Non-invasive ventilation in the ED: Whom, When, How?

Abstract

As emergency physicians, we encounter patients suffering from either hypoxemic and/or hypercarbic respiratory problems on a daily basis. A stepwise approach to solving this problem seems logical from an emergency medicine perspective. Current literature supports the notion that NIV decreases endotracheal intubation rates and, mortality in select patient populations. The key to the success of NIV is patient cooperation and support for the care givers. In this narrative review, non-invasive ventilation (NIV) is discussed in terms of modes of delivery, interface and patient selection, as well as practical considerations.

Fig. 1

CPAP: continuous positive airway pressure. A single pressure is applied during inspiration and expiration.

Fig. 2

BPAP IPAP: Inspiratory positive airway pressure, EPAP: Expiratory positive airway pressure, PS: Pressure Support. Here inspiration is triggered by patient effort and intra alveolar pressure increases; at the end of the inspiration a constant pressure (EPAP) is applied during expiration.

Fig. 3

A-Oronasal mask, B- Full face mask.

Fig. 4

Tracings of different types of asynchrony (with the permission of Springer-Verlag). V: Volume, Paw: Airway pressure, EMGdi: Electromyography of the diaphragm.