Maternal, fetal, and neonatal effects of lidocaine with and without epinephrine for epidural anesthesia in obstetrics

The effects of epidural lidocaine with and without 1:300,000 epinephrine on uterine activity, progress of labor, fetal heart rate, maternal blood pressure and heart rate, newborn Apgar scores, neonatal acid-base status, and the Neurologic and Adaptive Capacity Scoring System were compared in 30 parturients during labor and delivery. Patients in group I (n = 16) received 1.5% lidocaine with 1:300,000 epinephrine and those in group II (n = 14) 1.5% lidocaine alone. Addition of epinephrine to lidocaine did not have any significant effects on uterine activity, duration of first or second stages of labor, fetal heart rate variability, or the incidence of abnormal fetal heart rate patterns. Maternal heart rate and the incidence of hypotensive episodes did not differ significantly between the two groups of patients. Apgar scores, neonatal acid-base status, and the NACS were equally good in the two groups. Duration of analgesia was significantly longer in group I as compared to group II patients (106.9 +/- 6.6 vs 66.2 +/- 4.4 min, P less than 0.001). Umbilical venous concentrations of lidocaine and umbilical vein to maternal vein ratios of lidocaine were significantly higher in group II patients (P less than 0.05). It is concluded that addition of epinephrine to lidocaine during epidural anesthesia in the normal parturient has no adverse effects on mother, fetus, neonate, or the progress of labor and it significantly prolongs the duration of anesthesia and limits the placental transfer of lidocaine.     

Comparative maternal, fetal, and neonatal effects of chloroprocaine with and without epinephrine for epidural anesthesia in obstetrics

The effects of epidural chloroprocaine with and without 1:200,000 epinephrine during labor and delivery on uterine activity, progress of labor, fetal heart rate, maternal blood pressure, newborn Apgar scores, neonatal acid-base status, and the Neurologic and Adaptive Capacity Scoring System (NACS) were compared in 28 parturients. Patients in group I (n = 14) received 2% chloroprocaine with 1:200,000 epinephrine and patients in group II (n = 14) received 2% plain chloroprocaine. Addition of epinephrine to chloroprocaine had no significant effects on uterine activity, duration of first or second stages of labor, or fetal heart parameters. Apgar scores, neonatal acid-base status, and the NACS were equally good in the two groups. Duration of analgesia was significantly longer in group I than in group II patients (76 +/- 3.8 vs 42.9 +/- 1 min, P less than 0.001). We conclude that addition of epinephrine to chloroprocaine during epidural anesthesia in the normal parturient has no adverse effects on mother, fetus, neonate, or the progress of labor and that it significantly prolongs the duration of anesthesia.     

Continuous infusion epidural analgesia in parturients receiving bupivacaine, chloroprocaine, or lidocaine--maternal, fetal, and neonatal effects

The effects of epidural analgesia for labor and delivery using a continuous infusion technique on fetal heart rate, uterine activity, maternal blood pressure, Apgar scores, neonatal acid-base status, and the Neurologic and Adaptive Capacity Scoring System were studied in 61 parturients. Group I (n = 23) received initial test and therapeutic doses of 2 and 6 ml of 0.5% bupivacaine followed by an infusion of 0.125% at a rate of 14 ml/hr. Group II (n = 19) received 2 and 6 ml of 2% chloroprocaine followed by an infusion of 0.75% at a rate of 27 ml/hr. Group III (n = 19) received 2 and 6 ml of 1.5% lidocaine followed by an infusion of 0.75% at a rate of 14 ml/hr. None of the three local anesthetics used had any significant effect on baseline fetal heart rate or uterine activity. In cases in which monitoring of fetal heart rate was both technically satisfactory and continuous, late and variable decelerations in fetal heart rate were seen in 10 of 17, 3 of 18, and 2 of 19 of the fetuses in groups I, II, and III, respectively. The incidence was significantly higher in group I than in groups II or III (P less than 0.05). Apgar scores and neonatal acid-base status were equally good in all three groups. Neurologic and adaptive capacity scores did not differ among the three groups of neonates, nor did any of the neonates in the three groups score lower than a control group of 19 neonates whose mothers did not receive any analgesia or medications for labor and delivery.(ABSTRACT TRUNCATED AT 250 WORDS)     

