Noninvasive ventilation for acute respiratory failure

Abstract

Noninvasive ventilation (NIV) has emerged as a significant advance in the management of respiratory failure. There is now a wide body of prospective randomized-controlled trial data to support its use, particularly in the management of patients with acute or respiratory failure due to exacerbations of chronic obstructive pulmonary disease (COPD). Its successful application results in a more rapid resolution of the physiological derangements, reduces the need for intubation and, in larger studies, improves survival. A reduction in the number of infectious complications is a particular advantage.In patients with acute exacerbations of COPD there is evidence of benefit when NIV is introduced earlier in the course of the illness than would be the case for invasive ventilation and it should now be considered even with mild acidosis (pH<7.35) and tachypnoea (respiratory rate >23 breaths·min−1) after initial medical therapy.There is less clinical-trial data in patients with hypoxaemic respiratory failure, but again as with COPD those with less severe physiological disturbance are more likely to benefit. By contrast noninvasive continuous positive airways pressure, while being widely used has not been shown to reduce the need for intubation or to improve survival in patients with hypoxaemic respiratory failure, with the exception of acute cardiogenic pulmonary oedema.Noninvasive ventilation has been a real advance in the treatment of the critically ill. Most of the studies published to date, have excluded patients needing immediate intubation and it should be viewed as a complimentary technique rather than an alternative to invasive ventilation. It is best viewed as a means of preventing the need for endotracheal intubation and as a result should be introduced earlier than would be the case for invasive ventilation.

Hyperglycaemia as a predictor of outcome during non-invasive ventilation in decompensated COPD

“…This may explain why baseline pH was a poorer discriminant in the patient population now referred for NIV. In contrast, the initial respiratory rate was a good measure of treatment response, as has been seen elsewhere 1 2 5 24 25. A higher RR may reflect asynchrony of the patient and the ventilator, but it may also be a marker of a greater intrinsic respiratory load promoting a shortened inspiratory time and more hypercapnia 26 27.…”

Influence of ICU Case-Volume on the Management and Hospital Outcomes of Acute Exacerbations of Chronic Obstructive Pulmonary Disease*

“…The increase in patient mortality did not exceed what would be predicted from SAPS II data despite the increasing use of NIV, suggesting that NIV is not associated with impaired prognosis in these patients. Indeed, it is now well known that, in patients with hypercapnic respiratory failure, NIV improves outcomes, especially survival, by reducing the need for intubation and the prevalence of related complications (23)(24)(25). In the nineties, it was shown that the use of NIV for AECOPD had changed over time (26).…”

Effectiveness of non invasive positive pressure ventilation in chronic obstructive pulmonary disease patients

“…The first-line treatment of patients with acute respiratory failure (ARF) is mechanical ventilation either with positive or negative pressure, invasively or noninvasively [1]. A great deal of clinical research has shown that non-invasive ventilation (NIV), is a valuable form of treatment for ARF.…”