Effectiveness of non-invasive positive pressure ventilation differs between decompensated chronic restrictive and obstructive pulmonary disease patients

Abstract

Objective: To compare the efficiency of non-invasive positive pressure ventilation (NPPV) in decompensated patients with either chronic obstructive pulmonary disease (COPD) or chronic restrictive pulmonary disease.

Design: Retrospective study.

Setting: A 17-bed intensive care unit in a university teaching hospital.

Setting: Sixty-four patients with COPD (age: 70+/-13 years, sex ratio: 37 male to 27 female patients, forced expiratory volume in 1 s: 31+/-13% predicted) and 20 patients with chronic restrictive pulmonary disease (age: 75+/-9 years, sex ratio: 9 male to 11 female patients, total lung capacity: 57+/-17% predicted) consecutively treated with NPPV (facial mask, pressure support ventilation (PSV) +/- PEEP) for acute respiratory failure.

Measurements and results: There were no statistically significant differences between COPD and patients with chronic restrictive pulmonary disease in terms of cause of exacerbation, use of oxygen therapy or NPPV at home, severity of acute respiratory failure (ARF), mean delay from intensive care admission to initiation of NPPV and total duration of NPPV. Patients with chronic restrictive pulmonary disease had a lower success rate on NPPV (without need of tracheal intubation) than COPD (35% vs 67%, p=0.01). Causes of NPPV failure were not different between COPD and patients with restrictive disease. After 12 h of NPPV, restrictive patients who succeeded with NPPV had similar respiratory rate, minute ventilation and arterial blood gas to COPD patients. At the 3rd and 12th h of NPPV, improvements in pH and PaCO(2) were predictive of NPPV success in COPD, but not in restrictive patients.

Conclusion: The results of this retrospective study suggest that the effectiveness of NPPV for acute decompensation is less in patients with chronic restrictive pulmonary disease as compared to COPD.