Fetal heart rate after epidural lidocaine and bupivacaine for elective cesarean section

This prospective double-blind study was designed to determine whether the fetal heart rate (FHR) changes that have been reported after epidural administration of bupivacaine and lidocaine during labor are present when larger doses of these drugs are given during elective cesarean section. Prior to inserting an epidural catheter, FHR and maternal vital signs were monitored during a control period in 60 healthy term parturients. Patients were randomly assigned to receive either 0.5% bupivacaine with 0.1 mEq sodium bicarbonate added to each 20 ml (n = 30) or 2% lidocaine with 1:300,000 epinephrine (n = 30). A 3-ml test dose of the study solution was injected via the catheter and was followed by an additional 17 ml, in increments; additional doses were administered as necessary to obtain surgical anesthesia. FHR and maternal vital signs were monitored for at least 20 min and the characteristics of the anesthetic block noted. At delivery, neonatal status was evaluated, and maternal and cord blood samples were obtained for local anesthetic assays and neonatal blood gases. The groups were similar with respect to maternal characteristics, onset of surgical anesthesia, time to delivery, and uterine incision-delivery interval. Maternal blood pressure decreased from control values in both groups (P less than 0.05), but there was no difference between the groups in either the incidence of hypotension or ephedrine requirements. Analysis of FHR tracings by a perinatologist blinded to the study group revealed no changes after anesthesia and no significant differences between the groups at any time in basal FHR, short- or long-term variability, or the incidence of accelerations or decelerations.(ABSTRACT TRUNCATED AT 250 WORDS)     

Abnormal echogenic findings detected by transesophageal echocardiography and cardiorespiratory impairment during total knee arthroplasty with tourniquet

BACKGROUND: The minimum local analgesic concentration (MLAC) has been defined as the median effective local analgesic concentration in a 20-ml volume for epidural analgesia in the first stage of labor. The aim of this study was to determine the local anesthetic-sparing efficacy of epidural epinephrine by its effect on the MLAC of bupivacaine. METHODS: In this double-blind, randomized, prospective study, 70 parturients who were at 7 cm or less cervical dilation and who requested epidural analgesia were allocated to one of two groups. After lumbar epidural catheter placement, 20 ml bupivacaine (n = 35) or bupivacaine with epinephrine 1:300,000 (n = 35) was administered. The concentration of bupivacaine was determined by the response of the previous patient in that group to a higher or lower concentration using up-down sequential allocation. Analgesic efficacy was assessed using 100-mm visual analog pain scores, with 10 mm or less within 30 min defined as effective. RESULTS: The MLAC of bupivacaine alone was 0.091% wt/vol (95% confidence interval, 0.081-0.102). The addition of epinephrine 1:300,000 (66.7 microg) resulted in a significant reduction (P < 0.01) in the MLAC of bupivacaine to 0.065% wt/vol (95% confidence interval, 0.047-0.083). The lowest maternal blood pressure was significantly lower in the bupivacaine-epinephrine group (P = 0.03). There were statistically significant reductions in fetal heart rate (P = 0.011) in the bupivacaine-epinephrine group that were not clinically significant. CONCLUSIONS: The addition of epidural epinephrine 1:300,000 (66 microg) resulted in a significant 29% reduction in the MLAC of bupivacaine. Coincident reductions in fetal heart rate and maternal blood pressure were also observed that were not clinically significant.     

