摘要:
Objective To study the changes of trans-diaphragmatic pressure (Ptra) and its correlation with esophageal pressure (Peso) through ARDS piglet model.Methods Five piglets were enrolled in the study.Peso,gastric pressure (Pgas) and intra-thoracic pressure (Pint) was monitored through balloon inserted.The data before ARDS serve as control.ARDS was produced in the piglets through saline lavage.The pressure were observed and the Ptra were calculated.The pressure changes and correlation between Ptra and Peso were analyzed as well.Linear regression with the coefficient of determination and t-test were used as appropriate.Significance was assumed for P < 0.05.Results Peso,Pgas and Pint before ARDS were 7.3 ± 1.9,25.5 ± 2.4,- 1.23 ± 0.21 cmH2O,Ptra was 18.2 ± 1.6 cmH2O.While after ARDS,the data were 4.7 ± 1.4,31.1 ± 3.1 and - 1.79 ± 0.28 cmH2O,and Ptra was 26.4 ± 2.1 cmH2 O,and all these changes were obviously ( P < 0.05 ).The correlation between Pint and Peso,Pint and Ptra (A) and Ptra ( B ) were 0.93 ± 0.025,0.88 ± 0.023 and 0.87 ± 0.37 before ARDS.After ARDS,the correlation changed to be 0.82 ±0.21,0.81 ±0.20 and 0.78 ±0.31.Although a bit decreased,the correlation was still positive (P < 0.01 ).Conclusions There existed good correlations between Peso and Ptra as well as between Pint and Peso before or after ARDS.Ptra was increased obviously after ARDS,which could lead to respiratory muscle fatigue.%目的 拟通过建市家猪ARDS动物模型,测定胸内压、食管压以及胃内压,计算跨膈压,比较ARDS形成前后跨膈压的变化以及其与胸内压的相关性.方法 5只小家猪,麻醉后置入食管气囊管、胃囊管以及胸管,测定食管压、胃内压以及胸内压,并计算跨膈压.以ARDS形成前所测吸气末压力为自身对照,通过盐水肺灌洗建立ARDS模型;测定ARDS形成后吸气末食管压、胃内压以及胸内压,计算跨膈压,比较跨膈压、胸内压的变化,并分析跨膈压与胸内压之间的相关性.相关程度分析采用线性回归;组间均数比较采用配对t检验.结果 ARDS形成前吸气末食管压、胃内压以及胸内压分别为(7.3±1.9),(25.5±2.4),- (1.23 ±0.21)cmH2O(1 cmH2O =0.098 kPa);ARDS形成后其压力为(4.7±1.4),(31.1±3.1)和- (1.79±0.28)cmH2O;跨膈压A为胃内压与胸内压相减所得,跨膈压B为胃内压与食管压相减所得,跨膈压B相应的由ARDS形成前的(18.2±1.6) cmH2O增加为形成后的(26.4±2.1)cmH2O,这些变化差异具有统计学意义(P<0.05).ARDS形成前胸内压与食管压、跨膈压A和B的r值分别为(0.93±0.025),(0.88 ±0.023)和(0.87±0.37),相关程度很高(P<0.01);ARDS形成后胸内压与食管压、跨膈压A和B的r值分别为值分别为(0.82±0.21),(0.81 ±0.20)和(0.78±0.31),虽较ARDS形成前有所下降,但仍有极高的相关度(P<0.0l).结论 ARDS形成前食管压、跨膈压与胸内压均有较高的相关性;ARDS情况下两者与胸内压的相关程度较ARDS形成前有所降低,但仍有很高的相关性;ARDS形成后跨膈压增加,呼吸做功增加,容易出现呼吸肌疲劳.