以SvO_2为导向的早期目标导向液体治疗对感染性休克猪血流动力学和氧动力学的影响

The effect of SvO_2-guided early goal directed fluid therapy on hemodynamic and oxygen dynamics in septic shock pig model

目的评价以混合静脉血氧饱和度(Sv O_2)为导向的早期目标导向液体治疗(EGDT)对感染性休克猪血流动力学和氧动力学的影响。方法雄性巴马小型猪12只,采用随机数字表法均分为传统方法(C)组和目标导向(G)组。采用静脉输注内毒素方法制造感染性休克模型后,C组休克后维持平均动脉压(MAP)≥65 mm Hg,中心静脉压(CVP)8~12 mm Hg,尿量≥0.5 m L/(kg·h),G组除以上指标外,维持Sv O_2≥0.65。治疗持续6 h。分别在内毒素开始输注0、60、120、180、240、300、360、420及480 min(T0~T8)记录中心体温、血流和氧动力学指标及使用的液体和血管活性药物使用情况。结果与C组相比,在血流动力学方面2组各时点MAP、心率(HR)、全身血管阻力指数(SVRI)差异无统计学意义(P>0.05),G组在T4~T8时点心输出量指数(CI)和CVP升高(P<0.05),在T8时点平均肺动脉压(MPAP)和肺血管阻力指数(PVRI)降低(P<0.05);在氧动力学方面,G组在T3~T8时点Sv O_2升高,氧摄取率(O_2ER)降低(P<0.05),在T4~T8时点氧供(DO_2)升高(P<0.05),T5~T8时点血乳酸(Lac)降低,在T8时点动静脉CO_2分压差[Δp(CO_2)]降低(P<0.05),2组动物各时点氧耗(VO_2)差异无统计学意义(P>0.05)。G组补液量和尿量多,去甲肾上腺素量较少(P<0.05),G组多巴酚丁胺用量较多,而C组均未用。结论以Sv O_2为导向的EGDT在感染性休克救治中可更加有效地稳定血流动力学和氧动力学,表现为心输出量增加、氧供增加、氧摄取率正常、组织灌注较好。

Objective To evaluate the effect of Sv O_2-guided early goal directed fluid therapy on hemodynamic andoxygen dynamics in septic shock pig model.MethodsTwelve Bama miniature pigs(male, 21-24 kg) were equallyrandomized into 2 groups, group C and group G. Septic shock was induced by intravenous infusion endotoxin. Group Creceived hemodynamic support aiming central venous pressure at 8 to 12 mm Hg, urinary output 0.5 m L/kg per hour, andmean arterial pressure greater than 65 mm Hg. Group G maintained Sv O_2 greater than 0.65 in addition to the above indicators.The interventions lasted 6 h and at T0-T8(0, 60, 120, 180, 240, 300, 360, 420 and 480 min) recorded temperature,hemodynamic and oxygen dynamics indexes for each group, and recorded 6 hours for accumulated liquid volume, vascularactive drug, and changes of urine.ResultsThere were no significant differences in mean arterial blood pressure(MAP),heart rate(HR) and systemic vascular resistance index(SVRI) at each time point between group G and group C(P>0.05).Values of CI and CVP were increased at T4-T8 in group G(P<0.05). Values of MPAP and PVRI were decreased at T8 ingroup G(P<0.05). Values of Sv O_2 were increased at T3-T8, O_2 ER were decreased at T3-T8(P<0.05), DO_2 were increasedat T4-T8(P<0.05), Lac were decreased at T5-T8, and Δp(CO_2) was decreased at T8 in group G(P<0.05). There were nosignificant differences in values of VO_2 at T1-T8 between two groups(P>0.05). The amount of intravenous infusion andurine volume were more and the amount of norepinephrine was less in animals of group G(P<0.05). The dosage of dobutamine was more in animals of group G, and which was not used in animals of group C.ConclusionSvO_2 guided fluidtherapy is more effective than conventional treatment to stabilize hemodynamics and oxygen kinetics, which is characterizedby the increased cardiac output, increased oxygen supply, normal oxygen uptake rate and good tissue perfusion.