Effect of standard diluted epinephrine infusion on epidural anesthesia in labor

BACKGROUND AND OBJECTIVES: Epinephrine is used with local anesthetics to prolong the duration of epidural analgesia and decrease the peak plasma concentrations of local anesthetics. However, the duration of labor may be prolonged because epinephrine reduces uterine activity. We designed a prospective, randomized, and doubleblind study to examine the effects of epinephrine infusion on the quality of analgesia and plasma concentration of local anesthetic, as well as the effect on the uteroplacental circulation, duration of the first or second stage of labor, and fetal outcome. METHODS: Twenty-four parturients received continuous epidural bupivacaine 0.125% (8 mL/h) combined either with epinephrine (40 microg/h) (n = 12) or without epinephrine (n = 12) for analgesia during labor. If patients requested additional analgesia, a bolus of 1% or 1.5% lidocaine (6 to 10 mL) was given. RESULTS: Only the plain bupivacaine group required additional lidocaine. However, epinephrine infusion prolonged the median (range) duration of the second stages of labor: 69 (21 to 231) minutes with epinephrine group versus 31 (8 to 99) minutes without epinephrine group (P < .05), and decreased pH in umbilical artery at the time of delivery. Epinephrine infusion did not change the uterine and umbilical blood flow, which were determined as the resistance indices. Changes in the fetal heart rate and Apgar score were also comparable. Epinephrine significantly reduced the umbilical venous to maternal arterial bupivacaine concentration (P < .05). CONCLUSIONS: A standard diluted epinephrine infusion (40 microg/h) into epidural space decreased anesthetic requirements. The possibility of the prolonged duration of labor remains a problem.     

Epidural anesthesia worsens uterine blood flow and fetal oxygenation during hemorrhage in gravid ewes.

Recent studies suggest that epidural anesthesia initiated before hemorrhage may improve survival and acid-base status in laboratory animals. However, studies of hemorrhagic shock in nonpregnant animals may not be applicable to less severe hemorrhage in pregnant animals. The purpose of this study was to determine whether epidural anesthesia alters maternal and fetal hemodynamic and acid-base responses to hemorrhage in gravid ewes. Twenty-four experiments were performed in twelve chronically instrumented animals between 0.8 and 0.9 of timed gestation. The experimental sequence included: 1) T = 0 min: normal saline 500 ml intravenously; 2) T = 15 min: epidural administration of 0.5% bupivacaine (epidural group) or normal saline (control group); 3) T = 30 min: epidural administration of additional 0.5% bupivacaine (epidural group only) if the sensory level of anesthesia was below T10; 4) T = 45 min: maternal hemorrhage 20 ml/kg over 55 min; and 5) T = 110 min: transfusion of collected maternal blood over 55 min. At 45 min (i.e., 30 min after the epidural injection of bupivacaine), epidural bupivacaine resulted in a median sensory level of T9 in the epidural group. At that time, maternal mean arterial pressure was less (P less than 0.05) in the epidural group than in the control group (14 +/- 2% below baseline versus 4 +/- 1% above baseline, respectively). Maternal mean arterial pressure, heart rate, cardiac output, and uterine blood flow, and fetal PO2 and pH all were significantly less during hemorrhage (P less than 0.05) in the epidural group than in the control group.(ABSTRACT TRUNCATED AT 250 WORDS)     

Fetal heart rate abnormalities after regional analgesia for labor pain: the effect of intrathecal opioids

BACKGROUND AND OBJECTIVES: Intrathecal opioids used to relieve labor pain have been associated with uterine hyperactivity and nonreassuring fetal heart rate abnormalities. We retrospectively evaluated all charts of singleton, term, vertex-presenting parturients in active labor requesting neuraxial pain relief during a 1-year period for the occurrence of nonreassuring fetal heart rate tracings. METHODS: Three different strategies to relieve labor pain were routinely used in our department: conventional epidural using 10 mL bupivacaine 0.125% and sufentanil 0.75 microg/mL; combined spinal and epidural (CSE) using intrathecal sufentanil (7.5 microg); and CSE using intrathecal bupivacaine (2.5 mg) and sufentanil (1.5 microg). Charts (n = 1,293) were evaluated for nonreassuring fetal heart tracings and uterine hyperactivity as well as for neonatal and labor outcome. RESULTS: Intrathecal sufentanil (7.5 microg) produced significantly more nonreassuring tracings and uterine hyperactivity. However, this did not result in more cesarean deliveries or detrimental neonatal outcome. CONCLUSION: Based on this retrospective analysis, we conclude that intrathecal sufentanil in a dose of 7.5 microg has the potential to result in more nonreassuring fetal heart rate tracings compared with both intrathecal analgesia using a bupivacaine (2.5 mg)/sufentanil (1.5 microg) mixture and epidural analgesia using bupivacaine, sufentanil, and epinephrine. Reg Anesth Pain Med 2001;26:257-262.     

