Tracheal gas insufflation-augmented continuous positive airway pressure in a spontaneously breathing model of neonatal respiratory distress
Tracheal gas insufflation-augmented continuous positive airway pressure in a spontaneously breathing model of neonatal respiratory distress
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DOI：
10.1002/ppul.20094
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发表时间：
2004-11-01
影响因子：
3.1
通讯作者：
Touch, SM
中科院分区：
文献类型：
--
作者：
Miller, TL;Blackson, TJ;Touch, SM
新生儿呼吸窘迫综合征（RDS）的特征是呼吸困难和气体交换不良，通常需要呼吸支持。持续气道正压通气（CPAP）是一种优选的干预措施，通过维持肺容量复张来支持自发性复张，同时通过维持呼气末压力来防止呼气过程中的去复张。然而，CPAP期间的CO2潴留通常导致需要机械通气。由于气管气体吹入（TGI）通过减少假体死腔促进CO2消除，我们假设TGI与CPAP联合使用可能减少对更具侵入性治疗的需求。本研究的目的是评价TGI与CPAP在急性肺损伤自主呼吸模型中气体交换和肺力学方面的生理作用。将19只自主呼吸的新生猪（2.4+/-0.4 kg）麻醉、镇静、仪器化，并置于5 cmH 2 O的CPAP上。所有仔猪静脉注射油酸（0.08 ml/kg），然后随机接受CPAP与TGI（TGI; n = 9）或CPAP单独（对照; n = 10）。在方案期间，FiO（2）每15分钟滴定0.05，以维持SaO（2）> 93%。损伤后30分钟，每隔1小时对生命体征、动脉血气、肺力学和胸腹运动（TAM）进行评价，持续4小时。4小时测量后，处死仔猪，对肺部进行大体检查。开始治疗后，我们发现TGI组的PaCO 2较低（33.1 +/- 5.0 vs. 47.0 +/- 10.3 mmHg; P < 0.01），而氧合指数（PaO 2、SaO（2）、a/A比值; P< 0.01）高于对照组动物。随后，pH值更高（7.45 +/- 0.08 vs. 7.36 +/- 0.08; P < 0.01），更接近TGI的基线值。到4小时时，TGI组FiO（2）滴定较低（0.37 +/- 0.06 vs. 0.49 +/- 0.15; P< 0.05），通气完成时每分钟通气量（MV）低于对照组（445 +/- 113 vs. 581 +/- 223 ml/kg/min; P< 0.01）。TGI组的呼吸顺应性高于对照组（0.76 +/- 0.13 vs. 0.63 +/- 0.11 ml/cmH 2 O/kg; P < 0.01），而阻力和TAM组间相似。我们的结论是，使用TGI与CPAP治疗RDS的结果，改善气体交换和肺力学。因此，TGI增强的CPAP可以通过减少CO2潴留来防止婴儿需要更多的侵入性通气。(C)2004 Wiley-Liss，Inc.
Respiratory distress syndrome (RDS) in neonates is characterized by labored breathing and poor gas exchange, often requiring ventilatory support. Continuous positive airway pressure (CPAP) is a preferred intervention to support spontaneous ventilatory efforts by sustaining lung volume recruitment, while it prevents derecruitment during exhalation by maintaining end-expiratory pressure. However, CO2 retention during CPAP often results in the need for mechanical ventilation. Since tracheal gas insufflation (TGI) promotes CO2 elimination by reducing prosthetic dead space, we hypothesized that TGI used with CPAP may reduce the need for more invasive therapies. The objective of this study was to evaluate the physiologic effect of TGI with CPAP in a spontaneously breathing model of acute lung injury with respect to gas exchange and pulmonary mechanics. Nineteen spontaneously breathing neonatal pigs (2.4+/-0.4 kg) were anesthetized, sedated, instrumented, and placed on CPAP at 5 cmH(2)O. All piglets were injured with intravenous oleic acid (0.08 ml/kg), and then randomized to receive CPAP with TGI (TGI; n = 9) or CPAP alone (control; n = 10). FiO(2) was titrated at 0.05 every 15 min during the protocol to maintain SaO(2) > 93%. Vital signs, arterial blood gases, pulmonary mechanics, and thoracoabdominal motion (TAM) were evaluated 30 min after injury and at 1-hr intervals for 4 hr. Following the 4-hr measurement, the piglets were sacrificed and the lungs were grossly examined. After initiation of treatment, we found that the PaCO2 was lower (33.1 +/- 5.0 vs. 47.0 +/- 10.3 mmHg; P < 0.01), while the oxygenation indices were greater (PaO2, SaO(2), a/A ratio; P< 0.01) in the TGI group than with control animals. Subsequently, the pH was greater (7.45 +/- 0.08 vs. 7.36 +/- 0.08; P < 0.01) and closer to baseline values with TGI. By 4 hr, the FiO(2) was titrated lower (0.37 +/- 0.06 vs. 0.49 +/- 0.15; P< 0.05) and ventilation was accomplished with a lower minute ventilation (MV) in the TGI group than in the control group (445 +/- 113 vs. 581 +/- 223 ml/kg/min; P< 0.01). Respiratory compliance was greater with TGI than control (0.76 +/- 0.13 vs. 0.63 +/- 0.11 ml/cmH(2)O/kg; P < 0.01), whereas resistance and TAM were similar between groups. We conclude that the use of TGI with CPAP in the treatment of RDS results in improved gas exchange and pulmonary mechanics. As such, TGI-augmented CPAP may prevent infants from requiring more invasive ventilation by reducing CO2 retention. (C) 2004 Wiley-Liss, inc.