Sivrikoz M Cumhur, Tunçözgür Bülent, Cekmen Mustafa, Bakir Kemal, Meram Iclal, Koçer Emrah, Cengiz Beyhan, Elbeyli Levent
Department of Thoracic and Cardiovascular Surgery, Gaziantep University School of Medicine, 27070 Kolejtepe, Gaziantep, Turkey.
Eur J Cardiothorac Surg. 2002 Nov;22(5):721-7. doi: 10.1016/s1010-7940(02)00447-5.
The aim was to discuss the balance between free radical damage and body defense mechanisms that occurred in reexpansed pulmonary tissue and to evaluate the relationship between the changes in the pulmonary circulation and the mentioned balance.
Twenty male Wistar Albino rats were used for these study results. Pneumothorax was created in the left hemithorax by percutaneous route in all the rats. After 7 days, the first group (n = 10) had a sternotomy under ketamine anesthesia. Following invasive measurement of pulmonary artery pressure, tissue samples were obtained from the lower lobes of the right and left lungs before reexpansion occurred. Tracheotomies were opened in the second group (n = 10) with a 16 gauge cannula. Following sternotomy, invasive mean pulmonary artery pressure measurements were obtained by the support of non-invasive cardiac monitorization. The lungs were aerated with 4 cmH(2)O oxygen and fixed volume support and 1 h of reexpansion was obtained. Invasive mean pulmonary artery pressure measurements were repeated after reexpansion and tissue samples were obtained from the lower lobes of left and right lungs. Nitric oxide (NO), malondialdehyde (MDA) and superoxide dismutase (SOD) levels were measured in tissue samples, surfactant staining and light microscopic evaluations were performed.
At the end of the reexpansion, there was a decrease in mean pulmonary artery pressure (P < 0.01), MDA (P < 0.01) and SOD (P < 0.05) levels and an increase in NO (P < 0.05) levels. Under the light microscopic examination, in the samples that were provided with reexpansion, the alveolo-capillary membrane was thickened due to increasing edema, increase in the number of lymphocytes and return of the neutrophil leukocytes to the area. There was no significant difference between the groups in terms of surfactant staining.
The tissue reperfusion that is achieved with the restoration of blood flow during the reexpansion of collapsed lungs, can be the initial pathology in the chain of events that result in reexpansion injury.
探讨复张肺组织中自由基损伤与机体防御机制之间的平衡，并评估肺循环变化与上述平衡之间的关系。
采用20只雄性Wistar白化大鼠进行本研究。所有大鼠均经皮途径在左半胸制造气胸。7天后，第一组（n = 10）在氯胺酮麻醉下行胸骨切开术。在有创测量肺动脉压后，在肺复张前从左右肺下叶获取组织样本。第二组（n = 10）用16号套管进行气管切开术。胸骨切开术后，在无创心脏监测支持下进行有创平均肺动脉压测量。用4 cmH₂O氧气和固定容量支持使肺通气，实现1小时的复张。复张后重复有创平均肺动脉压测量，并从左右肺下叶获取组织样本。测量组织样本中的一氧化氮（NO）、丙二醛（MDA）和超氧化物歧化酶（SOD）水平，进行表面活性剂染色和光镜评估。
复张结束时，平均肺动脉压（P < 0.01）、MDA（P < 0.01）和SOD（P < 0.05）水平降低，NO（P < 0.05）水平升高。光镜检查显示，在复张的样本中，由于水肿增加、淋巴细胞数量增加和中性粒细胞返回该区域，肺泡 - 毛细血管膜增厚。两组在表面活性剂染色方面无显著差异。
萎陷肺复张过程中血流恢复所实现的组织再灌注，可能是导致复张性损伤的一系列事件中的初始病理变化。