Epidural anesthesia with plain bupivacaine 0.75% for elective caesarean section

The clinical effects of epidural anesthesia with bupivacaine 0.75% for elective caesarean section were investigated in 20 healthy pregnant women. The mean total dose of bupivacaine which offers sufficient sensory and motor block, provided the epidural catheter is properly placed, was 137.5 mg. Maternal hypotension occurred in 4 patients in spite of prehydratation and left uterine displacement. No maternal systemic toxicity or local neurotoxicity was found. The results of the Apgar scoring and the neonatal acid-base studies showed that there is no clinically important neonatal depression with this technique.     

Intrathecal sufentanil and fetal heart rate abnormalities: a double-blind, double placebo-controlled trial comparing two forms of combined spinal epidural analgesia with epidural analgesia in labor

Combined spinal epidural analgesia (CSE) for labor pain relief has become increasingly popular. However, the effect of intrathecal sufentanil on the incidence of uterine hyperactivity and fetal heart rate (FHR) abnormalities remains controversial. We hypothesized that the use of intrathecal sufentanil in a dose of 7.5 microg is more likely to induce a nonreassuring FHR tracing than a small dose of spinal sufentanil combined with bupivacaine or epidural analgesia. Three-hundred parturients were randomized into three groups. In the first group, epidural analgesia was initiated with 12.5 mg of bupivacaine, 12.5 microg of epinephrine, and 7.5 microg of sufentanil in a volume of 10 mL (EPD group). In Group 2, initial intrathecal analgesia consisted of 2.5 mg of bupivacaine, 2.5 microg of epinephrine, and 1.5 microg of sufentanil (BSE group); in Group 3, spinal analgesia consisted of 7.5 microg of sufentanil (SUF group). Analgesia was maintained in all groups with patient-controlled epidural analgesia using bupivacaine 0.125%, 1.25 microg/mL of epinephrine, and 0.75 microg/mL of sufentanil (bolus, 4 mL; lockout, 15 min). Cardiotocography was monitored continuously 15 min before analgesia and for 60 min after the start of analgesia. The quality of analgesia, labor, and neonatal outcome and side effects were recorded. Twenty-four percent of patients in the SUF group developed FHR abnormalities (bradycardia or late decelerations) during the first hour after initiation of analgesia compared with 12% in the BSE group and 11% in the EPD group. Uterine hyperactivity occurred in 12% of parturients in the SUF group but in only 2% in the other groups. Onset of analgesia was more rapid in both CSE groups as compared with the EPD group. However, 29% of patients in the BSE group developed severe hypotension, requiring IV ephedrine (29% in the BSE group versus 7% and 12% in the EPD and SUF groups, respectively). All these differences reached statistical significance. The present data corroborate previous recommendations of caution when performing CSE using a large dose (7.5 microg or more) of spinal sufentanil because of the risk of uterine hyperactivity and FHR abnormalities. IMPLICATIONS: Combined spinal epidural analgesia (CSE) produces pain relief during labor. Fetal heart rate changes after CSE using intrathecal sufentanil have been reported. We performed a randomized, blinded trial confirming that fetal heart rate changes are more frequent after CSE using 7.5 micro g of intrathecal sufentanil as compared with other forms of neuraxial labor analgesia.     

Epinephrine enhances analgesia produced by epidural bupivacaine during labor

Reports on the analgesic and hemodynamic effects of epinephrine added to bupivacaine for epidural use in obstetrics are conflicting. In this study, healthy parturients received in a random manner either 10 ml of 0.25% bupivacaine (n = 50) or 10 ml of 0.25% bupivacaine with 1:300,000 epinephrine (n = 50) epidurally. Epinephrine enhanced the analgesia produced by bupivacaine: onset was hastened (5.8 +/- 0.6 vs 8.7 +/- 0.8 min, mean +/- SEM, P less than 0.05), duration prolonged (123 +/- 7.0 vs 92 +/- 5.0 min, P less than 0.05), and the number of women requiring additional local anesthetic for analgesia decreased (9 vs 18, P less than 0.05) compared to the group receiving plain bupivacaine. The incidence of hypotension did not differ between groups. Maternal heart rate increased only after injection of the epinephrine-containing solution. The authors conclude that epinephrine 1:300,000 modestly but statistically significantly improves the analgesic efficacy of epidurally administered 0.25% bupivacaine during labor.     

