一种新型、多功能的带阀持气室，用于向新生儿和幼儿输送吸入性药物：输送方式的实验室模拟。

A novel, versatile valved holding chamber for delivering inhaled medications to neonates and small children: laboratory simulation of delivery options.

机构信息

Center for Developmental Therapeutics, Seattle Children's Research Institute, Washington, USA.

出版信息

Respir Care. 2010 Apr;55(4):419-26.

DOI:

PMID:20406509

Abstract

BACKGROUND

Delivery of bronchodilator to infants and small children from a pressurized metered-dose inhaler with valved holding chamber (pMDI-VHC) is limited by airway narrowness, short respiratory cycle time, and small tidal volume (V(T)). There is a need for a versatile, efficient VHC, given the variety of treatment modalities.

METHODS

We tested the AeroChamber Mini VHC (the internal geometry of which is optimized for aerosol delivery, and which accepts a pMDI canister that has a dose counter) in experiments to determine differences in the delivery of hydrofluoroalkane-propelled albuterol (90 microg/actuation) during: mechanical ventilation via endotracheal tube (ETT); manual resuscitation via ETT; and spontaneous breathing via face mask. We tested 5 units of the AeroChamber Mini VHC per test. We simulated the tidal breathing of a premature neonate (V(T) 6 mL), a term neonate (V(T) 20 mL), and a child approximately 2 years old (V(T) 60 mL). We collected the aerosol on an electret filter and quantitatively assayed for albuterol.

RESULTS

The total emitted mass of albuterol per actuation that exited the VHC was marginally greater during spontaneous breathing (12.1 +/- 1.8 microg) than during manual resuscitation (10.0 +/- 1.1 microg) (P = .046). Albuterol delivery via mechanical ventilation, though comparable with the premature-neonate model (3.3 +/- 1.2 microg), the term-neonate model (3.8 +/- 2.1 microg), and the 2-y-old-child model (4.2 +/- 2.3 microg) (P = .63), was significantly lower than in the spontaneous-breathing and manual-resuscitation models (P < .001). In the neonatal models the total emitted mass was similar with the spontaneous-breathing model (6.0 +/- 1.0 microg with the premature-neonate model, 10.5 +/- 0.7 microg with the term-neonate model) and the manual-resuscitation model (5.5 +/- 0.3 microg premature-neonate model, 10.7 +/- 0.9 microg term-neonate model) (P > or = .46 via one-way analysis of variance).

CONCLUSION

The reduced delivery of albuterol during mechanical ventilation (compared to during spontaneous breathing and manual resuscitation via ETT) was probably associated with the saturated atmosphere in the breathing circuit (37 degrees C, relative humidity > 99%), compared to the ambient air (22 +/- 1 degrees C, 44 +/- 7% relative humidity). The AeroChamber Mini VHC may provide a versatile alternative to VHCs that are designed exclusively for one aerosol treatment modality.

摘要

背景

由于气道狭窄、呼吸周期短以及潮气量小，从带活瓣的储雾罐的压力定量气雾剂吸入器（pMDI-VHC）输送支气管扩张剂对婴儿和幼儿有限制。鉴于各种治疗方式的需要，需要一种通用、高效的 VHC。

方法

我们通过实验测试了 Aer oChamber Mini VHC（其内部几何形状经过优化，可输送气雾剂，并且可接受带有剂量计数器的 pMDI 罐），以确定在以下情况下输送氢氟烷烃推进的沙丁胺醇（每喷 90 微克）的差异：通过气管内管（ETT）进行机械通气；通过 ETT 进行手动复苏；通过面罩进行自主呼吸。我们对每个测试测试了 5 个 Aer oChamber Mini VHC 单位。我们模拟了早产儿（V（T）6 毫升）、足月新生儿（V（T）20 毫升）和大约 2 岁儿童（V（T）60 毫升）的潮式呼吸。我们将气雾剂收集在驻极体过滤器上，并对沙丁胺醇进行定量分析。

结果

与手动复苏（10.0 ± 1.1 微克）相比，自主呼吸时（12.1 ± 1.8 微克）每喷沙丁胺醇的总发射质量略有增加（P =.046）。尽管通过机械通气输送的沙丁胺醇与早产儿模型（3.3 ± 1.2 微克）、足月新生儿模型（3.8 ± 2.1 微克）和 2 岁儿童模型（4.2 ± 2.3 微克）相当（P =.63），但与自主呼吸和手动复苏模型相比，其输送量明显较低（P <.001）。在新生儿模型中，总发射质量与自主呼吸模型相似（早产儿模型 6.0 ± 1.0 微克，足月新生儿模型 10.5 ± 0.7 微克）和手动复苏模型（早产儿模型 5.5 ± 0.3 微克，足月新生儿模型 10.7 ± 0.9 微克）（通过单向方差分析 P >.46）。

结论

与自主呼吸和通过 ETT 进行手动复苏相比，机械通气期间沙丁胺醇的输送减少（与自主呼吸和手动复苏相比）可能与呼吸回路中的饱和气氛（37°C，相对湿度> 99%）有关，而不是与环境空气（22 ± 1°C，44 ± 7% 相对湿度）。Aer oChamber Mini VHC 可能为专门为一种气雾剂治疗方式设计的 VHC 提供通用替代方案。