In:
Pediatric Pulmonology, Wiley, Vol. 52, No. 11 ( 2017-11), p. 1455-1460
Abstract:
Nasal high‐frequency oscillatory ventilation (nHFOV) is a novel mode of non‐invasive ventilation used in neonates. However, upper airway obstructions due to viscous secretions have been described as specific adverse effects. We hypothesized that high‐frequency oscillations reduce air humidity in the oropharynx, resulting in upper airway desiccation. Therefore, we aimed to investigate the effects of nHFOV ventilatory settings on oropharyngeal gas conditions. Methods NHFOV or nasal continuous positive airway pressure (nCPAP) was applied, along with heated humidification, to a previously established neonatal bench model that simulates oropharyngeal gas conditions during spontaneous breathing through an open mouth. A digital thermo‐hygro sensor measured oropharyngeal temperature (T) and humidity at various nHFOV frequencies (7, 10, 13 Hz), amplitudes (10, 20, 30 cmH 2 O), and inspiratory‐to‐expiratory (I:E) ratios (25:75, 33:66, 50:50), and also during nCPAP. Results Relative humidity was always 〉 99%, but nHFOV resulted in lower mean T and absolute humidity (AH) in comparison to nCPAP ( P 〈 0.001). Specifically, decreasing the nHFOV frequency and increasing nHFOV amplitude caused a decline in T and AH ( P 〈 0.001). Mean T and AH were highest during nCPAP (T 34.8 ± 0.6°C, AH 39.3 ± 1.3 g · m −3 ) and lowest during nHFOV at a frequency of 7 Hz and an amplitude of 30 cmH 2 O (T 32.4 ± 0.3°C, AH 34.7 ± 0.5 g · m −3 ). Increasing the I:E ratio also reduced T and AH ( P = 0.03). Conclusion Intensified nHFOV settings with low frequencies, high amplitudes, and high I:E ratios may place infants at an increased risk of upper airway desiccation. Future studies should investigate strategies to optimize heated humidification during nHFOV.
Type of Medium:
Online Resource
ISSN:
8755-6863
,
1099-0496
Language:
English
Publisher:
Wiley
Publication Date:
2017
detail.hit.zdb_id:
1491904-7
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