Effect of epidural epinephrine infusion with bupivacaine on labor pain and mother-fetus outcome in humans

BACKGROUND AND OBJECTIVES: Epinephrine is used with local anesthetics to prolong the duration of epidural analgesia and decrease the peak plasma concentrations of local anesthetics. In the practice of obstetric anesthesia, the utero-placental and fetal effects of epinephrine are controversial issues. We designed a prospective, randomized, and double-blind study to examine the effects of epinephrine infusion on the quality of analgesia and uterine or umbilical blood flows with Doppler ultrasound, as well as the duration of the first or the second stage of labor, and fetal outcome. METHODS: Twenty-eight parturients received continuous epidural bupivacaine 0.25% (4 mL/h) combined either with epinephrine (20 microg/h) (n = 13) or without epinephrine (n = 15) for analgesia during labor. If patients requested additional analgesia, an additional bolus of 1% or 1.5% lidocaine (6 to 10 mL) was administered. RESULTS: The total amount of additional lidocaine was greater in the plain bupivacaine group (130 [0, 280] mg; median [25th, 75th percentile] with P < .05) than in the epinephrine group (0 [0, 60] mg). Epinephrine infusion did not alter the resistance of the uterine and umbilical arteries as measured by resistance index. The duration of the first or second stages of labor did not significantly differ in the 2 groups. Epinephrine infusion did not change the fetal heart rate or the blood gas data in the umbilical artery. CONCLUSIONS: A low-dose epidural infusion of epinephrine decreased anesthetic requirements.     

Effect of Epidural Epinephrine on the Minimum Local Analgesic Concentration of Epidural Bupivacaine in Labor

Background: The minimum local analgesic concentration (MLAC) has been defined as the median effective local analgesic concentration in a 20-ml volume for epidural analgesia in the first stage of labor. The aim of this study was to determine the local anesthetic-sparing efficacy of epidural epinephrine by its effect on the MLAC of bupivacaine.

Methods: In this double-blind, randomized, prospective study, 70 parturients who were at 7 cm or less cervical dilation and who requested epidural analgesia were allocated to one of two groups. After lumbar epidural catheter placement, 20 ml bupivacaine (n = 35) or bupivacaine with epinephrine 1:300,000 (n = 35) was administered. The concentration of bupivacaine was determined by the response of the previous patient in that group to a higher or lower concentration using up-down sequential allocation. Analgesic efficacy was assessed using 100-mm visual analog pain scores, with 10 mm or less within 30 min defined as effective.

Results: The MLAC of bupivacaine alone was 0.091% wt/vol (95% confidence interval, 0.081-0.102). The addition of epinephrine 1:300,000 (66.7 [mu]g) resulted in a significant reduction (P < 0.01) in the MLAC of bupivacaine to 0.065% wt/vol (95% confidence interval, 0.047-0.083). The lowest maternal blood pressure was significantly lower in the bupivacaine-epinephrine group (P = 0.03). There were statistically significant reductions in fetal heart rate (P = 0.011) in the bupivacaine-epinephrine group that were not clinically significant.     

Anaesthetic technique for elective caesarean section and neurobehavioural status of newborns

Ninety healthy parturients undergoing elective caesarean section were randomly allocated to receive either general (n = 30), epidural (n = 30) or spinal (n = 30) anaesthesia. Acid-base status, Apgar score and neurobehavioural status, using the neurologic and adaptive capacity scoring (NACS) system, were studied in the newborn. Apgar scores and acid-base parameters were similar in all the three groups. NACS testing revealed significantly more vigorous babies in the spinal anaesthesia group than in the other two groups at 15 min and 2 h interval after delivery, despite a higher incidence of maternal hypotension. We conclude that newborns tend to have a better neurobehavioural status in the early post-delivery period if their mothers receive spinal anaesthesia rather than general or epidural anaesthesia for caesarean section.     

