Shrinking the room for invasive ventilation in hypercapnic respiratory failure

Paolo Scarpazza,1 Cristoforo Incorvaia,2 Chiara Melacini,1 Roberta Cattaneo,1 Cristiano Bonacina,1 Gian Galeazzo Riario-Sforza,2 Walter Casali1 1Pneumology Unit, Ospedale Civile, Vimercate, 2Pulmonary Rehabilitation, Istituti Clinici di Perfezionamento, Milan, Italy Abstract: Noninvasive ventilation (NIV) was introduced as an alternative to invasive mechanical ventilation for acute respiratory failure caused from exacerbations of chronic obstructive pulmonary disease in the 1980s, and its use gradually rose worldwide. Seventy-eight patients (57 males, mean age 78.3 ± 9.2 years) undergoing NIV were evaluated. Of them, 48 (62.3%) had acute hypercapnic respiratory failure because of a chronic obstructive pulmonary disease exacerbation, and the remaining 30 had acute hypercapnic respiratory failure from other causes, mainly cardiac failure. All patients were treated by NIV using the bi-level positive airway pressure set up at high pressure/high backup rate. NIV was successful in 67 subjects (85.9%) and the patients were discharged, 57 of whom continued NIV at home and ten had spontaneous breathing. NIV was unsuccessful in eleven patients, ten of whom died and one was successfully treated by invasive mechanical ventilation. Significant differences were detected for a higher basal Glasgow Coma Scale score in successfully treated patients (P = 0.007), a higher basal Acute Physiology and Chronic Health Evaluation score in unsuccessfully treated patients (P = 0.004), and a lower pH after 1 hour in unsuccessfully treated patients (P = 0.015). These findings show a very high rate of success of NIV in patients with acute hypercapnic respiratory failure not only from chronic obstructive pulmonary disease but also from cardiac failure. This suggests that the use of invasive mechanical ventilation may be further reduced, with a decrease in its known complications as well. Keywords: invasive ventilation, noninvasive ventilation, acute respiratory failure