俯卧位通气联合肺复张对ARDS氧合及肺复张容积的影响

Effects of prone position ventilation combined with recruitment maneuvers on oxygenation and lung recruited volume in canines with acute respiratory distress syndrome

目的:探讨俯卧位通气联合肺复张对急性呼吸窘迫综合征(ARDS)氧合及肺复张容积的影响。方法:健康杂种犬24只,油酸静脉注射复制ARDS模型,再随机分为4组,每组6只,分别应用仰卧位常规机械通气(SC组)、仰卧位联合控制性肺膨胀(SI)(SS组)、俯卧位通气(PC组)、俯卧位通气联合SI(PS组)。各组观察5h,记录氧合及肺复张容积等指标的变化。结果:①与SC组相比,SS组PaO2/FiO2仅在成模后2h显著增高(P<0.05),而PC组和PS组PaO2/FiO2在成模后2h及5h均高于SC组(P均<0.05)。成模2h及5h,PS组PaO2/FiO2明显高于SC组、PC组、SS组(P均<0.05);②成模0h,4组的肺复张容积差异无统计学意义(P均>0.05)。成模2h,SS组、PC组、PS组肺复张容积较SC组明显增加(P均<0.05)。成模5h,与SC组相比,SS组肺复张容积呈减少趋势,PC组、PS组肺复张容积呈增高趋势。结论:俯卧位通气联合SI较单应用俯卧位通气及单应用SI能更好的改善ARDS氧合,肺复张容积的显著增加可能是主要机制之一。

Objective：To evaluate the effects of prone position ventilation combined with recruitment maneuvers（RM） on oxygenation and lung recruited volume（RV） in oleic acid-induced acute respiratory distress syndrome in canines. Methods：Twenty-four healthy canines were randomly divided into four groups after oleic acid-induced lung injury：supine position group（SC）,supine position＋RM group（SS）,prone position group（PC） and prone position＋RM group（PS）. Oxygenation index and RV were measured for five hours after ARDS was reproduced. Results：（1）Compared to the SC group,oxygenation index in SS group was increased only at 2 h after onset of ARDS（P 〈 0.05）,while that of PC and PS group improved both at 2 h and 5 h after onset of ARDS（all P 〈 0.05）. Compared to the SC,SS,and PC group,PS group oxygenation index was much higher at 2 h and 5 h after onset of ARDS（all P 〈 0.05）. （2）There was no significant difference of RV among the four group at 0 h after onset of ARDS（all P 〉 0.05）. Compared to the SC group,RV in SS,PC and PS group was much higher at 2 h after onset of ARDS（all P 〈 0.05）. At 5 h after onset of ARDS,the RV of the SS group had a tendency to decrease while the RV of the PC and PS group had a tendency to increase. Conclusion：Prone position ventilation combined with RM improved oxygenation significantly. The increase of RV may be one of the most important mechanisms of its positire effect.