Maternal and fetal effects of epinephrine in gravid ewes

Intravenous cannulation by an epidural catheter may complicate epidural anesthesia. Local anesthetic solutions containing epinephrine produce tachycardia and hypertension when given intravenously and may identify intravenous placement. The authors studied the maternal and fetal effects of intravenous epinephrine-containing solutions in ten chronically instrumented gravid ewes. While continuously monitoring maternal and fetal effects, epinephrine 5, 10, or 20 micrograms iv bolus was injected. Solutions of bupivacaine 5 mg and bupivacaine 5 mg combined with epinephrine 10 micrograms given iv were also examined. All epinephrine-containing solutions produced a significant increase (P less than 0.001) in maternal mean arterial pressure, which returned to baseline after 1 min. Maternal heart rates decreased transiently and returned to baseline after 1 min. All epinephrine-containing solutions decreased uterine blood flow (UBF) (P less than 0.001), and, for doses of 10 to 20 micrograms, this decrease lasted more than 3 min. Fetal heart rate and mean arterial blood pressure did not change following any test solution, nor did maternal or fetal arterial blood gas values. The authors conclude that small intravenous boluses of epinephrine decreased UBF in these animals.     

Neonatal responses to alphaprodine administered during labor

The effect of intravenously administered alphaprodine on newborn Apgar scores, neonatal acid-base status, and the Neurologic and Adaptive Capacity Scoring System (NACS) were compared in 30 parturients. Patients in group 1 (n = 15) received 20-40 mg increments of alphaprodine, with a total dose of 39.3 +/- 3.7 mg (mean +/- SEM). Group 2 patients (n = 15) received no medication during labor. Apgar scores, neonatal acid-base status, and the NACS were equally good in the two groups. The concentrations of alphaprodine in maternal vein, umbilical vein, and umbilical artery at delivery were measured using a gas-chromographic mass spectrophotometric technique. The results showed an umbilical vein-to-maternal vein ratio of 0.52 +/- 0.09. It is concluded that when administered as in this study, alphaprodine has no adverse effects on the neonate.     

Transient maternal hypotension following epidural anesthesia

Transient maternal hypotension following regional anesthesia can lead to significantly lower umbilical cord pH values. Although this acidosis has not been found to be clinically significant, acidosis may increase the placental transfer of local anesthetic agents as a result of "ion trapping." The purpose of this study was to examine the pharmacologic and clinical consequences of transient maternal hypotension following epidural anesthesia with 0.5% bupivacaine before cesarean section. Patients were divided into two groups based on the development of maternal hypotension, defined as a systolic blood pressure less than 100 torr or a decrease of 30% or more from the preanesthetic level. Thirteen patients (33%) developed hypotension that was corrected within 2.1 +/- 1.8 min. The pH of umbilical cord venous and arterial blood and the concentration of bupivacaine were significantly lower (P less than 0.05) in neonates of mothers in the hypotensive group than in neonates of mothers that did not develop hypotension. The results show, however, that transient maternal hypotension following epidural anesthesia does not lead to a greater placental transfer of bupivacaine due to "ion trapping" even though neonatal cord blood pH decreases.     

