急性呼吸窘迫综合征时足三里穴及相关脏腑 组织氧分压变化的实验研究

摘要

目的 观察急性呼吸窘迫综合征(ARDS)时经穴组织及相关脏腑组织氧分压变化的特点,阐明ARDS局部组织氧合情况与全身氧合情况的相关性及经穴组织和相关脏腑氧代谢的相关性.方法 选择健康新西兰大白兔20只,按随机数字表法分为ARDS模型组和对照组,每组10只.采用颈静脉注射油酸(0.08~ 0.1 mL/kg)的方法复制ARDS动物模型;对照组仅行气管切开、机械通气、动/静脉置管等操作而不给予油酸.用组织氧测定仪测定吸入氧浓度(FiO2)分别为0.21和1.00时两组足三里穴内、胃和肝组织的氧分压(PtO2),同时行动脉血和混合静脉血血气分析,计算氧摄取率(O2ER).结果 FiO2 0.21时ARDS模型组足三里穴内、胃和肝PtO2均明显高于对照组,动脉血氧分压(PaO2)、混合静脉血氧分压(PvO2)、动脉血氧饱和度(SaO2)、混合静脉血氧饱和度(SvO2)、O2ER均明显低于同期对照组.FiO2 1.00时两组足三里穴内、胃和肝PtO2及PaO2、SaO2、O2ER均较FiO2 0.21时升高,以ARDS模型组足三里穴内、胃和肝PtO2、O2ER水平升高更显著〔PtO2(kPa):足三里穴内:16.75±2.12比13.80±1.83,胃:16.45±1.33比13.35±1.25,肝:16.43±1.45比13.45±1.36, O2ER:(36.14±0.97)%比(30.81±1.01)%〕,PaO2、SaO2、SvO2以对照组升高更显著〔PaO2(mmHg,1 mmHg= 0.133 kPa):682.02±50.32比159.32±40.17,SaO2:1.00±0.00比0.98±0.01,SvO2:0.69±0.01比0.63±0.03,均P<0.05〕.与本组FiO2 0.21时比较,ARDS模型组FiO2 1.00时PvO2升高,对照组则降低,ARDS模型组和对照组比较差异有统计学意义(mmHg:36.00±2.83比42.50±1.70,P<0.05).且足三里穴内和胃PtO2呈正相关(r=0.963,P<0.001).结论 ARDS时在全身性氧输送障碍情况下,脏腑组织氧需求显著增加,但氧利用明显障碍,这可能与细胞线粒体功能障碍有关.经穴组织与相关脏腑组织氧分压有很好的相关性,经穴组织氧测定对脏腑组织氧代谢监测有重要的指导意义.%Objective To observe the characteristics of changes in tissue oxygen partial pressure in Zusanli (ST36) acupoint and related organs in acute respiratory distress syndrome (ARDS), and to clarify the correlation between oxygenation of local tissue and systemic oxygenation and the correlation between oxygen metabolism of acupoint tissues and related organ tissues.Methods Twenty healthy New Zealand white rabbits were selected and divided into an ARDS model group and a control group, according to random number table method, 10 in each group. Oleic acid (0.08 - 0.1 mL/kg) intravenous injection was used to replicate the ARDS animal model. Only tracheotomy, mechanical ventilation, insertion of arterial/venous catheter, etc other manipulations were conducted, and no oleic acid was injected in the control group. Tissue oximeter was used to determine the fraction of inspired oxygen (FiO2), when FiO2 was 0.21 and 1.00 respectively, the tissue oxygen partial pressure (PtO2) in Zusanli acupoint, stomach and liver was measured. Meanwhile, the blood gas analyses of arterial blood and mixed venous blood were carried out to calculate the oxygen extraction rate (O2ER).Results When FiO2 was equal to 0.21, the levels of PtO2 in Zusanli acupoint, stomach and liver of the ARDS model group were significantly higher than those of the control group in the same period; the partial pressure of oxygen arterial blood (PaO2), partial pressure of oxygen in mixed venous blood (PvO2), arterial oxygen saturation (SaO2), mixed venous oxygen saturation (SvO2) and O2ER of the ARDS model group were significantly lower than those of the control group over the same period. When FiO2 was equal to 1.00, PtO2, PaO2, SaO2 and O2ER in Zusanli acupoint, stomach and liver were increased compared with those when FiO2 was 0.21 in both groups, and the increase of PtO2 and O2ER in Zusanli acupoint, stomach and liver was more significant in the ARDS model group [PtO2 (kPa): Zusanli acupoint: 16.75±2.12 vs. 13.80±1.83, stomach: 16.45±1.33 vs. 13.35±1.25, liver: 16.43±1.45 vs. 13.45±1.36, O2ER: (36.14±0.97)% vs. (30.81±1.01)%]; the increase of PaO2, SaO2 and SvO2 was more significant in the control group [PaO2 (mmHg, 1 mmHg = 0.133 kPa): 682.02±50.32 vs. 159.32±40.17, SaO2: 1.00±0.00 vs. 0.98±0.01, SvO2: 0.69±0.01 vs. 0.63±0.03, allP < 0.05]. The indexes under FiO2 0.21 compared to those under FiO2 1.00 in the same group, it was shown that when FiO2 1.00, PvO2 was increased in the ARDS model group, but decreased in the control group, the difference between the two groups being statistically significant (mmHg: 36.00±2.83 vs. 42.50±1.70,P < 0.05). Besides, PtO2 in Zusanli acupoint was positively correlated to that in stomach (r = 0.963,P < 0.001).Conclusions When ARDS is under the condition of systemic oxygen delivery disorder, the demand of organ tissues for oxygen is significantly increased, but the oxygen utilization is impaired obviously, which is possibly related to the cellular mitochondrial dysfunction. There is good correlation between the tissue oxygen partial pressure of acupoint tissue and related organ tissue. The detection of oxygen in acupoint tissue has important guidance significance for monitoring the oxygen metabolism of related organ tissues.