Manaligod J M, Bendel-Stenzel E M, Meyers P A, Bing D R, Connett J E, Mammel M C
Infant Pulmonary Research Center, Children's Hospital and Clinics-St. Paul, MN 55102, USA.
Chest. 2000 Jan;117(1):184-90. doi: 10.1378/chest.117.1.184.
To determine the effects of different levels of positive end-expiratory pressure (PEEP) during partial liquid ventilation (PLV) on gas exchange, lung compliance, and end-expiratory lung volume (EELV).
Prospective animal study.
Animal physiology research laboratory.
Nine piglets.
Animals underwent saline solution lavage to produce lung injury. Perflubron was instilled via the endotracheal tube in a volume estimated to represent functional residual capacity. The initial PEEP setting was 4 cm H(2)O, and stepwise changes in PEEP were made. At 30-min intervals, the PEEP was increased to 8, then 12, then decreased back down to 8, then 4 cm H(2)O.
After 30 min at each level of PEEP, arterial blood gases, aortic and central venous pressures, heart rates, dynamic lung compliance, and changes in EELV were recorded. Paired t tests with Bonferroni correction were used to evaluate the data. There were no differences in heart rate or mean BP at the different PEEP levels. CO(2) elimination and oxygenation improved directly with the PEEP level and mean airway pressure (Paw). Compliance did not change with increasing PEEP, but did increase when PEEP was lowered. EELV changes correlated directly with the level of PEEP.
As previously reported during gas ventilation, oxygenation and CO(2) elimination vary directly with PEEP and proximal Paw during PLV. EELV also varies directly with PEEP. Dynamic lung compliance, however, improved only when PEEP was lowered, suggesting an alteration in the distribution of perflubron due to changes in pressure-volume relationships.
确定部分液体通气(PLV)期间不同水平的呼气末正压(PEEP)对气体交换、肺顺应性和呼气末肺容积(EELV)的影响。
前瞻性动物研究。
动物生理学研究实验室。
9只仔猪。
对动物进行盐溶液灌洗以造成肺损伤。通过气管内导管滴入全氟溴烷,其体积估计代表功能残气量。初始PEEP设置为4 cm H₂O,并对PEEP进行逐步改变。每隔30分钟,将PEEP增加到8,然后是12,然后再降至8,最后降至4 cm H₂O。
在每个PEEP水平维持30分钟后,记录动脉血气、主动脉和中心静脉压、心率、动态肺顺应性以及EELV的变化。使用经Bonferroni校正的配对t检验来评估数据。在不同的PEEP水平下,心率或平均血压没有差异。CO₂清除和氧合直接随PEEP水平和平均气道压(Paw)改善。顺应性不会随PEEP增加而改变,但在PEEP降低时会增加。EELV变化与PEEP水平直接相关。
如先前在气体通气期间所报道的,在PLV期间,氧合和CO₂清除随PEEP和近端Paw直接变化。EELV也随PEEP直接变化。然而,动态肺顺应性仅在PEEP降低时改善,这表明由于压力-容积关系的变化,全氟溴烷的分布发生了改变。