Noninvasive ventilation in acute respiratory failure

Abstract

After the institution of positive-pressure ventilation, the use of noninvasive ventilation (NIV) through an interface substantially increased. The first technique was continuous positive airway pressure; but, after the introduction of pressure support ventilation at the end of the 20th century, this became the main modality. Both techniques, and some others that have been recently introduced and which integrate some technological innovations, have extensively demonstrated a faster improvement of acute respiratory failure in different patient populations, avoiding endotracheal intubation and facilitating the release of conventional invasive mechanical ventilation. In acute settings, NIV is currently the first-line treatment for moderate-to-severe chronic obstructive pulmonary disease exacerbation as well as for acute cardiogenic pulmonary edema and should be considered in immunocompromised patients with acute respiratory insufficiency, in difficult weaning, and in the prevention of postextubation failure. Alternatively, it can also be used in the postoperative period and in cases of pneumonia and asthma or as a palliative treatment. NIV is currently used in a wide range of acute settings, such as critical care and emergency departments, hospital wards, palliative or pediatric units, and in pre-hospital care. It is also used as a home care therapy in patients with chronic pulmonary or sleep disorders. The appropriate selection of patients and the adaptation to the technique are the keys to success. This review essentially analyzes the evidence of benefits of NIV in different populations with acute respiratory failure and describes the main modalities, new devices, and some practical aspects of the use of this technique.

Keywords: COPD; CPAP; acute pulmonary edema; acute respiratory failure; noninvasive ventilation; pressure support ventilation.

Figure 1

Pressure-time curves. Note: Spontaneous breathing (CPAP: 10 cmH₂O) and bilevel PS (IPAP: 22 cmH₂O; EPAP: 10 cmH₂O) with PS 12 cmH₂O. Reproduced from Masip J, Planas K. Noninvasive ventilation. In: Tubaro M, Danchin N, Filippatos G, Goldstein P, Vranckx P, Zahger D, editors. The ESC Text book of Intensive and Acute Cardiac Care. Oxford: Oxford University Press; 2011:215–226. By permission of Oxford University Press. Abbreviations: BiPAP, bilevel positive airway pressure; CPAP, continuous positive airway pressure; EPAP, expiratory positive airway pressure; IPAP, inspiratory positive airway pressure; PEEP, positive end-expiratory pressure; PS, pressure support.

Figure 2

Interfaces for noninvasive ventilation. Notes: (A) nasal mask; (B and C) oro-nasal masks; (D and E) full-face masks; (F) helmet; (G) nasal pillows. Pictures (A) and (G) were provided by JM Carratalà from H Universitario de Alicante, Spain.

Figure 3

Equipment needed for continuous positive airway pressure Boussignac technique. Notes: (A) Boussignac valve; (B) oro-nasal mask; nebulization device between (A) and (B); (C) 30-liter oxygen flowmeter; and (D) pressure gauge. The picture containing (A) and (B) was provided by JM Carratalà from H Universitario de Alicante, Spain.