Elshafei Ahmad A, Fink James B, Li Jie
Division of Respiratory Care, Department of Cardiopulmonary Sciences, Rush University Medical Center, Chicago, Illinois.
Aerogen Pharma Corp, San Mateo, California.
Respir Care. 2022 Apr;67(4):415-420. doi: 10.4187/respcare.08914. Epub 2021 Sep 2.
As the use of continuous high-frequency oscillation combined with nebulization during mechanical ventilation becomes more prevalent clinically, it is important to evaluate its aerosol delivery efficacy.
A bench study was conducted that simulated 2 adult and 2 pediatric conditions. A continuous high-frequency oscillation device integrated into the inspiratory limb of a conventional critical care ventilator was attached to an endotracheal tube (ETT) with a collection filter and test lung. High-frequency oscillation with high-flow setting was used with jet nebulizers attached to the manifold, and a vibrating mesh nebulizer placed between the ETT and the ventilator circuit versus at the inlet of the humidifier. Albuterol (2.5 mg in 3 mL) was nebulized for each condition (no. = 3). The drug was eluted from the collection filter and assayed with ultraviolet spectrophotometry (276 nm).
During continuous high-frequency oscillation, the mean inhaled dose with jet nebulizers was low (<2% with the adult settings and <1% with the pediatric settings). Across both adult and pediatric conditions, when the vibrating mesh nebulizer was placed between the ETT and the Y-piece during continuous high-frequency oscillation, the inhaled dose was higher than with the placement of the vibrating mesh nebulizer at the inlet of the humidifier, median 11.1% (IQR 7.0%-13.7%) median 6.0% (IQR 3.9%-7.2%) ( = .002) respectively, but still lower than the inhaled dose with the vibrating mesh nebulizer placed at the inlet of the humidifier with continuous high-frequency oscillation off, median 22.7% (IQR 19.5%-25.4%) versus median 11.1% (IQR 7.0%-13.7%) ( < .001). The inhaled dose with the 10-year-old scenario was higher than with the 5-year-old scenario in all settings except aerosol delivery via continuous high-frequency oscillation.
During invasive mechanical ventilation with continuous high-frequency oscillation, aerosol delivery with jet nebulizers in the manifold resulted in a marginal inhaled dose. The vibrating mesh nebulizer at the ETT during continuous high-frequency oscillation delivered 6-fold more aerosol than did the jet nebulizer, while delivering only half of the inhaled dose with the vibrating mesh nebulizer placed at the inlet of the humidifier without continuous high-frequency oscillation.
随着机械通气期间持续高频振荡联合雾化的应用在临床上越来越普遍，评估其气溶胶输送效果很重要。
进行了一项实验台研究，模拟了2种成人和2种儿童情况。将集成在传统重症监护呼吸机吸气支路上的持续高频振荡装置连接到带有收集过滤器和测试肺的气管内导管（ETT）上。在高流量设置下进行高频振荡，同时在歧管上连接喷射雾化器，并将振动筛网雾化器放置在ETT与呼吸机回路之间以及加湿器入口处进行对比。每种情况（n = 3）均雾化沙丁胺醇（3 mL中含2.5 mg）。药物从收集过滤器中洗脱出来，并用紫外分光光度法（276 nm）进行测定。
在持续高频振荡期间，使用喷射雾化器时的平均吸入剂量较低（成人设置下<2%，儿童设置下<1%）。在成人和儿童两种情况下，当在持续高频振荡期间将振动筛网雾化器放置在ETT与Y形管之间时，吸入剂量高于将振动筛网雾化器放置在加湿器入口处时，中位数分别为11.1%（IQR 7.0%-13.7%）和6.0%（IQR 3.9%-7.2%）（P = .002），但仍低于在持续高频振荡关闭时将振动筛网雾化器放置在加湿器入口处时的吸入剂量，中位数分别为22.7%（IQR 19.5%-25.4%）和11.1%（IQR 7.0%-13.7%）（P < .001）。在除通过持续高频振荡进行气溶胶输送之外的所有设置中，10岁情况的吸入剂量均高于5岁情况。
在进行持续高频振荡的有创机械通气期间，歧管中的喷射雾化器进行气溶胶输送时吸入剂量有限。持续高频振荡期间放置在ETT处的振动筛网雾化器输送的气溶胶比喷射雾化器多6倍，而在无持续高频振荡时放置在加湿器入口处的振动筛网雾化器输送的吸入剂量只有前者的一半。
