妊娠对大鼠布比卡因脊麻效力的影响

目的 探讨妊娠对大鼠布比卡因脊麻效力的影响.方法 雌性SD大鼠,非孕鼠体重180～220 g,孕鼠(孕17 d)体重350～400 g.取鞘内置管成功的非孕鼠及孕鼠各18只,非孕鼠随机分为3组(n=6):正常对照组(C组)、2%布比卡因组(B2组)及4%布比卡因组(B4组);孕鼠随机分为3组(n=6):对照组(PC组)、2%布比卡因组(PB2组)及4%布比卡因组(PB4组).C组与PC组:鞘内注射生理盐水30μl,其余4组相应鞘内分别注入2%或4%布比卡因30μl.分别于给药前(基础状态)、给药后10 min、20 min、30 min、1h、2 h、4 h、1 d、2 d、3 d和4 d时测定甩尾反应潜伏期,计算最大镇痛效应百分比(MPE);并进行后肢运动功能(MF)评分.结果 与基础值比较,B2组于给药后10 min～2 h时MPE升高,给药后10 min～1 h时MF评分升高;B4组于给药后10 min～4 h时MPE升高,给药后10 min～1 h时MF评分升高;PB2组于给药后10 min～1 d时MPE升高,给药后10 min～2 h时MF评分升高;PB4组于给药后10 min～1 d时MPE升高,给药后10 min～4 h时MF评分升高(P＜0.05).结论 妊娠可增加大鼠布比卡因脊麻的效力.

Effect of pregnancy on potency of bupivacaine for spinal anesthesia in rats

Objective To investigate the effect of pregnancy on the potency of bupivacaine for spinal anesthesia in rats. Methods Female non-pregnant SD rats weighing 180-220 g and 17 day pregnant SD rats weighing 350-400 g were used in this study. The rats ( 18 non-pregnant, 18 pregnant) in which PE-10 catheter were successfully placed without complications were selected. The 18 non-pregnant rats were randomly divided into 3 groups (n =6 each): control group (group C), 2% bupivacaine group (group B2 ) and 4% bupivacaine group (group B4). The 18 pregnant rats were also randomly divided into 3 groups (n = 6 each): control group (group PC),2% bupivacaine group (group PB2 ) and 4% bupivacaine group (group PB4 ). Group C and PC received intrathecal (IT) normal saline 30 μl, and the other 4 groups received 2% or 4% bupivacaine 30 μl intrathecally. Analgesia was determined using the taifllick latency (TFL) before IT administration (baseline), and at 10 min, 20 min,30 min, 1 h, 2 h, 4 h, 1 d, 2 d, 3 d and 4 d after IT administtation. The percentage of the maximal possible effect (MPE) was calculated. Hind-limb motor function (MF) was also assessed. Results Compared with the baseline value, MPE at 10 min-2 h after administration and MF scores at 10 min-1 h after administration were significantly increased in group B2, MPE at 10 min-4 h after administration and MF scores at 10 min-1 h after administration were significantly increased in group B4;MPE at 10 min-1 d after administration and MF scores at 10 min2 h were significantly increased in group PB2 and MPE at 10 min-1 d after administration and MF scores at 10 min4 h were significantly increased in group PB4 ( P ＜ 0.05 ). Conclusion Pregnancy can enhance the potency of bupivacaine for spinal anesthesia in rats.