RT Journal Article SR Electronic T1 Preoperative physical therapy reduces risk of postoperative atelectasis and pneumonia in people undergoing elective cardiac surgery JF Evidence Based Nursing JO Evid Based Nurs FD BMJ Publishing Group Ltd and RCN Publishing Company Ltd SP 13 OP 14 DO 10.1136/eb-2012-101199 VO 17 IS 1 A1 Elisabeth Westerdahl A1 Arne Tenling YR 2014 UL http://ebn.bmj.com/content/17/1/13.abstract AB