Effectiveness of non invasive positive pressure ventilation in chronic obstructive pulmonary disease patients

27 patients diagnosed as chronic obstructive pulmonary disease (COPD) came with acute hypercapnic respiratory failure due to COPD and met the inclusion and exclusion criteria. They were managed by non invasive positive pressure ventilation (NIPPV). 21 cases showed success and 6 cases showed failure and were put on invasive mechanical ventilation within the first 24 h. It was shown that before initiation of NIPPV, the failed cases had significantly higher Body Mass Index (BMI) 34.7 compared to 28.1 in successful cases and significantly lower pH 7.20 ± 0.05 compared with 7.27 ± 0.04. After 1 h of initiation of NIPPV, the successful group showed improvement regarding pH and PaCO2, while the failed group showed worsening of the same parameters, with a significant difference (p value <0.001, 0.005), respectively. After 4 h, there was improvement in both groups regarding pH which reached normalization in the successful group, PaCO2, and PO2, with no statistical significant difference. There were significant differences in the respiratory rate (p value < 0.001), and the expiratory positive airway pressure (EPAP) (p value 0.024) between the two groups. Thus we can conclude that the use of NIPPV in such patients can be successful in around 78% of cases, however failure can be predicted by high BMI, initial lower pH and higher PaCO2, insignificant response to NIPPV after 1 h. They also show increased respiratory rate and need for higher expiratory positive airway pressure.