RT Journal Article SR Electronic T1 Non-invasive positive pressure ventilation should be considered in patients with COPD and persistent hypercapnia at least 2 weeks after resolution of acute respiratory failure JF Evidence Based Nursing JO Evid Based Nurs FD BMJ Publishing Group Ltd and RCN Publishing Company Ltd SP 12 OP 12 DO 10.1136/eb-2017-102789 VO 21 IS 1 A1 Magnus Ekström YR 2018 UL http://ebn.bmj.com/content/21/1/12.abstract AB