Uhlig T, Wildhaber J H, Eber E, Sly P D
Division of Clinical Sciences, Princess Margaret Hospital for Children, Perth, Western Australia.
Pediatr Res. 1997 Oct;42(4):533-8. doi: 10.1203/00006450-199710000-00019.
Eleven open-chest piglets were studied to examine the effects of vascular engorgement on partitioned airway and lung tissue mechanics, and to investigate the role of vagal denervation on lung function during engorgement. Alveolar pressure was measured using alveolar capsules. Pulmonary elastance (EL) and resistance (RL), airway (Raw), and tissue (Vti) resistance were calculated during mechanical ventilation. Acute fluid administration with polygeline (10 mL/kg boluses up to a total of 30 mL/kg) resulted in an increase of RL with increases in both Raw and Vti. Vti rose 2-3-fold in comparison with Raw. To increase left atrial pressure, a balloon catheter was inserted into the left atrium of the heart and inflated with different volumes. The responses of EL, RL, Raw and Vti were comparable to those with acute fluid load. Alterations in pulmonary mechanics were closely correlated to mean pulmonary artery blood pressure. In another six animals the effect of vagotomy on vascular engorgement was studied. Vagotomy did not alter baseline airway or tissue mechanics. Furthermore, vagotomy did not influence the change of pulmonary mechanics to fluid load or increase of left atrial pressure. Our data indicate that in young piglets vascular engorgement causes alterations in airway and lung tissue mechanics that are not dependent on vagal influences.
对11只开胸仔猪进行了研究，以检查血管充血对分隔气道和肺组织力学的影响，并研究迷走神经切断在充血期间对肺功能的作用。使用肺泡囊测量肺泡压力。在机械通气期间计算肺弹性（EL）和阻力（RL）、气道阻力（Raw）和组织阻力（Vti）。用聚明胶肽进行急性液体输注（10 mL/kg推注，总量达30 mL/kg）导致RL增加，同时Raw和Vti均增加。与Raw相比，Vti升高了2 - 3倍。为了增加左心房压力，将球囊导管插入心脏左心房并用不同体积充气。EL、RL、Raw和Vti的反应与急性液体负荷时的反应相当。肺力学改变与平均肺动脉血压密切相关。在另外6只动物中研究了迷走神经切断对血管充血的影响。迷走神经切断未改变基线气道或组织力学。此外，迷走神经切断不影响肺力学对液体负荷或左心房压力增加的变化。我们的数据表明，在幼龄仔猪中，血管充血会导致气道和肺组织力学改变，且这些改变不依赖于迷走神经的影响。
