Bronchodilator Delivery During Simulated Pediatric Noninvasive Ventilation

Abstract

BACKGROUND: Noninvasive ventilation (NIV) is usually applied using bi-level positive airway pressure devices, and many of these devices use a single-limb patient circuit with an integrated leak port to purge the circuit of exhaled carbon dioxide. Sometimes bronchodilator therapy is indicated in pediatric patients, but there have been no studies of the optimal nebulizer position, with respect to leak, during pediatric NIV. We hypothesized that there would be no differences in albuterol delivery with a vibrating-mesh nebulizer between 3 different positions/exhalation leak valve combinations in the patient circuit during simulated pediatric NIV. METHODS: A simulated upper airway model was attached to a lung model that simulated spontaneous breathing. A noninvasive ventilator equipped with heated wire circuit and heated humidifier was attached to the lung model via a pediatric oronasal mask. Albuterol (5 mg) was delivered with a vibrating-mesh nebulizer, at 3 different circuit position/leak condition combinations: prior to the humidifier and leak valve; between the humidifier and leak valve; and integrated within the mask and after the leak. Albuterol was captured on a filter and quantified with chromatography. RESULTS: Greater albuterol mass was delivered to the filter with the nebulizer integrated into the mask than at any other testing condition (P < .001). In the conditions where the nebulizer was placed prior to the exhalation leak valve, greater drug delivery was observed when the nebulizer was placed proximal to the mask (position 2) than when placed prior to the humidifier (position 3, P ‫؍‬ .002). CONCLUSIONS: Albuterol delivery during simulated pediatric NIV was affected by the position of the nebulizer in relation to the expiratory leak valve and the nebulizer's distance from the filter. A vibrating-mesh nebulizer placed intra-mask may provide a better alternative for medication delivery than those previously used during pediatric NIV.

Radioaerosol Pulmonary Deposition Using Mesh and Jet Nebulizers During Noninvasive Ventilation in Healthy Subjects

“…On the other hand, counts registered in the horizontal differences showed that intragroup radioaerosol deposition was more significant when comparing central and peripheral regions in both lungs for each group, demonstrating that substantial aerosol reached the central areas, which should be relevant during inhalation of anticholinergic bronchodilators, with a higher concentration of bronchodilator receptors in the central airways. [37][38][39] According to Branconnier and Hess,20 positioning inhalers between the leak port and mask is more effective in delivering a higher amount of aerosol into the lungs. This has been confirmed with both jet and vibrating mesh nebulizers by Abdelrahim et al 10 The effect of nebulizer position during NIV was confirmed by White et al, 39 who reported 2-fold greater deposition with the NIVO placed between the circuit leak and patient airway compared with the Aeroneb Solo mesh nebulizer placed between the ventilator and humidifier and between the humidifier and leak port in a pediatric single-limb circuit.…”

“…[37][38][39] According to Branconnier and Hess,20 positioning inhalers between the leak port and mask is more effective in delivering a higher amount of aerosol into the lungs. This has been confirmed with both jet and vibrating mesh nebulizers by Abdelrahim et al 10 The effect of nebulizer position during NIV was confirmed by White et al, 39 who reported 2-fold greater deposition with the NIVO placed between the circuit leak and patient airway compared with the Aeroneb Solo mesh nebulizer placed between the ventilator and humidifier and between the humidifier and leak port in a pediatric single-limb circuit. It should be noted that the NIVO and Solo use a similar mesh with a similar range of aerosol characteristics.…”

Clinical Controversies in Aerosol Therapy for Infants and Children

“…One study 84 showed greater albuterol mass delivered to a spontaneously breathing pediatric airway/lung model with the NIVO nebulizer integrated into the mask compared with the Aeroneb Solo vibrating mesh nebulizer (Aerogen, Mountain View, California) placed at multiple locations in the circuit. When the vibrating mesh nebulizer was placed before the exhalation leak valve, greater drug delivery was observed when the nebulizer was placed closer to the leak valve than when placed before the humidifier.…”

Aerosol Therapy During Noninvasive Ventilation or High-Flow Nasal Cannula

“…An in vitro study was conducted by White et al 13 to evaluate the optimal nebulizer position of a mesh nebulizer during pediatric NIV. An upper-airway model was attached to a lung model that simulated spontaneous breathing.…”