G IM. We speculate that altered pharmacokinetics may affect the efficacy of this drug for prevention of congenital syphilis in the near-term gestation.