肺复张对肺内/外源性急性呼吸窘迫综合征模型犬呼吸生理和肺形态学影响的比较  

Comparative study of recruitment maneuver guided by pressure-volume curve on respiratory physiology and lung morphology between acute respiratory distress syndrome of pulmonary and extrapulmonary origin in canine models

作　　者：熊旭明[1] 温德良[1] 温艺超[1] 刘卫江[1] 

机构地区：[1]广州医学院第二附属医院危重病学科,广东510260

出　　处：《中国危重病急救医学》2011年第1期36-39,共4页Chinese Critical Care Medicine

基　　金：基金项目：广东省科技计划项目（20078060401067）

摘　　要：目的 探讨以压力-容积（P-V）曲线为导向的肺复张（RM）策略对肺内/外源性急性呼吸窘迫综合征（ARDSexp/ARDSp）模型犬呼吸生理和肺形态学的影响.方法 将24只健康杂种犬按随机数字表法均分为两组,分别以静脉注射油酸0.1 ml/kg复制ARDSexp模型,以气管内注入盐酸2 ml/kg复制ARDSp模型.每种模型再随机均分为肺保护通气策略（LPVS）组和LPVS＋RM组.LPVS组采用LPVS进行机械通气（MV）;LPVS＋RM组先进行以P-V曲线为导向的RM,RM采用压力控制通气（PCV）,压力上限为高位转折点（UIP）,呼气末正压（PEEP）为低位转折点（LLP）＋2 cm H2O（1 cm H2O=0.098 kPa）,维持60 s后再按LPVS进行MV.两组MV时间均为4 h.观察动物基础状态（成模前）及RM前后的氧合指数（PaO2/FiO2）、呼吸力学指标变化;采用低流速法记录准静态P-V曲线并计算UIP、LIP ;根据肺CT比较不同肺充气区容积占全肺容积的百分比.结果 成模前和RM前两组PaO2/FiO2及UIP、LIP比较差异均无统计学意义.RM后4 h,两种模型LPVS＋RM组PaO2/FiO2和肺顺应性（Crs）均较同模型LPVS组显著升高[ARDSexp模型PaO,/FiO2（mm Hg,1 mm Hg=0.133 kPa）：263.9±69.2比182.8±42.8,Crs（ml/cm H2O）：11.3±4.2比9.7±3.7;ARDSp模型PaO2/FiO2（mm Hg）：193.4±33.5比176.4±40.2,Crs（ml/cm H2O）：10.1±3.9比9.0±3.9,P＜0.05或P＜0.01],气道压力明显低于同模型LPVS组[ARDSexp模型吸气峰压（PIP,cm H2O）：24.1±7.4比30.2±8.5,气道平台压（Pplat,cm H2O）：19.1±7.3比25.6±7.7;ARDSp模型PIP（cm H2O）：26.6±8.4比29.6±10.3,Pplat（cm H2O）：21.9±7.3比25.1±8.4,P＜0.05或P＜0.01];且ARDSexp模型改善程度较ARDSp模型更为显著（P＜0.05或P＜0.01）.两种模型LPVS＋RM组肺组织闭合区和充气不足区所占比例均较同模型LPVS组明显减少,正常充气区所占比例明显增加[ARDSexp模型闭合区：（9.9±3.1）%比（16.3±5.2）%,充气不足区：（10.2±4.2）%比（23.4±6.7）%,正Objective To determine effects of recruitment maneuver （RM） guided by pressure-volume （P-V） curve on respiratory physiology and lung morphology in canine models of acute respiratory distress syndrome of pulmonary or extrapulmonary origin （ARDSp and ARDSexp）. Methods Twenty-four healthy dogs were randomly divided into two groups with 12 dogs each： ARDSexp and ARDSp. Each dog in ARDSexp group was injected with oleic acid 0. 1 ml/kg through femoral vein, and each dog in ARDSp group received hydrochloric acid 2 ml/kg via trachea. Subsequently, dogs with both models were randomly subdivided into lung protective ventilation strategy （LPVS） group and LPVS＋RM group, respectively. Dogs in LPVS group were given LPVS only without RM. RM guided by P-V curve was performed in LPVS＋RM group followed by LPVS and pressure controlled ventilation （PCV） mode was selected. Phigh was set at upper inflection point （UIP） of the P-V curve, positive end-expiratory pressure （PEEP） was set at lower inflection point （LIP）＋2 cm H2O （1 cm H2O=0. 098 kPa）, and the duration of RM was 60 seconds. The duration of mechanical ventilation （MV） in both subgroups was 4 hours. The oxygenation index （PaO2/FiO2）, relative lung mechanical indexes were measured in two ARDS models before establishment of ARDS model, and before and after RM. The UIP and LIP were calculated with P-V curve. The percentage of different volume in ventilation of lung accounting for total lung volume was compared by CT scan.Results The PaO2/FiO2, UIP and LIP did not showed significant differences among all groups before ARDSand before RM. PaO2/FiO2 and respiratory system compliance （Crs） were significantly elevated in LPVS＋RM group of both models 4 hours after RM compared with corresponding LPVS group [PaO2/FiO2（mm Hg,1 mm Hg=0. 133 kPa） of ARDSexp model： 263. 9±69. 2 vs. 182.8±42. 8, Crs （ml/cm H2O） of ARDSexp model： 11.3±4. 2 vs. 9. 7±3. 7; PaO2/FiO2（mm Hg） of ARDSp model： 193. 4±33.5 vs. 176. 4±40.

关 键 词：急性呼吸窘迫综合征 肺复张 肺保护通气策略 压力-容积曲线 

分 类 号：R563.8[医药卫生—呼吸系统]