Müller E E, Kolobow T, Mandava S, Jones M, Vitale G, Aprigliano M, Yamada K
Section on Pulmonary and Cardiac Assist Devices, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland 20892.
Pediatr Res. 1993 Nov;34(5):606-10. doi: 10.1203/00006450-199311000-00010.
We wished to determine in a laboratory animal model how much residual lung was needed to sustain total gas exchange. In a series of young, healthy lambs weighing approximately 10 kg that were sedated and paralyzed, we progressively excluded from gas exchange all the left lung (a total of 43%), plus the right lower and cardiac lobes (81%), plus the right middle lobe (87.5%). In some studies, the respective lobes were surgically removed; in others, the bronchi and the pulmonary arteries to the respective lobes were ligated. We provided pulmonary ventilation using the pressure control mode (Servo 900 C) at a tidal volume of 20 mL/kg multiplied by the fraction of the remaining lungs, a respiratory rate up to 120/min, a peak inspiratory pressure of 12-15 cm H2O, and a positive end-expiratory pressure of 3 cm H2O. Those lambs with at least both the right upper lobe (RUL) and right middle lobe remaining (19% of total lungs) were weaned to room air on mechanical ventilation within 48 h. Ventilating RUL (12.5% of remaining lung) with the same ventilator required a substantially higher tidal volume and peak inspiratory pressure to result in adequate alveolar ventilation but led to respiratory failure and death within 8 h. We then applied a newly developed system of intratracheal pulmonary ventilation to ventilate the RUL (12.5% of remaining lung) alone. A continuous flow of humidified mixture of air and oxygen was directly passed into the trachea at the level of the carina through a diffuser at a tidal volume of 2.5 mL/kg. A single valve controlled expiration and respiratory rate.(ABSTRACT TRUNCATED AT 250 WORDS)
我们希望在一种实验动物模型中确定维持全部气体交换需要多少残余肺组织。在一系列体重约10千克的年轻健康羔羊中，使其镇静并麻痹，我们逐步将左肺（共43%）、右肺下叶和心叶（81%）以及右中叶（87.5%）全部排除在气体交换之外。在一些研究中，相应肺叶通过手术切除；在另一些研究中，相应肺叶的支气管和肺动脉被结扎。我们使用压力控制模式（Servo 900 C）进行肺通气，潮气量为20 mL/kg乘以剩余肺组织的比例，呼吸频率最高为120次/分钟，吸气峰压为12 - 15 cm H₂O，呼气末正压为3 cm H₂O。那些至少保留右肺上叶（RUL）和右中叶（占全肺的19%）的羔羊在48小时内通过机械通气撤机至室内空气环境。用同一台呼吸机对RUL（占剩余肺组织的12.5%）进行通气时，需要更高的潮气量和吸气峰压才能实现足够的肺泡通气，但会在8小时内导致呼吸衰竭和死亡。然后我们应用一种新开发的气管内肺通气系统单独对RUL（占剩余肺组织的12.5%）进行通气。一股持续流动的空气和氧气的湿化混合气体通过一个扩散器在隆突水平直接进入气管，潮气量为2.5 mL/kg。通过一个单向阀控制呼气和呼吸频率。（摘要截断于250字）
