体视学定量法评估氧控制性再灌注对犬体外循环肺缺血再灌注早期损伤的保护作用

摘要

This paper is purposed to evaluate the protective effects of oxygen controlled reperfusion on lung in early stage of ischemia reperfusion with cardiopulmonary bypass (CPB) by stereological study. 14 canines were randomized into two groups: group IR ( ischemic reperfusion, n = 7 ) and group OCR ( oxygen controlled reperfusion, n = 7 ). All animals received CPB as clinical practice. In group IR, the animals received 80 % of the FiO2; In group OCR, the animals received 40 % ,50 % ,60 % ,70 % and 80 % of the FiO2 with CPB immediately after declamping sequentially, each oxygen concentration lasted for 5 minutes, other procedures were the same as group IR. Lung tissue were collected at Tl (just after sternotomy) , T2 (25 min after aortic declamping ) and T3 (90 min after aortic declamping ) for HE staining. Ten visual fields from each section were selected. Polymorphonuclear neutrophil count (PMN ) , the area and density of pulmonary alveolar septum ( PASAD) , the volume density of alveolus in the lung and the volume density of the erythrocyte in the lung were analyzed with the Image-Pro image analysis system. Wet/Dry/D weight (W/D) was analyzed. There were no significance in all parameters at T1 between the two groups. With the time prolonged, the PMN, the PASAD and volume density of the erythrocyte in the lung in two groups kept increasing, especially in IR group ( P < 0. 05 ) ; The volume density of the alveolus in two groups kept decreasing, especially in IR group (P < 0. 05 ). Compared with that in IR group, W/D ratio decreased significantly at T2 and T3 (P < 0. 05 ) in OCR group. Oxygen controlled reperfusion is protective in lung I/R during CPB.%利用体视学定量法,评估氧控制性再灌注对体外循环肺缺血再灌注早期损伤的保护作用.14只健康犬随机分为缺血再灌注组( IR,n＝7)和氧控制性再灌注组(OCR,n＝7).IR组全程FiO2 80％；OCR组在主动脉开放即刻调整FiO2至40％,随后每5 min依次上调10％,最后达80％,其余时段均维持FiO2 80％.在开胸后即刻(T1)、主动脉开放25 min(T2)、主动脉开放90 min(T3),留取肺组织标本进行HE染色.每张切片随机取10个视野,用Image - Pro图像分析软件,分别测试肺泡间隔中性粒细胞(PMN)计数、肺泡间隔面积密度(PASAD)、肺泡腔体积密度和肺实质红细胞体积密度,检测肺组织湿干重比(W/D).两组肺组织各参数在TI差异无显著性(P＞0.05),OCR组肺泡间隔中性粒细胞计数、肺泡间隔面积密度和红细胞体积密度在T2和T3时点较IR组降低(P＜0.05),OCR组肺泡腔体积密度在T2和T3时点较IR组明显增大(P＜0.05).OCR组肺组织湿干重比(W/D)在T2和T3时点较IR组明显降低(P＜0.05).采用体视学定量法,提示氧控制性再灌注对体外循环肺缺血再灌注早期损伤具有保护作用.