Difference in influences of between reamed and unreamed intramedullary femoral nailing on lung function

目的：髓内钉术后肺部并发症已成为许多外科医生关注的焦点。我们研究了正常肺状态下绵羊经股骨髓内钉扩孔或未扩孔后肺功能和凝血反应是否发生改变。实验分为三组，每组n=5只羊：扩孔股钉组（RFN）、未扩孔股钉组（UFN）和假手术对照组（SOC）。所有实验包括血流动力学监测、血气分析和生化采样（ATIII、LPO、甘油三酯、纤维蛋白原）。钉入6小时后分析各组动物支气管肺泡灌洗液（BALF）。肺组织髓过氧化物酶（MPO）活性测定。结果：三组患者肺血管阻力、全身血管阻力、AaDO2等血流动力学监测数据及生化数据的时间进程均无显著差异。BALF分析中，RFN和UFN组白细胞计数高于SOC组，RFN组脂质细胞含量高于UFN和SOC组。与其他两组相比，RFN组肺组织中MPO活性最高。结论：在生理水平上，RFN对肺功能无影响，在急性期不引起高凝反应。然而，根据BALF结果和MPO检测结果，在亚临床水平上，RFN可能对肺有害。

Objective: Pulmonary complicate after intramedullary nailing have been focused by many surgeons. We investigated whether the pulmonary function and the coagulatory response after reamed or unreamed intramedullary femoral nailing in normal lung status of sheep is altered Materials and Methods: A total of 15 adult sheeps were used. This experiment involved three groups (each, n=5) of sheep: reamed femoral nailing (RFN) groups, unreamed femoral nailing (UFN) group, and sham operation control (SOC) group. All experiments involved hemodynamic monitoring, blood gas analysis, and biochemical sampling (ATIII, LPO, triglyceride, fiblinogen during and 0 to 6 hours after the nailing. Bronchoalveolar lavage fluid (BALF) in each animal was analyzed 6 hours after nailing. Myeloperoxidase (MPO) activity in the pulmonary tissue was also examined after BAL. Results: There were no significant differences in both the time courses of hemodynamic monitoring data including pulmonary vascular resistance, systemic vascular resistance, and AaDO2, and those of biochemical data among three groups. In BALF analysis the leukocyte cell counts of RFN and UFN groups were higher than that of SOC group, and the lipid-laden cells of RFN group was higher than those of UFN and SOC groups. The MPO activity in puImonary tissue of RFN group was the highest, compared to those of the other two groups. Conclusion: RFN m normal lung status does not influence on pulmonary function in physiological level, and does not induce hyper-coagulatory response, at acute stage. However, RFN could be detrimental to lung in subclinical level on the basis of both the BALF results and the MPO assay results.