The primary postoperative outcomes were the occurrence of PPCs, LOS and re-admission
rate. A PPC was scored if one of the following criteria was present: (1) a patient received
(non-prophylactic) antibiotics for pulmonary reasons; (2) infiltrate on chest x ray diagnosed
by the radiologist; or (3) return to the intensive care unit (ICU) due to respiratory problems.LOS was defined as the time in hospital following surgery (in days). Unscheduled readmissions
to the hospital within 30 days of surgery due to complications were registered.
The secondary outcome was change in walking distance, measured by a 6-minute walk
test (6MWT) on the day of admission and the day of discharge. The 6MWT was performed by
a trained physiotherapist according to the guidelines of the American Thoracic Society [17].
Results were expressed in metres, and as a percentage of the predicted value