Patient population
This was a retrospective observational study conducted at a single
institution. This study was approved by the Royal Papworth Hospital
Research and Development department and the requirement for patient
consent waived. All patients undergoing adult cardiac surgery at Royal
Papworth Hospital (United Kingdom) between January 2015 to April 2019
were included in this study. Demographic, intra-operative and
post-operative outcome data, including return to theatre, mediastinal
blood loss, blood product transfusion, and length of hospital and ICU
stay was collected prospectively. Mortality information was obtained
from the UK national patient administration system.