摘要
目的探讨肺泡复张后不同通气模式和自主呼吸在防止肺泡再萎陷中的作用。方法选择健康杂种犬18只,建立油酸所致急性呼吸窘迫综合征(ARDS)模型,行容积控制通气(VCV),呼气末正压(PEEP)16cm H_2O,潮气量(V_T)10ml/kg,通气频率30次/min,稳定后作为基础状态。以压力控制通气(PCV,PEEP 35cm H_2O,PCV 15cm H_2O,持续60s)行肺泡复张(RM),分为3组:VCV 组(VCV 通气,V_Υ 15ml/kg),PCV 组(PCV 通气,调节压力控制水平使 VT 保持在15ml/kg)和 SB 组(PCV 通气,保留一定程度的自主呼吸,调节压力控制水平使 V_Υ保持在15ml/kg)。3组通气频率(20次/min)、PEEP(10cm H_2O)和吸/呼比(1:2)均相同。观察4h 后处死动物。结果 VCV 组、PCV 组及 SB 组低位拐点分别为(16.1±1.9)cm H_2O,(17.4±1.5)cm H_2O 和(17.1±1.6)cm H_2O。在使用肺泡复张后,VCV 组 PaO_2维持在与基础状态相近的水平,而 PCV 组和 SB 组 PaO_2显著高于基础状态。与 VCV 组相比,SB 组 PaO_2在第30min 明显增高(P<0.05),肺内分流在第5、30与60min 有明显降低趋势(P 值分别为0.077、0.058、0.076)。(3)与基础状态相比,肺泡复张后各组平台压及平均气道压均明显降低,其中 SB 组平台压明显低于 VCV 组(P<0.05),平均气道压从第120min 直至实验结束均明显低于其他两组(P<0.05)。结论在肺泡复张后选用 PCV 并保留一定程度的自主呼吸,能弥补较低 PEEP 在防止肺泡再萎陷方面的不足,较 VCV 更有效、安全。
Objective To investigate the role of different ventilatory modes and spontaneous breathing （SB） in prevention of derecruitment in acute respiratory distress syndrome （ARDS）. Methods Eighteen dog ARDS models were established by injection of oleic acid into the central vein and ventilated with volume controlled ventilation （VCV,） with the positive end expiratory pressure （PEEP） of 16 cm H2O, tidal volume （ VT ） of 10 ml/kg, and respiratory rate （RR） of 30 bpm, and the steady state in this mode was defined as baseline （0 min）. After the baseline state was reached, all dogs accepted recruitment maneuver （RM） in pressure controlled ventilation （PCV）mode at the level of 15 cm H2O and PEEP of 35 cm H2O for 1 rain, and then assigned into three groups and ventilated for 4 hs ： VCV group（ VCV with Vr of 15 ml/kg）, PCV group in which the peak inspiratory airway pressure was adjusted for keeping 15 ml/kg of VT, and SB grouping which PCV with SB activity and inspiratory airway pressure were adjusted for keeping 15 ml/kg of Vr. PEEP of 10 cm H2O, RR of 20 bpm, and inspiratory/expiratory ratio of 1/2 were kept for all animals. Four hours later the dogs were killed and their lungs were taken out. Results （ 1 ） The lower inflection points were identified as 16.1 ± 1.9, 17.4 ± 1.5, and 17.1 ± 1.6 cm H2O for the VCV, PCV, and SB group respectively. （2） After RM, the PaO2 levels of the PCV and SB groups were kept higher than baseline, but the PaO2 level was as same as that in the baseline state in the VCV group. Compared with the VCV group, higher PaO2 the PaO2 level 30 min after RM in the SB group was found （ P 〈 0.05 ）. The intrapulmonary shunt 5 min, 30 min and 1 hr after RM in the SB group were all lower than those in the VCP group, however, not significantly （P = 0. 077,0. 058,0. 076）. （3） Compared with baseline levels, the plateau pressure and mean airway pressure in all animals were decreased significantly after RM. The plateau pressure in the SB group was sig
出处
《中华医学杂志》
CAS
CSCD
北大核心
2007年第37期2635-2639,共5页
National Medical Journal of China
基金
北京市科技新星计划资助项目(2005 B03 )
北京市教育委员会科技发展计划资助项目(KM200510025007)
关键词
呼吸窘迫综合征
成人
肺通气
Respiratory distress syndrome, adult
Pulmonary ventilation
