肺泡复张手法对急性肺损伤氧合的影响

Effects of recruitment maneuver on oxygenation in rabbits with acute lung injury

目的 对比研究肺泡复张手法 (RM)分别应用于高频震荡通气 (HFOV)和常规机械通气(CMV)对急性肺损伤 (ALI)氧合的影响。方法 采用肺泡灌洗法建立ALI大耳白兔模型 ,分别行HFOV和CMV通气 ,RM实施压力为 30cmH2 O ,持续 30s。对RM前、期间 (急性肺损伤基础状态 )、RM后 5、 15、30min和 1h时的动脉血气、血压及心率进行监测。结果 应用RM后HFOV组与CMV组的动脉氧分压(PaO2 )显著升高 (P <0 0 1)应用RM后 5minPaO2 升高最为明显 ,分别为 (2 6 3 3± 2 1 4 )mmHg (1mmHg=0 133kPa)和 (2 0 1 9± 5 9 8)mmHg。HFOV组PaO2 始终维持在这一水平 ,而CMV组PaO2 逐渐降低 ,RM后 1h [(12 3 5± 4 7 5 )mmHg]与 5min [(2 0 1 9± 5 9 8)mmHg]差异有显著意义 (P <0 0 5 )。在RM 15min后各时相HFOV组PaO2 显著高于CMV组 (P <0 0 5 )。二氧化碳分压、血压及心率在两组间差异无显著意义。结论 在HFOV和CMV中应用RM均可以有效地复张肺泡 ,改善氧合 ,但RM的复张作用在HFOV较CMV持续更长。

Objective To study the effects of RM on oxygenation in high frequency oscillatory ventilation (HFOV)and conventional mechanical ventilation(CMV).Methods Saline lavage induced acute lung injury rabbit models were randomly assigned to receive HFOV and CMV.Gas exchange and hemodynamics status were monitored before(damage status),at 5,15,30min and 1hour after RM.Results After RM,PaO 2 in HFOV group and CMV group increased( P <0 01),but higher in HFOV group.PaO 2 was the highest at 5min after RM(263 3±21 4,respectively) mm Hg and(201 9±59 8)mm Hg and kept relatively stable in HFOV group,but decreased gradually.PaO 2 was significantly lower at 1h(123 5±47 5)mm Hg than at 5 min(201 9±59 8)mm Hg after RM in CMV group( P <0 05).PaO 2 in HFOV group and CMV group were significantly different after RM 15min( P <0 05).PaCO 2,HR and MAP remained unchanged in two groups.Conclusion RM can recruit the collapsed alveoli in ALI and significantly improve oxygenation with the use of HFOV or CMV.Effects of RM combined with HFOV last longer than with CMV.Alveolar reexpansion may be essential to prevent lung injury. [