Tütüncü A S, Akpir K, Mulder P, Erdmann W, Lachmann B
Department of Anesthesiology, Faculty of Medicine, University of Istanbul, Turkey.
Anesthesiology. 1993 Nov;79(5):1083-93. doi: 10.1097/00000542-199311000-00027.
Respiratory distress syndrome carries a high morbidity and mortality when treated with mechanical ventilation with positive end-expiratory pressure. Perfluorocarbon liquids are employed in liquid ventilation due to low surface tension and high gas solubility. To assess whether intratracheal administration of the perfluorocarbon, perflubron, in combination with conventional mechanical ventilation could be of therapeutic benefit in respiratory distress syndrome, the authors tested the effects of different doses of intratracheal perflubron administration on gas exchange and lung mechanics in adult animals with respiratory failure during a 6-h observation period.
Respiratory failure was induced in 30 rabbits by saline lung lavage (arterial oxygen tension < 100 mmHg at 100% oxygen with the following ventilator settings: tidal volume, 12 ml.kg-1; respiratory frequency, 30 per min; inspiratory/expiratory ratio, 1:2; and positive end-expiratory pressure of 6 cm H2O). Twenty-four rabbits were treated with different perfluorocarbon doses (3, 6, 9, and 12 ml.kg-1), and the remaining six served as controls while mechanical ventilation was continued with the aforementioned settings. Additionally, in ten healthy rabbits who were used as healthy controls, the lungs were mechanically ventilated either alone or in combination with intratracheal perfluorocarbon administration (3 ml.kg-1) for 6 h.
In all treatment groups, arterial oxygen pressure increased significantly (P < 0.0001) in a dose-related fashion (193 +/- 40, 320 +/- 70, 353 +/- 125, and 410 +/- 45 mmHg at 15 min), and peak airway pressures decreased significantly (range, 18-23%; P < 0.0001) from pretreatment values. These findings were in contrast to those for the control group. The improvements were time-dependent in all four tested perfluorocarbon doses. However, the improvements in pulmonary parameters could be extended to 6 h only in groups treated with 9 ml.kg-1 and 12 ml.kg-1 perflubron. At the end of the 6-h period, the data for these two groups showed significantly higher arterial oxygen pressure (230 +/- 84 and 197 +/- 130 mmHg, respectively; P < 0.05) and lower inflation pressures than the pretreatment data for these groups and the data for the control group at 6 h. There were no clinically significant changes in pulmonary parameters in healthy animals due either to mechanical ventilation alone or mechanical ventilation in combination with intratracheal perfluorocarbon administration for 6 h.
The results of this study imply that there is no association between the lung mechanics and gas exchange parameters for mechanical ventilation in combination with intratracheal perfluorocarbon administration. The data suggest that this type of perfluorocarbon administration with conventional mechanical ventilation offers a simple, alternative treatment of respiratory distress syndrome. With this technique, adequate pulmonary gas exchange can be maintained at relatively low airway pressures with high perfluorocarbon doses for several hours.
采用呼气末正压机械通气治疗呼吸窘迫综合征时，其发病率和死亡率较高。全氟化碳液体因其低表面张力和高气体溶解度而用于液体通气。为评估气管内给予全氟碳化合物全氟溴烷联合传统机械通气对呼吸窘迫综合征是否具有治疗益处，作者在6小时观察期内测试了不同剂量气管内给予全氟溴烷对成年呼吸衰竭动物气体交换和肺力学的影响。
通过盐水肺灌洗诱导30只兔子发生呼吸衰竭（在以下通气设置下，吸入100%氧气时动脉血氧分压<100 mmHg：潮气量，12 ml·kg-1；呼吸频率，每分钟30次；吸呼比，1:2；呼气末正压6 cm H2O）。24只兔子接受不同剂量的全氟碳化合物（3、6、9和12 ml·kg-1）治疗，其余6只作为对照，同时以上述设置继续进行机械通气。此外，将10只健康兔子作为健康对照，其肺单独进行机械通气或联合气管内给予全氟碳化合物（3 ml·kg-1）通气6小时。
在所有治疗组中，动脉血氧压力均显著升高（P<0.0001），呈剂量相关方式（15分钟时分别为193±40、320±70、353±125和410±45 mmHg），且气道峰值压力较治疗前值显著降低（范围为18%-23%；P<0.0001）。这些结果与对照组相反。在所有四个测试的全氟碳化合物剂量中，改善情况均呈时间依赖性。然而，仅在接受9 ml·kg-1和12 ml·kg-1全氟溴烷治疗的组中，肺参数的改善可持续至6小时。在6小时观察期结束时，这两组的数据显示动脉血氧压力显著更高（分别为230±84和197±130 mmHg；P<0.05），且充气压力低于这些组治疗前数据以及对照组6小时时的数据。健康动物单独进行机械通气或联合气管内给予全氟碳化合物通气6小时后，肺参数无临床显著变化。
本研究结果表明，气管内给予全氟碳化合物联合机械通气时，肺力学与气体交换参数之间无关联。数据表明，这种全氟碳化合物与传统机械通气联合的给药方式为呼吸窘迫综合征提供了一种简单的替代治疗方法。采用该技术，使用高剂量全氟碳化合物时，可在相对较低的气道压力下维持数小时的充分肺气体交换。
