Patients with exacerbations of chronic obstructive pulmonary disease (COPD) form the most important group of patients for which NIV has proven beneficial. Invasive ventilation, with its risk of ventilator-associated pneumonia, has a high mortality when used for in COPD exacerbations. There are multiple randomized, controlled studies showing that noninvasive ventilation reduces mortality, patient discomfort, and length of-stay for exacerbations of COPD compared to standard therapy.¹
This robust evidence has been reviewed in NIV consensus and guidelines making NIV the standard-of-care treatment in severe exacerbations of COPD. In 2002, the British Standard of Care Committee recommended that any facility admitting patients with exacerbations of COPD should be prepared to initiate NIV. Several years later these recommendations still hold true. The Canadian Clinical practice guidelines for the use of noninvasive positive-pressure ventilation and noninvasive continuous positive airway pressure in the acute care setting recommend the use of noninvasive positive-pressure ventilation in addition to usual care in patients who have severe COPD exacerbations (pH < 7.35 and relative hypercarbia) as a first option for ventilator support. Sean Keenan et al assigned this indication a GRADE classification of 1A signifying there is high quality of evidence NIV supporting use therefore it is strongly recommended.¹
One of the earliest randomized studies on the use of NIV in patients with acute exacerbation of COPD was conducted in France by Dr Laurent Brochard et al. In this study 74% of patients assigned to the standard therapy group versus 26% of patients assigned to the NIV group were intubated. Importantly, this study highlighted a major difference in patient status within both groups at one hour. Patients in the standard therapy group experienced significant deterioration of encephalopathy scores, PH, PCO2, whereas the NIV group experienced significantly improved encephalopathy scores, PH, PO2, and respiratory rates. To this day, most NIV protocols include the need to assess patients after 1 hour of aggressively titrated noninvasive ventilatory support to determine whether there is an improvement in patient status, dyspnea and blood gases.²
There is also literature showing that not only is NIV more effective in terms of clinical outcomes, but it is also less costly. With increasing cost pressure on the healthcare systems NIV can become even more attractive: In a study from 2000 it was proven that the use of NIV and standard therapy for patients with acute respiratory failure is not only the most effective treatment, but it can also reduce costs provided that a careful patient selection takes place.³