不同吸气流速下机械通气对ARDS患者气道平台压的影响研究

Effects of mechanical ventilation at different inspiratory flow rates on airway plateau pressure in ARDS patients

目的探讨不同吸气流速下机械通气对ARDS患者气道平台压的影响研究。方法选取60例已机械通气的ARDS患者,按随机表法分为3组进行机械通气治疗。均采用6~8 m L/kg小潮气量通气及允许高碳酸血症策略。均采用容量控制ACV模式,流速波形均选用恒速波。3组采用不同吸气峰值流速(A组40 L/min、B组60 L/min、C组80 L/min)。测定并记录通气时的气道峰压(Ppeak),气道平均压(Pmean),气道平台压(Pplat),动态顺应性(Cdyn),并记录治疗后的第1个24 h人机对抗的发生例数、机械通气的时间及停留于重症监护室的时间,比较两组患者呼吸力学、血气分析及血流动力学各指标的变化。结果 B组和C组在调整吸气流速之后的Ppeak,Pplat,Cdyn有明显上升(P<0.05)。C组在调整吸气流速之后同时段比较Ppeak和Pplat,Cdyn明显高于A组(P<0.05),Pmean稍高A组,但差异无统计学意义,C组Ppeak和Pplat,Cdyn,明显高于B组(P<0.05)。在人机对抗的对比分析中:C组与A组及B组相比,例数明显增加(P<0.05)。且B组多于A组(P<0.05)。在机械通气时间与停留ICU时间的对比分析中,C组较A组和B组,显著延长(P<0.05)。3组在通气2 h,4 h及第1个24 h监测患者血气分析及血流动力学无明显变化,差异无统计学意义。结论在小潮气量基础上,降低吸气流速,对损伤的肺组织可起到一定的保护作用,更利于维持机协调。

Objective To study the effect of mechanical ventilation on airway pressure in ARDS patients under different inspiratory flow rates.Methods Sixty patients with ARDS who had been mechanically ventilated were divided into three groups according to the randomized table methodfor mechanical ventilation.Were used6-8mL/kg low tidal volume ventilation and allow hypercapnia strategy.Are used to control the ACV mode capacity,flow velocity waveforms are selected constant speed wave.3groups were treated with different inspiratory peak flow rate(group A40L/min,group B60L/min,group C80L/min).(Ppeak),airway mean pressure(Pmean),airway plateau pressure(Pplat),dynamic compliance(Cdyn)were recordedand recorded,and the first24hours after treatment were recorded.The number of cases,the time of mechanical ventilation and the time ofstay in the intensive care unit were compared.The changes of respiratory mechanics,blood gas analysis and hemodynamics were compared betweenthe two groups.Results Ppeak,Pplat and Cdyn were significantly increased in group B and group C(P<0.05)after adjusting the inspiratory flowrate.Compared with group A(P<0.05),Ppak and Pplat were significantly higher than those in group A(P<0.05),but the difference was not statisticallysignificant.The Ppeak,Pplat and Cdyn in group C were significantly higher than those in group B(P<0.05).In the comparative analysis ofman-machine confrontation:the C group compared with the A group and the B group,the number of cases increased significantly(P<0.05).The Bgroup was more than the A group(P<0.05).In the comparative analysis of the mechanical ventilation time and the ICU time,the C group was significantlylonger than the A group and the B group(P<0.05).There was no significant difference in blood gas analysis and hemodynamics between thetwo groups at2h,4h and1h24h.Conclusion On the basis of the small tidal volume,the inspiratory flow rate is reduced,and the protective lung tissuecan play a protective role,which is more conducive to the maintenance of machine coordination.