Cakir Omer, Oruc Ahmet, Eren Sevval, Buyukbayram Huseyin, Erdinc Levent, Eren Nesimi
Department of Thoracic and Cardiovascular Surgery, Dicle University, School of Medicine, Diyarbakir, Turkey.
Eur J Cardiothorac Surg. 2003 Jun;23(6):1040-5. doi: 10.1016/s1010-7940(03)00166-0.
We hypothesized that direct pulmonary arterial infusion of sodium nitroprusside (SNP) would ameliorate lung injury under cardiopulmonary bypass.
Experiments were performed on 12 adult mongrel dogs of both sexes weighing 20-28 kg. The animals were randomly divided into two groups of six animals each. All animals were subjected to total cardiopulmonary bypass (CPB) and moderate hypothermia (28 degrees C core temperature). During total CPB, the aorta was clamped together with the pulmonary artery to prevent any antegrade flow to the lungs. After cardioplegic arrest for 120 min, the animals were rewarmed, weaned from CPB, and their condition stabilized for another 90 min. After the release of the aortic cross-clamp, the dogs received either a 5% glucose solution as a placebo (group I) or SNP (0.5 microg/kg per min) (group II), both infused into the pulmonary arterial line. The infusion was stopped after 60 min. To measure lung tissue malondialdehyde (MDA), water content and polymorphonuclear leukocytes count, lung tissue samples were taken before CPB and after weaning from CPB. In addition, alveolar-arterial oxygen difference (AaDO(2)) for tissue oxygenation was calculated by obtaining arterial blood gas samples.
Values of MDA before CPB of 42.0+/-5.3 nmol/g of tissue rose to 67.6+/-5.7 nmol/g of tissue after weaning from CPB in group I (P=0.028). In group II MDA values also increased from 43.1+/-4.3 to 52.4+/-5.7 nmol MDA/g of tissue after weaning from CPB (P=0.046). The MDA increase in group II after CPB was found to be significantly lower than that for group I (P=0.004). The wet-to-dry lung weight ratio in the sodium nitroprusside group was 5.1+/-0.2, significantly lower than in the control group (6.8+/-0.4), (P=0.01). AaDO(2) increased significantly in group I (P=0.028). There was no statistically significant difference (P=0.065) between groups I and II. During histopathological examination it was observed that neutrophil counts in the lung parenchyma rose significantly after CPB in both groups. The increase in group I was significantly larger than that in group II (P<0.001).
The results represented in our study indicate that pulmonary arterial infusion of sodium nitroprusside during reperfusion can reduce lung injury under cardiopulmonary bypass.
我们推测直接肺动脉输注硝普钠（SNP）可改善体外循环下的肺损伤。
对12只体重20 - 28 kg的成年杂种犬进行实验，雌雄不限。动物被随机分为两组，每组6只。所有动物均接受全身体外循环（CPB）及中度低温（核心体温28℃）。在全身体外循环期间，主动脉与肺动脉一起被阻断，以防止任何血液顺行流入肺部。心脏停搏120分钟后，动物复温，脱离体外循环，并使其状况稳定90分钟。松开主动脉阻断钳后，犬只接受5%葡萄糖溶液作为安慰剂（I组）或SNP（0.5微克/千克每分钟）（II组），两者均经肺动脉导管输注。60分钟后停止输注。为测量肺组织丙二醛（MDA）、含水量及多形核白细胞计数，在体外循环前及脱离体外循环后采集肺组织样本。此外，通过采集动脉血气样本计算组织氧合的肺泡 - 动脉氧分压差（AaDO₂）。
I组体外循环前肺组织MDA值为42.0±5.3纳摩尔/克组织，脱离体外循环后升至67.6±5.7纳摩尔/克组织（P = 0.028）。II组MDA值在脱离体外循环后也从43.1±4.3升至52.4±5.7纳摩尔MDA/克组织（P = 0.046）。发现II组体外循环后MDA的增加显著低于I组（P = 0.004）。硝普钠组肺湿重与干重之比为5.1±0.2，显著低于对照组（6.8±0.4），（P = 0.01）。I组AaDO₂显著增加（P = 0.028）。I组和II组之间无统计学显著差异（P = 0.065）。在组织病理学检查中观察到，两组体外循环后肺实质中的中性粒细胞计数均显著升高。I组的升高显著大于II组（P < 0.
