Nieminen K, Puolakka J
Department of Obstetrics and Gynecology, Middle Finland Central Hospital, Jyväskylä, Finland.
Acta Obstet Gynecol Scand. 1997 Jan;76(1):50-4. doi: 10.3109/00016349709047784.
To study whether paracervical block (PCB) with 12.5 mg (0.125%) of bupivacaine is as effective as with 25 mg (0.25%) and if there are differences in fetal heart rate (FHR) patterns between the doses.
A prospective, randomized double-blind study. Fifty-two patients received PCB with 25 mg and 45 patients with 12.5 mg of bupivacaine. Pain intensity was assessed by the patients on a horizontal visual analog scale (VAS). Fetal heart rates of the fetuses were analyzed visually concerning basal rate, variability, accelerations, bradycardia, silent pattern and decelerations.
The pain relief was statistically significant in both groups up to 120 min after PCB. The VAS-values were similar in both groups both before and after PCB. Fetal heart rate changes appeared in both groups more frequently after than prior to PCB. In patients receiving 25 mg of bupivacaine there appeared to be more FHR changes than in those receiving 12.5 mg.
Paracervical block with 12.5 mg of bupivacaine is an effective method to relieve pain during labor. Fetal heart rate changes seemed to appear less frequently with this reduced dose. It seems that by lowering the dose of bupivacaine it is possible to reduce fetal side-effects without losing analgesic effect.
研究12.5毫克（0.125%）布比卡因的宫颈旁阻滞（PCB）是否与25毫克（0.25%）的效果相同，以及不同剂量之间胎儿心率（FHR）模式是否存在差异。
一项前瞻性、随机双盲研究。52例患者接受25毫克布比卡因的PCB，45例患者接受12.5毫克布比卡因的PCB。患者通过水平视觉模拟量表（VAS）评估疼痛强度。对胎儿的心率进行视觉分析，包括基础心率、变异性、加速、心动过缓、静止模式和减速。
两组在PCB后120分钟内疼痛缓解均具有统计学意义。两组在PCB前后的VAS值相似。两组胎儿心率变化在PCB后比PCB前更频繁出现。接受25毫克布比卡因的患者似乎比接受12.5毫克的患者有更多的FHR变化。
12.5毫克布比卡因的宫颈旁阻滞是分娩时缓解疼痛的有效方法。使用这种较低剂量时，胎儿心率变化似乎出现得较少。似乎通过降低布比卡因的剂量，可以在不丧失镇痛效果的情况下减少胎儿副作用。
