Determinants of weaning and survival among patients with COPD who require mechanical ventilation for acute respiratory failure

The decision to institute MV in patients with COPD and ARF is difficult because the risk of complications is high and the long-term prognosis is poor. We reviewed our experience with 95 COPD patients with ARF requiring MV. Fifty-five patients required MV for more than two weeks, 72 were weaned successfully, and 59 died within one year of follow-up. Survival was associated with premorbid level of activity (p < .001), FEV₁ (p < .01), serum albumin level (p < .05), and severity of dyspnea (p < .01). Cor pulmonale on ECG, premorbid hypercarbia, and history of left ventricular failure were also more common among those who died. Weaning from MV was associated with premorbid level of activity (p < .001), FEV₁ (p < .001), albumin level (p < .05), and negative inspiratory pressure (p < .001) and respiratory rate during T-piece trial (p < .01). The duration of intubation was associated only with premorbid level of activity (p < .01). Predictive models for the weaning success and the one-year survival were developed.