Noninvasive ventilation: an emerging supportive technique for the emergency department.

Noninvasive ventilation (NIV) is the provision of ventilatory support to a spontaneously breathing patient without endotracheal intubation. In this review, we detail concerns related to endotracheal intubation and summarize the physiologic effects and clinical application of NIV. We then address the use of NIV in 5 conditions of particular interest to the practitioner of emergency medicine: exacerbated chronic obstructive lung disease, severe asthma, patients who are not candidates for endotracheal intubation, pneumonia, and pulmonary edema.