无心跳兔呼出气中异戊二烯浓度变化

目的观察兔心跳停止后不同时间呼出气中异戊二烯浓度变化。方法无心跳兔随机分为A-E组(n=8),分别为心跳停止后0 min、30 min、60 min、90 min和120 min。使用气相色谱-质谱仪测量呼出气中异戊二烯浓度;传统肺损伤检测方法包括:肺脏组织湿干重(W/D)比、丙二醛(MDA)浓度、肺损伤评分(LIS)和气道压30 cm H2O时肺容积(Vmax)。结果 A-E组呼出气中异戊二烯浓度[中位数(四分位区间)]分别为1.39(3.70-0.68)ppb、0.94(2.02-0.32)ppb、1.00(1.73-0.48)ppb、0.95(0.99-0.86)ppb和0.39(1.45-0.34)ppb,E组显著低于A组(P<0.05)。传统肺脏损伤检测指标随时间进行性加重,E组损伤最重。结论呼出气中异戊二烯浓度在心跳停止120 min内随肺损伤加重呈渐进性下降。

Change of isoprene in expiratory air of rabbits without heartbeat

Objective To detect the concentrations of isoprene in expiratory air during different periods of rabbits without heart- beat （CA）. Methods 40 rabbits were randomly and evenly divided into5 groups at0 min, 30 min, 60 min, 90 min, and 120 min after cardiac arrest respectively. The concentrations of isoprene were collected by gas chromatography-mass spectrometer. The traditional detec- tion methods of lung injury included wet-to-dry （W/D） ratio, malonaldehyde （MDA） concentrations, lung injury scores （LIS） and maxi- mal volume of lung when the airway pressure reached 30 cmH2O （ Vmax）. Results From the group A to E, the median concentrations of isoprene were 1.39 （3.70 - 0.68） ppb, 0.94 （ 2.02 - 0.32 ） ppb, 1.00 （ 1.73 - 0.48 ） pph, 0.95 （0.99 - 0.86 ） ppb and 0.39 （ 1.45 -0. 34） ppb respectively, and the isoprene concentration was significantly lower in the group E than in the group A （P 〈 0. 05 ）. The indexes of traditional lung injury aggravated with time and the group E was the most severe group. Conclusion The concentration of exhaled isoprene decreases with the severity of lung injury within 120 min after CA.