Portal de Periódicos da CAPES

Neurally-Adjusted Ventilatory Assist for Noninvasive Ventilation via a Helmet in Subjects With COPD Exacerbation: A Physiologic Study

2019; American Association for Respiratory Care; Volume: 64; Issue: 5 Linguagem: Inglês

10.4187/respcare.06502

1943-3654

Federico Longhini, Ling Liu, Chun Pan, Jianfeng Xie, Gianmaria Cammarota, Andrea Bruni, Eugenio Garofalo, Yi Yang, Paolo Navalesi, Haibo Qiu,

Cardiac Arrest and Resuscitation

BACKGROUND: In patients with COPD exacerbation, noninvasive ventilation (NIV) is strongly recommended. NIV is generally delivered by using patient triggered and flow-cycled pressure support through a face mask. A specific method to generate neurally-controlled pressure support has been shown to improve comfort and patient-ventilator interaction. In addition, the helmet interface was better tolerated by patients compared with a face mask. Herein, we compared neurally-controlled pressure support through a helmet with pressure support through a face mask with respect to subject comfort, breathing pattern, gas exchange, pressurization and triggering performance, and patient-ventilator synchrony. METHODS: Two 30-min trials of NIV were randomly delivered to 10 subjects with COPD exacerbation redundant: (1) pressure support through a face mask with inspiratory pressure support of ≥8 cm H 2 O to obtain a tidal volume of 6–8 mL/kg of ideal body weight; and (2) NAVA through a helmet, setting the neurally-adjusted ventilatory assist level at 15 cm H 2 O/μV, with an upper airway pressure limit to obtain the same overall airway pressure applied during pressure support through a face mask. We assessed subject comfort, breathing frequency, respiratory drive, arterial blood gases, pressure-time product (PTP) of the first 300 ms and 500ms after initiation of subject effort, inspiratory trigger delay, and rate of asynchrony determined as the asynchrony index. RESULTS: Median and interquartile range NAVA through a helmet improved comfort (7.0 [6.0–8.0]) compared with pressure support through a face mask (5.0 [4.7–5.2], P = .005). The breathing pattern was not different between the methods. Respiratory drive was slightly, although not significantly, reduced ( P = .19) during NAVA through a helmet in comparison with pressure support through a face mask. Gas exchange was also not different between the trials. The PTP of the first 300 ms ( P = .92) and PTP of the first 500 ms ( P = .08) were not statistically different between trials, whereas triggering performance, patient-ventilator interaction, and synchrony were all improved by NAVA through a helmet compared with pressure support through a face mask. CONCLUSIONS: In the subjects with COPD with exacerbation, NAVA through a helmet improved comfort, triggering performance, and patient-ventilator synchrony compared with pressure support through a face mask.