小剂量多巴胺对肠系膜上动脉闭塞休克兔动脉血及门静脉血乳酸浓度影响的研究

Effects of lowdose dopamine on arterial and portal venous blood lactate concentrations in rabbits with superior mesenteric artery occlusion shock

目的：探讨肠系膜上动脉闭塞（ＳＭＡＯ）休克兔动脉血和门静脉血乳酸浓度的变化，以及小剂量多巴胺（５ μｇ·ｋｇ－ １·ｍ ｉｎ－ １）对其的影响。方法：２０只新西兰家兔随机分成２组，均制成ＳＭＡＯ 休克模型，２组均按３０ ｍ ｌ·ｋｇ－ １·ｈ－ １输入０．９％ ＮａＣｌ；Ａ组另给予多巴胺５ μｇ·ｋｇ－ １ ·ｍ ｉｎ－ １，Ｂ组作为对照组。分别观察血流动力学、动脉血和门静脉血乳酸浓度（ＡＬＴ、ＰＬＴ），以及腹腔组织氧供（ＳＤＯ２）、氧耗（ＳＶＯ２）和氧摄取率（ＳＯ２ＥＲ）的变化。结果：Ａ组门静脉血流量指数（ＱｐｖⅠ）在休克模型复制后６０、９０ 和１２０ 分钟时明显高于Ｂ组（Ｐ＜ ０．０５或Ｐ＜ ０．０１）；２ 组ＡＬＴ、ＰＬＴ均明显升高，以休克后０ 时为最高〔Ａ 组分别为（６．５±１．１）ｍ ｍ ｏｌ／Ｌ和（６．９±１．４）ｍ ｍ ｏｌ／Ｌ；Ｂ组分别为（６．４±０．８）ｍ ｍ ｏｌ／Ｌ和（６．８±１．２）ｍ ｍ ｏｌ／Ｌ〕，但Ａ 组在此后呈逐渐下降趋势，在１２０分钟时最低〔分别为（３．２±０．３）ｍ ｍ ｏｌ／Ｌ和（３．５±０．３）ｍ ｍ ｏｌ／Ｌ〕，而Ｂ组则呈持续高水平〔分别为（５．５±０．５）ｍ ｍ ｏｌ／Ｌ和（５．７±０．９）ｍ

Objective:To study the effects of lowdose dopamine(5 μg·kg -1 ·min -1 ) on arterial and portal venous blood lactate concentrations and splanchnic oxygenation.Methods:20 rabbits were randomly divided into two groups,group A with dopamine,group B as controls.Superior mesenteric artery occlusion (SMAO) shock model was induced in both groups.Hemodynamics,arterial and portal venous blood gas analysis and lactate concentrations,splanchnic oxygen delivery (SO 2),consumption (SO 2) and extraction (SO 2ER) were measured respectively.Results:Portal venous blood flow index (QpvI) was significantly higher in group A than that of group B at 60,90 and 120 minutes respectively following shock ( P <0 05 or P <0 01).Aterial and portal venous blood lactate concentrations were increased in two groups and peaked at 0 minute 〔group A:( 6 5±1 1)mmol/L and (6 9±1 4)mmol/L;group B:(6 4±0 8) mmol/L and (6 8±1 2)mmol/L〕,but they were decreased in group A after then,and reached a low value at 120 minutes 〔(3 2±0 3)mmol/L and (3 5± 0 3)mmol/L 〕.These values were higher in group B during shock 〔(5 5±0 5)mmol/L and (5 7± 0 9)mmol/L 〕,and significant differences were found between two groups at 60,90 and 120 minutes ( P <0 01).In addition,O 2 and O 2 were higher in group A than those in group B at 60,90 and 120 minutes respectively ( P <0 05 or P <0 01),but no significant difference in SO 2ER was noted between two groups (all P >0 05 ).Conclusions: LowO 2 and O 2 were higher in group A than those in group B at 60,90 and 120 minutes respectively ( P <0 05 or P <0 01),but no significant difference in SO 2ER was noted between two groups (all P >0 05 ).Conclusions: LowO 2 were higher in group A than those in group B at 60,90 and 120 minutes respectively ( P <0 05 or P <0 01),but no significant difference in SO 2ER was noted between two groups (all P >0 05 ).Conclusions: Lowdose dopamine could increase splanchnic blood perfusion,improve splanchnic oxygenation and decrease both arterial and portal venous blood lactate concentrations following SMAO shock .