自主呼吸麻醉下家兔单肺呼吸模型的建立

Building one-lung respiration model in rabbits under spontaneous respiration anesthesia

目的探讨建立自主呼吸麻醉下兔单肺呼吸实验模型的方法。方法健康雄性新西兰大白兔共10只,将戊巴比妥配成1%的溶液,按3 m L/kg(30 mg/kg)于兔耳缘静脉缓慢注射进行诱导麻醉。予以自制面罩辅助给氧(氧流量4 m L/h)。右侧卧位后经左第6肋间开一大小约1 cm×1 cm切口观察肺萎陷情况,以左肺通气膨胀到萎陷为单肺呼吸模型建立成功。单肺呼吸2 h后,缝合胸壁后通过注射器抽取胸腔内气体实施肺复张。分别于单肺呼吸前(T0)、单肺呼吸30 min(T1)、单肺呼吸2 h(T2)和恢复双肺呼吸30 min(T3)4个时间点记录兔的心率、动脉压和动脉血气分析结果。结果实验中兔的血流动力学稳定,各时间点心率、平均动脉血压比较,差异均无统计学意义(P>0.05)。与T0时点比较,T2时点的p H显著降低(P<0.05),其余时点间p H差异均无统计学意义(P>0.05)。各时点间动脉血二氧化碳分压差异均无统计学意义(P>0.05)。与T0时点比较,T1和T2时点的动脉氧分压均显著降低(P<0.05);与T1时点比较,T3时点的动脉氧分压显著升高(P<0.05);与T2时点比较,T3时点的动脉氧分压显著升高(P<0.05)。自主呼吸状态下麻醉效果良好,而且操作方便,各时点动脉血气变化规律与临床一致。结论通过自制吸氧面罩可以建立新西兰大白兔自主呼吸麻醉下单肺呼吸模型。此模型简单方便,费用低,成功率高,适用于研究自主呼吸麻醉下相关的肺和远隔器官损伤病理生理机制。

Objective To build an experimental model of one-lung respiration model in rabbits under spontaneous respiration anesthesia. Methods Ten healthy New Zealand white rabbits were anesthetized with 1% sodium pentobarbital 3 mL/kg （30 mg/kg） intravenously administered through the ear vein. A homemade oxygen mask was cover the nose and mouth with 4 mL/h oxygen was used during the study. After the rabbits were fixed to right lateral position, the sixth of left intercostal space was opened a small incision （1cm×cm） to observe the lung collapse. The spontaneous respiration model was successfully established according to the left lung from expansion to collapse. Heart rate, mean arterial pressure and arterial blood gases were recorded in four phases： before thoracic surgery （T0）, 30 min after operation （T1）, 2 hours after operation （T2） and 30 minutes after returning to two-lung spontaneous respiration （T3）. Results The hemodynamic was stable in the experiment. Effective of rabbit model under spontaneous respiration anesthesia was satisfactory, safety and convenient. HR and MAP at different time point had no significant difference （P 〉 0.05）. Further analysis of blood gas, the results showed that the comparison of To, pH at T2 was significant lower （P 〈 0.05）, the other observations of pH at different time point had no statistical difference （P 〉 0.05）, PaCO2 of each group had no difference at different time point （P 〉 0.05）. Compared with To, PaO2 was significantly lower than that at T1 and T2 （P 〈 0.05）. Compared with T1, PaO2 was significantly higher than that at T3 （P 〈 0.05）. Compared with T2, PaO2 was significantly higher than that at T3 （P 〈 0.05）; the changes of arterial blood in each phase gases were similar to clinical. Conclusion The rabbit model of spontaneous respiration is easy to perform with self-made oxygen mask and can reduce the spending of animals and equipments. This model is suitable for the investigation of the pathophysiological mechanism in lung and remote organ injury induced by spontaneous respiration anesthesia.