呼气末正压对急性呼吸窘迫综合征患者胃黏膜pH的影响

目的 对不同大小的呼气末正压 (PEEP)下的急性呼吸窘迫综合征 (ARDS)患者的胃黏膜pH(pHi)进行检测 ,间接了解PEEP对内脏血供的影响。 方法 5 1例ARDS患者均在ARDS确诊后 2 4h内应用呼吸机 ,每个患者PEEP值均从 5cmH2 O开始 (PEEPbaseline) ,以2cmH2 O速率上调 ,直到最高PEEP(PEEPmax)。应用TRIP -NGS导管检测pHi。在每一PEEP通气后 45min测量或计算以下参数 :心输出量 ;中心静脉压 ;平均动脉压 ;动脉氧分压 ;肺动脉楔入压 ;PEEP ;pHi;平均气道压 ;气道峰压。取动脉血气PaO2 最高时的PEEP设为最优PEEP(PEEPopt)。基础PEEP、最优PEEP、最大PEEP之间数据进行比较。 结果 随着PEEP的升高 ,患者气道峰压和平均压均有升高 (P <0 .0 1) ,但MAP ,CVP ,PCWP ,CO ,CI等血流动力学参数没有明显升高 (P >0 .0 5 )pHi在不同的PEEP值亦无明显改变。 结论 在最大PEEP之前 ,随着PEEP的升高 ,氧合的改善弥补了少量的心输出量的减少 ,并不会对组织的灌注造成影响。

Objective To explore the influence of positive end expiratory pressure(PEEP) on splanchna hemodynamics in acute respiratory distress syndrome(ARDS) patients by detecting gastric mucous membrane PH. Methods 51 ARDS patients were given respirator treatment after final diagnosis in 24 hours. The PEEP of each patient started from 5cm H 2O and up-regulated at 2cm H 2O rate of speed until at PEEPmax. The TRIP-NGS duct was used to detect PHi. The parameters of cardiac output(CO), central venous pressure(CVP), mean arterial pressure(MAP), artierial partial pressure of oxygen(APPO), pulmonary artery wedge pressure(PAWP), PEEP, Phi, mean airway pressure and airway cusp pressure(ACP) were tested after 45min PEEP. The PEEPopt was marked when the PaCO 2 was at its highest and the data of PEEP baseline, PEEPopt and most PEEP were compared to each other. Results: As the PEEP step-up, the ACP and mean airway pressure all increased(P<0.01), but the hemodynamic parameters of MAP,CVP,PCWP,CO,CI had not significant difference(P>0.05). The PHi value was also had not significant difference at different PEEP. Conclusion Before the most PEEP, the improvement of oxygenation made up some CO decrease with the PEEP step-up, which did not affect the organ instilling.