程控硬膜外间歇脉冲注入与持续背景输注用于分娩镇痛的比较

目的比较程控硬膜外间歇脉冲注入(programmed intermittent epidural bolus,PIEB)和持续背景输注(CEI)两种模式联合PCEA用于分娩镇痛的临床效果。方法自愿接受分娩镇痛足月、单胎和头位初产妇200例,随机分为两组,每组100例。在宫口扩张2~3 cm时采用硬膜外阻滞行分娩镇痛。PIEB组背景输注剂量为8 ml/h,给药速度为6 ml/min,每小时给药一次;CEI组以8ml/h的速度持续给药。观察产妇镇痛前(T0)、镇痛后10 min(T1)、30 min(T2)、1 h(T3)、2 h(T4)、宫口开全时(T5)、分娩时(T6)、分娩后1 h(T7)BP、VAS评分、改良Bromage评分;PCEA追加次数、罗哌卡因、舒芬太尼的用量、宫缩情况、胎心率、产程时间、镇痛时间、分娩方式、产妇使用催产素、不良反应、新生儿Apgar评分、产妇满意度评分。结果 T4~T6时PIEB组VAS评分明显低于CEI组(P0.01)。PIEB组PCEA追加次数、药物用量明显少于CEI组(P0.05),PIEB组产妇满意度明显高于CEI组(P0.05)。两组产妇的血压、宫缩持续时间和间隔时间、胎心率、产程、镇痛时间、分娩方式、使用催产素比例、不良反应发生率及新生儿Apgar评分差异无统计学意义。结论与采用CEI+PCEA模式比较,PIEB+PCEA模式的PCEA追加率更低、用药量更少、VAS评分更低、产妇的满意度更高,而不良反应并没有增加。     

曲马多对母婴乳酸盐和新生儿神经行为的影响

目的　研究曲马多对母婴血乳酸盐和新生儿神经行为与适应能力评分 (NACS)的影响。方法　 6 0例足月妊娠剖宫产产妇随机分三组 :T0 组 ,2 0例 ,肌注 0 9%氯化钠 2ml;T1组 2 0例 ,肌注曲马多 1 5mg/kg ;T2 组 ,2 0例 ,肌注曲马多 2mg/kg。各组肌注后开始麻醉 ,三组均采用脊麻与硬膜外联合阻滞。观察指标 :新生儿生后 15min的Apgar评分及新生儿生后 15min的NACS ;胎儿娩出时采脐动、静脉血和母体动脉血各 2ml,行血乳酸值测定及血气分析。结果　三组新生儿Apgar评分无明显差异 ,T0 组NACS明显高于T1组 (P <0 0 5 )和T2 组 (P <0 0 1) ;T2 组脐动、静脉血乳酸值明显高于T1组 (P <0 0 5 )和T0 组 (P <0 0 1) ;母体乳酸值三组间无明显差异 ;T2 组母体和脐动、静脉血PaCO2 明显高于T0 组 (P <0 0 1) ,T2 组脐动、静脉血SaO2 明显低于T0 组 (P <0 0 5 )。结论　剖宫产术前肌注曲马多 1 5mg/kg对新生儿无明显不良影响。但 2mg/kg曲马多肌注具有呼吸抑制作用 ,使脐动、静脉血乳酸盐增加 ,对新生儿NACS有一过性影响     

Spinal versus epidural anesthesia for cesarean delivery in severe preeclampsia: a prospective randomized, multicenter study

In this randomized, multicenter study we compared the hemodynamic effects of spinal and epidural anesthesia for cesarean delivery in severely preeclamptic patients. The epidural group (n = 47) received 2% lidocaine with epinephrine 1:400,000, 18-23 mL, followed by 3 mg of morphine after delivery. The spinal group (n = 53) received 2.2 mL of 0.5% hyperbaric bupivacaine plus 0.2 mg morphine. We hypothesized that the lowest MAP (mean arterial blood pressure, the primary outcome) during the delivery period would have to be at least 10 mm Hg less in the spinal group to be of clinical importance. We found that there was a statistically significant difference in MAP, with more patients in the spinal group exhibiting hypotension (P < 0.001). Although the incidence of hypotension (systolic arterial blood pressure, SAP < or =100 mm Hg) was more frequent in the spinal group than in the epidural group (51% versus 23%), the duration of significant hypotension (SAP < or =100 mm Hg) was short (< or =1 min) in both groups. There was more use of ephedrine in the spinal group than in the epidural group (median, 6 versus 0 mg) but hypotension was easily treated in all patients. Neonatal outcomes assessed by Apgar scores and the umbilical arterial blood gas analysis were similar in both groups. Adverse neonatal outcomes (5-min Apgar score < 7 and umbilical arterial blood pH < 7.20) were found in only 2 premature newborns (weight < 1500 g) who were born without maternal hypotension after regional anesthesia. We conclude that the results of this large prospective study support the use of spinal anesthesia for cesarean delivery in severely preeclamptic patients.