Effectiveness of non-invasive ventilation in acute exacerbation of COPD complicated with hypercapnic and a pH≥7.35 respiratory failur

Objective To investigate the effects of noninvasive positive-pressure ventilation(NPPV) in acute exacerbations of chronic obstructive pulmonary disease(AECOPD) patients admitted to hospitalization with chronic hypercapnic respiratory failure and an arterial pH≥7.35.Methods Forty-eight patients were randomized to receive standard medical therapy(control group) or medical therapy plus NPPV(NPPV group).Respiratory rate(R),heart rate,arterial blood gases,dyspnoea symptom score(DSS) were measured.Need for admission to intensive care unit(ICU) and duration of hospitalization were compared and complications was recorded.Results Arterial pH and PaCO2 improved in two groups,but change significantly in the NPPV group.The NPPV group showed a faster decrease in R(P0.05),faster improvement in PaCO2(P0.05) and pH(P0.05) after 24 h,DSS reduced more obviously.Blood gases,DSS showed similar improvement in both groups at discharge.NPPV resulted in a shorter hospital stay(P0.05).Abdominal distension or anxiety was the most common complication.Conclusion Administration of NPPV in AECOPD patients admitted with chronic hypercapnic respiratory failure and a pH≥7.35 result in a faster improvement of blood gases and symptom,reduced hospital stay.