止血带与全膝关节置换术肺脂肪栓塞风险的实验研究

Effect of tourniquet on pulmonary fat embolisms during total knee arthroplasty:an experimental study

目的探讨止血带对全膝关节置换术(TKA)肺脂肪栓塞产生的影响。方法 16只杂种犬随机分为两组。实验组:模拟TKA截骨、扩髓,插入髓内杆,术中使用止血带;对照组:术中操作同实验组,术中不使用止血带。术中监测不同时间动脉血气分析、凝血指标和血管内皮损伤指标,术后进行肺脏病理检查并采用病理学评分计算肺损伤程度。结果血气分析监测发现在释放止血带后5min内实验组氧分压下降值高于对照组(P<0·05)。凝血酶原时间和活化部分凝血活酶时间两组间的差异无统计学意义。术后实验组组织型纤溶酶原激活物低于对照组(P<0·05),血管性血友病因子和血栓调节蛋白均高于对照组(P<0·05)。肺损伤总分实验组高于对照组(5·6±2·3)vs(3·2±1·4),(P<0·05)。结论 TKA术中使用止血带可能损伤血管内皮,止血带释放时可能干扰呼吸系统功能,增加肺脏脂肪栓塞的发生风险。

Objective To determine the effects of tourniquet on pulmonary fat embolisms during total knee arthroplasty. Methods 16 dogs were randomized into two groups： tourniquet group was simulated total knee arthroplasty with a tourniquet （ n = 8 ）, while non-tourniquet group was operated without tourniquet （ n =8 ）. Arterial blood gas analysis, index of blood coagulation and blood vessel endothelium function were tested at different time points during the operation. HE-staining for lungs was taken to detect the degree of pulmonary injury. Results Five minutes after the tourniquet was released in the tourniquet group, PaO2 significantly decreased much more than it in the non-tourniquet group （ P 〈 0. 05）. There was no significant difference in prothrombin time and activated partial thromboplastin time between the two groups. The level of tissue plasminogen activator in the tourniquet group was lower while the level of yon Willebrand factor and thrombomodufin were hegher in the tourniquet group than in the non- tourniquet group （ P 〈 0. 05 ）. Pulmonary injury score was higher in the tourniquet group than in the non- tourniquet group （5.6± 2. 3 vs 3.2 ± 1.4,P 〈 0. 05 ）. Conclusions Tourniquet in total knee arthroplasty may damage blood vessel endothelium; furthermore, tourniquet release may interfere respiratory system, and may increase the risk of pulmonary fat embolism during TKA.