犬股骨干骨折合并失血性休克髓内钉固定对肺功能的影响

The Influence of Intramedullary Nailing on Pulmonary Functions of Canine with Femoral Fracture and Hemorrhagic Shock: an Experimental Study

【目的】探讨犬股骨干骨折合并失血性休克复苏后不同内固定方法对肺功能的影响。【方法】18条健康杂种犬,股动、静脉插管,放血造成股骨干骨折合并失血性休克,复苏后8h分别用钢板(plate,P)、不扩髓钉(unreamedfemoralnailing,UFN)和扩髓钉(reamedfemoralnailing,RFN)内固定。在术前至术后8h内7个不同时间段动脉血气分析,计算肺泡-动脉血氧分压递差犤P(A-a)DO2,p(A-a,DO2)犦,氧合指数(PaO2/FiO2,pa,O2/FI02)和肺死腔分数(Vd/Vt)。【结果】P组,术中各项指标无明显改变;UFN组术后各项指标有改变,但术后2～4h内恢复正常;RFN组,p(A-a,DO2)升高,Vd/Vt增大,pa,O2/FI02降低,且呈持续状态,术后8h时和基础水平相比,差异仍具显著性。各项指标各时间段RFN组和另两组差异均具有统计学意义。【结论】股骨干骨折合并失血性休克,复苏后早期扩髓固定,和不扩髓及钢板固定相比,对肺功能产生更大影响。

To investigate the influence of difference fixation methods on pulmonary function in canine with femoral fracture complicating hemorrhagic shock.18 adult mixed breed dogs were used in this study. Catheters were inserted into left femoral artery and vein . Hemorrhagic shock was induced by withdrawal of blood from the arterial catheter. Eight hours after resuscitation, the dogs were divided into three groups randomly based on the different internal fixation methods: plate, unreamed intramedullary nailing and reamed intramedullary nailing. The arterial blood gas were analysed at seven different time points.The alveola arterial oxygen gradient[P(A a)DO2, p(A a,DO2)], oxygenation ratio(PaO2/FiO2,pa,O2 / FI02)and alveolar dead space fraction(Vd / Vt) were calculated .There were no changes of all indexes in the plate group. The unreamed nailing group had a moderate increase of p(A a,DO2 and Vd / Vt, and a decrease in pa,O2 / FI02.But they all returned to normal from 2 to 4 h after the fixation. However with the application of reamed nailing, p(A a,DO2 and Vd / Vt remained elevated and deceased pa,O2 / FI02 persisted within 8 h after the fixation. Compared with the other two groups, significant differens in p(A a,DO2, pa,O2 / FI02 and Vd /Vt at all time points were observed in the reamed nailing group.[Conclusion]After resuscitation of canine with femoral fracture and hemorrhagic shock, early fixation of fracture with reamed nailing will yield greater influence on the pulmonary function compared with plate and unreamed nailing.