Objective: To evaluate the effect of the early use of noninvasive positive pressure ventilation (NIPPV) on gas exchange, rate of endotracheal intubation and in-hospital mortality in patients with acute exacerbation of chronic obstructive pulmonary disease (COPD).
Methods: Thirty-six patients with acute exacerbation of COPD [7.25< or =arterial blood pH (pHa)<7.35, partial pressure of carbon dioxide in artery (PaCO(2))>45 mm Hg, 1 mm Hg=0.133 kPa] were enrolled in the study. The patients were divided randomly into standard therapy group (group A, n=18) and standard therapy+NIPPV group (group B, n=18). The patients in group A were treated with standard therapy only and those in group B were treated with both standard therapy and NIPPV with Bi-level positive airway pressure (BiPAP) mode. NIPPV should be maintained over 2 hours in the first time. In the first 3 days, the duration of NIPPV should not be less than 8 hours per day. In each group, heart rate (HR), respiratory rate (RR), parameters of gas exchange, and scale for accessory muscle use were measured at the time of enrollment (0 hour), 2 hours, 24 hours and 72 hours after randomization. In group B, the foregoing parameters were also observed at 24 hours after the end of NIPPV. Rate of endotracheal intubation and in-hospital mortality were recorded in each group.
Results: The general conditions were similar in both groups at 0 hour. Compared with that of 0 hour, marked improvement in HR, RR, pHa, PaCO(2) and scale for accessory muscle use was found only at 72 hours after treatment in group A. In group B, significant improvement in HR, RR, PaCO(2), partial pressure of oxygen in artery (PaO(2)) and scale for accessory muscle use was found 2 hours after the treatment. In this group, the foregoing parameters were improved continuously in the course of the treatment, and they showed no deterioration 24 hours after termination of NIPPV. The rate of endotracheal intubation in group B (11.1%) was significantly lower than that in group A (44.4%, P<0.05). In group B, the in-hospital mortality was slightly lower than that in group A (5.6% vs. 16.7%, P>0.05).
Conclusion: Early use of NIPPV can improve gas exchange, lessen respiratory muscle fatigue and decrease the need for intubation in patients with acute exacerbation of COPD.