规模化分娩镇痛的可行性

Feasibility of labour analgesia on a large scale

目的 评价规模化开展分娩镇痛的可行性。方法 自愿接受分娩镇痛及无产科及麻醉禁忌证的足月孕初产妇819例,全部采用腰麻-硬膜外联合镇痛(CESA)和病人自控镇痛(PCEA)的分娩镇痛法。进入活跃期时,蛛网膜下腔注射0.2％罗哌卡因3mg后30min,PCEA输注0.1％罗哌卡因与2μg/mg芬太尼的混合液,按PCA 6ml/15min,或持续背景速度9ml/h,按需追加3ml/h,于宫口开全停泵。结果 CSEA后VAS从镇痛前的(84.2±13.3)分迅速降至(5.4±6.4)分,且差异具有非常显著性(P<0.01)。PCEA总量0-117ml(25±17)ml;罗哌卡因(11.9±4.7)ml/h;芬太尼(23.8±9.4)μg/h;整个产程VAS评分0-40分,镇痛总有效率为96.1％。99.1％镇痛后Bromage标准0级,可下地行走。分娩镇痛率为32.7％,其中剖宫产率26.7％,低于同期的45.4％总剖宫产率;器械助产率为11.6％略高于同期9.3％的总器械助产率。低血压发生率为4.7％、恶心0.6％、皮肤瘙痒0.5％,产后头痛0.4％和尿潴留0.6％。结论CSEA+PCEA和罗哌卡因的使用,可有效降低剖宫产率,增加自然分娩率,并产生极少不良反应和最小的运动神经阻滞,对母婴安全有益。但观念的更新及分娩镇痛服务体系的建立更重要。

Objective To evaluate the feasibility of using labour analgesia on a large scale.Methods 819 primigravidae at full term requesting labour analgesia in early labour were enrolled in this study. With written consent combined spinal-epidural analgesia (CSEA) was performed at L2-3 interspace when their cervical dilatation was (3.1·0.6)cm. 0.2% ropivacaine 3 mg (1.5 ml) was injected into subarachnoid space. Epidural catheter was advanced cephalad for 4 cm and connected to PC A pump. A mixture of ropivacaine 0.1% and fentanyl 2 μg/ ml was used for PCEA. Thirty min after intrathecal injection PCEA was commenced. The patients were allocated to one of two PCEA regimen: in PCEA regimen-1 the bolus dose was 6 ml with a 15 min lockout interval and no background infusion and in PCEA regimen-2 the bolus dose was 3 ml with a 15 min lockout interval and background infusion at 9 ml/h. The following were recorded: (1) pain intensity evaluated using VAS(0-100), (2)motor block assessed using Bromage scale, (3) onset of analgesia after subarachnoid injection, (4) fetal heart rate, (5)maternal vital signs (ECG, BP,SpO2, RR), (6) Apgar score,(7)labour process, (8) mode of delivery and (9) the total amount of analgesics consumed. In 15 parturients blood samples were taken from maternal vein when the os was completely dilated and from umbilical vein for determination of plasma fentanyl concentration. Results 819 parturients received labour analgesia accounting for 32.6% of the total parturients in active labour(2510) during the same period (August 2001-August 2002). Their mean age( 28.3±2.0) years, body weight (72.3±3.5) kg and height (162.6±2.5) cm. The onset time of analgesia after intrathecal ropivacaine administration was 3-5min (4.1±0.5) min. The height of the block was T5-1(T9 2±0. 5). VAS was reduced from 84.2±13.3 before spinal analgesia to 5.4 ± 6.4 and spinal analgesia was maintained for 30-50 min. Total duration of analgesia (intrathecal + PCEA) was (229±98) min and the duration of PCEA was (199± 98) min. The amount of ropivacaine and fentanyl mixture consumed was 0-117 ml (25± 17) ml. In 32 parturients PCEA was inadequate and additional epidural 0.2% ropivacaine 5-10 ml was given. The success rate of labour analgesia was 96.1 % . The duration of the first stage of labour process was (527±174)min and of second stage (64±33)min. The rate of spontaneous delivery was 61.7% . The rate of cesarean section was 26.7% , lower than the total rate of cesarean section (45.4 % ) during the same period. The rate of instrumental delivery was 11.6% (the total rate of instrumental delivery was 9.25%) . Trace of fentanyl was detected in 5 blood samples from mothers and 2 umbilical blood samples. Apgar score at 1st rain was > 9 and at 5 th min was 10. The incidence of hypotension after spinal anesthesia was 4.7% (38 cases) . The incidence of nausea was 0.6% and of pruritus was 0.5% . Three patients developed postoperative headache (0.4%) and 5 patients developed urinary retention (0.6%) .Conclusion CSEA with ropivacaine is an effective technique for labour analgesia with minimal motor block and less adverse effects. The rate of cesarean section can also be reduced. It is safe for both mother and neonate and can be used on a large scale for labour analgesia.